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941.
942.
943.

Background and Aim

Preoperative cholangitis after preoperative drainage has been reported to increase postoperative complications, particularly pancreatic fistula. We therefore examined the effects of cholangitis after preoperative endoscopic biliary drainage (EBD) on postoperative pancreatic fistula in patients with middle and lower malignant biliary strictures.

Methods

The study group comprised 102 patients who underwent EBD among patients who underwent surgery.

Results

Of the 102 patients, 33 (32%) had postoperative pancreatic fistulas, and 56 (55%) had preoperative cholangitis after preoperative drainage. Analysis of risk factors for preoperative cholangitis showed that a total bilirubin level of 2.9 mg/dL or higher (hazard ratio [HR], 2.95; 95% confidence interval [CI], 1.223–7.130; P = 0.016) and a surgical waiting time of 29 days or longer (HR, 4.23; 95% CI, 1.681–10.637; P = 0.02) were independent risk factors for cholangitis. Patients with preoperative cholangitis had a significantly higher incidence of pancreatic fistula than did patients without preoperative cholangitis (78.8 vs 21.2%; P = 0.001). Patients with biliary cancer had a significantly higher incidence of pancreatic fistula than did those with pancreatic cancer (72.7 vs 27.2%; P = 0.005). Multivariate analysis showed that preoperative cholangitis (HR, 4.8; 95% CI, 1.785–12.992; P = 0.001) and biliary cancer (HR, 3.5; 95% CI, 1.335–8.942; P = 0.006) were significant independent risk factors for postoperative pancreatic fistula.

Conclusion

Prevention of preoperative cholangitis, a risk factor for postoperative pancreatic fistula, is likely to decrease the incidence of postoperative pancreatic fistula.  相似文献   
944.
The objective of this study was to investigate the clinical significance of the Wnt/β-catenin signaling pathway in glucocorticoid-induced osteoporosis. A total of 91 patients with systemic autoimmune diseases who received initial glucocorticoid therapy with prednisolone (30–60 mg daily) were prospectively enrolled. We measured serum levels of N-terminal peptide of type I procollagen (P1NP), bone alkaline phosphatase (BAP), tartrate-resistant acid phosphatase isoform 5b (TRACP-5b), N-telopeptide cross-linked type I collagen (NTX), sclerostin, Dickkopf-1 (Dkk-1), and Wnt3a before starting glucocorticoid therapy and every week for 4 weeks after its initiation. The effects of dexamethasone on expression of mRNA and protein of sclerostin and Dkk-1 by cultured normal human osteoblasts (NHOst) were evaluated by RT-PCR and ELISA, respectively. Serum levels of sclerostin and Dkk-1 increased significantly by 1 week of glucocorticoid therapy and then decreased from the second week onward. Serum Wnt3a tended to decrease and serum P1NP showed a significant decrease. However, TRACP-5b was significantly elevated from the first week of treatment onwards. In vitro study, dexamethasone increased Dkk-1 mRNA expression in cultured NHOst, but sclerostin mRNA was not detected. Dexamethasone also increased Dkk-1 protein production by osteoblasts, whereas sclerostin protein was not detected. Bone formation might be impaired at least in the first week of the initiation of glucocorticoid therapy by increase of the serum Wnt signaling inhibitors; however, their reductions in the subsequent weeks were contradictory to the maintained suppression of the bone formation markers after glucocorticoid therapy for patients with systemic autoimmune diseases.  相似文献   
945.
A part of the nucleotide sequence of the 5′ untranslated region (5′UTR) and Erns region, and the genomic regions encoding for Npro, Core, and E2 of So-like isolates and IS25CP/01 strain which belong to bovine viral diarrhea virus genotype 1 (BVDV-1) were determined and genetic comparisons were made with sequences of other BVDV subgenotypes. Phylogenetic analysis using the 5′UTR and Npro revealed that So-like isolates and IS25CP/01 branched into independent phylogenetic branch. So-like isolates were clustered with Korean BVDV strains taken from DDBL/EMBL/GenBank in the 5′UTR. An additional two amino acid residues were found at the C terminal of the Core region of IS25CP/01. The similarity of amino acid sequence of E2 of So-like isolates and IS25CP/01 to the BVDV-1 reference strain NADL were 78.0–78.5 and 79.0, respectively. Cross-neutralization tests showed significant antigenic differences between So-like isolates and the others (Antigenic similarity (R) value: 2.2–8.8), and IS25CP/01 and the others (R value: 1.6–8.8). So-like viruses and IS25CP/01 differed from the thirteenth subgenotypes (1a-1m) reported by Jackova et al. (2007) and were classified as new genetic subtypes, BVDV-1n (So-like) and 1o (IS25CP/01). The nucleotide sequence data reported in this article have been submitted to the DDBJ/EMBL/GenBank nucleotide sequence database and assigned the accession numbers AB359923–AB359944.  相似文献   
946.
The hemagglutinins (HAs) of H9 influenza viruses isolated from birds and mammals of different species were antigenically and genetically analyzed. Antigenic variants were selected from A/swine/Hong Kong/10/98 (H9N2) and A/duck/Hokkaido/13/00 (H9N2) in the presence of monoclonal antibodies (MAbs). Based on the reactivity patterns of these mutants with a panel of MAbs, at least five non-overlapping antigenic sites were defined using eight MAbs which recognized seven distinct epitopes on the H9 HA molecule. Based on the reactivity patterns with the panel of monoclonal antibodies, 21 H9N2 virus strains isolated from birds and mammals were divided into 7 antigenically distinct groups. The present findings indicate that it is important to monitor the antigenic variation in H9 influenza viruses. The panel of MAbs in the present study, thus, should be useful for detailed antigenic analysis of the H9 HAs for epidemiological studies, the selection of vaccine strains, and diagnosis.  相似文献   
947.
Carbonyl compounds I were subjected to an imidazole transfer reaction with N,N'-sulfinyldiimidazole or N,N'-carbonyldiimidazole to obtain the diimidazole II and the monoimidazole III. Various 1-vinylimidazoles IV, derived from o-hydroxyacetophenones by imidazole transfer reaction, were alkylated to furnish the title compounds V. The structure-activity relationships of these 1-vinylimidazole compounds V are described.  相似文献   
948.
949.
We have determined the H-2 class II allele-specific amino acid motif of the agretope (the site of contact between the peptide antigen and the major histocompatibility complex) for a synthetic peptide composed of residues 43-58 of pigeon cytochrome c (p43-58). Residues 46 and 54 functioned as the agretope, and residues 50 and 52 functioned as the epitope (the site for contact between the peptide antigen and the T-cell antigen receptor). In general, agretopes and epitopes function independently. Thus, substitution of amino acids in the epitope does not significantly affect binding of the peptide antigen to a class II molecule. On the basis of these findings, synthetic peptide vaccines against influenza Aichi (H3N2) virus were prepared by introducing seven residues of the influenza virus hemagglutinin into the frame component residues 43-46 and 54-58 of p43-58 analogues including the agretopes for Ak or Ab previously determined on the p43-58 segment. These peptide vaccines induced both helper T-cell responses and production of antibodies that were specific for influenza Aichi hemagglutinin but not for the major histocompatibility complex binding frame in mice bearing Ak or Ab. The antibodies produced neutralize the infectivity of influenza Aichi in vitro. The present findings should provide a basis for preparing potent peptide vaccines that function without producing side effects.  相似文献   
950.
We report herein a case of a 46 year old man presenting with a gastric ulcer in whom an endoscopy happened to detect an elevated lesion in the lower esophagus. Endoscopic biopsy proved sufficient for determining the diagnosis of a granular cell tumor (GCT). Electron and microscopic studies suggest that GCT are derived from Schwann cells. Although commonly found in the tongue and skin, GCT are rarely seen in the gastrointestinal tract, especially in the esophagus. However, advances in endoscopic techniques will increase the opportunity of detecting GCT of the esophagus.  相似文献   
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