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991.
BACKGROUND: Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by recurrent attacks of fever with serosal inflammation. FMF gene (MEFV) mutations have been identified primarily in patients from Mediterranean populations. Although several clinical cases have been reported in Japan, there have been few reports to date on mutation analysis. We studied FMF patients and their relatives to examine the clinical and genetic features of this disease in the Japanese population. METHODS: Twelve Japanese FMF patients who met the Tel Hashomer criteria and a total of 17 relatives from 5 of 10 families underwent molecular genetic studies to detect MEFV mutations. The characteristics of these Japanese FMF patients and geno-phenotypical correlations were examined. RESULTS: Almost all of our patients had been suffering for a long time from fever of unknown origin and one patient also had systemic amyloidosis. In our 12 FMF patients, we detected the substitutions E84K, L110P, E148Q, R761H and M694I. We also newly diagnosed 2 relatives as having FMF based on clinical symptoms and the existence of FMF mutations. One patient was homozygous for E148Q, the patient with systemic amyloidosis was a homozygote for M694I and 4 patients from 3 families were compound heterozygotes for E148Q and M694I. Three patients in one family were compound heterozygotes for E148Q, L110P and M694I. There were 3 patients who were heterozygous for E84K, L110P-E148Q or M694I and had no other nucleotide changes in the exons of MEFV. On the other hand, 2 relatives who had never experienced symptoms of FMF were homozygous for L110P-E148Q as well as compound heterozygous for E148Q/E148Q-R761H. E148Q and M694I were the most frequently detected substitutions in our study. CONCLUSIONS: MEFV mutations occur in Japanese FMF patients though FMF is rare in Japan. The identification of MEFV mutations could be a reliable diagnostic test for FMF. The results of genetic analyses on 14 Japanese FMF patients in this study revealed that E148Q and M694I are frequent alleles.  相似文献   
992.
A Inui  K Sano  M Miura  Y Hirosue  M Nakajima  M Okita  S Baba  M Kasuga 《Endocrinology》1992,131(5):2090-2096
The expression and structure of the receptors for neuropeptide-Y (NPY) and peptide-YY (PYY) were studied in 16 human and rodent tumor cell lines derived from the neural crest by ligand binding and cross-linking techniques using [125I]Bolton-Hunter-NPY, [125I]PYY, and various forms of monoiodinated NPY and PYY. Although NPY-binding sites were observed in most of the tumor cells, PYY-binding sites were found only on the human neuroblastoma cell lines SMS-MSN, SMS-KAN, SK-N-MC, and MC-IXC and the human Ewing's sarcoma cell line SK-ES. The differential labeling of the NPY/PYY receptors on these cell lines suggests that the NPY/PYY receptors are more heterogeneous than previously described as the Y1, Y2, and Y3 receptor subtypes. Cross-linking studies demonstrate that the Y1 and Y2 receptors for NPY/PYY are structurally different (mol wt, 70 and 50 kilodaltons, respectively) and that the 70- and 50-kilodalton receptor proteins are coexpressed in certain tumor cell lines. This could explain at least in part why cell lines show a relative specificity for Y1/Y2 classification, observed as the inhibition by both C-terminal fragments and Y1-specific analogs on the NPY/PYY binding to membrane receptors. Collectively, the present study suggests further heterogeneity of the NPY/PYY receptors and the existence of multiple receptor proteins in the tumor cell lines derived from the neural crest.  相似文献   
993.
994.
When n-octyl-beta-D-glucoside was used in several detergents to extract active avian pancreatic polypeptide (APP) receptors, a specific binding of [125I]APP to the solubilized chicken cerebellar and porcine hippocampal membranes was found. The binding of [125I]APP to the solubilized receptors was dependent on incubation time, temperature, and protein concentrations and appeared to have a slightly acidic optimal pH. APP binding to chicken and porcine brain extracts showed a high specificity for APP, although the chicken receptors do not discriminate well between APP and its related peptides, neuropeptide Y and peptide YY. Scatchard analyses of competitive binding data indicated the presence of two classes of binding sites in the brain extracts as in membrane-bound receptors; however, the high affinity component of the chicken receptor showed a decreased affinity after extraction. APP receptors in chicken and porcine brain extracts retained their insensitivity to the nonhydrolyzable GTP analog guanosine 5'-O-(3-thiotriphosphate). Cross-linking studies were performed with the homobifunctional cross-linker disuccinimidyl suberate and brain membrane receptors solubilized with n-octyl-beta-D-glucoside. An APP receptor species with a M(r) of 67,000, the same size as that of the labeled protein in native membrane homogenates of chicken and pig brains, was identified. However, in the canine brain we observed a M(r) 85,000 receptor protein, suggesting that species differences exist among the structures of brain APP receptors. The solubilized cross-linked APP receptors in these species were adsorbed by wheat germ agglutinin-agarose and by concanavalin A, indicating that they are glycoprotein in nature. The availability of the solubilized receptors from vertebrate brains with n-octyl-beta-D-glucoside represents an important step toward the purification and molecular characterization of the APP receptors.  相似文献   
995.
OBJECTIVE: A new DNA virus, which has been designated the TT virus, was discovered in 1997. It is not clear whether TT virus is a cause of any of the types of hepatitis. We conducted a case-control study to test the hypothesis that the presence of TT virus is a necessary condition for the development of fulminant hepatic failure in people who have non-A, -B, or -C hepatitis. METHODS: We studied 55 patients with fulminant hepatic failure [28 men, 27 women, mean (+/- SD) age, 47 +/- 15 yr], 32 patients with acute hepatitis (18 men, 14 women, mean age, 38 +/- 15 yr), and 200 healthy subjects (106 men, 94 women, mean age, 42 +/- 14 yr). TT virus DNA was detected in sera by a nested polymerase chain reaction using a primer set for genotype 1. RESULTS: TT virus was more frequently detected in patients with fulminant hepatic failure [in 33 of 55 (60%); 95% confidence interval (CI), 47-73%] than in those with acute hepatitis [in 8 of 32 (25%); 95% CI, 10-40%; p = 0.0016] or in healthy subjects [in 50 of 200 (25%); 95% CI, 19-31%; p < 0.0001]. TT virus was detected at a significantly higher rate in non-A, -B, or -C fulminant hepatic failure [in 18 of 22 (82%); 95% CI, 66-98%] than in fulminant hepatic failure of A, B, or C type [45%, 28-62%, 15/33; p = 0.007] or in non-A, -B, or -C acute hepatitis [24%, 3-44%, 4/17; p = 0.0003]. The logistic regression analysis selected TT virus (p = 0.0009), age (p = 0.0116), and etiology (p = 0.0309) as independent variables associated with fulminant hepatic failure (coefficient of determination, 0.2335). CONCLUSIONS: TT virus comparatively plays a role in the pathogenesis of non-A, -B, or -C fulminant hepatic failure.  相似文献   
996.
997.

Background

To compare the survival impacts of radiofrequency ablation (RFA) as an initial treatment for hepatocellular carcinoma (HCC) in patients with impaired liver functional reserve compared to those of hepatic resection (HR).

Methods

In total, 104 patients with liver damage B as defined by the Liver Cancer Study Group of Japan underwent RFA (n = 33) or HR (n = 71) as an initial treatment for hepatocellular carcinoma. The overall survival (OS) and disease-free survival (DFS) rates were compared, and independent prognostic factors were identified.

Results

The OS tended to be better in the RFA group than in the HR group. There was no significant difference in the DFS rate between the two groups. Independent poor prognostic factors for OS were tumor size >3 cm and red blood cell transfusion, and those for DFS were aspartate aminotransferase level >35 IU/L and multiple tumors. Subgroup analyses revealed that the OS with RFA was significantly better in patients with aspartate aminotransferase >35 IU/L, serum albumin <3.5 g/dL, and 99mTc-galactosyl human serum albumin <0.85.

Conclusions

RFA offers comparable results with HR and may be preferable for HCC in the particular setting of liver damage B, especially in those with poorer liver functional reserve.  相似文献   
998.
In order to establish immunological detection methods for severe acute respiratory syndrome coronavirus (SARS-CoV), we established monoclonal antibodies directed against structural components of the virus. B cell hybridomas were generated from mice that were hyper-immunized with inactivated SARS-CoV virion. By screening 2,880 generated hybridomas, we established three hybridoma clones that secreted antibodies specific for nucleocapsid protein (N) and 27 clones that secreted antibodies specific for spike protein (S). Among these, four S-protein specific antibodies had in vitro neutralization activity against SARS-CoV infection. These monoclonal antibodies enabled the immunological detection of SARS-CoV by immunofluorescence staining, Western blot or immunohistology. Furthermore, a combination of monoclonal antibodies with different specificities allowed the establishment of a highly sensitive antigen-capture sandwich ELISA system. These monoclonal antibodies would be a useful tool for rapid and specific diagnosis of SARS and also for possible antibody-based treatment of the disease.  相似文献   
999.
Helicobacter pylori infection of the gastricmucosal surface was investigated in patients withhamartomatous fundic polyps or hyperplastic polyps andin patients without endoscopic evidence of disease(healthy subjects). Presence of H. pylori infection wasdetermined by culture, histologic examination, and theendoscopic phenol red test. Adherence of H. pylori wasevaluated with scanning electron microscopic examination of antral biopsy specimens. Bothprevalence of H. pylori infection (P < 0.001) and H.pylori adherence (P < 0.05) were less in patientswith hamartomatous fundic polyps than in healthy subjects and patients with hyperplastic polyps.However, the percentages of plasma cells in gastricmucosa that contained IgA and of gastric epithelialcells that expressed Lewis b did not differsignificantly among the three groups. These findings suggestthat defense mechanisms against the attachment of H.pylori other than IgA or Lewis b antigen are present inpatients with hamartomarous fundic polyps.  相似文献   
1000.
Summary Using batroxobin, a thrombin-like enzyme found in snake venom, the effects of defibrinogenation on artificial lung metastasis in mice were studied. The role of natural killer (NK) cells in the inhibitory effects of defibrinogenation on metastasis was also investigated. Artificial lung metastasis experiments were performed by inoculating either B16-F10 cells or B16-BL/6 cells, highly metastatic strains of B16 melanoma cells, into C57BL/6 mice via the tail vein. The administration of batroxobin significantly inhibited lung metastasis, as did NK activity augmented by poly (I) · poly (C) administration. When both batroxobin and poly (I) · poly (C) were administered, lung metastasis was more markedly inhibited. When NK activity was suppressed by administration of anti-(asialo GM1) antibody, lung metastasis was markedly increased. When batroxobin was administered with anti-(asialo GM1) antibody, no inhibitory effects on lung metastasis, such as those seen with batroxobin alone, were observed. The administration of batroxobin had no effect at all on spleen lymphocyte NK activity. These results indicated that defibrinogenation due to batroxobin inhibits lung metastasis, and these effects depend on NK activity of the host.Abbreviations used NK natural killer - BU batroxobin units - FCS fetal calf serum  相似文献   
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