Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
J Comput Assist Tomogr ; 48(1): 143-149, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37551140

RESUMEN

OBJECTIVE: A prediction model of benign and malignant differentiation was established by magnetic resonance signs of parotid gland tumors to provide an important basis for the preoperative diagnosis and treatment of parotid gland tumor patients. METHODS: The data from 138 patients (modeling group) who were diagnosed based on a pathologic evaluation in the Department of Stomatology of Jilin University from June 2019 to August 2021 were retrospectively analyzed. The independent factors influencing benign and malignant differentiation of parotid tumors were selected by logistic regression analysis, and a mathematical prediction model for benign and malignant tumors was established. The data from 35 patients (validation group) who were diagnosed based on pathologic evaluation from September 2021 to February 2022 were collected for verification. RESULTS: Univariate and multivariate logistic regression analysis showed that tumor morphology, tumor boundary, tumor signal, and tumor apparent diffusion coefficient (ADC) were independent risk factors for predicting benign and malignant parotid gland tumors ( P < 0.05). Based on multivariate logistic regression analysis of the modeling group, a mathematical prediction model was established as follows: Y = the ex/(1 + ex) and X = 0.385 + (1.416 × tumor morphology) + (1.473 × tumor border) + (1.306 × tumor signal) + (2.312 × tumor ADC value). The results showed that the area under the receiver operating characteristic curve of the model was 0.832 (95% confidence interval, 0.75-0.91), the sensitivity was 82.6%, and the specificity was 70.65%. The validity of the model was verified using validation group data, for which the sensitivity was 85.71%, the specificity was 96.4%, and the correct rate was 94.3%. The results showed that the area under receiver operating characteristic curve was 0.936 (95% confidence interval, 0.83-0.98). CONCLUSIONS: Combined with tumor morphology, tumor ADC, tumor boundary, and tumor signal, the established prediction model provides an important reference for preoperative diagnosis of benign and malignant parotid gland tumors.


Asunto(s)
Neoplasias de la Parótida , Humanos , Neoplasias de la Parótida/diagnóstico por imagen , Neoplasias de la Parótida/patología , Estudios Retrospectivos , Nomogramas , Diagnóstico Diferencial , Imagen de Difusión por Resonancia Magnética/métodos , Sensibilidad y Especificidad , Glándula Parótida/diagnóstico por imagen , Glándula Parótida/patología
2.
Exp Ther Med ; 26(3): 456, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37614432

RESUMEN

Aggressive fibromatosis (AF), also known as ligamentoid fibromatosis and desmoid tumor, is a fibroblast clonoproliferative lesion located in the deep soft tissue. The present study reports the case of a 36-year-old female with AF who underwent cervical spinal cord ependymoma surgery. AF developed in the soft tissue of the neck adjacent to the incision site. The size of the neck AF increased rapidly over 2 years, and due to discomfort, the patient underwent initial surgical resection without any other combined treatment methods. When the patient was routinely reviewed at 6 months post-surgery, a recurrence of AF of the neck was found. The patient was recommended surgical resection and radiotherapy. This case report should improve the understanding of clinicians with regard to AF, and help the diagnostic process and treatment plan.

3.
BMC Oral Health ; 23(1): 548, 2023 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-37559074

RESUMEN

BACKGROUND: The purpose of this study was to identify neurogenic tumours and pleomorphic adenomas of the parapharyngeal space based on the texture characteristics of MRI-T2WI. METHODS: MR findings and pathological reports of 25 patients with benign tumours in the parapharyngeal space were reviewed retrospectively (13 cases with pleomorphic adenomas and 12 cases with neurogenic tumours). Using PyRadiomics, the texture of the region of interest in T2WI sketched by radiologists was analysed. By using independent sample t-tests and Mann‒Whitney U tests, the selected texture features of 36 Gray Level Co-Occurrence Matrix (GLCM) and Gray Level Dependence Matrix (GLDM) were tested. A set of parameters of texture features showed statistically significant differences between the two groups, which were selected, and the diagnostic efficiency was evaluated via the operating characteristic curve of the subjects. RESULTS: The differences in the three parameters - small dependence low level emphasis (SDLGLE), low level emphasis (LGLE) and difference variance (DV) of characteristics - between the two groups were statistically significant (P < 0.05). No significant difference was found in the other indices. ROC curves were drawn for the three parameters, with AUCs of 0.833, 0.795, and 0.744, respectively. CONCLUSIONS: There is a difference in the texture characteristic parameters based on magnetic resonance T2WI images between neurogenic tumours and pleomorphic adenomas in the parapharyngeal space. For the differential diagnosis of these two kinds of tumours, texture analysis of significant importance is an objective and quantitative analytical tool.


Asunto(s)
Adenoma Pleomórfico , Humanos , Adenoma Pleomórfico/diagnóstico por imagen , Adenoma Pleomórfico/patología , Estudios Retrospectivos , Espacio Parafaríngeo/patología , Imagen por Resonancia Magnética , Diagnóstico Diferencial
4.
Diabetes Metab Syndr Obes ; 16: 2177-2186, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37521748

RESUMEN

Objective: To explore the value of 1.5T magnetic resonance (MR) fat saturation-T2-weighted imaging (FS-T2WI) and apparent diffusion coefficient (ADC) imaging texture features in distinguishing the renal changes of patients with stage III type 2 diabetic kidney disease (DKD) from healthy people. Methods: This study collected 55 patients with stage III DKD (39 males and 16 females) and 33 healthy controls (13 males and 20 females) from December 2021 to June 2022 in the China-Japan Union Hospital of Jilin University. All subjects were randomly divided in a ratio of 6:4 to extract and screen the FS-T2WI and ADC texture features of the right kidney of the subjects. The area under the curve (AUC) was used to assess the diagnostic accuracy of each model. Results: There were significant differences between urea, creatinine and sex (p<0.05) of the two groups in the training and test set, and no significant difference in age and body mass index (BMI). We extracted 1409 imaging features from the original ADC sequence and selected them by wavelet and Laplace-Gaussian filter and LASSO algorithm, and using the same methods of FS-T2WI. Finally, FS-T2WI and ADC models were selected to construct the united model, including 3 first-order features and 8 texture features. The AUC values of the training set of FS-T2WI, ADC, FS-T2WI+ADC combined logistic regression model were 0.96, 0.91, 0.98; the AUC values of the test set were 0.91, 0.89 and 0.93, and the specificity and accuracy values of the united model were 0.90 and 0.89, respectively. Conclusion: FS-T2WI and ADC imaging features based on 1.5 T MR had diagnostic value in the early diagnosis of DKD stage III, and the combined model of FS-T2WI and ADC had high diagnostic efficiency.

5.
Sci Adv ; 9(21): eadg1258, 2023 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-37224258

RESUMEN

Plant cell walls represent the most abundant pool of organic carbon in terrestrial ecosystems but are highly recalcitrant to utilization by microbes and herbivores owing to the physical and chemical barrier provided by lignin biopolymers. Termites are a paradigmatic example of an organism's having evolved the ability to substantially degrade lignified woody plants, yet atomic-scale characterization of lignin depolymerization by termites remains elusive. We report that the phylogenetically derived termite Nasutitermes sp. efficiently degrades lignin via substantial depletion of major interunit linkages and methoxyls by combining isotope-labeled feeding experiments and solution-state and solid-state nuclear magnetic resonance spectroscopy. Exploring the evolutionary origin of lignin depolymerization in termites, we reveal that the early-diverging woodroach Cryptocercus darwini has limited capability in degrading lignocellulose, leaving most polysaccharides intact. Conversely, the phylogenetically basal lineages of "lower" termites are able to disrupt the lignin-polysaccharide inter- and intramolecular bonding while leaving lignin largely intact. These findings advance knowledge on the elusive but efficient delignification in natural systems with implications for next-generation ligninolytic agents.


Asunto(s)
Ecosistema , Isópteros , Animales , Isópteros/genética , Lignina , Madera , Carbono
6.
Front Endocrinol (Lausanne) ; 13: 846407, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35600605

RESUMEN

Objective: The objective of the study was to explore the value of MRI texture features based on T1WI, T2-FS and diffusion-weighted imaging (DWI) in differentiation of renal changes in patients with stage III type 2 diabetic nephropathy (DN) and normal subjects. Materials and Methods: A retrospective analysis was performed to analyze 44 healthy volunteers (group A) and 40 patients with stage III type 2 diabetic nephropathy (group B) with microalbuminuria. Urinary albumin to creatinine ratio (ACR) <30 mg/g, estimated glomerular filtration rate (eGFR) in the range of 60-120 ml/(min 1.73 m2), and randomly divided into primary cohort and test cohort. Conventional MRI and DWI of kidney were performed using 1.5 T magnetic resonance imaging (MRI). The outline of the renal parenchyma was manually labeled in fat-suppressed T2-weighted imaging (FS-T2WI), and PyRadiomics was used to extract radiomics features. The radiomics features were then selected by the least absolute shrinkage and selection operator (LASSO) method. Results: There was a significant difference in sex and body mass index (BMI) (P <0.05) in the primary cohort, with no significant difference in age. In the final results, the wavelet and Laplacian-Gaussian filtering are used to extract 1,892 image features from the original T1WI image, and the LASSO algorithm is used for selection. One first-order feature and six texture features are selected through 10 cross-validations. In the mass, 1,638 imaging extracts features from the original T2WI image.1 first-order feature and 5 texture features were selected. A total of 1,241 imaging features were extracted from the original ADC images, and 5 texture features were selected. Using LASSO-Logistic regression analysis, 10 features were selected for modeling, and a combined diagnosis model of diabetic nephropathy based on texture features was established. The average unit cost in the logistic regression model was 0.98, the 95% confidence interval for the predictive efficacy was 0.9486-1.0, specificity 0.97 and precision 0.93, particularly. ROC curves also revealed that the model could distinguish with high sensitivity of at least 92%. Conclusion: In consequence, the texture features based on MR have broad application prospects in the early detection of DN as a relatively simple and noninvasive tool without contrast media administration.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Nefropatías Diabéticas/diagnóstico por imagen , Humanos , Riñón/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos
7.
BMC Oral Health ; 21(1): 585, 2021 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-34798867

RESUMEN

BACKGROUND: Tongue squamous cell carcinoma (TSCC) is one of the most difficult malignancies to control. It displays particular and aggressive behaviour even at an early stage. The purpose of this paper is to explore the value of radiomics based on magnetic resonance fat-suppressed T2-weighted images in predicting the degree of pathological differentiation of TSCC. METHODS: Retrospective analysis of 127 patients with TSCC who were randomly divided into a primary cohort and a test cohort, including well-differentiated, moderately differentiated and poorly differentiated. The tumour regions were manually labelled in fat-suppressed T2-weighted imaging (FS-T2WI), and PyRadiomics was used to extract radiomics features. The radiomics features were then selected by the least absolute shrinkage and selection operator (LASSO) method. The model was established by the logistic regression classifier using a 5-fold cross-validation method, applied to all data and evaluated using the area under the receiver operating characteristic curve (AUC), accuracy, sensitivity and specificity. RESULTS: In total, 1132 features were extracted, and seven features were selected for modelling. The AUC in the logistic regression model for well-differentiated TSCC was 0.90 with specificity and precision values of 0.92 and 0.78, respectively, and the sensitivity for poorly differentiated TSCC was 0.74. CONCLUSIONS: The MRI-based radiomics signature could discriminate between well-differentiated, moderately differentiated and poorly differentiated TSCC and might be used as a biomarker for preoperative grading.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de la Lengua , Carcinoma de Células Escamosas/diagnóstico por imagen , Diferenciación Celular , Humanos , Imagen por Resonancia Magnética , Estudios Retrospectivos , Lengua , Neoplasias de la Lengua/diagnóstico por imagen
8.
Ann Palliat Med ; 10(9): 10062-10074, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34551578

RESUMEN

OBJECTIVE: In this review, we aim to provide an overview of the imaging techniques most commonly used to study Alzheimer's disease (AD). BACKGROUND: Neuroimaging biomarkers can be used to evaluate these abnormalities, improve the ability of early diagnosis and help predict disease progression. These signs mainly include local brain atrophy on structural MRI, hypometabolic foci, and amyloid plaque deposition in the brain detected by specific imaging. These techniques not only have their unique advantages, but can complement each other in multimodal imaging evaluation of patients with cognitive impairment and dementia. METHODS: A literature search was performed on PubMed using the search term combinations "Alzheimer's disease", "Amyloid-beta plaques", and "MRI". We discuss various magnetic resonance imaging (MRI) based techniques, including direct imaging, indirect imaging, amyloid-beta (Aß) plaque and radiomics, Hybrid PET/MRI and MRI imaging technology in the future, placing a special emphasis on multimodal imaging, and focus our review on the MRI features of Aß plaques (AD biomarkers). CONCLUSIONS: After a lot of research and reasonable selection, multimodal imaging composed of MRI and PET can significantly improve the diagnosis and treatment of AD patients, and the complementary information can be obtained by the new PET/MR instrument at the same time. The findings of this review emphasize that multimodal imaging is likely to be the preferred method for future AD research and clinical practice.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Enfermedad de Alzheimer/diagnóstico por imagen , Disfunción Cognitiva/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Neuroimagen , Placa Amiloide/diagnóstico por imagen
9.
BMC Oral Health ; 21(1): 463, 2021 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-34556116

RESUMEN

BACKGROUND: To research the first-order features of apparent diffusion coefficient (ADC) values on diffusion-weighted magnetic resonance imaging (DWI) in maxillofacial malignant mesenchymal tumours. METHODS: The clinical data of 12 patients with rare malignant mesenchymal tumours of the maxillofacial region (6 cases of sarcoma and 6 cases of lymphoma) treated in the hospital from May 2018 to June 2020 and were confirmed by postoperative pathology were retrospectively analyzed. The patients were all examined by 1.5T magnetic resonance imaging. PyRadiomics were used to extract radiomics imaging first-order features. Group differences in quantitative variables were examined using independent-samples t-tests. RESULTS: The voxels number of ADCmean and ADCmedian of sarcoma tissues were 44.9124 and 44.2064, respectively, significantly higher than those in lymphoma tissues (ADCmean (- 68.8379) and ADCmedian (- 74.0045)), the difference considered statistically significant, so do the ADCkurt and ADCskew. CONCLUSIONS: The statistical difference of ADCmean and ADCmedian is significant, it is consistent with the outcome of the manual measurement of the ADC mean value of the most significant cross-section of twelve cases of lymphoma. Development of tumour volume based on the ADC parameter map of DWI demonstrates that the first-order ADC radiomics features analysis can provide new imaging markers for the differentiation of maxillofacial sarcoma and lymphoma. Therefore, first-order ADC features of ADCkurt combined ADCskew may improve the diagnosis level.


Asunto(s)
Linfoma , Sarcoma , Imagen de Difusión por Resonancia Magnética , Humanos , Linfoma/diagnóstico por imagen , Imagen por Resonancia Magnética , Estudios Retrospectivos , Sarcoma/diagnóstico por imagen
10.
J Med Entomol ; 56(1): 29-34, 2019 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-30304503

RESUMEN

Abelia chinensis R. Br. (Dipsacales: Caprifoliaceae) is one of the preferred nectar host plants for Culex pipiens pallens Coquillett (Diptera: Culicidae). However, the volatile compounds of its flowers that might be involved in directing mosquitoes' orientation to its nectaries remain unknown. In the present study, the volatile compounds released by A. chinensis florets were collected by solid phase microextraction fiber and analyzed by gas chromatography-mass spectrometry system. Based on the major component species in the volatile profile, a synthetic phytochemical blend (Blend B, composed of six compounds at their most attractive concentrations) was formulated, and its attractiveness was tested against the pentane extract of A. chinensis florets at most attractive concentration (Blend A) and a formerly developed synthetic phytochemical blend (Blend C) in the olfactometer, respectively. The results revealed that the volatile profile of A. chinensis florets was mainly composed of aromatic compounds, most of which had been reported to be attractive to other mosquito species. The synthetic Blend B was as attractive as Blend A (10-1-fold of the crude pentane extract) in the olfactometer bioassays, but they were not as attractive as the formerly developed Blend C. The present study indicated that quantitative and qualitative differences in the constituents of phytochemical blends could significantly affect their attractiveness to Cx. pipiens pallens, and the capture efficiency of phytochemical attractants deserves further research before being applied in the field.


Asunto(s)
Caprifoliaceae/química , Culex , Feromonas/análisis , Compuestos Orgánicos Volátiles/análisis , Animales , Conducta Apetitiva , Femenino , Flores/química , Sesquiterpenos Policíclicos/análisis
11.
J Med Entomol ; 55(4): 787-794, 2018 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-29566214

RESUMEN

Efforts to develop mosquito attractants using vertebrate host volatiles have been well made under laboratory conditions but their attractiveness to mosquitoes in the wild still needs to be evaluated. In the present study, we evaluated the attraction of female Culex pipiens pallens Coquillett (Diptera: Culicidae) to 11 individual chemical compounds found in vertebrate host odors, and to synthetic blends, consisting of different combinations of the compounds. These tests were conducted under laboratory and field conditions using a Y-tube olfactometer and odor-baited traps, respectively. When delivered at concentrations ranging from 0.1 to 10.0 µg/kg, 9 of the 11 compounds were attractive to female mosquitoes under laboratory conditions. We developed 47 synthetic blends composed of the 6 most attractive compounds (propionic acid, hexanal, myristic acid, benzaldehyde, 1-octen-3-ol, and geranyl acetone) and 18 of them were significantly attractive to mosquitoes in the olfactometer. Most of the attractive blends contained two to four attractive compounds. In the field, 5 of the 18 blends captured significantly more mosquitoes than did control traps. The findings demonstrate that female mosquitoes can be attracted by single chemical compounds as well as some of their synthetic blends. The effectiveness of synthetic blends depended on specific combinations of several compounds, rather than simply increasing the number of attractive compounds in the blends. Synthetic blends may have potential for use in odor-baited traps for mosquito surveillance.


Asunto(s)
Quimiotaxis , Culex/fisiología , Control de Mosquitos/métodos , Odorantes , Animales , Femenino , Olfatometría
12.
Parasitol Res ; 117(1): 67-73, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29177970

RESUMEN

Mosquito adults usually need to ingest sugar from nectar host plants to sustain their metabolic needs. Mosquitoes could be differentially attracted by various flowering plant species, and the volatiles were thought to be important factors attributed to the differential attractiveness. However, whether mosquitoes' preference for host plants correlates with their nutritional rewards from sugar sources remains unclear. In the present study, the preference of newly emerged Culex pipiens pallens to three kinds of flowering plants (Ligustrum quihoui, Abelia chinensis, and Nerium indicum) was determined in the olfactometer. Besides, when the newly emerged mosquitoes were provided with these flowering plants as sugar sources, the content of their metabolic reserves (glycogen, lipid, and protein) was determined. The results revealed that Cx. pipiens pallens could be differentially attracted by the odors emitted by the inflorescences of the tested flowering plants, and the nutritional rewards of mosquitoes were significantly affected by feeding on different inflorescences. The present study demonstrated that feeding on nectar host plants with differential attraction could affect the energy reserves of Cx. pipiens pallens.


Asunto(s)
Culex/fisiología , Flores , Animales , Culex/metabolismo , Metabolismo Energético , Conducta Alimentaria , Preferencias Alimentarias , Odorantes , Semillas
13.
Acta Trop ; 163: 20-5, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27456936

RESUMEN

Mosquito adults usually need to obtain sugar from floral nectaries and damaged fruits/seed pods to replenish their energy reserves. The newly developed attractive toxic sugar baits have been successfully applied in controlling various mosquito species outdoors. However, the attraction of Culex pipiens pallens to different fruit-based sugar baits remains unknown. In the present study, we selected nine common fruit species, prepared the fruit-based sugar solutions, and investigated the attractiveness of different sugar baits to newly emerged Cx. pipiens pallens in the laboratory. The results showed that when tested against the 5% brown sugar solution, all the sugar baits were significantly attractive to both females and males. When tested together in the mesh-covered cage, there was a significant difference on the attractiveness between different fruit-based sugar baits. The most attractive fruit species included Broussonetia papyrifera, Cucumis melo, C. melo var. saccharinus, Amygdalus persica and Pyrus bretschneideri, and their seed pods could be potentially used as ingredients in ATSB for controlling mosquitoes outdoors.


Asunto(s)
Culex/fisiología , Frutas , Insectos Vectores/fisiología , Control de Mosquitos/métodos , Animales , Conducta Alimentaria , Femenino , Masculino
14.
Acta Trop ; 155: 51-7, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26739652

RESUMEN

Adult mosquitoes rely on ingestion of sugar from plants to survive, swarm and mate. Culex pipiens pallens Coguillett is the primary vector of lymphatic filariasis and epidemic encephalitis. Little is known about the effect of feeding on different sugar sources on the survivorship and fecundity of Cx. pipiens pallens. In the present study, newly emerged mosquitoes were exposed to several flowering plant and seed pod species with different olfactory preferences, and the survival times of mosquitoes exposed to these sugar sources were determined. The proportions of mosquitoes that ingested sugar from host plants were investigated by cold anthrone tests. The numbers of eggs per egg raft laid by mosquitoes were compared when they were provided with different sugar sources and one blood meal. The results revealed that feeding on different kinds of sugar sources significantly affected female and male mosquitoes' survival times. Cold anthrone tests indicated that the proportions of sugar-positive mosquitoes from different nutritional regimes within 24h corresponded to the preference rankings of Cx. pipiens pallens to these sugar sources, and rapid declines in the proportions of surviving individuals might be attributed to their insufficient ingestion of sugar from nutritional regimes. Feeding on different sugar sources strongly affected the proportions of engorged mosquitoes, and females that had fed on their preferred sugar sources laid more eggs than mosquitoes provided with less preferred sugar sources. The results would provide insights in developing mosquito control strategies that target the sugar feeding behavior of mosquitoes.


Asunto(s)
Culex/fisiología , Insectos Vectores/fisiología , Animales , China/epidemiología , Encefalitis/epidemiología , Conducta Alimentaria/fisiología , Femenino , Fertilidad , Filariasis/epidemiología , Flores , Humanos , Masculino , Semillas , Tasa de Supervivencia
15.
Parasit Vectors ; 8: 598, 2015 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-26577584

RESUMEN

BACKGROUND: Most mosquito species need to obtain sugar from host plants. Little is known about the chemical cues that Culex pipiens pallens use during their orientation to nectar host plants. In this study, we investigated the behavioural responses of female Cx. pipiens pallens to common floral scent compounds and their blends. METHODS: Behavioural responses of female Cx. pipiens pallens to 18 individual compounds at different concentrations were determined in the olfactometer bioassays. A synthetic blend composed of behaviourally active compounds was formulated, and its attractiveness to mosquitoes was tested. Several most attractive compounds constituted a reduced blend, and its attractiveness was tested against the solvent and the full blend, respectively. Mosquito response in the olfactometer was analyzed by comparing the percentages of mosquitoes caught in the two arms by χ(2) test (observed versus expected). RESULTS: Fifteen of the 18 compounds were attractive to female Cx. pipiens pallens in the dose-dependent bioassays, with the exception of ß-pinene, acetophenone and nonanal. (68.00 ± 2.49) % mosquitoes responded to the full blend composed of these 15 compounds on their optimal doses when tested against the solvent, with the preference index at 46.11 ± 3.57. Six individual compounds whose preference indices were over 40 constituted the reduced blend, and it attracted (68.00 ± 1.33) % mosquitoes when tested against the solvent while its preference index was 42.00 ± 3.54. When tested against the full blend simultaneously in the olfactometer, the reduced blend could attract (45.00 ± 2.69) % of released mosquitoes, which was as attractive as the full blend. CONCLUSIONS: Our results demonstrate that female Cx. pipiens pallens is differentially attracted by a variety of compounds at different concentrations. Alteration of the concentration strongly affects the attractiveness of the synthetic blend. Several floral scent volatiles might be the universal olfactory cues for various mosquito species to locate their nectar host plants, which could be potentially used in trapping devices for surveillance and control of them.


Asunto(s)
Conducta Animal/efectos de los fármacos , Culex/efectos de los fármacos , Culex/fisiología , Feromonas/farmacología , Fitoquímicos/farmacología , Compuestos Orgánicos Volátiles/farmacología , Animales , Femenino
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(1): 1-4, 2007 Jan.
Artículo en Chino | MEDLINE | ID: mdl-17390634

RESUMEN

Intensity parameters of Pr3+ in ZBLAN glass were calculated using Judd-Ofelt(J-O) theory with absorption spectrum measurement. The anomalous behavior of Pr3+ was discussed using J-O theory. Base on the intensity parameters, the optical parameters such as spontaneous emission rate, branching ratio, and integrated emission cross section etc were predicted. The future of the glass as a laser material was discussed, and the probability of photon avalanche in the material was also analysed.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA