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991.
992.
Although uncommon in the United States, cryptosporidiosis can be life-threatening in an immunosuppressed host. Rarely, an acute infection of this gastrointestinal illness can present as another disease entity. We present only the third reported case of cryptosporidial infection presenting as acute appendicitis in a 17-year-old HIV+ patient.  相似文献   
993.
In human obesity, the stroma vascular fraction (SVF) of white adipose tissue (WAT) is enriched in macrophages. These cells may contribute to low-grade inflammation and to its metabolic complications. Little is known about the effect of weight loss on macrophages and genes involved in macrophage attraction. We examined subcutaneous WAT (scWAT) of 7 lean and 17 morbidly obese subjects before and 3 months after bypass surgery. Immunomorphological changes of the number of scWAT-infiltrating macrophages were evaluated, along with concomitant changes in expression of SVF-overexpressed genes. The number of scWAT-infiltrating macrophages before surgery was higher in obese than in lean subjects (HAM56+/CD68+; 22.6 +/- 4.3 vs. 1.4 +/- 0.6%, P < 0.001). Typical "crowns" of macrophages were observed around adipocytes. Drastic weight loss resulted in a significant decrease in macrophage number (-11.63 +/- 2.3%, P < 0.001), and remaining macrophages stained positive for the anti-inflammatory protein interleukin 10. Genes involved in macrophage attraction (monocyte chemotactic protein [MCP]-1, plasminogen activator urokinase receptor [PLAUR], and colony-stimulating factor [CSF]-3) and hypoxia (hypoxia-inducible factor-1alpha [HIF-1alpha]), expression of which increases in obesity and decreases after surgery, were predominantly expressed in the SVF. We show that improvement of the inflammatory profile after weight loss is related to a reduced number of macrophages in scWAT. MCP-1, PLAUR, CSF-3, and HIF-1alpha may play roles in the attraction of macrophages in scWAT.  相似文献   
994.
Giardiosis in domestic ruminants is an important parasitic disease and it has been shown to impair growth in lambs, thus constituting a disease of economic concern. In Europe, surveys on the prevalence of giardiosis in sheep are limited. In order to obtain additional information on the presence of giardiosis and on the potential zoonotic role of Giardia duodenalis affecting sheep in central Italy, faecal samples of 325 native sheep from 20 farms in Abruzzo region (Italy) were examined for the presence of Giardia and the isolates were genotyped and sequenced. G. duodenalis cysts were detected in five of the 325 sheep (1.5%) (mean of 450 cysts/g) coming from two farms. The 770-bp fragment of the glutamate dehydrogenase gene and the 753-bp fragment of the -giardin gene showed 100% homology with the Assemblage AI. This work suggests for the first time in Italy that sheep carry a Giardia genotype, which can be a potential public health hazard.  相似文献   
995.
In the framework of the continuing interest of this research group in the use of 8-aryl-8-hydroxy-8H-[1,4]thiazino[3,4-c][1,2,4]oxadiazol-3-ones (1) as calcium entry blockers, a number of acetals were synthesized and assayed "in vitro". All of them are structurally related to diltiazem and pyrrolobenzothiazines. The effect on the biological profile was measured by functional assays for a wide variety of acetal residues: saturated linear and branched chains, short and long unsaturated E and/or Z chains as well as benzyl and methylcyclohexyl residues. From selective assays on the most active derivative (5b) (EC(50) = 0.04 microM), which is 20 times more active than diltiazem (EC(50) = 0.79 microM), a muscarinic or adenosinic mechanism of action was excluded. A 3D QSAR model was obtained and validated with homologous literature data, and a virtual receptor scheme was derived for the unknown binding site. The following pharmacophoric features favorably affect the potency: one positively charged center, three lipophilic groups, and two hydrogen-bonding acceptor groups.  相似文献   
996.
Atypical retinoids (AR) represent a class of proapoptotic agents with promising potential in the treatment of neoplastic diseases. In the present work 4'-hydroxybiphenyl-4-ylacrylic acids were studied as a novel series of AR. The synthesized compounds were evaluated for their antiproliferative activity in a human promyelocytic leukemia cell line (NB4) and in an ovarian carcinoma cell system including IGROV-1, carrying a functional wild-type p53, and a cisplatin-resistant subline, IGROV-1/Pt-1. The presence of a bulky lipophilic group at position 3' (adamantan-1-yl being the best) and the E configuration of the acrylic moiety appear essential for activity below 1 muM. No substitution on the rings or on the double bond improved the activity. A qualitative correlation between the log P and molecular volume of the 3'-substituent and the antiproliferative activity was found. From the study of a few selected compounds, it appears that the presence of the carboxylic group is an essential requirement for apoptogenic properties but not for antiproliferative activity, this being maintained in amide derivatives. On the other hand, compounds able to induce apoptosis produced a detectable level of genotoxic damage. This observation supports the hypothesis that the genotoxic stress is a critical event mediating apoptosis induction by compounds of this class. Among the compounds investigated, E-3-(3'-adamantan-1-yl-4'-hydroxybiphenyl-4-yl)acrylic acid (2) was chosen for further investigation.  相似文献   
997.
A novel protein encoded by the BFRF1 gene of the Epstein-Barr virus was identified recently [Farina et al. (2000) J Virol 74:3235-3244], which is antigenic "in vivo" and expressed early in the viral replicative cycle. In the present study, its subcellular localization was examined in greater detail comparing Epstein-Barr virus (EBV) induced producing and nonproducing cell lines by immunofluorescence: in 12-0-tetradecanoyl phorbol-13-acetate (TPA)-induced Raji and B95-8 cells, as well as in anti-IgG-stimulated Akata cells, the protein appeared to be localized over the cell nuclear membrane. A similar nuclear membrane localization was observed in epithelial cells of oral hairy leukoplakia, a pathological manifestation of permissive EBV infection. In contrast, upon transfection of BFRF1 in the EBV-negative Burkitt's lymphoma cell line DG75, the protein was localized predominantly over the plasma membrane. The membrane localization was abolished when DG75 cells were transfected with a C-terminal deletion mutant of BFRF1 lacking the transmembrane domain. Because induced Raji cells do not produce virus, the above observations indicate that the nuclear membrane localization is not associated with viral production, but requires the expression of EBV genes, and suggest that additional proteins, expressed early during viral lytic infection, might be necessary to target the protein to the nuclear membrane. Immunogold electron microscopy on ultrathin cryosections of induced B95-8 cells showed that BFRF1 on the nuclear membranes was concentrated over multilayered domains representing areas of active viral replication or at the sites of viral budding, suggesting that BFRF1 is involved in the process of viral assembly.  相似文献   
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