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161.
The molecular epidemiological and clinical aspects of hepatitis D virus (HDV) in a unique HBV, HCV, and HDV triple virus endemic community in southern Taiwan were investigated. A total of 2,909 residents aged 45 or older were screened for hepatitis B surface antigen (HBsAg), anti-HCV antibody, and anti-HDV antibody (specifically for HBsAg-positive carriers). Factors that might be associated with HDV infection, viral nucleic acid detection, and genotyping of HBV, HCV, and HDV were investigated. The prevalence of HBsAg and anti-HCV were 12.6% (366/2,909) and 41.6% (1,227/2,909), respectively. For HBsAg carriers, 15.3% (56/366) were positive for anti-HDV assay. Living in a higher endemic district of HCV infection (odds ratio [OR] = 3.2; 95% confidence interval [CI] = 1.7-6.3), male gender (OR = 1.9; 95% CI = 1.1-3.6) and co-infection with HCV (OR = 1.8; 95% CI = 1.0-3.3) were significantly independent factors associated with HDV infection. The detection rate of HDV RNA among anti-HDV-positive patients was only 12.7% (7/55). The mean HBV titer of triple infection group was significantly lower than in the HBV/HDV co-infection group (2.23 vs 3.05 in log(10), copies/ml, P = 0.046). HCV RNA detection among the triple infection group showed 47.4% (9/19) viremia rate and viral loads of 579,121 IU/ml in median (16,803-1,551,190 IU/ml). The prevalent genotype of HBV was type B (23/25); HCV was 1b (7/9) and HDV was IIa/IIb (4/4). Only the presence of HCV RNA predicted the presence of elevated ALT significantly (OR = 25.0; 95% CI = 3.39-184.6). In conclusion, the geographical aggregation of HDV infection paralleled that of HCV infection in this community. HCV suppressed the replication of HBV among triple vital infection patients. HBV and HDV lapsed into a remission or nonreplicative phase in most cases, and HCV acted as a dominant factor in triple viral-infected individuals. Only the presence of HCV RNA was associated with elevated ALT values, but not HBV or HDV.  相似文献   
162.
Under the condition of obvious iron-overload, there is a zonal hernoeiderin (iron) deposition in hepatic lobules. The deposition is heavtest in the periporfal (zone 1) and lightest in the perivenws (zone 3) hepatocytes. However, the mechanism for this pattern of iron deposition is obscure. Hepatic tissues from control, iron-deficlent or ironoverloaded Wistar rats me used to study its pathogenesis. iron-deficiency was Induced by a low Iron regimen. Ironoverload was produced by repeated intraperitoneal injections of ferric nitrilotriace-We (Fe3+-NTA) for 1–4 months. Liver tissues of the rats were lmmunohistochemically and histochemically stained for tmnaferrin receptor (TfR), transferrin (Tf), ferritin (Ft), and iron. The staining intensity of TfR, Tf and Ft increased in hepatocytes of iron-deflctent rats and decreased in that of the iromverloaded in comparison with the control rats. TfR atalning was strong in zone 1, with gradual transition into weak staining in zone 3 hepatocytes of the rat liver. TfR located primarily on the hepatocyte membrane. Tf had both membranous and cytoplasmic distribution. Many hepatocytes in group B had strong cytoplasmic Tf staining. Conversely, only a few hepatocytes had weakly stained cytoplasmic Tf in group C. Hepatocytes and Kupffer cells were Ft positive in control rats. Ft was distributed only in the cytoplasm. The staining intensity of Ft was stronger in zone 3 than in zone 1 hepatocytes of iron-deficient rats. In iron-overloaded rats, the iron deposition was severe in zone 1 and mild in zone 3 hepatocytes. These findings suggest that uptake of iron into hepatocytes in vivo is regulated and mediated by TfR and Tf. Gradient TfR distribution from zone 1 to 3 hepatocytes and active TfR-Tf mediated iron uptake resuited in the zonal iron deposition in the hepatic lobule of iron-overloaded rats.  相似文献   
163.
研究成年大鼠脑室下区 (SVZ)神经前体细胞 (neural precursors)在黑质 -纹状体通路损伤后的反应 ,本研究用 6-羟多巴胺单侧纹状体注射以损毁黑质 -纹状体通路 ,损毁 10 d后腹腔注射 Brd U ,连续 4d,每日两次 ;在 SVZ、纹状体和黑质部位用免疫组化方法检测 Brd U、nestin以及 GFAP阳性细胞。结果显示 :(1) 6-羟多巴胺损毁黑质 -纹状体通路后 ,伤侧 SVZ的 Brd U阳性细胞数明显增多 ,并成簇分布 ;nestin和 GFAP阳性细胞数也增多 ,但以 GF AP阳性细胞增多明显 ;(2 )伤侧纹状体可见大量 Br-d U、GFAP以及少量 nestin阳性细胞分布 ,而健侧只有少量 GFAP阳性细胞 ;(3 )伤侧可见 Brd U阳性细胞在 SVZ和纹状体之间呈条带样分布 ;(4 )伤侧黑质除酪氨酸羟化酶阳性神经元减少外 ,未见 Brd U、GFAP和 nestin阳性细胞表达。上述结果表明 ,6-羟多巴胺损毁黑质 -纹状体通路后 ,SVZ神经前体细胞活动增强 ,有向纹状体迁移的趋势。  相似文献   
164.
165.
BACKGROUND AND PURPOSE: Systemic lupus erythematosus (SLE), a prototype of systemic autoimmune disease characterized by multiorgan involvement with diverse clinical and serological manifestations, principally affects women in their child-bearing years. Clinically significant hepatic abnormality as the initial presentation of SLE has rarely been reported. METHODS: Eleven patients with lupus with initial presentation of lupus-related hepatitis were included in this retrospective review. Clinical manifestation, immunological profiles, and risk factors for poor prognosis were analyzed. RESULTS: The most commonly associated clinical manifestations were found to be thrombocytopenia, leukopenia, advancing age, and presence of anti-SSA/Ro antibody and anti-thyroid antibodies. The diagnosis of SLE was delayed due to dominant hepatic abnormalities. Age greater than 50 years and marked hepatic decompensation in accordance with Child classification B and C might suggest poor prognosis (p=0.06). However, the p value was not statistically significant because of the small sample size. CONCLUSIONS: Lupus-related hepatitis, particularly in late-onset lupus, is common. In addition, the presence of anti-SSA, anti-thyroglobulin, and anti-microsomal antibodies is indicative of hepatic involvement in patients with SLE.  相似文献   
166.
A patient with plasma cell leukemia was treated with anti-interleukin (IL)-6 monoclonal antibodies (mAb) for 2 months. Using chromatography on protein A-Sepharose, anti-murine-IgG-Sepharose, anti-IL-6-mAb-Sepharose and gel filtration at pH 2.3, we have demonstrated that the anti-IL-6 mAb, by preventing the binding of IL-6 to its cell membrane receptor and its renal elimination, has induced huge amounts of IL-6 to circulate in the form of monomeric immune complexes. By using this observation, we have developed a mathematical modelling that allows the determination of the overall daily production of IL-6 in this patient, which was in the range of 15 micrograms per day. Overall in vivo production of cytokines has never been evaluated in animals or in humans before.  相似文献   
167.
We report here the molecular cloning of a newly identified preprotachykinin gene, Pptc, which specifies the sequence for a new preprotachykinin protein and bioactive peptide designated hemokinin 1 (HK-1). PPT-C mRNA was detected primarily in hematopoietic cells in contrast to the previously described Ppta and Pptb genes, which are predominantly expressed in neuronal tissues. HK-1 has several biological activities that are similar to the most studied tachykinin, substance P, such as induction of plasma extravasation and mast cell degranulation. However, HK-1 also has properties that are indicative of a critical role in mouse B cell development. HK-1 stimulated the proliferation of interleukin 7-expanded B cell precursors, whereas substance P had no effect. HK-1, but not substance P, promoted the survival of freshly isolated bone marrow B lineage cells or cultured, lipopolysaccharide-stimulated pre-B cells. N-acetyl-L-trytophan-3,5-bistrifluromethyl benzyl ester, a tachykinin receptor antagonist, increased apoptosis of these cells and in vivo administration of this antagonist led to specific reductions of the B220lowCD43 population (the pre-B cell compartment) in the bone marrow and the IgMhighIgDlow population (the newly generated B cells) in the spleen. Thus, HK-1 may be an autocrine factor that is important for the survival of B cell precursors at a critical phase of development.  相似文献   
168.
Cocaine or delta 9-tetrahydrocannabinol (THC), the major psychoactive component of marijuana, has no effect on in vitro cytotoxicity mediated by natural killer (NK) cells and cytotoxic T-lymphocytes (CTL) at concentrations similar to those observed in vivo.  相似文献   
169.
A new haplogroup pattern displayed in Fujian Han in China   总被引:1,自引:0,他引:1  
Yu M  Zhang Y  Xue Y  Chen F  Wang Q  Huang X  Wang B  Yu Y  Liu A  Ma L  Shi R  Lu F  Shi Z  Zhang Y  Cheng W  Ai Q  Xu F  Huang C  Chen B  Yang H  Kang X  Sun Y  Zhang G  Li P  Fu S 《Journal of human genetics》2002,47(2):95-98
Human Y-chromosomal binary polymorphisms have been considered to preserve the paternal genetic legacy and provide evidence on human evolution and the genetic relationships among and demographic history of different populations. To reveal the genetic origin and immigration of the Fujian Han, 13 binary markers on the Y chromosome were used to screen Fujian Han by allele-specific polymerase chain reaction. The results indicated that the M9G marker was highly prevalent (96.20%), suggesting a significant genetic drift. In addition, M122C frequency was only 22.78%, and M45A and M103T were default. The distinctive haplogroup frequencies (H1, H5, and H6/7/8) imply that the haplogroup pattern is a relatively ancestral and interim type. Received: October 13, 2001 / Accepted: December 3, 2001  相似文献   
170.
Polyamines have been previously implicated in the mediation of blood-brain barrier breakdown induced by cryogenic injury (H Koenig, AD Goldstone, CY Lu, Biochem Biophys Res Commun 116:1039, 1983). We studied acute (less than 5 minute) changes in capillary ultrastructure, microvascular permeability, and the levels of polyamines and their rate regulating synthetic enzyme ornithine decarboxylase (ODC) in rat cerebral cortex after focal cold injury. Microvascular permeability was measured by relative transport of intravenously administered fluorescein. Capillary ultrastructure was studied by quantitative stereology and morphometry after intravenous administration of horseradish peroxidase. Focal cold injury induced a 2.5-, 3.8-, 1.7-, and 1.4-fold increase in the levels of ODC, putrescine, spermidine and spermine, and a 46-fold increase in fluorescein uptake in perilesional cortex. Few capillaries in control cortex contained endocytic pits or horseradish peroxidase-positive vesicles, whereas most capillaries near lesions showed these structures. Cryoinjury induced a 5-fold increase in the relative volume of microvilli and horseradish peroxidase vesicles, a 2.3-fold increase in area of luminal endocytic pits, and a 6.3-fold increase in area of abluminal exocytic pits. The ODC inhibitor alpha-difluoromethylornithine blocked the cryoinjury-induced changes in ODC, polyamines, fluorescein uptake, and capillary ultrastructure. Putrescine negated the effect of alpha-difluoromethylornithine or capillary ultrastructure, and was previously shown to nullify the alpha-difluoromethylornithine effects on polyamines and fluorescein permeability (cited above). These data link rapid changes in ODC and polyamines to blood-brain barrier breakdown, and suggest that the abnormal permeability is associated with an acute, polyamine-mediated stimulation of microvillus formation, endocytosis, and vesicular transport in capillary endothelium.  相似文献   
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