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In this study, the preliminary analyses were conducted of enzymatic activities of uridine phosphorylase (UP) and thymidine phosphorylase (TP) in normal tissues and cancer tissues of the uterine cervix. The study was performed on 27 patients of cervical cancer, treated first in our hospital. Normal cervical tissues obtained from 15 patients undergoing hysterectomy for benign diseases were used as controls. The supernatant of the homogenated cervical tissues and the stroma (5-FU and ribose-1-P or deoxyribose-1-P) were analyzed by high performance liquid chromatography, and then the UP and TP activities calculated. TP activity was significantly greater than UP activity (P < 0.0001). Both UP and TP showed significantly greater activity in cancer tissues than in normal tissues (P < 0.0001). In the TP activity of the cancer tissues, there was no significant difference among the histological types, while the TP activity tended to be significantly higher in the cases with lymph node metastasis. These results showed that the TP-mediated route seemed important as the 5FU metabolic pathway in the uterine cervical tissues, and TP enzymatic activity might be associated with lymph node metastasis.  相似文献   
93.
When the homozygous active form of porcine TGF-β1 transgene (Tgf/Tgf) (under control of the rat glucagon promoter) is introduced into the nonobese diabetic mouse (NOD) genetic background, the mice develop endocrine and exocrine pancreatic hypoplasia, low serum insulin concentrations, and impaired glucose tolerance. To identify genetic modifiers of the diabetic phenotypes, we crossed hemizygous NOD-Tgf with DBA/2J mice (D2) or C3H/HeJ mice (C3H) and used the “transgenic mice” for quantitative trait loci (QTL) analysis. Genome-wide scans of F2-D Tgf/Tgf (D2 × NOD) and F2-C Tgf/Tgf (C3H × NOD), homozygous for the TGF-β1 transgene, identified six statistically significant modifier QTLs: one QTL (Tdn1) in F2-D Tgf/Tgf, and five QTLs (Tcn1 to Tcn5) in F2-C Tgf/Tgf. Tdn1 (Chr 13, LOD = 4.39), and Tcn3 (Chr 2, LOD = 4.94) showed linkage to body weight at 8 weeks of age. Tcn2 (Chr 7, LOD = 4.38) and Tcn4 (Chr 14, LOD = 3.99 and 3.78) showed linkage to blood glucose (BG) concentrations in ipGTT at 30, 0, and 120 min, respectively. Tcn1 (Chr 1, LOD = 4.41) and Tcn5 (Chr 18, LOD = 4.99) showed linkage to serum insulin concentrations in ipGTT at 30 min. Tcn2 includes the candidate gene, uncoupling protein 2 (Ucp2), and shows linkage to Ucp2 mRNA levels in the soleus muscle (LOD = 4.90). Identification of six QTLs for diabetes-related traits in F2-D Tgf/Tgf and F2-C Tgf/Tgf raises the possibility of identifying candidate susceptibility genes and new targets for drug development for human type 2 diabetes. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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1,2-Didocosahexaenoyl phosphatidylcholine (PC), which has highly unsaturated fatty acid at both sn-1 and sn-2 positions of glycerol, is a characteristic molecular species of bonito muscle. To examine the involvement of a de novo route in its synthesis, the molecular species of phosphatidic acid (PA) were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using a 1,3-bis[bis(pyridin-2-ylmethyl)amino]propan-2-olato dizinc(II) complex, a novel phosphate-capture molecule. However, 1,2-didocosahexaenoyl species could not be detected. Next, 1,2-didocosahexaenoyl PC synthesis by the cytosolic lysophosphatidylcholine (LPC)/transacylase was examined using endogenous LPC from bonito muscle, in which the 2-docosahexaenoyl species is abundant. The LPC/transacylase synthesized 1,2-didocosahexaenoyl PC as the most abundant molecular species. For further characterization, the LPC/transacylase was purified to homogeneity from the 100,000 x g supernatant of bonito muscle. The isolated LPC/transacylase is a labile glycoprotein with molecular mass of 52 kDa including a 5-kDa sugar moiety. The LPC/transacylase showed a PC synthesis (transacylase activity) below and above the critical micelle concentration of substrate LPC, and fatty acid release (lysophospholipase activity) was always smaller than the transacylase activity, even with a monomeric substrate. These results suggest that the LPC/transacylase is responsible for the synthesis of 1,2-didocosahexaenoyl PC.  相似文献   
95.
Polyoxins D, E, and F which possess 5-carboxyuracil as the nucleobase were reacted selectively with sodium bisulfite at pH 4.0 resulting in facile decarboxylation to afford corresponding 5,6-dihydrouracil-6-sulfonates and uracil type polyoxins (polyoxins L, M, and K) in good yield. The former compounds were also converted to the latter almost quantitatively with mild alkali treatment. Biological activities of the transformed compounds were described.  相似文献   
96.
Among the many tissue stem or progenitor cells recently being unveiled, endothelial progenitor cells (EPCs) have attracted particular attention, not only because of their cardinal role in vascular biology and embryology but also because of their potential use in the therapeutic development of a variety of postnatal diseases, including cardiovascular and peripheral vascular disorders and cancer. The aim of this study is to provide some basic and comprehensive information on gene expression of EPCs to characterize the cells in molecular terms. Here, we focus on EPCs derived from CD34-positive mononuclear cells of human umbilical cord blood. The EPCs were purified and expanded in culture and analyzed by a high-density oligonucleotide microarray and real-time RT-PCR analysis. We identified 169 up-regulated and 107 down-regulated genes in the EPCs compared with three differentiated endothelial cells of human umbilical vein endothelial cells (HUVEC), human lung microvascular endothelial cells (LMEC) and human aortic endothelial cells (AoEC). It is expected that the obtained list include key genes which are critical for EPC function and survival and thus potential targets of EPC recognition in vivo and therapeutic modulation of vasculogenesis in cancer as well as other diseases, in which de novo vasculogenesis plays a crucial role. For instance, the list includes Syk and galectin-3, which encode protein tyrosine kinase and β-galactoside-binding protein, respectively, and are expressed higher in EPCs than the three control endothelial cells. In situ hybridization showed that the genes were expressed in isolated cells in the fetal liver at E11.5 and E14.5 of mouse development.  相似文献   
97.
We investigated the change in chlortetracycline resistance in 360 Escherichia coli strains separated from the feces of piglets fed fermented liquid feed (FLF) in comparison with those fed dry feed (control). The total amount of lactic acid bacteria in feces was 8.77x10(8)CFU/g DM at weaning, which increased to 1.23x10(12)CFU/g DM (FLF) at 28 days after weaning (P<0.001). As a result of the antibiotic susceptibility test, almost all isolates were chlortetracycline-resistant (CTC(R)) until 14 days after weaning both in the FLF and control groups. At 28 days, the CTC(R)E. coli decreased to 22.2% in the FLF group, while the proportion of resistant bacteria was 88.9% in the control group. In addition, as a result of the gene analysis, it was clarified that there is a relation between the decrease in the minimum inhibitory concentration values and the possession rate of the tetracycline-resistance gene tet(A), tet(B) and tet(D). These results show that FLF caused an increase in the number of lactic acid bacteria in the intestines, and suggested that the feeding of FLF can possibly reduce antibiotic-resistance bacteria.  相似文献   
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Single-cell pulsed-field gel electrophoresis (SCPFGE) with dual electrode pairs was developed to detect the early stage of DNA fragmentation in human sperm. The motile sperm were purified by the commonly used density-gradient centrifugation technique and subsequent swim-up. The sperm were embedded in a thin film of agarose containing bovine trypsin (20 μg/mL) and were then lysed. Prior to SCPFGE, proteolysis of DNA-binding components, such as protamine and the nuclear matrix was essential to separate the long chain fibers from the fibrous and granular fragments derived from a single nucleus. The overall electrophoretic profiles elucidated the course of DNA fragmentation. A few large fibrous fragments were observed at the beginning of the process, however, as the fragmentation advanced, the long chain fibers decreased and shortened, and, conversely, the granular fragments increased until finally almost all the DNA was shredded. Although the ejaculate contained sperm with heterogeneous stages, the purified motile sperm exhibited several dozens of uniformly elongated fibers arising from the tangled DNA at the origin, whereas a part of these fibers gave rise to fibrous fragments beyond the tip of the elongated fibers, and their numbers and sizes varied among the sperm. Conventional intra-cytoplasmic sperm injection (ICSI) usually depends on intra-operative light microscopic observation to select a sperm for injection. The present results revealed that sperm motility could not give full assurance of DNA integrity. SCPFGE is likely to serve an important role in the preoperative differential diagnosis to determine the competence of the sperm population provided for injection.  相似文献   
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