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排序方式: 共有71条查询结果,搜索用时 19 毫秒
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Ovarian follicular dynamics and fluctuations in fat body, oviducal, and liver masses were studied in captive Rana cyanophlyctis in comparison with wild-caught frogs, sampled at monthly intervals over a period of 12 months. In both the captive and wild-caught frogs first growth phase (FGP) and second growth phase (SGP) or vitellogenic oocytes were produced throughout the period examined; however, changes in ovarian and oviducal weights were less marked in the former group. In the captive frogs SGP oocyte production was reduced by 50%, and, maximum ovarian weight and SGP oocyte number were attained 2-3 months earlier than in wild-caught controls. The FGP oocyte pool in laboratory-maintained frogs, however, was comparable with that of the corresponding wild-caught frogs. Captivity caused a threefold increase in atresia and reduced the number of oocytes reaching SGP. The depletion of fat stores in fat bodies during the later phases of captivity suggests that the deposition of lipids into oocytes (for SGP) was given priority over storage in the fat bodies. The low oviducal weights of captive frogs was correlated with a reduced number of SGP oocytes, which are the source of estrogen. On the other hand, liver weight remained high, indicating adequate hepatic vitellogenin synthesis. Possible reduction in its output was not detected, possibly due to the reduced number of follicles reaching SGP. The findings indicate that stress of captivity decreases gonadotrophins and estrogen levels. Oviducal growth is reduced in captive frogs.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
A Puri R Sethi B Singh SK Dwivedi VS Narain RK Saran VK Puri 《Indian pacing and electrophysiology journal》2009,9(3):186-189
A 25-year-old previously asymptomatic pregnant woman at 36 weeks'' gestation was noticed to have repetitive monomorphic ventricular tachycardia. A dilated left ventricle with moderately reduced systolic function was found on echocardiographic examination. This is a very rare presentation of peripartum cardiomyopathy (PPCMP) presenting with repetitive monomorphic ventricular tachycardia. 相似文献
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KB Cullberg T Christiansen SK Paulsen JM Bruun SB Pedersen B Richelsen 《Obesity (Silver Spring, Md.)》2013,21(3):454-460
Background:
Vascular growth is a prerequisite for adipose tissue (AT) development and expansion. Some AT cytokines and hormones have effects on vascular development, like vascular endothelial growth factor (VEGF‐A), angiopoietin (ANG‐1), ANG‐2 and angiopoietin‐like protein‐4 (ANGPTL‐4).Methods:
In this study, the independent and combined effects of diet‐induced weight loss and exercise on AT gene expression and proteins levels of those angiogenic factors were investigated. Seventy‐nine obese males and females were randomized to: 1. Exercise‐only (EXO; 12‐weeks exercise without diet‐restriction), 2. Hypocaloric diet (DIO; 8‐weeks very low energy diet (VLED) + 4‐weeks weight maintenance diet) and 3. Hypocaloric diet and exercise (DEX; 8‐weeks VLED + 4‐weeks weight maintenance diet combined with exercise throughout the 12 weeks). Blood samples and fat biopsies were taken before and after the intervention.Results:
Weight loss was 3.5 kg in the EXO group and 12.3 kg in the DIO and DEX groups. VEGF‐A protein was non‐significantly reduced in the weight loss groups. ANG‐1 protein levels were significantly reduced 22‐25% after all three interventions (P < 0.01). The ANG‐1/ANG‐2 ratio was also decreased in all three groups (P < 0.05) by 27‐38%. ANGPTL‐4 was increased in the EXO group (15%, P < 0.05) and 9% (P < 0.05) in the DIO group. VEGF‐A, ANG‐1, and ANGPTL‐4 were all expressed in human AT, but only ANGPTL‐4 was influenced by the interventions.Conclusions:
Our data show that serum VEGF‐A, ANG‐1, ANG‐2, and ANGPTL‐4 levels are influenced by weight changes, indicating the involvement of these factors in the obese state. Moreover, it was found that weight loss generally was associated with a reduced angiogenic activity in the circulation. 相似文献5.
Tumor infiltrating lymphocytes (TIL), especially T-cells, have both prognostic and therapeutic applications. The presence of CD8+ effector T-cells and the ratio of CD8+ cells to FOXP3+ regulatory T-cells have been used as biomarkers of disease prognosis to predict response to various immunotherapies. Blocking the interaction between inhibitory receptors on T-cells and their ligands with therapeutic antibodies including atezolizumab, nivolumab, pembrolizumab and tremelimumab increases the immune response against cancer cells and has shown significant improvement in clinical benefits and survival in several different tumor types. The improved clinical outcome is presumed to be associated with a higher tumor infiltration; therefore, it is thought that more accurate methods for measuring the amount of TIL could assist prognosis and predict treatment response. We have developed and validated quantitative immunohistochemistry (IHC) assays for CD3, CD8 and FOXP3 for immunophenotyping T-lymphocytes in tumor tissue. Various types of formalin fixed, paraffin embedded (FFPE) tumor tissues were immunolabeled with anti-CD3, anti-CD8 and anti-FOXP3 antibodies using an IHC autostainer. The tumor area of stained tissues, including the invasive margin of the tumor, was scored by a pathologist (visual scoring) and by computer-based quantitative image analysis. Two image analysis scores were obtained for the staining of each biomarker: the percent positive cells in the tumor area and positive cells/mm2 tumor area. Comparison of visual vs. image analysis scoring methods using regression analysis showed high correlation and indicated that quantitative image analysis can be used to score the number of positive cells in IHC stained slides. To demonstrate that the IHC assays produce consistent results in normal daily testing, we evaluated the specificity, sensitivity and reproducibility of the IHC assays using both visual and image analysis scoring methods. We found that CD3, CD8 and FOXP3 IHC assays met the fit-for-purpose analytical acceptance validation criteria and that they can be used to support clinical studies. 相似文献
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A viable option for increasing nitrogen (N) use efficiency and mitigation of negative impacts of N on the environment is to capitalize on multi-element interactions through implementation of nutrient management programs that provide balanced nutrition. Numerous studies have demonstrated the immediate efficacy of this approach in the developing regions like China and India as well as developed countries in North America. Based on 241 site-years of experiments in these countries, the first-year N recovery efficiency (RE) for the conventional or check treatments averaged 21% while the balanced treatments averaged 54% RE, for an average increase of 33% in RE due to balanced nutrition. Effective policies to promote adoption are most likely those that enable site-specific approaches to nutrient management decisions rather than sweeping, nation-wide incentives supporting one nutrient over another. Local farmers, advisers and officials need to be empowered with tools and information to help them define necessary changes in practices to create more balanced nutrient management. 相似文献
8.
Taxonomic relationships within the pan-oriental narrow-mouth toad Microhyla ornata as revealed by mtDNA analysis (Amphibia, Anura, Microhylidae) 总被引:2,自引:0,他引:2
Matsui M Ito H Shimada T Ota H Saidapur SK Khonsue W Tanaka-Ueno T Wu GF 《Zoological science》2005,22(4):489-495
A molecular phylogenetic survey was conducted using mtDNA sequences of 12S and 16S rRNA, and cyt-b genes to examine taxonomic relationships among populations of the Pan-Oriental microhylid, Microhyla ornata, from India, Bangladesh, Thailand, Laos, China, Taiwan, and the Ryukyu Archipelago of Japan. Two discrete clades are recognized within this species, one consisting of populations from India and Bangladesh, and the other encompassing the remaining populations. In the latter clade, populations from the Ryukyu Archipelago are clearly split from the rest (populations from Taiwan and the continent) with considerable degrees of genetic differentiations. Each of the three lineages is judged to represent a good species, and the name Microhyla ornata is restricted to the South Asian populations. For the populations from Taiwan and a wide region from China to Southeast Asia, the name Microhyla fissipes should be applied, whereas the Ryukyu populations are most appropriately referred to as Microhyla okinavensis, although further substantial genetic differentiations are recognized among some island group populations within this last species. 相似文献
9.
Narahari P. Gramapurohit Dheeraj K. Veeranagoudar Shivangouda V. Mulkeegoudra Bhagyashri A. Shanbhag Srinivas K. Saidapur 《Journal of Ethology》2006,24(3):267-274
Ontogenetic changes in kin-recognition behavior, effect of social environment on kin-recognition ability, and use of visual and chemical cues in kin recognition have been studied in tadpoles of Bufo scaber after rearing them with kin, in mixed groups, or in isolation from Gosner stage 12 (gastrula). By use of a rectangular choice tank the tadpoles were tested for their ability to choose between (a) familiar siblings and unfamiliar non-siblings, (b) unfamiliar siblings and familiar non-siblings, and (c) unfamiliar siblings and unfamiliar non-siblings. When tested without any stimulus groups in the end compartments of the tank, random distribution was observed for the tadpoles and no bias for the apparatus or the procedure. In the presence of kin and non-kin in the end compartments, significantly more tadpoles spent most of their time near kin (familiar or unfamiliar) rather than near non-kin during early larval stages, up to stage 37. After stage 37 (characterized by the differentiation of toes), test tadpoles showed no preference to associate with kin, suggesting an ontogenetic shift in the kin-recognition ability in B. scaber. In experiments involving selective blockade of visual or chemical cues the test tadpoles preferentially associated near their kin on the basis of chemical rather than visual cues. These findings suggest that familiarity with siblings is not necessary for kin recognition and that kin-recognition ability is not modified after exposure to non-kin by mixed rearing. The findings for B. scaber indicate a self referent phenotype matching mechanism of kin recognition which is predominantly aided by chemical rather than visual cues. 相似文献
10.