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71.
The treatment of patients with recurrent glioblastoma remains a major oncologic problem, with median survival after progression of 7–9 months. To determine the maximum tolerated dose and dose-limiting toxicity (DLT), the combination of dasatinib and cyclonexyl-chloroethyl-nitrosourea (CCNU) was investigated in this setting. The study was designed as multicenter, randomized phase II trial, preceded by a lead-in safety phase. The safety component reported here, which also investigated pharmacokinetics and preliminary clinical activity, required expansion and is therefore considered a phase I part to establish a recommended dosing regimen of the combination of CCNU (90–110 mg/m2) and dasatinib (100–200 mg daily). Overall, 28 patients were screened, and 26 patients were enrolled. Five dose levels were explored. DLTs, mainly myelosuppression, occurred in 10 patients. Grade 3 or 4 neutropenia was recorded in 7 patients (26.9%) and thrombocytopenia in 11 patients (42.3%). No significant effect of CCNU coadministration on dasatinib pharmacokinetics was found. Median progression-free survival (PFS) was 1.35 months (95% confidence interval: 1.2–1.4) and 6-month PFS was 7.7%. In this phase I study of recurrent glioblastoma patients, the combination of CCNU and dasatinib showed significant hematological toxicities and led to suboptimal exposure to both agents.  相似文献   
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Autoimmune pancreatitis is a rare form of pancreatitis characterized by responsiveness to steroid therapy and an often relapsing disease course. The mainstay of therapy is oral corticotherapy. Associations of interstitial nephritis with various autoimmune disorders have been described. We hereby report the case of a 69-year-old Caucasian man with a 2-year history of autoimmune pancreatitis, who presented with impairment of kidney function, proteinuria, and hypertension. Renal histopathology showed severe diffuse interstitial nephritis. With oral prednisone and ACE inhibitor therapy, complete recovery of kidney function was not achieved and proteinuria persisted. Therefore, mycophenolate mofetil was initiated. After 8 weeks, serum creatinine decreased, and a nearly complete and sustained resolution of proteinuria was seen, while tapering oral steroid doses. With autoreactive T cells playing a major role in the pathogenesis of both diseases, a common etiology of pancreatitis and interstitial nephritis can be assumed, and the beneficial effects of an inhibitor of lymphocyte proliferation, such as mycophenolate mofetil, can be explained. We infer from our case that mycophenolate mofetil can be effective in the control of simultaneous autoimmune pancreatitis and interstitial nephritis.  相似文献   
74.
Butyrate, one of the major products of gut fermentation, is known to inhibit proliferation, induce apoptosis and differentiation, and increase phase II enzyme activities in tumor cells, whereas little information is available on protective effects in less-transformed colon cells. The aim of this study was to investigate whether the chemoprotective mechanism of glutathione S-transferase (GST) induction by butyrate could also play a role in earlier stages of colon carcinogenesis and whether chemoresistance of cells toward the endogenous genotoxic risk factor 4-hydroxy-2-nonenal (HNE) could be a consequence of butyrate treatment. As cell models, we used the human tumor cell lines HT29 and HT29 clone 19A, a differentiated subclone with properties resembling primary colon cells. We determined the expression of GSTP1 protein (enzyme-linked immunosorbent assay), the major GST in HT29, GSTP1 mRNA (Northern blotting), GST activity, intracellular glutathione, and total protein. The genotoxic impact of HNE (100-200 μM) was compared in butyrate-treated and nontreated cells using single-cell microgel electrophoresis. Our results show that GSTP1 mRNA, GSTP1 protein, GST activity, and total protein were increased (1.2- to 2.5-fold) and glutathione levels were maintained after 24- 72 h of incubation with 4 mM butyrate. Moreover, a marked reduction of HNE-induced genotoxicity was caused by preincubation with butyrate. Butyrate also induced the phosphorylation of extracellular signal-regulated kinases (ERK1/2, Western blotting) after 5-30 min, which indicates a regulation of GST expression by this signal pathway. Most effects were greater in HT29 parent cells than in clone cells. In conclusion, butyrate enhances expression of GST and other proteins in both cell lines, which leads to an enhanced chemoprotection, reducing the impact of HNE genotoxicity. Thus butyrate could play a role in early and later stages of cancer prevention by reducing exposure to relevant risk factors.  相似文献   
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T‐cell acute lymphoblastic leukemia is a heterogeneous malignancy originating from developing lymphocyte precursors likely due to mutations in genes regulating thymocyte differentiation. Here, we characterized mutation status of BCL11B and FLT3 genes, presumably involved in T-ALL, together with FBXW7 and NOTCH1 as known players in T-ALL in 65 pediatric T-cell acute lymphoblastic leukemia patients. We also aimed at the assessment of prognostic value of NOTCH1 and FBXW7 mutations in ALL-IC BFM 2002 protocol.FLT3 and BCL11B mutations were detected in 3% and 2% of patients, respectively. FBXW7 mutations were observed in 8% of patients, while NOTCH1 was mutated in 40%. No correlation was found between NOTCH1 and FBXW7 mutations and traditionally used clinical factors or molecular features. In total we have detected nine mutations, which have not been previously described by others. Eight of them were found in NOTCH1 and one in BCL11B gene.Observed frequencies of NOTCH1 and FBXW7 are in line with previous reports, thus confirming postulated participation of these two genes in T-ALL pathomechanism. Moreover, we report on mutation frequency of FLT3 and BCL11B, not extensively studied in T-ALL so far. Finally, we suggest a putative role of BLC11B as an oncogene in T-ALL pathogenesis.  相似文献   
77.
A total of 717 faeces samples were tested prospectively using the EntericBio Panel II® detection system (Serosep, Limerick, Ireland), in parallel with routine laboratory testing, which combines the EntericBio® system with retrospective culture of each specimen where a target is detected. Discrepancy analysis was conducted using molecular methods. The EntericBio Panel II® assay produced 585 negative and 132 positive results, namely, Campylobacter spp. (n = 66); SLT 1 and/or SLT 2 (n = 64); Salmonella spp. (n = 5); and Shigella spp. (n = 0). Three samples were positive for more than 1 target. Of these results, 4 Campylobacter spp. detections and 4 SLT 1/ SLT 2 detections remained unconfirmed, and the system failed to detect 2 Campylobacter spp. targets detected by routine laboratory detection. The sensitivity, specificity, positive predictive value, negative predictive value, and efficiency were calculated to be 98.4%, 98.7%, 93.9%, 99.7%, and 98.6%, respectively.  相似文献   
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79.

Purpose

To compare recurrence frequency and location between different types of bowel resections in Crohn’s disease patients.

Methods

This was a retrospective study of consecutive patients undergoing bowel resection for Crohn’s disease between 2006 and 2016. Type of primary operation was recorded and grouped as ileocolic resection, small bowel resection, segmental colon resection with colocolic anastomosis or colorectal anastomosis, colectomy with ileorectal anastomosis, or end stoma operation. Binary logistic regression was used to compare surgical recurrence frequency between groups. We also investigated how Crohn’s disease location at reoperations was related to the primary bowel resection type.

Results

Altogether, 218 patients with a median follow-up of 4.7 years were included in our study. Reoperation was performed in 42 (19.3%) patients. The risk of reoperation using the ileocolic resection group as reference was the following: small bowel resection (odds ratio (OR) 2.95, 95% confidence interval (CI) 1.01–8.66; P?=?0.049), segmental colon resection with colocolic or colorectal anastomosis (OR 6.20, 95% CI 2.04–18.87; P?=?0.001), colectomy with ileorectal anastomosis (OR 26.57, 95% CI 2.59–273.01; P?=?0.006), and end stoma operation (OR 4.62, 95% CI 1.90–11.26; P?=?0.001). In case of surgical recurrence, the reoperation type and location correlated with the primary bowel resection type.

Conclusions

Reoperation frequency in Crohn’s disease is lower after ileocolic resection than after other types of bowel resections. Surgical recurrence in Crohn’s disease tends to maintain the disease location of the primary operation. One third of Crohn’s patients undergoing an end stoma operation will still need new bowel resections due to recurrence.
  相似文献   
80.
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