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171.
Reticulocalbin (RCN) is one member of the Ca(2+)-binding proteins in the secretory pathway and is localized in the endoplasmic reticulum. RCN may play a role in the normal behavior and life of cells, although its detailed role remains unknown. Overexpression of RCN may also play a role in tumorigenesis, tumor invasion, and drug resistance. The new antibody for human RCN is used in the distribution of RCN in normal human organs of fetuses and adults with or without inflammation. Immunohistochemical examination demonstrated a broad distribution of RCN in various organs of fetuses and adults, predominantly in the endocrine and exocrine organs. However, RCN expression was heterogeneous in each constituent cell of some organs. Among non-epithelial organs, vascular endothelial cells, testicular germ cells, neurons, and follicular dendritic cells showed strong staining. Plasma cells were the only RCN-positive cells among hematopoietic and lymphoid cells. In inflammatory conditions, RCN expression was enhanced in both epithelial and non-epithelial cells. Heterogeneous expression of RCN indicates that the amount of RCN needed for cell behavior and life may be variable, depending on each cell type and, therefore, RCN may be helpful in establishing the cell origin of neoplasms in some organs. However, further study is needed to establish the significance of RCN in tumorigenesis and in some peculiar features of neoplasms.  相似文献   
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The effects of nitrogen (N) supply restriction on the CO2 assimilation and photosystem 2 (PS2) function of flag leaves were compared between two contrastive Japanese rice cultivars, a low-yield cultivar released one century ago, cv. Shirobeniya (SRB), and a recently improved high-yield cultivar, cv. Akenohoshi (AKN). Both cultivars were solution-cultured at four N supply levels from N4 (control) to N1 (the lowest). With a reduction in N-supply, contents of N (LNC), ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO), and chlorophyll (Chl) in flag leaves decreased in both cultivars. In parallel with this, the net photosynthetic rate (P N), mesophyll conductance (g m), and stomatal conductance (g s) decreased. P N was more dominantly restricted by g m than g s. The values of P N, g m, and RuBPCO content were larger in AKN than SRB at the four N supply levels. The content of Chl greatly decreased with N deficiency, but the reduction in the maximum quantum yield of PS2 was relatively small. Quantum yield of PS2 (ΦPS2) decreased with N deficiency, and its significant cultivar difference was observed between the two cultivars at N1: a high value was found in AKN. The content ratio of Chl/RuBPCO was also significantly low in AKN. The low Chl/RuBPCO is one of the reasons why AKN maintained a comparatively high P N and ΦPS2 at N deficiency. The adequate ratio of N distribution between Chl and RuBPCO is the important prerequisite for the efficient and sustainable photosynthesis in a flag leaf of rice plant under low N-input.  相似文献   
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Insulin receptor substrate-1 (IRS-1) is the major substrate of both the insulin receptor and the IGF-1 receptor. In this study, we created IRS-1 transgenic (IRS-1-Tg) mice which express human IRS-1 cDNA under control of the mouse IRS-1 gene promoter. In the IRS-1-Tg mice, IRS-1 mRNA expression was significantly increased in almost all tissues, but its protein expression was increased in very limited tissues (epididymal fat and skeletal muscle). IRS-1-Tg mice showed glucose intolerance and significantly enlarged epididymal fat mass, as well as elevated serum TNF-α concentrations. Importantly insulin signaling was significantly attenuated in the liver of IRS-1-Tg mice, which may contribute to the glucose intolerance. Our results suggest that excess IRS-1 expression may not provide a beneficial impact on glucose homeostasis in vivo.  相似文献   
174.
Berberine chloride (1) and the structurally related compounds were assessed for the anti-human cytomegalovirus (HCMV) activity using the plaque assay. The anti-HCMV activity (IC(50) 0.68 microM) of 1 was equivalent to that (IC(50) 0.91 microM) of ganciclovir (GCV). The mechanism of action by which 1 inhibits the replication of HCMV is presumed to be different from that of GCV; 1 would interfere with intracellular events after virus penetration into the host cells and before viral DNA synthesis.  相似文献   
175.
A feasibility test of a 17 m3-pilot-scale sewage treatment system was carried out by continuous feeding of raw municipal sewage under ambient temperature conditions. The system consisted of a UASB and an aerated fixed bed reactor. Some of the effluent from the fixed bed reactor was returned to the UASB influent in order to provide a sulfate source. The total BOD of 148-162 mg l(-1) in the influent was reduced to a more desirable 11-25 mg l(-1) in the final effluent. The levels of methane-producing activity from acetate and H2/CO2 gas at 10 degrees C were only 2% and 0% of those at 35 degrees C, respectively. On the other hand, the sulfate-reducing activity levels of the UASB sludge were relatively high at 10 degrees C, for example, 18% for acetate and 9% for H2/CO2 gas, compared to the activity levels at 35 degrees C. Therefore, BOD oxidization by sulfate reduction in the UASB was greater than that by methane production under low temperature conditions. This sulfate-reducing activity tended to be proportional to the copy number of adenosine-5'-phosphosulfate (APS) reductase genes in DNA extracted from the sludge.  相似文献   
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BACKGROUND: Associations between Helicobacter pylori gene diversity and gastric cancer have not been reported on in Costa Rica, despite its being one of the countries with the highest gastric cancer incidence and mortality rates in the world. The aim of this study was to determine the prevalence of H. pylori cagA and vacA genes and investigate whether it could be correlated with atrophic gastritis (AG) and gastric cancer (GC) in Costa Rica. MATERIALS AND METHODS: Genomic DNAs from isolates of 104 patients classified into two groups: non-atrophic gastritis group (n = 68) and atrophic gastritis group (n = 36), were subjected to PCR-based genotyping of cagA and vacA genes and their correlation with clinical outcome was investigated. Total DNA extractions from gastric tissues of 25 H. pylori-infected gastric cancer patients were utilized for comparative purposes. RESULTS: The presence of cagA (75.3%), vacA s1b (75.3%), and vacA m1 (74.2%) was detected, and colonization by strains with different vacA genotypes in the same stomach was found in 9.7% of the patients. Age- and sex-adjusted vacA s1b and vacA m1 were associated with GC while only vacA m1 was significantly associated with AG. A tendency for association between cagA and vacA s1b, and AG was reported. CONCLUSIONS: The prevalence status of the cagA and vacA (s1/m1) genes in Costa Rica seems to fall between that found in European/North American and East Asian countries, and both cagA and vacA seem to have clinical relevance in this country.  相似文献   
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Kim  Hee-Jin  Araki  Takumi  Suematsu  Yumi  Satuito  Cyril Glenn 《Hydrobiologia》2022,849(3):747-761
Hydrobiologia - During larval development of the intertidal barnacle Fistulobalanus albicostatus, larvae in the naupliar stages I and II (NI&II) possess a single naupliar eye, and later...  相似文献   
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