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1.
BMC Med Imaging ; 19(1): 62, 2019 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-31390990

RESUMEN

BACKGROUND: Imaging methods for the plantar fascia have included radiography, ultrasound and magnetic resonance imaging (MRI), all of which have provided valuable information. This study assessed the reliability of ultrasonography examinations of the plantar fascia using a comparative study. METHODS: Fifty healthy adult volunteers (25 males and 25 females, mean age 31.6 ± 3.5 years) were included in this study. Images of the plantar fascia from 100 ft were acquired with ultrasonography, CT and MRI. Ultrasound was used to measure the thickness of the plantar fascia. Imaging data from CT and MRI in a DICOM format were transformed into the Materialise Mimics Innovation Suite 16.0 software for digital analysis. SPSS software (SPSS, USA) was used for statistical analysis. The reliability was established by a t-test. Moreover, 42 patients with unilateral plantar fasciitis were examined by ultrasonography. RESULTS: There were no significant differences between the three imaging modalities for patients of the same sex (P > 0.05). There were no statistically significant differences between the left and right sides for patients of the same sex (P > 0.05), but the difference between males and females was statistically significant (P < 0.01). There were no significant differences between US, CT and MRI in the normal group, but there were significant differences in the plantar fasciitis group evaluated with ultrasound. The plantar fascii of normal male subjects are significantly thicker than those of the normal female. CONCLUSION: Ultrasonography can be a relatively simple and reliable method for the measurement of plantar fascia thickness.


Asunto(s)
Fascitis Plantar/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía/métodos , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Caracteres Sexuales , Programas Informáticos , Adulto Joven
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(4): 1095-9, 2016 Apr.
Artículo en Zh | MEDLINE | ID: mdl-30052006

RESUMEN

The research on the distribution and component of olivine is one of great significance to evaluate the geologic evolution of igneous planetary bodies such as the Moon. In this paper, the Sinus Iidium, as the survey region, was explored by Chang's serial satellite. Here we present an olivine survey of the Sinus Iridium by using Spectral Feature Fitting (SFF) method based on the M3 data. The exposures of olivine were located in the northern crater wall and at the foot of Montes Jura, which were associated with plagioclase and little anorthosite. The stratigraphic units of the located formation were the interior crater slopes and debris ejected from the impact-formed Iridium crater, and the geological age was relatively older. The Mg number of the lunar olivine samples was dependent variables, and the band center of the lunar olivine spectrums were independent, which derived from the fitting analysis using Modified Gaussian Model (MGM). The quantitative inversion models of Mg number (Fo#) of the lunar olivine is established with multiple linear regression analysis. On this basis, the Mg number of the olivine rich point in the Sinus Iridium are calculated with quantitative inversion models of Mg number (Fo#). The result shows that, the Fo# of olivine in the Sinus Iridium are relatively high. The mean value of Fo# is Fo~80.84. As mantle olivine would be expected to be quite Mg-rich, it is suggested that at the vast majority of the olivine detected in the Sinus Iridium come from upper mantle of the Moon.

3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(12): 3836-41, 2016 Dec.
Artículo en Zh | MEDLINE | ID: mdl-30234952

RESUMEN

Tissue intrinsic fluorescence spectrum refers to the fluorescence that is not impaired by tissue absorption and scattering which has the ability to reflect tissue biochemical properties. In order to reduce the influence of tissue absorption and scattering properties on tissue fluorescence spectrum, and then recover tissue intrinsic fluorescence spectrum, a tissue spectrum detection system based on fiber-optic probe was developed for the measurement of tissue fluorescence spectrum and diffusion reflectance spectrum at the same place. On the other hand, diffusion theory was introduced to extract the tissue physiological parameters from the measurement tissue diffusion reflectance spectrum, which included blood volume fraction, oxyhemoglobin saturation, melanin content, reduce scattering coefficient at 500 nm and the ratio of rayleigh scattering and the total scattering. Then tissue optical parameters in visible wavelengths were calculated. According to the tissue optical parameters and measured tissue diffusion spectrum, the intrinsic fluorescence spectrum was recovered from the measured fluorescence. Based on this, clinical trials were conducted to measure human skin fluorescence spectrum and diffusion reflectance spectrum, and then to recover skin intrinsic fluorescence spectrum. Finally, the accumulation of Advanced Glycation End products (AGE) in human skin was evaluated and the probability of diabetes mellitus was predicted. The result shows that the sensitivity and specificity were 69% and 0.75% respectively, when the measured fluorescent was used to screening diabetes mellitus. At the same specificity, the sensitivity was 90% when the recovered intrinsic fluorescence was employed to screening diabetes mellitus.


Asunto(s)
Espectrometría de Fluorescencia , Difusión , Tecnología de Fibra Óptica , Humanos , Dispersión de Radiación
4.
Arch Gynecol Obstet ; 289(1): 67-73, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23828444

RESUMEN

INTRODUCTION: Placental mRNA can now be detected in maternal whole blood, raising the possibility of using maternal blood for noninvasive prenatal diagnosis (NIPD) of trisomy 21. We aimed to identify new mRNA-single nucleotide polymorphism (mRNA-SNP) markers suitable for use in reverse-transcriptase multiplex ligation-dependent probe amplification (RT-MLPA) to develop a more reliable diagnostic method for trisomy 21 in Chinese subjects. MATERIALS AND METHODS: Using sequencing, we determined the status of SNPs in genes expressed in the placenta and calculated their heterozygote frequencies to determine which loci were suitable for use in RT-MLPA. Cell-free fetal RNA was extracted from peripheral blood samples of 246 women at 12-24 weeks of pregnancy, and the SNP loci selected were analyzed by RT-MLPA, followed by capillary electrophoresis. Karyotype analyses were used to confirm the diagnosis of trisomy 21. RESULTS: As compared with karyotype analysis, the diagnostic sensitivity and specificity of RT-MLPA were excellent (95 and 100% in different gestational weeks). CONCLUSION: The RT-MLPA technique is a suitable and reliable method for the diagnosis of trisomy 21. Use of RT-MLPA with the SNP markers described here shows good specificity, high sensitivity, and high throughput potential, making this technique suitable for NIPD in clinical practice.


Asunto(s)
Síndrome de Down/diagnóstico , Reacción en Cadena de la Polimerasa Multiplex/métodos , Polimorfismo de Nucleótido Simple , Diagnóstico Prenatal/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Síndrome de Down/genética , Femenino , Marcadores Genéticos , Humanos , Cariotipificación , Embarazo , Sensibilidad y Especificidad
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(5): 1327-31, 2014 May.
Artículo en Zh | MEDLINE | ID: mdl-25095432

RESUMEN

Advanced glycation end products (AGEs) are highly associated with hyperglycemia in human skin tissue, and they also have the autofluorescence characteristic. A self-developed optical noninvasive detection device was used to measure the autofluorescence in human skin tissue, and then a neural network pattern recognition model was used to assess the risk of diabetes mellitus of the subject under survey. After the fluorescence spectra were acquired and processed with principal component analysis, four of the leading principal components were chosen to represent a whole spectrum. The established neural network pattern recognition model has 4 input nodes, 6 hidden nodes and 1 output node. A dataset consisting of 487 cases collected in Anhui Provincial Hospital was used to train the model. Seventy percent cases were used as the training set, 15% as the validation set and 15% as the test set. The model can output subject's risk of diabetes mellitus, or a dichotomous judgment. Receiver operating characteristic curve can be drawn with the area under curve of 0. 81, with standard error of 0. 02. When using 0. 5 as the threshold between diabetes mellitus and non-diabetes mellitus, the sensitivity and specificity of this model is 72. 4% and 77. 6% respectively, and the overall accuracy is 74. 9%. The method using human skin autofluorescence spectrum combined with neural network pattern recognition model is proposed for the first time, and the results show that this method has a better screening effect compared with currently used fasting plasma glucose and HbAlc.


Asunto(s)
Diabetes Mellitus/diagnóstico , Redes Neurales de la Computación , Fluorescencia , Productos Finales de Glicación Avanzada/análisis , Humanos , Hiperglucemia/diagnóstico , Reconocimiento de Normas Patrones Automatizadas , Medición de Riesgo , Sensibilidad y Especificidad , Piel , Espectrometría de Fluorescencia
6.
Front Med (Lausanne) ; 10: 1218720, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38034536

RESUMEN

Pelvic fractures mostly result from high-energy injuries in life; the longitudinal fracture of the sacrum is the most common type of sacrum fracture. This study was designed to evaluate the accuracy, safety, and efficacy of percutaneous sacroiliac joint screw placement in the treatment of longitudinal sacrum fractures with the assistance of unobstructed orthopaedic surgery robots. According to different surgical methods, 32 patients were divided into robot group and free hand group, with 16 patients in each group. The operation time, intra-operative blood loss, intra-operative fluoroscopy times, screw placement angle deviation were collected. There were statistically significant differences in terms of angle deviation of screw placement (1.96 ± 0.75° vs. 2.87 ± 1.03°; p = 0.0145), deviation of the guide needle (1.92 ± 0.93 mm vs. 2.91 ± 1.22 mm; p = 0.0209), intra-operative fluoroscopy time (7.25 ± 1.72 s vs. 20.93 ± 5.64 s; p = 0.0000), insertion time of each sacroiliac joint screw (14.72 ± 2.66 min vs. 29.21 ± 5.18 min; p = 0.0000). There was no statistically significant difference in terms of blood loss (100.21 ± 7.37 mL vs. 102.52 ± 8.15 mL; p = 0.4136). These results suggest that orthopaedic surgery robot for the treatment of longitudinal sacrum fracture is safer and provides less irradiation than the traditional freehand methods.

7.
BMC Musculoskelet Disord ; 12: 76, 2011 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-21492461

RESUMEN

BACKGROUND: Exposure of the anterior or lateral lumbar via the retroperitoneal approach easily causes injuries to the lumbar plexus. Lumbar plexus injuries which occur during anterior or transpsoas lumbar spine exposure and placement of instruments have been reported. This study aims is to provide more anatomical data and surgical landmarks in operations concerning the lumbar plexus in order to prevent lumbar plexus injuries and to increase the possibility of safety in anterior approach lumbar surgery. METHODS: To study the applied anatomy related to the lumbar plexus of fifteen formaldehyde-preserved cadavers, Five sets of Virtual Human (VH) data set were prepared and used in the study. Three-dimensional (3D) computerized reconstructions of the lumbar plexus and their adjacent structures were conducted from the VH female data set. RESULTS: The order of lumbar nerves is regular. From the anterior view, lumbar plexus nerves are arranged from medial at L5 to lateral at L2. From the lateral view, lumbar nerves are arranged from ventral at L2 to dorsal at L5. The angle of each nerve root exiting outward to the corresponding intervertebral foramen increases from L1 to L5. The lumbar plexus nerves are observed to be in close contact with transverse processes (TP). All parts of the lumbar plexus were located by sectional anatomy in the dorsal third of the psoas muscle. Thus, access to the psoas major muscle at the ventral 2/3 region can safely prevent nerve injuries. 3D reconstruction of the lumbar plexus based on VCH data can clearly show the relationships between the lumbar plexus and the blood vessels, vertebral body, kidney, and psoas muscle. CONCLUSION: The psoas muscle can be considered as a surgical landmark since incision at the ventral 2/3 of the region can prevent lumbar plexus injuries for procedures requiring exposure of the lateral anterior of the lumbar. The transverse process can be considered as a landmark and reference in surgical operations by its relative position to the lumbar plexus. 3D reconstructions of the lumbar plexus based on VCH data provide a virtual morphological basis for anterior lumbar surgery.


Asunto(s)
Gráficos por Computador , Simulación por Computador , Imagenología Tridimensional , Vértebras Lumbares/inervación , Plexo Lumbosacro/anatomía & histología , Modelos Anatómicos , Raíces Nerviosas Espinales/anatomía & histología , Anciano , Anciano de 80 o más Años , Artroplastia/efectos adversos , Cadáver , Femenino , Humanos , Vértebras Lumbares/irrigación sanguínea , Vértebras Lumbares/cirugía , Plexo Lumbosacro/lesiones , Masculino , Persona de Mediana Edad , Músculos Psoas/anatomía & histología , Fusión Vertebral/efectos adversos , Raíces Nerviosas Espinales/lesiones
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(6): 1644-7, 2011 Jun.
Artículo en Zh | MEDLINE | ID: mdl-21847950

RESUMEN

Landsat-TM (Theme Mapper) and EOS (Earth Observing System)-MODIS (MODerate resolution Imaging Spectrora-diometer) Terra/Aqua images were used to monitor the macro-algae (Ulva prolifera) bloom since 2007 at the Yellow Sea and the East China Sea. At the turbid waters of Northern Jiangsu Shoal, there is strong spectral mixing behavior, and satellite images with finer spatical resolution are more effective in detection of macro-algae patches. Macro-algae patches were detected by the Landsat images for the first time at the Sheyang estuary where is dominated by very turbid waters. The MODIS images showed that the macro-algae from the turbid waters near the Northern Jiangsu Shoal drifted southwardly in the early of May and affected the East China Sea waters; with the strengthening east-asian Summer Monsoon, macro-algae patches mainly drifted in a northward path which was mostly observed at the Yellow Sea. Macro-algae patches were also found to drift eastwardly towards the Korea Peninsular, which are supposed to be driven by the sea surface wind.


Asunto(s)
Eutrofización , Tecnología de Sensores Remotos , Ulva , China , Estaciones del Año , Agua de Mar , Viento
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(2): 313-7, 2010 Feb.
Artículo en Zh | MEDLINE | ID: mdl-20384114

RESUMEN

The chlorophyll-a concentration in waters is one of the main parameters of water color remote sensing in case II waters. There is a reflectance peak in red band region because of inherent optical properties. Based on the coefficients of absorption and backscattering of waters, colored dissolved organic matter (CDOM), tripton and chlorophyll-a, the reflectance of remote sensing was simulated according to the forward radiation transfer model without the consideration of fluorescence peak. The reflectance peak intensity and reflectance peak position at different wavelengths in red band region were analyzed with different chlorophyll-a concentration. There is a good linear relationship between the red reflectance peak intensity and chlorophyll-a concentration when the chlorophyll-a concentration is 1-50 microg x L(-1). But the linear relationship between the reflectance peak intensity and chlorophyll-a concentration will decrease with the increasing chlorophyll-a concentration. When chlorophyll-a concentration is up to 1 000 microg x L(-1), the logarithm relationship between the reflectance peak intensity and chlorophyll-a concentration is better than linear relationship. The wavelength position of reflectance peak in red band region will shift towards larger wave-length at logarithmic growth rate with increasing chlorophyll-a concentration, and the logarithm relationship will be more apparent with the inoreasing chlorophyll-a concentration. The same trend happens to the reflectance peak intensity and the wavelength position of peak in red region with different in-water constituents, such as CDOM, tripton and so on. Furthermore, according to the comparison with fluorescence peak, the authors also found that the reflectance peak intensity and the wavelength position of peak in red region are different from those of the fluorescence peak.

10.
Surg Radiol Anat ; 31(6): 425-30, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19190849

RESUMEN

INTRODUCTION: Male genital dysfunction was recognized as a complication following anterior approach lumbar surgery. Disruption of efferent sympathetic pathways such as the abdominal aortic plexus (AAP) and superior hypogastric plexus (SHP) which lied pre-abdominal aorta and iliac artery had been thought as the main reason. Though there were some clinical reports of retrograde ejaculation, the applied anatomic study of the autonomic nerve anterior to the lumbar was little. The purpose was to find out a lumbar surgery approach which was ejaculation preservation through the detailed study of the anatomy and histology observation of the autonomic nerve anterior to the lumbar vertebrae. METHODS: The lumbar region of ten male cadavers was dissected and analyzed. We investigated the relationship between the peritoneum and abdominal aorta, iliac artery and sacral promontory fascia, as well as the trend and distribution of the autonomic nerve and SHP anterior to the L5-S1. We also observed the distribution of autonomic nerve at retroperitoneum through hematoxylin and eosin (HE)-stained tissues pre-aorta, para-aorta, and pre-vertebrae sacrales. RESULTS: Superior hypogastric plexus, which deviated to left, located in a triangle formed by the common iliac arteries and its bilateral branches, its truck sited anterior to the lumbarsacral space in seven cases (70%), and anterior to sacrum in three cases (30%); at the aortic bifurcation, SHP strided over left iliac artery from left-hand side, then located in front of sacrum in four cases (40%), and sifted to the left at the lumbar sacral promontory in six cases (60%); from both anatomic and histological view, the autonomic nerve plexus lying in an fascia layer of retroperitoneum. CONCLUSION: At the anterior approach lumbar surgery of trans-peritoneum, we should choose the right-hand side incision; the SHP should be pushed aside carefully from right to left along intervertebral disc. The accurate surgical plane was at the deeper layer of autonomical nerve fascia; we also could lift the complete autonomical nerve layer which lies behind the aorta and lumbar sacral promontory, so that the autonomic nerve could be preserved.


Asunto(s)
Plexo Hipogástrico/anatomía & histología , Vértebras Lumbares/inervación , Complicaciones Posoperatorias/prevención & control , Humanos , Vértebras Lumbares/cirugía , Masculino , Espacio Retroperitoneal/anatomía & histología , Disfunciones Sexuales Fisiológicas/prevención & control
11.
Chin J Traumatol ; 12(3): 177-80, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19486561

RESUMEN

OBJECTIVE: To develop a novel method of spinal pedical stereotaxy by reverse engineering and rapid prototyping techniques, and to validate its accuracy by experimental and clinical studies. METHODS: A 3D reconstruction model for the desired lumbar vertebra was generated by using the Mimics 10.11 software, and the optimal screw size and orientation were determined using the reverse engineering software. Afterwards, a drill template was created by reverse engineering principle, whose surface was the antitemplate of the vertebral surface. The drill template and its corresponding vertebra were manufactured using the rapid prototyping technique. RESULTS: The accuracy of the drill template was confirmed by drilling screw trajectory into the vertebral biomodel preoperatively. This method also showed its ability to customize the placement and size of each screw based on the unique morphology of the lumbar vertebra.The drill template fits the postural surface of the vertebra very well in the cadaver experiment. Postoperative CT scans for controlling the pedicle bore showed that the personalized template had a high precision in cadaver experiment and clinical application. No misplacement occurred by using the personalized template. During surgery, no additional computer assistance was needed. CONCLUSIONS: The authors have developed a novel drill template for lumbar pedicle screw placement with good applicability and high accuracy. The potential use of drill templates to place lumbar pedicle screws is promising. Our methodology appears to provide an accurate technique and trajectory for pedicle screw placement in the lumbar spine.


Asunto(s)
Tornillos Óseos , Vértebras Lumbares/cirugía , Procedimientos Ortopédicos/instrumentación , Cirugía Asistida por Computador/instrumentación , Adulto , Anciano , Femenino , Humanos , Imagenología Tridimensional , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
12.
Chin J Traumatol ; 12(4): 214-7, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19635214

RESUMEN

OBJECTIVE: To provide a new method in the fixation of sacral fracture by means of three-dimensional reconstruction and reverse engineering technique. METHODS: Pelvis image data were obtained from three-dimensional CT scan in patients with sacral fracture. The data were transferred into a computer workstation. The three-dimensional models of pelvis were reconstructed using Amira 3.1 software and saved in STL format. Then the three-dimensional fracture models were imported into Imageware 9.0 software. Different situations of reduction (total reduction, half reduction and non-reduction) were simulated using Imageware 9.0 software. The best direction and location of extract iliosacral lag screws were defined using reverse engineering according to these three situations and navigation templates were designed according to the anatomic features of the postero-iliac part and the channel. The exact navigational template was made by rapid prototyping. Drill guides were sterilized and used intraoperatively to assist in surgical navigation and the placement of iliosacral lag screws. RESULTS: Accurate screw placement was confirmed with postoperative X-ray and CT scanning. The navigation template was found to be highly accurate. CONCLUSION: The navigation template may be a useful method in minimal-invasive fixation of sacroiliac joint fracture.


Asunto(s)
Fijación de Fractura/métodos , Imagenología Tridimensional , Procedimientos de Cirugía Plástica/métodos , Sacro/lesiones , Tornillos Óseos , Femenino , Humanos , Masculino , Sacro/cirugía
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(1): 161-4, 2009 Jan.
Artículo en Zh | MEDLINE | ID: mdl-19385229

RESUMEN

Hyperspectral remote sensing offers the potential to detect water quality variables such as Chl-a by using narrow spectral channels of less than 10 nm, which could otherwise be masked by broadband satellites such as Landsat TM. Fluorescence peak of the red region is very important for the remote sensing of inland and coastal waters, which is unique to phytoplankton Chl-a that takes place in this region. Based on in situ water sampling and field spectral measurement from 2004 to 2006 in Nanhu Lake, the features of the spectral reflectance were analyzed in detail with peak position shift. The results showed: An exponential fitting model, peak position = a(Chl-a)b, was developed between chlorophyll-a concentration and fluorescence peak shift, where a varies between 686.11 and 686.29, while b between 0.0062 and 0.0065. It was found that the better the spectral resolution, the higher the precision of the model. Except that, the average of peak shift showed a high correlation with the average of different Chl-a grades, and the determination coefficient (R2) was higher than 0.81. It contributed significantly to the increase in the accuracy of the derivation of chlorophyll values from remote sensing data in Nanhu Lake. There is satisfactory correspondence between hyperspectral models and chl-a concentration, therefore, it is possible to monitor the water quality of Nanhu lake throngh the hyperspetral remote sensing data.


Asunto(s)
Clorofila/química , Fluorescencia , Agua/análisis , Ecosistema , Monitoreo del Ambiente , Agua Dulce , Luz , Fitoplancton , Agua/química
14.
Zhonghua Wai Ke Za Zhi ; 47(5): 359-62, 2009 Mar 01.
Artículo en Zh | MEDLINE | ID: mdl-19595014

RESUMEN

OBJECTIVE: To observe the primary clinical result of digital template as navigation to the upper cervical pedicle instrumentation. METHODS: CT scan of upper cervical vertebrae was performed. 3-D model of upper cervical vertebrae was reconstructed by software Amira 3.1 and was preserved in STL format. Then 3-D model was run in software UG Imageware 12.0, the best pedicle channel was extracted according to the reverse engineering principle. A virtual navigational template was established according to he lamina anatomic trait, and the best pedicle channel. The virtual vertebrae and navigational template were manufactured using rapid prototyping. The navigational template was sterilized and used intra operative to assist with the placement of pedicle screw. The Accuracy of screw placement was confirmed with postoperative X-ray and CT scanning. RESULTS: The digital navigational template had been established and used in the 3 cases, the good trajectory of cervical pedicle had been showed by the CT scan of post operation. There were not complications of related pedicle screw insertion. CONCLUSIONS: A novel method of upper cervical pedicle location using Reverse Engineering and rapid prototyping has been developed; the navigational template is found to be highly accuracy and has great expectation.


Asunto(s)
Vértebras Cervicales/cirugía , Neuronavegación , Cirugía Asistida por Computador , Adulto , Tornillos Óseos , Vértebras Cervicales/diagnóstico por imagen , Simulación por Computador , Femenino , Humanos , Imagenología Tridimensional , Persona de Mediana Edad , Modelos Anatómicos , Fusión Vertebral , Tomografía Computarizada por Rayos X
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(3): 624-8, 2008 Mar.
Artículo en Zh | MEDLINE | ID: mdl-18536428

RESUMEN

Soil spectral reflectance is the comprehensive representation of soil physical and chemical parameters, and its study is the physical basis for soil remote sensing and provides a new way and standard for soil properties themselves' research. Soil room spectra significantly correlate with that derived from hyperspectral images. So the room spectra are very important for soil taxonomy and investigation. To seek for the feasibility of soil taxonomy on the basis of topsoil reflectance spectral characteristics, and provide the theory foundation for quick soil taxonomy based on remote sensing methods, the spectral reflectance in the visible and near infrared region (400-2 500 nm) of 248 soil samples (black soil, chernozem, meadow soil, blown soil, alluvial soil) collected from Nongan county, Jilin province was measured with a hyperspectral device in room, and the soil spectral characteristics were determined with continuum removal method, and soil spectral indices (spectral absorption area, depth and asymmetry) were computed, which were introduced into BP network models as external input variables. The models consist of three layers (input, output and hidden layer), the training function is "TRAINLM", learning function "LEARNGDM", and transferring function "TAN SIG". The results showed that: (1) There are some differences among different soils in their spectral characteristics, but with similar parental matrix and climate, the spectral differences of soils in Nongan county are not significant. So it's difficult to analyze soil spectral characteristics based on soil reflectance. (2) The curves after continuum removal strengthened soil spectral absorption characteristics, and simplified soil spectral analysis. The soil spectral curves in Nongan county mainly have five spectral absorption vales at 494, 658, 1 415, 1 913 and 2 206 nm, and the former two vales are caused by soil organic matter, Fe and mechanical composition, the latter three are due to soil moisture; the differences of the latter three vales among different soils are not apparent, and the significant differences are in the former two vales region. (3) Soil reflectance is sensitive to organic matter, soil moisture, Fe, mechanical composition, roughness, and so on. The sensitivity of soil spectral indices derived with continuum removing method is decreased. Then the models with these indices as input variables are more stable and general. As the input variables were external, the BP network model based on the former two vales' shape characteristics was better than that based on reflectance values or all five vales, the classifying accuracy of the main three soils (chernozem, meadow soil, blown soil) was bigger than 60%, and the model could be used for soil taxonomy. However, this work still needs further study, and to improve classifying accuracy, auxiliary data, such as topography, vegetation, and land use should be introduced.


Asunto(s)
Suelo/análisis , Espectrofotometría/métodos , Espectroscopía Infrarroja Corta/métodos , Hierro/análisis
16.
Wideochir Inne Tech Maloinwazyjne ; 13(4): 518-524, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30524624

RESUMEN

INTRODUCTION: Spinal pedicle screw internal fixation has been widely used in adult spine injury fixation. Due to being in a period of continuous growth and development, the spine of children at different ages shows different characteristics from adults in terms of anatomy, physiological function, and biomechanics. Furthermore, because the pedicle of children is small, has large anatomic variation, and has complex adjacent relationships, the surgical risk is extremely high. How to improve the screwing accuracy is the key to the success of children's pedicle internal fixation. Therefore, applying the concept of digitized and individualized screwing will be of great significance to children's pedicle screwing. AIM: To investigate the morphologies, development patterns, and aging characteristics of the lumbar vertebral pedicle (LVP) in children aged 6-11 years, and to provide a theoretical basis for screw implantation and related biomechanical studies. MATERIAL AND METHODS: A total of 60 children aged 6-11 years were selected for the intergroup measurement and statistical analysis of their lumbar diameter, pedicle diameter, screw canal length (SCL), etc. RESULTS: Generally, the vertebral foramen diameter (ID), sagittal diameter (SD), pedicle width (PW), and SCL as well as the pedicle height (PH) exhibited an increasing trend with age and increasing vertebral sequence among children aged 6-11 years. CONCLUSIONS: By observing the LVP in children using 3D digital reconstruction technology, the morphology of the spinal canal and pedicles at different lumbar segments showed obvious development patterns, and the best treatment protocol should be selected according to the LVP characteristics in clinical applications.

17.
Yi Chuan ; 29(7): 800-4, 2007 Jul.
Artículo en Zh | MEDLINE | ID: mdl-17646144

RESUMEN

Mutation of GJB1 gene was investigated in two families with X-linked Charcot-Marie-Tooth disease. Genomic DNA from venous blood samples was prepared. The coding sequence of the GJB1 gene was amplified from genomic DNA. PCR products were analyzed by single strand conformational polymorphism (SSCP) method. The PCR product having an abnormal pattern was sequenced to detect the mutation. It was found that the samples of all patients and one little girl with normal phenotype showed an abnormal SSCP band, but not detected in the other unaffected members in the first large family. In the second small family, an abnormal SSCP band was found in all the patients, but not detected in the unaffected member. The result of DNA sequencing demonstrated that both families had a same mutation of 622G-->A, which resulted in a substitution of Glu208Lys. This mutation has not been reported previously in China.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/genética , Cromosomas Humanos X/genética , Conexinas/genética , Mutación , Secuencia de Bases , Análisis Mutacional de ADN , Femenino , Humanos , Masculino , Linaje , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Proteína beta1 de Unión Comunicante
18.
Zhonghua Wai Ke Za Zhi ; 45(4): 243-5, 2007 Feb 15.
Artículo en Zh | MEDLINE | ID: mdl-17502020

RESUMEN

OBJECTIVE: To observe the normal structure of lumbar plexus in the virtual Chinese Human (VCH) Female I and Male III and establish a digitized visible model of their lumbar plexus. METHODS: The cross-sectional images from the VCH Female I and Male III dataset were reviewed to study lumbar plexus structures on a section-by-section basis. The nerve roots, major psoas muscle and blood vessels were also observed. Three-dimensional computerized reconstructions of lumbar plexus and its adjacent structures were conducted from these data using Amira 3.1 (TGS) imaging software respectively. RESULTS: The three-dimensional reconstructed visible models perfectly displayed the anatomic relationships of lumbar plexus structures and their adjacent structures. CONCLUSIONS: VCH Female I and Male III dataset can provide complete and accurate data of main structure of lumbar plexus. The digitized models of lumbar plexus offer unique insights into the complex anatomy, and morphologic data for imaging diagnosis and treatment of the injury of lumbar plexus.


Asunto(s)
Plexo Lumbosacro/anatomía & histología , Proyectos Humanos Visibles , Anatomía Transversal , Femenino , Humanos , Imagenología Tridimensional , Masculino , Modelos Anatómicos
20.
Chin Med J (Engl) ; 119(19): 1616-21, 2006 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-17042974

RESUMEN

BACKGROUND: Studies of highly exposed persistently seronegative (HEPS) individuals may provide valuable information on mechanisms of protection and on vaccine design. Cellular immune responses play a critical role in containing human immunodeficiency virus. However, the cellular immune responses in HEPS individuals have not been thoroughly assessed at the entire viral genome level. METHODS: Ten HEPS Chinese with a history of frequent penetrative vaginal intercourse (mean frequency, at least once a week), with some unprotected sexual contact occurring in the weeks or days immediately before enrollment, 25 HIV-1 seropositive individuals, 10 HIV-1-seronegative healthy individuals with low-risk sexual behavior and no history suggestive of exposure to HIV-1 infection were enrolled. HIV-1-specific T cell responses were comprehensively analyzed by an interferon-gamma Elispot assay against 770 overlapping peptides spanning all HIV-1 proteins. RESULTS: HIV-1-specific T-cell responses of interferon-gamma secretion were identified in 3 (30%) out of 10 HEPS individuals; the specific cytotoxic T lymphocytes were targeted at Pol (2/10), Env (2/10), and Tat (1/10). HIV-1-specific T-cell responses of interferon-gamma secretion were identified in 20 (80%) out of 25 seropositive intravenous drug users (IDUs), revealing that all HIV-1 proteins and protein subunits could serve as targets for HIV-1-specific CD8(+) T cell responses with 85% recognizing Gag, 80% recognizing Nef, 75% recognizing Pol, 60% recognizing Env, 55% recognizing Vpu, 45% recognizing Vpr, 20% recognizing Vif, 20% recognizing Tat and 15% recognizing Rev in these seropositive individuals. None of the seronegative healthy individuals gave the positive T-cell responses. CONCLUSIONS: About 30% of HEPS Chinese mounted HIV-1 specific T cell immune responses. Cell-mediated immunity against HIV-1 may be developed through non-productive infections.


Asunto(s)
Seronegatividad para VIH/inmunología , VIH-1/inmunología , Linfocitos T Citotóxicos/inmunología , Adulto , Femenino , Humanos , Interferón gamma/biosíntesis , Masculino , Receptores CCR5/genética
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