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排序方式: 共有530条查询结果,搜索用时 15 毫秒
1.
Body weight, testicle size and peripheral testosterone concentrations were measured in 35 water buffalo bulls at 5, 15, 17, 21, 25 and 38 months of age. These parameters were studied in all animals during the same month (October), so the changes due to age were independent of changes in photoperiod and temperature. Body weight increased linearly with age. The testicular size measured in terms of scrotal circumference as related to age, showed a curvilinear increase; the average rate of testicular growth was maximum between 15 and 25 months. Plasma testosterone levels were low between 5 and 21 months. A significant rise in plasma concentration of testosterone was observed at 25 months reaching peak levels at 38 months. The mean age of sexually mature bulls at the time of first ejaculation of semen with motile sperm, was 24.9±0.9 months (n=9). It has been concluded that in the Nili-Ravi buffalo bulls the sexually quiescent period (prepubertal) extends up to 15 months of age and sexual maturation as indicated by the presence of motile sperm in the ejaculate is attained at about 25 months. 相似文献
2.
Stable coronary artery disease (CAD) can cause repetitive reversible myocardial ischaemia, and it seems to be possible that reversibly injured myocardium releases small amounts of soluble cytoplasmic proteins. Hence, the aim was to evaluate the effect of stable CAD on baseline serum levels of cardiac biomarkers. We studied 68 consecutive outpatients referred for gated myocardial perfusion imaging. Before a treadmill exercise test, blood samples for measurement of creatine kinase (CK), CK-myocardial band (CK-MB) mass, myoglobin, aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were collected. Normal perfusion patterns were detected in 29 (43%) patients (group 1) and perfusion defects were detected in 39 (57%) patients (group 2). Baseline serum levels of biomarkers except CK were significantly higher in group 2 (p=0.001). Stable CAD increases baseline levels of CK-MB mass, myoglobin, AST and LDH in the serum and this increase is related to the extent and severity of the perfusion defect and to some extent the ejection fraction of the left ventricle. 相似文献
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Arslan A Kiralp S Toppare L Yagci Y 《International journal of biological macromolecules》2005,35(3-4):163-167
Immobilization of tyrosinase in conducting copolymer matrices of pyrrole functionalized polydimethylsiloxane/polypyrrole (PDMS/PPy) was achieved by electrochemical polymerization. The polysiloxane/polypyrrole/tyrosinase electrode was constructed by the entrapment of enzyme in conducting matrices during electrochemical copolymerization. Maximum reaction rate (V(max)) and Michaelis-Menten constant (K(m)) were investigated for immobilized enzyme. Enzyme electrodes were prepared in two different electrolyte/solvent systems. The effect of supporting electrolytes, p-toluene sulfonic acid and sodium dodecyl sulfate on the enzyme activity and film morphology were determined. Temperature and pH optimization, operational stability and shelf-life of enzyme electrodes were also examined. Phenolic contents of green and black tea were determined by using enzyme electrodes. 相似文献
5.
Raquel Xavier António M. Santos D. J. Harris Murat Sezgin Margarida Machado Madalena Branco 《Zoologica scripta》2012,41(4):386-399
Xavier, R., Santos, A. M., Harris, D. J., Sezgin, M., Machado, M., Branco, M. (2012). Phylogenetic analysis of the north‐east Atlantic and Mediterranean species of the genus Stenosoma (Isopoda, Valvifera, Idoteidae). —Zoologica Scripta, 41, 386–399. The marine isopod genus Stenosoma is widespread in the northern hemisphere. However, 12 of its 14 known species are found within the Mediterranean basin and adjacent regions of the north‐east Atlantic and the Black Sea. Such a high level of diversity confined to a limited region of a much larger circumglobal distribution suggests that the Mediterranean region may have played a crucial role in the evolutionary history of this genus. In the present work, the phylogeny of the genus Stenosoma was investigated on the basis of DNA sequencing data from one nuclear (28SrRNA) and two mitochondrial (COI, ND4) gene fragments obtained for nine of 12 Atlantic–Mediterranean species. Divergence time estimates point to a Tethyan origin of Stenosoma and suggest that the speciation events from which stem most of the extant species took place well before the Messinian Salinity Crisis. Stenosoma spinosum and Stenosoma appendiculatum are the only exceptions, as they apparently arose within the Mediterranean during the Pleistocene. Phylogenetic reconstruction agrees with current taxonomic status of most species. However, Stenosoma capito clustered in two distinct and well‐supported clades, one composed of eastern Mediterranean and Black Sea specimens and the other by western Mediterranean and Atlantic ones. Such polyphyly suggests the existence of a previously unrecognized species, Stenosoma sp., which so far has been confounded with S. capito. 相似文献
6.
Miodownik Saul; Melendez Jose; Carlon Vittoria Arslan; Burda Brian 《Journal of applied physiology》1998,84(6):2177-2182
Themethanol-burning lung model has been used as a technique for generatinga predictable ratio of carbon dioxide production (CO2) to oxygen consumption(O2) or respiratoryquotient (RQ). Although an accurate RQ can be generated, quantitativelypredictable and adjustableO2 andCO2 cannot be generated. Wedescribe a new burner device in which the combustion rate of methanolis always equal to the infusion rate of fuel over an extended range ofO2 concentrations. This permitsthe assembly of a methanol-burning lung model that is usable withO2 concentrations up to 100% and provides continuously adjustable and quantitativeO2 (69-1,525 ml/min)and CO2 (46-1,016ml/min) at a RQ of 0.667. 相似文献
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Zainab Saad Yusuf Tugba Kevser Uysal Ender Simsek Alessio Nocentini Sameh Mohamed Osman Claudiu T. Supuran
zen
zensoy Güler 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1340
Carbonic anhydrases (EC 4.2.1.1) catalyse the reversible hydration of CO2 into bicarbonate and protons. As a hypoxia-sensitive and tumour-associated isoform, isoform CA IX, is significantly overexpressed in various malignancies, being a validated target for new anticancer/antimetastatic drugs. A multitude of studies has shown that CA IX inhibition decreases cancer cell proliferation and metastasis through pHe/pHi modulation and enhancement of ferroptosis among others. Numerous studies demonstrated increased efficacy of cytotoxic drugs combined with CA inhibitors (CAIs) in various cancer types. We tested the inhibitory effect of boric acid (BA), an inorganic Lewis acid, on CA IX as well as other isoforms (CA I, II, and XII). BA acted as a millimolar in vitro CAI, decreased proliferation of two cancer cell lines, although not strong correlations between the in vitro inhibition and in vivo effects were observed. The mechanism of antiproliferative action of BA should be investigated in more detail. 相似文献
9.
CaGE: cardiac gene expression knowledgebase 总被引:4,自引:0,他引:4
Bober M Wiehe K Yung C Onal Suzek T Lin M Baumgartner W Winslow R 《Bioinformatics (Oxford, England)》2002,18(7):1013-1014
CaGE is a Cardiac Gene Expression knowledgebase we have developed to facilitate the analysis of genes important to human cardiac function. CaGE integrates the functionality of the LocusLink database with data from several human cardiac expression libraries, phenotypic data from OMIM and data from large-scale microarray gene expression studies to create a knowledgebase of gene expression in human cardiac tissue. The knowledgebase is fully searchable via the web using several intuitive query interfaces. Results can be displayed in several concise easy to navigate formats. AVAILABILITY: CaGE is located at http://www.cage.wbmei.jhu.edu 相似文献
10.
Tufekci Kemal Ugur Alural Begum Tarakcioglu Emre San Tugba Genc Sermin 《Molecular biology reports》2021,48(5):4171-4180
Molecular Biology Reports - Neuronal senescence, triggered by telomere shortening, oncogene activation, DNA damage, or oxidative stress, has been associated with neurodegenerative diseases’... 相似文献