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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(6): 877-884, 2023 Jun 06.
Artículo en Chino | MEDLINE | ID: mdl-37357207

RESUMEN

Objective: Analysis and investigation of pathogenic characteristics of polymyxin-and carbapenem-resistant Klebsiella pneumoniae (PR-CRKP). Methods: A total of 23 PR-CRKP strains isolated from clinical specimens from the General Hospital of Southern Theater Command from March 2019 to July 2021 were retrospectively collected, Whole-genome sequencing was performed on 23 PR-CRKP strains, resistance genes were identified by comparison of the CARD and the ResFinder database, high-resolution typing of PR-CRKP strains was analyzed by core genomic multilocus sequencing (cgMLST) and single nucleotide polymorphism (SNP); polymyxin resistance genes were determined by PCR and sequencing. Results: All PR-CRKP strains were KPC-2 producing ST11 types. cgMLST results showed that the evolutionary distance between the PR-CRKP strains and Klebsiella pneumoniae in mainland China was 66.44 on average, which is more closely related than foreign strains; the 23 PR-CRKP strains were divided into 3 main subclusters based on SNP phylogenetic trees, with some aggregation among Clade 2-1 in the isolation department and date. The two-component negative regulatory gene mgrB has seven mutation types including point mutations, different insertion fragments and different insertion positions. Conclusion: The close affinity of PR-CRKP strains indicate the possibility of nosocomial clonal transmission and the need to strengthen surveillance of PR-CRKP strains to prevent epidemic transmission of PR-CRKP.


Asunto(s)
Antibacterianos , Carbapenémicos , Humanos , Carbapenémicos/farmacología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Klebsiella pneumoniae/genética , Polimixinas/farmacología , beta-Lactamasas , Filogenia , Estudios Retrospectivos , Tipificación de Secuencias Multilocus , Pruebas de Sensibilidad Microbiana
2.
Zhonghua Xin Xue Guan Bing Za Zhi ; 51(5): 521-525, 2023 May 24.
Artículo en Chino | MEDLINE | ID: mdl-37198124

RESUMEN

Objectives: This study sought to describe our institutional experience of repeated percutaneous stellate ganglion blockade (R-SGB) as a treatment option for drug-refractory electrical storm in patients with nonischemic cardiomyopathy (NICM). Methods: This prospective observational study included 8 consecutive NICM patients who had drug-refractory electrical storm and underwent R-SGB between June 1, 2021 and January 31, 2022. Lidocaine (5 ml, 1%) was injected in the vicinity of the left stellate ganglion under the guidance of ultrasound, once per day for 7 days. Data including clinical characteristics, immediate and long-term outcomes, and procedure related complications were collected. Results: The mean age was (51.5±13.6) years. All patients were male. 5 patients were diagnosed as dilated cardiomyopathy, 2 patients as arrhythmogenic right ventricular cardiomyopathy and 1 patient as hypertrophic cardiomyopathy. The left ventricular ejection fraction was 37.8%±6.6%. After the treatment of R-SGB, 6 (75%) patients were free of electrical storm. 24 hours Holter monitoring showed significant reduction in ventricular tachycardia (VT) episodes from 43.0 (13.3, 276.3) to 1.0 (0.3, 34.0) on the first day following R-SGB (P<0.05) and 0.5 (0.0, 19.3) after whole R-SGB process (P<0.05). There were no procedure-related major complications. The mean follow-up was (4.8±1.1) months, and the median time of recurrent VT was 2 months. Conclusion: Minimally invasive R-SGB is a safe and effective method to treat electrical storm in patients with NICM.


Asunto(s)
Cardiomiopatías , Ablación por Catéter , Taquicardia Ventricular , Humanos , Masculino , Adulto , Persona de Mediana Edad , Anciano , Femenino , Volumen Sistólico , Ganglio Estrellado/cirugía , Función Ventricular Izquierda , Cardiomiopatías/terapia , Cardiomiopatías/complicaciones , Taquicardia Ventricular/terapia , Resultado del Tratamiento
3.
Zhonghua Jie He He Hu Xi Za Zhi ; 46(1): 51-55, 2023 Jan 12.
Artículo en Chino | MEDLINE | ID: mdl-36617929

RESUMEN

We reported the manifestations, auxiliary examination, and treatment courses of a case of scimitar syndrome with pulmonary sequestration containing carcinoma. The clinical characteristics of scimitar syndrome with pulmonary sequestration, pulmonary sequestration containing carcinoma were summarized based on the data of this case and the related literatures before January 2022. Scimitar syndrome can coexist with ipsilateral pulmonary sequestration. Because sequestered lung tissue has a risk of malignant transformation, a cancer screening test is useful for early diagnosis and timely treatment.


Asunto(s)
Secuestro Broncopulmonar , Carcinoma , Neoplasias Pulmonares , Venas Pulmonares , Síndrome de Cimitarra , Humanos , Secuestro Broncopulmonar/complicaciones , Síndrome de Cimitarra/complicaciones , Pulmón , Neoplasias Pulmonares/complicaciones , Carcinoma/complicaciones
5.
Zhonghua Yi Xue Za Zhi ; 102(8): 550-554, 2022 Mar 01.
Artículo en Chino | MEDLINE | ID: mdl-35196776

RESUMEN

Objective: To investigate the correlation and sex difference between obstructive sleep apnea hypopnea syndrome (OSAHS) and liver injury. Methods: A total of 974 OSAHS patients (444 cases of mild to moderate, 530 cases of severe) and 111 cases of simple snoring in the First Affiliated Hospital of Fujian Medical University and Zhangzhou Municipal Hospital from November 2015 to September 2019 were included in the study. The basic information of the patients was obtained through face-to-face survey with self-made questionnaire, physical examination, sleep monitoring and blood biochemical and liver function index detection were carried out among the included subjects. Multiple logistic regression model was used to analyze the correlation between OSAHS and liver injury and the gender differences. Results: The subjects were (50±14) years old, including 841 males (77.5%). Statistically significant differences in total cholesterol (TC), triglycerides (TG), low density lipoprotein-cholesterol (LDL-C), high density lipoprotein-cholesterol (HDL-C), fasting blood glucose, alamine aminotransferase (ALT), aspartate aminotransferase (AST), ALT/AST, gamma glutamyltransferase (GGT), the rate of elevated ALT, AST and liver injury were observed among the three groups (all P values<0.05). There was no significant difference in total bilirubin and ALP among all groups (all P values>0.05). Multivariate logistic regression showed that after adjusting for confounding factors, severe OSAHS was positively correlated with liver injury [OR (95%CI): 2.25 (1.22-4.14)]. Subgroup analysis by gender showed that severe OSAHS was positively correlated with liver injury in males [OR (95%CI): 2.20 (1.04-4.65)], but not in females, mild to moderate OSAHS [OR (95%CI): 1.56 (0.52-4.71)] or severe OSAHS [OR (95%CI): 2.07(0.64-6.75)], after adjusting for confounding factors. Conclusion: Severe OSAHS is positively correlated with liver injury in males, while female OSAHS is not associated with liver injury.


Asunto(s)
Apnea Obstructiva del Sueño , Adulto , Femenino , Humanos , Hígado , Masculino , Persona de Mediana Edad , Polisomnografía , Factores Sexuales , Apnea Obstructiva del Sueño/complicaciones , Ronquido
10.
J Endocrinol Invest ; 43(12): 1703-1710, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32266677

RESUMEN

PURPOSE: T4-binding globulin (TBG) is the main thyroid hormone (TH) transporter present in human serum. Inherited thyroxine-binding globulin (TBG) deficiency is caused by mutations in the TBG (SERPINA7) gene, which is located on the X chromosome. This study was performed to report and evaluate coding region mutations in TBG gene for partial thyroxine-binding globulin deficiency. METHODS: A pedigree spanning four generations is described in this study. The proband is a female with partial TBG deficiency. All members of this pedigree underwent thyroid function tests, while Sanger sequencing was used to identify the TBG gene mutations. Bioinformatics databases were used to evaluate the deleterious effects of the mutation(s). Two hundred and seven unrelated individuals were used to evaluate the thyroid function of individuals with different TBG mutations. A one-way ANOVA was used to analyze the impact of the TBG mutations on thyroid function. RESULTS: TBG gene sequencing results revealed that the proband had a novel mutation in codon 27 leading to alanine to valine substitution (p.A27V). This mutation was associated with lower serum T4 levels (p < 0.0001) when compared to the groups that did not carry the mutation. The previously reported p.L283F mutation was also found in the proband. The hemizygous p.L283F individuals presenting with lower T4 serum and TBG levels (p < 0.001) when compared to wildtype males and females. Both mutations were deleterious upon SIFT and PolyPhen-2 evaluation. CONCLUSION: Associated with partial thyroxine-binding globulin deficiency, this study reports a novel p.A27V mutation in the TBG gene.


Asunto(s)
Aborto Habitual/genética , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Globulina de Unión a Tiroxina/deficiencia , Adulto , China , Familia , Femenino , Enfermedades Genéticas Ligadas al Cromosoma X/complicaciones , Humanos , Mutación Missense , Sistemas de Lectura Abierta/genética , Linaje , Embarazo , Pruebas de Función de la Tiroides , Globulina de Unión a Tiroxina/genética
11.
Zhonghua Gan Zang Bing Za Zhi ; 27(9): 725-727, 2019 Sep 20.
Artículo en Chino | MEDLINE | ID: mdl-31594102

RESUMEN

Nonalcoholic fatty liver disease (NAFLD) is one of the common causes for chronic liver diseases, which progress gradually from nonalcoholic type simple fatty liver disease to hepatitis, cirrhosis and even liver failure and hepatocellular carcinoma. Sarcopenia is a progressive disease characterized by reduced skeletal muscle mass and function in association to metabolic dysfunctions. Recent studies have shown that the occurrence and development of NAFLD and sarcopenia are related, and there is a common base for the pathogenesis between the two, which may promote each other for mutual risk factors. This article reviews the current research progress of this field in order to clinically further understand the pathogenesis and intrinsic links between the two to look for appropriate interventions.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico/complicaciones , Sarcopenia/complicaciones , Carcinoma Hepatocelular , Humanos , Cirrosis Hepática , Neoplasias Hepáticas , Factores de Riesgo
12.
Eur Rev Med Pharmacol Sci ; 23(9): 3799-3805, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31115006

RESUMEN

OBJECTIVE: This study aims to investigate the expression levels and clinical significance of miR-503 and miR-375 in patients with esophageal squamous cell carcinoma. PATIENTS AND METHODS: 40 cases of cancer tissues and adjacent tissues in patients with esophageal squamous cell carcinoma were collected from March 2017 to September 2017 in the Department of Gastroenterology in the First Affiliated Hospital of Henan Polytechnic University. qRT-PCR was used to analyze the expressions of miR-503 and miR-375 in cancer tissues and adjacent normal tissues. The association between their expressions and the gender, age, degree of tumor differentiation, TNM staging, presence or absence of lymph node metastasis, and other clinicopathological characteristics of patients with esophageal squamous cell carcinoma was analyzed. RESULTS: The results showed that the expression level of miR-503 in esophageal squamous cell carcinoma tissues (6.83±2.14) was significantly higher than that in adjacent tissues (2.45±1.13). The expression level of miR-375 in esophageal squamous cell carcinoma tissues (3.75±1.06) was significantly lower than that in adjacent tissues (7.45±1.13). The expression levels of miR-503 and miR-375 in esophageal squamous cell carcinoma were related to the existence of lymph node metastasis, degree of differentiation of esophageal squamous cell carcinoma and TNM staging (p<0.001). There was no correlation between the expressions of miR-503 and miR-375 and the age, gender and tumor size of patients (p>0.05). CONCLUSIONS: miR-503 was highly expressed in esophageal squamous cell carcinoma and miR-375 was lowly expressed in esophageal squamous cell carcinoma. miR-503 and miR-375 were closely related to the lymphatic metastasis, degree of differentiation and TNM staging of the tumor.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , MicroARNs/metabolismo , Carcinoma de Células Escamosas/genética , Regulación hacia Abajo , Neoplasias Esofágicas/genética , Esófago/metabolismo , Esófago/patología , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias
13.
Clin Transl Oncol ; 21(5): 572-581, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30293229

RESUMEN

BACKGROUND: Obstructive sleep apnea (OSA) is associated with cancer incidence and mortality. The underlying mechanism is unclear. This study aims to evaluate the influence of intermittent hypoxia (IH), a novel hallmark of OSA, on tumor and to access the anti-tumor effect of endostatin on a mouse model with OSA. METHODS: The C57BL/6 J mice were randomly classified into four groups: control (normoxia) (CTL), control plus endostatin (CTL + ED), IH, and IH plus endostatin (IH + ED). Mice in IH and IH + ED groups were subjected to IH 8 h per day in 5 weeks. Lewis lung cancer cells were injected into the flank of each mouse after 1 week of IH exposure. Endostatin was also intraperitoneally injected after tumor volume reached about 200 mm3. The maximum standard uptake values (SUVmax) were detected by micro-positron emission tomography-computed tomography (micro-PET-CT) imaging prior and post-endostatin administration. Microvessel density (MVD) and vascular endothelial growth factor (VEGF) were determined for evaluating the anti-tumor effect of endostatin among the normoxia and IH conditions. RESULTS: Mice had higher SUVmax in the IH group than the CTL group (p < 0.01). When compared with mice in the CTL group, those in the IH group had significantly greater MVD values (p < 0.001). The SUVmax can be attenuated by endostatin both in the CTL (p < 0.01) and IH conditions (p < 0.001). When compared with CTL group, mice in the IH group had increased MVD values (p < 0.001) and VEGF expression both at mRNA (p < 0.05) and protein levels (p < 0.001 in western blotting results). Treatment with endostatin attenuated serum and tissue VEGF levels, lowering the MVD values. As compared to normoxia condition, the endostatin-therapeutic effects were more significant under the IH condition (p < 0.05 in western blotting results). CONCLUSIONS: Micro-PET-CT imaging is a promising non-invasive technique to evaluate the tumor metabolic characteristics under IH condition in vivo. The anti-tumor effect of endostatin under IH condition is superior to that of the normoxia condition.


Asunto(s)
Antineoplásicos/farmacología , Carcinoma Pulmonar de Lewis/tratamiento farmacológico , Modelos Animales de Enfermedad , Endostatinas/farmacología , Hipoxia/fisiopatología , Apnea Obstructiva del Sueño/complicaciones , Animales , Carcinoma Pulmonar de Lewis/etiología , Masculino , Ratones , Ratones Endogámicos C57BL , Células Tumorales Cultivadas
14.
Br J Radiol ; 85(1016): 1029-37, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22374276

RESUMEN

OBJECTIVE: To investigate the correlation between enhancement patterns of intrahepatic cholangiocarcinoma (ICC) on contrast-enhanced ultrasound (CEUS) and pathological findings. METHODS: The CEUS enhancement patterns of 40 pathologically proven ICC lesions were retrospectively analysed. Pathologically, the degree of tumour cell and fibrosis distribution in the lesion was semi-quantitatively evaluated. RESULTS: 4 enhancement patterns were observed in the arterial phase for 32 mass-forming ICCs: peripheral rim-like hyperenhancement (n=19); heterogeneous hyperenhancement (n=6); homogeneous hyperenhancement (n=3); and heterogeneous hypo-enhancement (n=4). Among the four enhancement patterns, the differences in tumour cell distribution were statistically significant (p<0.05). The hyperenhancing area on CEUS corresponded to more tumour cells for mass-forming ICCs. Heterogeneous hyperenhancement (n=2) and heterogeneous hypo-enhancement (n=2) were observed in the arterial phase for four periductal infiltrating ICCs. In this subtype, fibrosis was more commonly found in the lesions. Heterogeneous hyperenhancement (n=1) and homogeneous hyperenhancement (n=3) were observed in the arterial phase for four intraductal growing ICCs. This subtype tended to have abundant tumour cells. CONCLUSION: The CEUS findings of ICC relate to the degree of carcinoma cell proliferation at pathological examination. Hyperenhancing areas in the tumour always indicated increased density of cancer cells.


Asunto(s)
Neoplasias de los Conductos Biliares/diagnóstico por imagen , Conductos Biliares Intrahepáticos/patología , Colangiocarcinoma/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Adulto , Anciano , Neoplasias de los Conductos Biliares/patología , Colangiocarcinoma/patología , Medios de Contraste , Femenino , Humanos , Cirrosis Hepática/diagnóstico por imagen , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Fosfolípidos , Estudios Retrospectivos , Hexafluoruro de Azufre , Carga Tumoral , Ultrasonografía
15.
Eur J Neurol ; 18(8): 1060-6, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21244583

RESUMEN

BACKGROUND AND PURPOSE: Animal experiments indicate that the cerebral thrombin is associated with secondary brain damage after intracerebral hemorrhage (ICH). This study was aimed to investigate the concentrations of thrombin-antithrombin complex (TAT) in hematoma fluid and plasma of the patients with ICH after surgery and analyze the correlation between TAT complex levels and severity of ICH. METHODS: Sixty patients with ICH were enrolled. Craniotomy for removal of intracranial blood clot was performed within 24h after ICH. Hematoma fluid and plasma were collected on postoperative days 1, 2, and 4. The plasma obtained from healthy subjects and cerebrospinal fluid from patients without cerebrovascular diseases served as controls, respectively. Enzyme-linked immunosorbent assay was used to determine the concentrations of TAT complex in the patients and controls. RESULTS: TAT complex concentrations in both postoperative plasma and hematoma fluid of patients with ICH were significantly higher than those of the controls (P<0.01). In patients with ICH, hematoma fluid had a higher TAT complex level than plasma (P<0.01). The preoperative hemorrhage volume and postoperative TAT complex levels in plasma and hematoma fluid correlated positively with National Institutes of Health stroke scale and negatively with Glasgow coma score (P<0.01). CONCLUSION: This study indicates that TAT complex levels of plasma and hematoma fluid correlate positively with the severity of ICH. Determination of the plasma TAT complex concentration is helpful for the evaluation of the severity of post-ICH brain injury.


Asunto(s)
Hematoma/sangre , Hemorragia Intracraneal Hipertensiva/sangre , Péptido Hidrolasas/sangre , Adulto , Anciano , Anciano de 80 o más Años , Antitrombina III/líquido cefalorraquídeo , Femenino , Hematoma/cirugía , Humanos , Hemorragia Intracraneal Hipertensiva/cirugía , Hipertensión Intracraneal/sangre , Hipertensión Intracraneal/diagnóstico , Masculino , Persona de Mediana Edad , Péptido Hidrolasas/líquido cefalorraquídeo , Valor Predictivo de las Pruebas , Pronóstico
16.
Br J Radiol ; 83(989): 411-8, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19723766

RESUMEN

The aim of this study was to evaluate the imaging features of hepatic angiomyolipoma (AML) on contrast-enhanced ultrasound (CEUS). The imaging features of 12 pathologically proven hepatic AML lesions in 10 patients who had undergone baseline ultrasound (BUS) and CEUS examinations were evaluated retrospectively. The enhancement extent, pattern and dynamic change, along with the enhancement process, on CEUS were analysed. The diagnostic results of BUS and CEUS before pathological examination were also recorded. The results showed that 75% (9/12) of the AML lesions exhibited mixed echogenicity on BUS and most showed remarkable hyperechogenicity in combination with a hypoechoic or anechoic portion. Arterial flow signals were detected in 75% (9/12) of the lesions on colour Doppler imaging. On CEUS, 66.7% (n = 8) of the 12 lesions exhibited hyperenhancement in the arterial phase, slight hyperenhancement (n = 2) or isoenhancement (n = 6) in the portal phase, and slight hyperenhancement (n = 1) or isoenhancement (n = 7) in the late phase. Three (25%) lesions exhibited hyperenhancement in the arterial phase and hypoenhancement in both portal and late phases. One (8.3%) lesion exhibited hypoenhancement throughout the CEUS process. Before pathological examination with BUS, only 3 (25%) lesions were correctly diagnosed as hepatic AML. Conversely, on CEUS, correct diagnoses were made for 66.8% (8/12) of hepatic AMLs. Therefore, arterial hyperenhancement and subsequent sustained enhancement on CEUS were found in the majority of hepatic AMLs. The combination of BUS and CEUS leads to the correct diagnosis in the majority of hepatic AMLs, and is higher than the success rate achieved by BUS alone.


Asunto(s)
Angiomiolipoma/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Adulto , Medios de Contraste , Femenino , Humanos , Aumento de la Imagen , Masculino , Persona de Mediana Edad , Circulación Renal , Estudios Retrospectivos , Ultrasonografía Doppler en Color/métodos
17.
Br J Radiol ; 81(971): 881-9, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18941048

RESUMEN

The aim of this study was to compare the enhancement pattern of intrahepatic cholangiocarcinoma (ICC) on contrast-enhanced ultrasound (CEUS) with that on contrast-enhanced computed tomography (CECT). 40 pathologically proven ICC lesions in 40 patients were evaluated retrospectively with both CEUS and CECT. The enhancement level and pattern in the dynamic phases on both CEUS and CECT were analysed. The diagnostic results of CEUS and CECT before pathological examination were also recorded. During arterial phases, the number of lesions that appeared as (i) peripheral irregular rim-like hyperenhancement, (ii) diffuse heterogeneous hyperenhancement, (iii) diffuse homogeneous hyperenhancement and (iv) diffuse heterogeneous hypoenhancement were 19 (47.5%), 9 (22.5%), 5 (12.5%) and 7 (17.5%), respectively, on CEUS, and 22 (55.0%), 3 (7.5%), 2 (5.0%) and 13 (32.5%), respectively, on CECT (p = 0.125). In the portal phase, the number of lesions showing hyperenhancement and hypoenhancement were 1 (2.5%) and 39 (97.5%), respectively, on CEUS, and 15 (37.5%) and 25 (62.5%) on CECT (p = 0.0001). CEUS made a correct diagnosis in 32 (80.0%) lesions before pathological examination; CECT made a correct diagnosis in 27 (67.5%) lesions (p = 0.18). In conclusion, the enhancement patterns of ICC on CEUS were consistent with those on CECT in the arterial phase, whereas in the portal phase ICC faded out more obviously on CEUS than on CECT. CEUS had the same accuracy as CECT in diagnosing ICCs, and so can be used as a new modality for the characterization of ICC.


Asunto(s)
Neoplasias de los Conductos Biliares , Conductos Biliares Intrahepáticos , Colangiocarcinoma , Medios de Contraste , Adulto , Anciano , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Conductos Biliares Intrahepáticos/diagnóstico por imagen , Colangiocarcinoma/diagnóstico por imagen , Femenino , Hemodinámica/fisiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Tomografía Computarizada por Rayos X/normas , Resultado del Tratamiento , Ultrasonografía/métodos , Ultrasonografía/normas
18.
Phys Rev Lett ; 95(18): 185503, 2005 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-16383914

RESUMEN

The doping limit or the filling fraction limit (FFL) of various impurities for the intrinsic voids in the lattice of is studied by the density functional method. The FFL is shown to be determined not only by the interaction between the impurity and host atoms but also by the formation of secondary phases between the impurity atoms and one of the host atoms. The predicted FFLs for Ca, Sr, Ba, La, Ce, and Yb in are in excellent agreement with reported experimental data. A correlation between the FFL of an impurity atom and its valence state and electronegativity is discovered.

19.
J Environ Sci (China) ; 13(4): 453-8, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11723932

RESUMEN

The spatial variation of soil nutrients in topsoil (0-20 cm) was analyzed using semivariogram in the Zunhua County of Hebei Province, China. The effect on semivariogram with randomly deleted data and kriged estimates using various reduced sample sizes was also analyzed. The semivariograms of available N, total N, available P, organic matter were best described by a spherical model, except for available K, which best fitted a complex structure of exponential model and linear with sill model. The ratio of nugget to total sample variance ranged from 34.4% to 68.4%, indicating the spatial correlation of tested soil nutrients on a large scale was moderately dependent. Among five soil nutrients, available nitrogen and available phosphorus had the shortest spatial correlation range (5 km and 5.5 km), available K had the longest range (25.5 km), whereas total nitrogen and organic matter had intermediate spatial correlation range (14.5 km and 8.5 km). The semivariograms of available N, total N, available P, and organic matter were insensitive to a 50%-60% reduction in original sampling density, while for available K, it is up to 70%. The estimated spatial distributions of total N by kriging, under various reduced sample sizes, all correlated significantly (P = 0.001) with those obtained from original data. The results showed that the semivariogram was a relatively robust tool when used in a large region and sufficient spatial variation information could be retained regardless of a higher deletion proportion of the original data. The original sample data could be reduced by kriging and the estimates showed no loss of spatial information, however, the results may be unreliable unless a clearly identified semivariogram model could be obtained. The results may provide useful information for determining the appropriate sampling densities for these scales of soil survey.


Asunto(s)
Monitoreo del Ambiente , Geología/estadística & datos numéricos , Modelos Teóricos , Nitrógeno/análisis , Fósforo/análisis , Suelo , Compuestos Orgánicos/análisis
20.
Am J Chin Med ; 29(1): 155-60, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11321473

RESUMEN

The purpose of the study was to investigate the effects of two constituents of Panax notoginseng flower extract, Ginsenoside Rb2 and Rc, on human sperm motility and progression in vitro. Semen samples were collected from 20 patients with sperm motility between 20% and 40% of normal. All samples had sperm counts of over 20 million per milliliter, in accordance with the World Health Organization standard. Sperm were separated by a Percoll discontinuous gradient technique, and divided into a Percoll sperm control group, and three Ginsenoside Rb2 experimental groups (0.1, 0.01 and 0.001 mg/ml) and three Ginsenoside Rc experimental groups (0.1, 0.01 and 0.001 mg/ml). The results showed that at concentrations of 0.01 mg/ml and 0.001 mg/ml, Ginsenoside Rc enhanced both sperm motility and sperm progression significantly at the end of the 1st and 2nd hour. However, the three concentrations of Ginsenoside Rb2 did not increase sperm motility at the 1st or 2nd hour, but promoted sperm progression at the 2nd hour, when compared to the Percoll group.


Asunto(s)
Ginsenósidos , Panax , Plantas Medicinales , Saponinas/farmacología , Espermatozoides/efectos de los fármacos , Adulto , Humanos , Masculino , Extractos Vegetales , Recuento de Espermatozoides , Motilidad Espermática/efectos de los fármacos , Espermatozoides/fisiología
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