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201.
INTRODUCTIONMa1n11la1iaIlskeletal1llusclefibresare(listiIlgl1ishedint()severaltypesacc()rdillgtodifferentclassificatiollscl1e111es.Eachtypeofmusc1efibresl1asasetofspecificcharacteristics.Ollewell-kllowl1waytoclassifymusclefibresistodividethemintotwobroadtypestslow-twitcI1ortypeIfibres,andfast-twitchortypelIfibres.ThefOrmerllormallyappearsreda11dthelaterappearswhite.Theypossesswidedifferellceswithrespectt()physiol()gical,biochemical,andmorpho1ogica1pl1ellotypiccharacteristics,suchasisom…  相似文献   
202.
邯郸地区155000人群的遗传流行病学调查任新鸾(河北省邯郸医学高等专科学校,邯郸056029)赵美英吕丽英张风梅赵丽萍(河北省邯郸县妇幼保健站,邯郸056000)TheEpidemiologySurveyofInheritanceDiseaseof...  相似文献   
203.
一种优化的植物组织RNA原位杂交技术   总被引:8,自引:1,他引:7  
一种优化的植物组织RNA原位杂交技术①陈绍荣毕学知吕应堂杨弘远(武汉大学生命科学学院,武汉430072)AOptimizedinSituRNAHybridizationTechniqueinPlantTisuesCHENShaorongBIXuezh...  相似文献   
204.
暗纹东方TUN 同工酶生化表现型的研究   总被引:7,自引:0,他引:7  
利用聚丙烯酰胺凝胶垂直平板电泳方法,对暗纹东方|TUN|的心、肝、肾、肌、性腺5种不同组织的7种同工酶(EST、LDH、POD、MDH、SOD、SDH、α-AMY)进行了研究, 讨论了各同工酶的基因表达谱式,观察到EST同工酶存在着多态现象;LDH同工酶有二个基因位点,但只表现3条带,A与B亚基的结合受阻; MDH同工酶存在性别差异,说明决定MDH同工酶表达的因素在不同性别中存在差异;SOD同工酶有3个基因位点。各同工酶酶谱稳定,有组织特异性,但EST、MDH、SOD、POD同工酶在各组织器官中又表现出较大的一致性,有利于物种的鉴定。α-AMY与SDH只在个别组织中有活性,可能与特定组织与器官的形态发生与机能分化有关。 Abstract:By means of polyacrylamid gel electrophoresis seven isozymes(EST.LDH,SOD,MDH,SDH, α-AMY)in heart,liver,kidney,muscle and gonad of Fugu obscurus were studied.The gene expression patterns of each isozyme were analyzed.The results indicated that polymorphism was detected in EST isozymes;LDH isozymes had two loci,but only three bands could be observed,the random association of two subunits(A and B)were restricted;Some MDH isozymes existed sexual differences in identical tissues.The suggested that the factors controlling the expression of MDH isozymes were different between sexes.All the isozyme phenotypes exhibited tissue-specificity and stability,but EST,MDH,SOD and POD isozymes showed relatively consistence in the five tissues.Their characteristic bands could be used in species determination.The activities of SDH andα-AMY isozymes could only be detected in some tissues and closely correlated to the morphological or functional differentiation of those tissues or organs.  相似文献   
205.
海岛棉无腺体突变基因Gl E 2 的遗传研究   总被引:1,自引:0,他引:1  
本文对海岛棉无腺体突变基因Gl e 2 的遗传行为进行了研究。结果表明,Gl e 2是一个完全显性基因,不是Kohel等(1984)认为的部分显性基因。基因Gl2和Gl3存在着剂量效应。不稳定的遗传背景也会影响Gl e 2与Gl2和Gl3的相互作用。Gl1及等位基因gl1与Gl e 2没有相互联系。  相似文献   
206.
小鼠脊髓重与颈膨大截面积QTL研究   总被引:2,自引:0,他引:2  
应用近交系小鼠A/J和C5 7BL/ 6J以及其F2 代重组小鼠定位脊髓重与颈膨大截面积数量性状基因座(QuantitativeTraitLoci,QTL)。结果表明 13个QTL与脊髓重和截面积相关 ,这些QTL分别位于 2、4、8、14、15、17、18、19和X染色体上。其中 6个QTL与脊髓重相关 ;4个QTL与颈膨大截面积相关 ;3个QTL与二者均相关。在 13个QTL中 ,3个QTL (P <0 0 1)———SC1(位于D15Mit15 8附近 )、SC2 (DXMit14 0附近 )和SC3(DXMit6 4附近 )其表型变异的解释率分别为 2 4 %、19%和 15 % ;加性效应分别为 - 3 78、3 4 1和 2 0 6mg。其他QTL的P值在 0 0 1~ 0 0 5之间。在上述 3个QTL中 ,SC1是唯一与脊髓重和面积均相关的QTL  相似文献   
207.
The endogenous retrovirus (ERV) is one kind ofretroviruses that integrated in the genome in the formof provirus and replicates with the proliferation of hostcells. The ERV may play a significant role in the evo-lution, pathology and physiology of animals[1]. Now,proviral sequences of ERV have been found in the ge-nome of many vertebrates, and the release of virionshas also been detected both in vivo and in vitro. Porcine endogenous retrovirus (PERV) embeddedin the genome of pigs belo…  相似文献   
208.
The review on problem tapetoretinal degeneration (TD) which represents serious enough and incurable disease revealed with frequency 1 : 3500-5000 in general population is presented. The most often reason of occurrence TD are mutations in RHO, RDS and RPE65 genes. The precise interrelation of pigmentary degenerations of a retina and mutations in genes RHO, RDS and RPE65 will allow to develop approaches of DNA--diagnostics of hereditary dystrophies of a retina so frequently meeting in clinical practice of the ordinary ophthalmologist, and also to pass at medical genetics consultation from probability estimations of risk of disease to unequivocal. Also the molecular analysis of genes changes in the providing correct functioning of photoreceptors and pigmentary epithelium of a retina and determining pathological changes at TD, will allow to approach to understanding of the physiological and pathological processes proceeding in a retina and by that will serve becoming and development pathogenic to caused therapy TD closer.  相似文献   
209.
Medium polarity fractions of the hexane extracts of the stems of Bursera suntui afforded six previously known (1-6) and four hitherto unknown verticillane derivatives: (1S,3Z,7S,8S,11S,12S)-(+)-7,8-epoxyverticill-3-en-12,20-diol (7), (1S,3Z,7S,8S,11S,12S)-(+)-7,8-epoxyverticill-3-en-12,20-diol 20-acetate (8), (1S,3Z,7S,11S,12S)-(+)-verticilla-3,8(19)-dien-7,12,20-triol (9), and (1S,3Z,7S,11S,12S)-(+)-verticilla-3,8(19)-dien-7,12,20-triol 20-acetate (10). Acetylation of 9 and 10 yielded (1S,3Z,7S,11S,12S)-(+)-verticilla-3,8(19)-dien-7,12,20-triol 7,20-diacetate (11), while hydrolysis of 8 gave 7. The structures and stereochemistry of 7-11 were established by spectroscopic analyses, particularly by 1D and 2D NMR spectra and HRESIMS. The conformational preferences of 7-11 were studied by molecular mechanics modelling employing the Monte Carlo protocol followed by B3LYP/DGDZVP DFT calculation, thus supporting the observed 1H NMR NOESY cross peaks.  相似文献   
210.
Previously we have shown that MCF-7 human breast tumor growth is stimulated after prolonged treatment with dietary soy protein isolate (SPI). However, the effects are attenuated when SPI is combined with flaxseed (FS). This study determined the changes that occur in tumor growth biomarkers, after both short- and long-term treatment with SPI, FS or their combination, to help identify signaling pathways potentially involved in SPI-stimulated tumor growth. Ovariectomized mice with established MCF-7 tumors were fed basal diet (control), 20%SPI, 10%FS, or SPI+FS for 2 or 25 weeks. After 2 weeks, there were no differences in tumor size, however, compared with control, SPI-treated tumors had higher IGF-IR and cyclin D1 while FS and SPI+FS-fed mice had lower pMAPK expression. After 25 weeks, SPI-treated tumors were larger, had higher proliferation, ERalpha, cyclin D1, IGF-IR, and pMAPK and lower ERbeta and HER2 levels. When combined with FS, however, the effects on these tumor biomarkers induced by SPI were attenuated. This study demonstrates that SPI and FS differently modulate tumor biomarkers of estrogen and growth factor signaling pathways, after both short- and long-term treatment, which may indicate a role of these pathways in the tumor stimulatory effects of SPI and the tumor inhibitory effects of FS.  相似文献   
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