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101.
不同来源的供体细胞对水牛体细胞核移植效果的影响   总被引:1,自引:0,他引:1  
采用电融合方法,探讨不同来源的供体细胞对水牛核移植效果的影响。体外成熟培养22~24h的水牛卵母细胞,在含有5μg/mL细胞松弛素B的操作液中进行去核,然后将经0.1μg/mLAphidicolin(APD)+0.5%FBS培养2~9d的水牛不同来源的供体细胞,注射到去核的卵母细胞卵周隙中,电融合形成重构胚。重构胚经5μmol/L离子霉素激活处理5min,并在2mmol/L的6-DMAP中培养3h后,在含有颗粒细胞单层细胞的微滴中培养7~9d,观察其卵裂和胚胎发育情况。结果发现,来自水牛胎儿耳部或腹部组织块的成纤维细胞用作供体细胞,其重组胚的融合率及体外发育能力差异不显著(P>0.05),且细胞培养方法(组织块法或酶消化法)对其核移植效果没有影响;来自编号011010的胎儿耳皮成纤维细胞重组胚的囊胚发育率显著高于来自编号030323和030410细胞(31.45%vs10.96%和14.49%,P<0.05),但它们的融合率、卵裂率无显著差异(P>0.05)。以上结果表明:经不同培养方法培养的细胞或来自身体不同部位的组织的成纤维细胞均可作为核移植研究的供体细胞,但是水牛体细胞核移植效果受供体的个体差异的影响。  相似文献   
102.
采用超薄切片和透射电子显微镜技术对鸭病毒性肠炎病毒CH强毒株(DEV-CHv)在鸭胚成纤维细胞(DEF)中的形态发生学进行了研究。结果表明,DEV-CHv吸附到DEF细胞上以后通过囊膜和细胞膜间发生融合的方式侵入宿主细胞;病毒在细胞核内完成病毒核酸的生成、核酸与衣壳的装配;病毒核衣壳通过核膜-内质网膜系统从细胞核转运到内质网池中并在内质网池中得到皮层结构;获得了皮层的DEV-CHv核衣壳通过出芽方式释放到细胞空泡内得到囊膜结构后成为成熟病毒;细胞空泡内的成熟DEV-CHv可通过细胞的胞吐作用被释放到细胞外,或在空泡破裂时被释放到细胞外。  相似文献   
103.
AIM:To investigate the effect of lentivirus-mediated DKK3 overexpression on the apoptosis of hypertrophic scar fibroblasts. METHODS:Human hypertrophic scar fibroblasts were isolated and cultured in vitro. The cells were divided into control group, vector (negative control lentivirus infection) group and DKK3 (pcDNA3.1-DKK3 lentivirus infection) group. The overexpression effect was determined by RT-qPCR and Western blot. The cell viability was measured by MTT assay. The apoptosis was analyzed by flow cytometry. The protein levels of cleaved caspase-9, collagen type Ⅱ (COL Ⅱ), COL I and cleaved caspase-3 in the cells, and cytochrome C in the cytoplasm and mitochondrion were detected by Western blot. RESULTS:After transfection with pcDNA3.1-DKK3, the expression of DKK3 at mRNA and protein levels was increased in the hypertrophic scar fibroblasts (P<0.05). The viability of hypertrophic scar fibroblasts in DKK3 group was decreased, and the apoptotic rate was increased. The protein levels of cleaved caspase-9 and cleaved caspase-3 were increased in the cells, and the protein levels of COL Ⅱ and COL I were decreased. The protein level of cytochrome C was increased in the cytoplasm, while the protein level of cytochrome C in the mitochondrion decreased. Compared with vector group, these differences were statistically significant (P<0.05). CONCLUSION:Lentivirus-mediated DKK3 overexpression induces apoptosis and reduces collagen synthesis in the fibroblasts from hypertrophic scars.  相似文献   
104.
以‘嘎拉’苹果(Malus × domestica Borkh.)为试材,克隆了乙烯响应因子基因MdERF11(序列号 MDP0000756341)。测序发现,该基因包含全长为483 bp的完整开放阅读框,编码161个氨基酸。系统进化树分析表明,这一乙烯响应因子与拟南芥AtERF11蛋白同源序列相似性最高。利用PlantCare数据库进行基因启动子顺式作用元件预测,MdERF11启动子序列中含有与脱落酸(ABA)、乙烯及干旱信号相关的顺式作用元件。荧光定量PCR分析表明,MdERF11在苹果的各组织中均有表达,在叶柄和果实中表达量相对较高;并且MdERF11的表达明显受到ABA的诱导。在外源ABA的处理下,MdERF11过量表达的苹果愈伤组织的生长势明显比野生型强,表明MdERF11降低了苹果愈伤组织对ABA的敏感性。  相似文献   
105.
目的:探讨长春新碱对天祝白牦牛胚胎成纤维细胞生长的抑制作用,并用碱性磷酸酶指标判断天祝白牦牛胚胎成纤维细胞在长春新碱作用下去分化的可能性。方法:选取白牦牛胚胎成纤维细胞生长良好的24孔培养板,分别滴加浓度依次为0.1、0.5、1.0、1.5、2.0、2.5μg/mL长春新碱,每天在倒置相差显微镜下观察不同浓度的长春新碱对细胞形态的作用,并进行碱性磷酸酶染色检测。结果:适量浓度的长春新碱可以使细胞的形态发生变化(细胞变圆),而且在去除长春新碱后,细胞能正常生长。高浓度的长春新碱会使细胞死亡崩解。长春新碱并不能使白牦牛胚胎成纤维细胞中的碱性磷酸酶浓度增高。结论:长春新碱浓度为0.5μg/mL时,对白牦牛胚胎成纤维细胞的抑制作用最佳,但是它并不能使细胞中碱性磷酸酶的含量增高。  相似文献   
106.
以东北野猪成纤维细胞为研究对象,利用实时荧光定量PCR技术,分析4、15、25和32℃不同温度冷应激条件下细胞内HSPT0mRNA表达变化规律。结果显示在冷应激的低温处理过程中,HSP70mRNA转录量在各温度均为见显著增加;在冷应激的复温培养过程中,HSP70mRNA转录量在4℃和15℃处理后4h后,复温培养的4~8h显著增加(P〈O.05);在25℃和32℃处理后4h后,复温培养未能诱导细胞内HSP70mRNA转录量显著增加(P〉0.05);细胞在4℃和15℃处理2、4、6和8h后,复温培养4h,HSP70mRNA转录量随处理温度的减低和时间的延长而增加,处理4~8h组显著高于对照组(P〈0.05),在25℃和32℃处理2、4、6和8h后,复温培养未能显著诱导HSP70mRNA的转录(P〉0.05)。结果表明,冷应激诱导东北野猪成纤维细胞内HSP70mRNA转录量的增加,不是发生在低温处理的应激阶段,而是发生在复温后的细胞应激阶段,温和冷应激(25~32℃)未能诱导复温后HSP70mRNA转录量的显著增加,强度冷应激(4~15℃)诱导复温后HSP70mRNA转录量的显著增加,且与冷应激的强度和时间成正比。  相似文献   
107.
AIM:To investigate the effects of interferon-inducible protein 16 (IFI16) on the proliferation and migration of human brain vascular adventitial fibroblasts (HBVAFs). METHODS:The siRNA of IFI16 gene was transfected into HBVAFs. Forty-eight hours after transfection, the cells were exposed to 2×106 U/L interferon alpha (IFN-α) for 24 h. Cell cycle was analyzed by flow cytometry. Cell migration was determined by scratch assay and transwell method. The mRNA and protein levels of IFI16, p53 and p21 were measured by real-time PCR and Western blotting, respectively. RESULTS:After transfection with IFI16 siRNA, the expression of IFI16, p53 and p21 at mRNA and protein levels was decreased in HBVAFs, and the cell cycle at G1/S transition was promoted. Meanwhile, stimulated with IFN-α up-regulated the expression of IFI16, p53 and p21 at mRNA and protein levels, and inhibited the cell cycle transition at G1/S and cell migration in HBVAFs. Such effect was restrained by transfection with IFI16 siRNA into HBVAFs. CONCLUSION:The expression of IFI16 inhibits the proliferation and migration of HBVAFs, which may be related to the activation of p53 and p21 expression.  相似文献   
108.
研究不同培养体系对胎牛成纤维细胞体外培养的影响及用牛血清白蛋白代替血清培养胎牛成纤维细胞的可行性。利用M199、DMEM、α-MEM、DMEM/F124种培养体系通过组织块贴壁培养对成纤维细胞体外培养液进行筛选,以α-MEM组细胞生长状况较好。分别用含2、4、6、8、10mg/mL BSA的α-MEM培养液对胎牛成纤维细胞进行原代及传代培养,5种浓度的BSA对原代培养时细胞开始游离出组织块的时间影响不明显,均在培养后的48h有成纤维细胞和上皮细胞混合游离出,但在传代培养时,胎牛成纤维细胞在8mg/mL BSA浓度的α-MEM中贴壁率较高。结果表明:培养胎牛成纤维细胞时,可用BSA代替血清,较适宜的培养体系为含8mg/mL BSA的α-MEM培养液。  相似文献   
109.
AIM: To investigate the role of Rho-kinase signal pathway in rat cardiac fibroblasts (CFBs) proliferation and collagen synthesis induced by angiotensinⅡ (AngⅡ). METHODS: CFBs of neonatal Sprague-Dawley (SD) rats were isolated with the method of trypsin digestion and differential anchoring velocity. The CFBs were stimulated with AngⅡto induce fibrosis. Proliferation of CFBs was observed by MTT coloricmetric assay. Synthesis of collagen was detected by the hydroxyproline. The expression of Rho-kinase mRNA was examined using RT-PCR analysis. The extent of phosphorylation of myosin-binding subunit (MBS-P) of myosin phosphatase was quantified by Western blotting analysis, which was used to evaluate the activity of Rho-kinase.RESULTS: (1) Stimulation of neonatal SD rat CFBs with AngⅡ (10-7 mol/L) significantly increased CFBs proliferation and collagen synthesis (P<0.01). (2)Stimulation of neonatal SD rat CFBs with AngⅡ (10-7 mol/L) significantly increased the expression of Rho-kinase mRNA and rapidly activated Rho-kinase in a time-dependent manner. (3) Within a concentration coverage, hydroxyfasudil (H4413), a Rho-kinase inhibitor, effectively inhibited AngⅡ-induced CFBs proliferation and collagen synthesis (P<0.05 or P<0.01).CONCLUSION: Rho-kinase signal pathway may be one of the most important signal transducter for AngⅡ-induced CFBs proliferation and collagen synthesis in neonatal SD rats.  相似文献   
110.
小鼠胎儿成纤维细胞饲养层制备的研究   总被引:2,自引:0,他引:2  
研究主要探讨在制备小鼠胎儿成纤雏饲养层中,不同处理条件对小鼠胎儿成纤雏细胞分裂与存活的影响。结果表明:小鼠胎儿成纤雏细胞用适当处理浓度的丝裂霉素-C或适当强度的γ-射线处理一定的时间(10μg/mL 1-4h,20μg/mL 1—2.5h或21Gy和28Gy各处理1h),能有效地抑制其分裂,且不影响其活力。  相似文献   
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