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181.
Tourmente M Cardozo GA Guidobaldi HA Giojalas LC Bertona M Chiaraviglio M 《Research in veterinary science》2007,82(1):93-98
Semen quality analysis constitutes a powerful tool to evaluate the fertility potential of males in threatened species. The Argentine boa constrictor or lampalagua (Boa constrictor occidentalis) is a threatened snake species and has been included in Appendix I of CITES. The objective of this work is to characterize the sperm of B. c. occidentalis on the bases of dynamic parameters to improve this species conservation. Dynamic parameters were measured in sperm samples using videomicroscopy and image analysis software. The sperm population showed a high degree of heterogeneity in velocity parameter values and 95% of the cells showed a linear pattern of movement. Studies in other species indicate that the number of motile spermatozoa and their movement speed is directly correlated with fertilization success. This work will help to establish basic parameter values for the evaluation of the reproductive potential of populations of B. c. occidentalis and to resolve questions referred to its reproductive strategies. 相似文献
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183.
AIM:To explore the analgesic effect of active component from cobra venom in Wannan area. METHODS:The active component was purified from crude venom of cobra by cation-exchange chromatography and size-exclusion chromatography. The purity and molecular weight of the active component were determined by SDS-polyacrylamide gel electrophoresis and capillary zone electrophoresis. The analgesic activity was analyzed by hot-plate test and acetic acid writhing test. Normal saline and morphine were used as controls. RESULTS:A single active component was obtained from crude cobra venom. The molecular weight was about 6 500 D. The analgesic effect of the active component persisted from 0.5 h to 8 h after hot-plate test. With intraperitoneal injection of the active component at doses of 0.03 mg/kg, 0.1 mg/kg and 0.3 mg/kg in mice, the writhing inhibition rates were 27%, 50% and 70%, respectively. No statistical difference between 0.3 mg/kg group and morphine group was observed. CONCLUSION:The active component from crude cobra venom has a dose-dependent analgesic effect. 相似文献
184.
寄生蜂毒液蛋白的研究进展 总被引:7,自引:0,他引:7
寄生蜂毒液蛋白具有抑制寄主血细胞免疫、调控寄主生长发育、抑制寄主生殖系统发育、调节寄主内分泌等功能,但一直以来对其组成成分知之甚少.近年来,不仅研究了寄生蜂毒液蛋白的生化特性,而且通过分离纯化、酶活测定、基因克隆等方法明确了寄生蜂毒液的部分蛋白组分.根据这些毒液蛋白性质和功能,可将其分为麻痹毒素、抗菌活性物质、酶类、酶的抑制剂等,它们在害虫生防、药理学和生理学研究中有着广阔的应用前景.该文作者就国内外对寄生蜂毒液蛋白组成成分的研究进展进行了综述,并对其应用前景进行了简要探讨. 相似文献
185.
Cytb、12SrRNA基因进化速度对构建系统进化树的影响 总被引:1,自引:0,他引:1
[目的]论证线粒体Cytb和12SrRNA基因不同进化速率影响构建的系统树拓扑结构。[方法]从GenBank下载了蛇亚目12科15种蛇线粒体全序列,提取Cytb和12SrRNA基因序列,选用GTR+I+G核苷酸替代模型,基于最大似然法,用PAUP4.0软件分别构建2个基因的系统关系树。[结果]在选用相同的软件、建树方法和研究物种的情况下,构建的系统树拓扑结构差异主要是因为线粒体Cytb和12SrRNA基因进化速率不同产生的。[结论]在分子系统进化研究中,要针对不同的研究物种和研究目的,选择合适的基因构建系统进化树。 相似文献
186.
187.
ZHANG Hui-zhong WANG Mei WEI Yi-ping CAO Yong-ke LI Hai-gang CHEN Ju YANG Yan-qi HUA Ping WU Cheng LIU Jin-geng 《园艺学报》2007,23(9):1716-1719
AIM: To investigate the expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and hepatocyte growth factor (HGF) in non-small-cell lung carcinoma (NSCLC) and their relationship with lymphoid metastasis and prognosis.METHODS: Expression of EMMPRIN and HGF in 77 cases of patients with NSCLC was detected immunohistochemically.The relationship of expression of EMMPRIN and HGF with tumor size,smoking,histological type,differentiation,lymphoid metastasis,clinical stage,and prognosis was analyzed.RESULTS: The expressive rates of EMMPRIN and HGF were 68% and 44%,respectively.The expressions of EMMPRIN and HGF were associated positively with lymphoid metastasis (r=0.371 and 0.339,P<0.01),and inversely with survival time (P<0.01).No relationship was found between the expression of EMMPRIN,HGF and smoking,tumor size,histological type and differentiation (P>0.05).The expression of EMMPRIN was associated with the expression of HGF in NSCLC.CONCLUSION: The expression of EMMPRIN and HGF is associated with lymphoid metastasis and prognosis in NSCLC.Overexpression of EMMPRIN and HGF implies infavourable prognosis in NSCLC. 相似文献
188.
AIM:To observe the expression and tissue localization of matrix metalloproteinase 9 (MMP-9) and transforming growth factor beta 1 (TGF-β1) in the rat acute cerebral ischemia model. METHODS:Male Wistar rats were used to establish acute cerebral ischemia model by a suturing method. The rats were divided into normal control group, sham group and ischemia 6 h, 12 h, 1 d, 2 d, 6 d and 14 d groups. The rat cerebral cortex and hippocampus of the brain were collected at different time points.The mRNA and protein levels of MMP-9 and TGF-β1 in the brain tissues were detected by real-time PCR and in situhistochemistry staining, respectively. The levels of MMP-9 and TGF-β1 in the plasma were also measured by ELISA. RESULTS:The results of real-time PCR showed that the mRNA levels of MMP-9 began to increase 6 h after acute ischemia and reached to a peak 2 d after acute ischemia. Similarly, the mRNA level of TGF-β1began to rise 12 h after acute ischemia and reached to the highest level 6 d after acute ischemia. Compared with the sham rats, the mRNA levels of MMP-9 and TGF-β1 in the rat brains that collected at ischemic time of 12 h, 1 d, 2 d, 6 d and 14 d were significantly increased. Moreover, results of in situhistochemical staining showed that the expression of MMP-9 was detected at cerebral cortex and hippocampus 1 d after acute cerebral ischemia.Further studies showed that MMP-9 dyeing of the rat cerebral cortex was most obvious 2 d after the acute cerebral ischemia. Similarly, the rat cortex and hippocampus began to express TGF-β1 2 d after acute ischemia and TGF-β1 staining at rat cerebral cortex was most obvious 6 d after the acute cerebral ischemia. In addition, ELISA showed that the increase in MMP-9 and TGF-β1 was detected in the plasma 12 h after ischemia. Compared with the sham rats, the level of these 2 factors significantly upregulated since 1 d after ischemia. CONCLUSION: The brain tissue itself contributes to the upregulation of MMP-9 and TGF-β1 post acute cerebral ischemia, which shed light on the related research in the field. 相似文献
189.
Kazuharu TAKEUCHI Satoshi KUBOTA Masato KINOSHITA Haruhiko TOYOHARA Morihiko SAKAGUCHI 《Fisheries Science》2002,68(3):610-617
ABSTRACT: We have cloned a cDNA encoding the MMP-9 from a carp epidermal cell (EPC) cDNA library. The clone contains a 2025-base pair (bp) open reading frame encoding a protein of 674 amino acids. The deduced amino acid sequence shares 68% and 69% identity with medaka and Japanese flounder MMP-9. The hinge domain of the carp MMP-9, like those of the other non-mammalian species, lacks a type V collagen-like region that is typical of mammalian MMP-9. Gelatin zymography and immunoblot analysis of conditioned media of EPC cells and cDNA-transfected COS-7 cells detected a 76-kDa gelatinase. The apparent molecular mass of the carp zymogen is much smaller than those of its mammalian counterparts while almost identical with that of chicken 75-kDa gelatinase B-like enzyme. Although hypo-osmotic stress induced the elevation of MMP-9 mRNA level in EPC cells, no significant change in the protein in conditioned medium was detected during hypo-osmotic stress. Northern blot analysis detected a large amount of MMP-9 mRNA in carp kidney and spleen, suggesting the high expression of MMP-9 in blood cells, neutrophils, and macrophages. The smaller amount of MMP-9 mRNA was detected in gill, heart, fin, and eye, whereas none of the mRNA was detected in the hepatopancreas, intestine, brain, muscle, and skin. 相似文献
190.
Masato KINOSHITA Taijiro YABE Mitsutoshi KUBOTA Kazuharu TAKEUCHI Satoshi KUBOTA Haruhiko TOYOHARA Morihiko SAKAGUCHI 《Fisheries Science》2002,68(3):618-626
SUMMARY: Toughness is one of the most important elements that define the commercial value of the raw meat of fish. Degradation of the extracellular matrix is thought to be a cause of postmortem tenderization of fish meat. A previous study has suggested that this tenderization is caused mainly by metalloproteinases. The present study seeks to identify the proteinase(s) involved in tenderization; hence, cloned cDNA of two gelatinases from Japanese flounder, which showed high homology with mammalian matrix metalloproteinase (MMP)-2 and MMP-9, were designated as jfMMP-2 and jfMMP-9 , respectively. Northern blot analysis revealed that jfMMP-2 mRNA was expressed almost ubiquitously in adult tissues including the brain, muscle, gill, heart, gut, kidney, spleen, testis, and ovary. In contrast, the expression of jfMMP-9 mRNA was observed in those tissues which were abundant in blood cells, such as kidney, spleen, heart, and gill. Both recombinant proteins (jfMMP-2 and jfMMP-9) produced with the COS-7 cell system exhibited gelatin-degrading activity that was sensitive to 1,10-phenanthroline, a typical metalloproteinase inhibitor. 相似文献