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81.
In this work, a set of pea accessions obtained from the Vavilov Research Institute (VIR) collection comprising 83 P. sativum samples, including representatives of three subspecies, was studied using the AFLP method. Local cultivars for different uses with maximum ecological and geographical diversity (including those from the centers of origin of the species) were predominantly chosen for the study; a number of their morphological and biological characteristics were evaluated. We obtained 382 polymorphic AFLP fragments; each sample was characterized by a unique set of fragments. The genetic diversity of the studied material was evaluated, and a wide range of genetic differences in the investigated samples (0.07–0.27) was demonstrated. The affiliation of the samples to the certain subspecies was not confirmed by the obtained data; the ecogeographical differentiation of the samples was not reflected by the data. Factor analysis allowed us to identify the sample groups of European and Asian origin and the intermediate nature of most of the samples from the studied set of pea accessions.  相似文献   
82.
Rhipicephalus sanguineus (Latreille) (Ixodida: Ixodidae) is a three‐host dog tick found worldwide that is able to complete its' entire lifecycle indoors. Options for the management of R. sanguineus are limited and its' control relies largely on only a few acaricidal active ingredients. Previous studies have confirmed permethrin resistance and fipronil tolerance in R. sanguineus populations, commonly conferred by metabolic detoxification or target site mutations. Herein, five strains of permethrin‐resistant and three strains of fipronil‐tolerant ticks were evaluated for metabolic resistance using synergists to block metabolic enzymes. Synergist studies were completed with triphenyl phosphate (TPP) for esterase inhibition, piperonyl butoxide (PBO) for cytochrome P450 inhibition, and diethyl maleate (DEM) for glutathione‐S‐transferase inhibition. Additionally, increased esterase activity was confirmed using gel electrophoresis. The most important metabolic detoxification mechanism in permethrin‐resistant ticks was increased esterase activity, followed by increased cytochrome P450 activity. The inhibition of metabolic enzymes did not have a marked impact on fipronil‐tolerant tick strains.  相似文献   
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The biotechnological method of synthesis of ribavirin, vidarabin, and 6-azauridine by the use of immobilized recombinant enzymatic preparations of nucleoside phosphorylase was improved. The effect of ribavirin and its combinations with the other synthesized nucleosides on the reproduction of Vaccinia virus was studied on the culture of Vero cells. The combination of ribavirin and vidarabin was shown to provide the antiviral effect at lesser concentrations than with these compounds taken separately.  相似文献   
85.
目的:探讨转化生长因子β2(TGF-β2)在低氧条件下诱导骨髓基质干细胞(BMSCs)向软骨细胞分化的作用。方法:无菌条件下分离Wistar大鼠股骨骨髓,采用全贴壁培养法纯化BMSCs。传6代后,将细胞随机分为3组,A组加入25 ng/mL TGF-β2在1%氧浓度条件下培养;B组加入25 ng/mL TGF-β2在21%氧浓度条件下培养;C组仅加入含10%胎牛血清的DMEM-α培养液在1%氧浓度条件下培养。3周后,通过甲苯胺蓝染色检测细胞糖胺多糖,聚合酶链反应检测Ⅱ型胶原和蛋白聚糖(Aggrecan)的表达水平。结果:骨髓细胞经换液后贴壁聚集生长,形态均一,连续传代后形态无明显改变。分组培养第1周,A、C组生长速度低于B组;第2周各组均出现不规则形态细胞,A、C组细胞形态小于B组;第3周各组均可见透明样基质,以A组最明显。3周后行甲苯胺蓝染色,A组细胞内外均可见丰富的蓝染颗粒,B、C组染色较A组略浅。A组Ⅱ型胶原的表达相对量(1.246±0.287)高于B组(0.973±0.365)、C组(0.802±0.196),差异有统计学意义(P〈0.05);B、C组比较无明显差异(P〉0.05)。A组Aggrecan的表达相对量(0.833±0.375)高于B组(0.724±0.173)、C组(0.602±0.091),差异有统计学意义(P〈0.05);B、C组比较无明显差异(P〉0.05)。结论:TGF-β2联合低氧环境可明显促进骨髓基质干细胞分化为软骨细胞。  相似文献   
86.
Serotonergic anorexigens are the primary pharmacologic risk factor associated with pulmonary arterial hypertension (PAH), and the resulting PAH is clinically indistinguishable from the heritable form of disease, associated with BMPR2 mutations. Both BMPR2 mutation and agonists to the serotonin receptor HTR2B have been shown to cause activation of SRC tyrosine kinase; conversely, antagonists to HTR2B inhibit SRC trafficking and downstream function. To test the hypothesis that a HTR2B antagonist can prevent BMRP2 mutation induced PAH by restricting aberrant SRC trafficking and downstream activity, we exposed BMPR2 mutant mice, which spontaneously develop PAH, to a HTR2B antagonist, SB204741, to block the SRC activation caused by BMPR2 mutation. SB204741 prevented the development of PAH in BMPR2 mutant mice, reduced recruitment of inflammatory cells to their lungs, and reduced muscularization of their blood vessels. By atomic force microscopy, we determined that BMPR2 mutant mice normally had a doubling of vessel stiffness, which was substantially normalized by HTR2B inhibition. SB204741 reduced SRC phosphorylation and downstream activity in BMPR2 mutant mice. Gene expression arrays indicate that the primary changes were in cytoskeletal and muscle contractility genes. These results were confirmed by gel contraction assays showing that HTR2B inhibition nearly normalizes the 400% increase in gel contraction normally seen in BMPR2 mutant smooth muscle cells. Heritable PAH results from increased SRC activation, cellular contraction, and vascular resistance, but antagonism of HTR2B prevents SRC phosphorylation, downstream activity, and PAH in BMPR2 mutant mice.  相似文献   
87.
Polymorphism of microsatellite loci of the nuclear genome was examined in 29 cultivars and accessions of wild potato (S. tuberosum, S. stoloniferum, S. demissum, and S. phureja). Nine SSR markers, most informative (PIC = 0.61–0.92) for genotyping of the cultivars of Russian breeding were selected. Polymorphism of the selected SSR loci was characterized, and prevailing, as well as unique SSR allele phenotypes were described. A total of 87 allele phenotypes were identified. The highest number of allele phenotypes was detected for the SSR1 (17), ST83/84 (12), and STRBCS1b (12) loci. The least numbers of allele phenotypes were typical of the ST47/48 (5) and STWIN12G (6) loci. Based on the microsatellite loci analyzed, for each of the cultivars examined, its allele formula was established. The latter can be uses as the cultivar molecular genetic passport. Diagnostic sets of most informative loci (SSR markers), enabling identification of the genotypes of all potato cultivars of Russian breeding examined, were determined  相似文献   
88.
89.
韩伟  刘杨  齐蕾  单丽辉  柴翠翠  王立峰 《生物磁学》2011,(19):3767-3770
目的:探讨胃癌组织中Tenascin蛋白、微血管密度(microvascular density,MVD)、Ki-67的表达及其与临床病理特征的关系。方法:采用免疫组化Elivision法检测70例胃癌组织和20例癌旁正常组织中Tenascin、CD34和Ki-67的表达。结果:①正常胃黏膜上皮Tenascin阴性,胃癌中的Tenascin主要表达于肿瘤相关纤维母细胞的胞质中,且与胃癌的Lauren分型、分化程度、临床分期、淋巴结转移显著相关(P〈0.05);②胃癌中MVD和Ki-67-LI(标记指数)均高于正常胃黏膜(P〈0.001),且均与胃癌的临床分期、浸润深度、淋巴结转移显著相关(P〈0.05);结论:胃癌组织中Tenascin可抑制胃癌的演进,MVD及Ki-67可作为胃癌患者预后的预测指标,联合检测胃癌组织Tenascin、MVD、Ki-67的表达情况,对于进一步了解胃癌的生物学行为和判断预后具有一定的临床价值与意义。  相似文献   
90.
The synthesis of globin proteins in blood reticulocytes of homozygous beta-thalassemic patients from Tadzhikistan has been previously studied. beta-thalassemia with sharp repression of beta-globin protein synthesis (alpha/beta greater than 10) has been shown to be most representative for the region. In this work, the synthesis of globin proteins has been studied in bone marrow cells of homozygous beta-thalassemic patients. Comparison of data on globin synthesis in bone marrow cells and in blood reticulocytes of the patients has revealed that in some cases the disbalance of chain synthesis in both cell types is equal. In other cases the disbalance in bone marrow cells is less than in blood cells, indicating the instability of beta-globin mRNA that is partially degrading in the process of cell maturation. Homozygous beta-thalassemic cases with low content of Hb F in blood cells (5-10%), with substantial disbalance of alpha and beta-globin synthesis and marked production of gamma-globins in bone marrow cells and in blood reticulocytes are of special interest. It has been assumed that parallel to beta-thalassemia some instability of gamma-globin proteins takes place in these patients.  相似文献   
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