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991.
Forty-five children with acute nonlymphoblastic leukemia in relapse received a total of 56 courses of L-asparaginase combined with vincristine and prednisone. The complete remission rate of 40% (12 of 30 trials) in patients resistant to vincristine and prednisone was almost identical to that in children still sensitive to vincristine and prednisone (42%, 11 of 26 trials). The complete remission rate of 38% (14 of 37 exposures) in those children who had not received L-asparaginase previously compared favorably with the complete remission rate in those children who had received prior L-asparaginase (47%, 9 of 19 exposures). Forty-seven of the 56 induction trials were in children with 1 or more remissions and 14 of these were in children with 3 or more prior remissions. Toxicity was minimal.  相似文献   
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995.
Sprouty proteins (Sproutys) inhibit receptor tyrosine kinase signaling and control various aspects of branching morphogenesis. In this study, we examined the physiological function of Sproutys in angiogenesis, using gene targeting and short-hairpin RNA (shRNA) knockdown strategies. Sprouty2 and Sprouty4 double knockout (KO) (DKO) mice were embryonic-lethal around E12.5 due to cardiovascular defects. The number of peripheral blood vessels, but not that of lymphatic vessels, was increased in Sprouty4 KO mice compared with wild-type (WT) mice. Sprouty4 KO mice were more resistant to hind limb ischemia and soft tissue ischemia than WT mice were, because Sprouty4 deficiency causes accelerated neovascularization. Moreover, suppression of Sprouty2 and Sprouty4 expression in vivo by shRNA targeting accelerated angiogenesis and has a therapeutic effect in a mouse model of hind limb ischemia. These data suggest that Sproutys are physiologically important negative regulators of angiogenesis in vivo and novel therapeutic targets for treating peripheral ischemic diseases.  相似文献   
996.
Normothermic machine perfusion (NMP) has been introduced as a promising technology to preserve and possibly repair marginal liver grafts. The aim of this study was to compare the effect of temperature on the preservation of donation after cardiac death (DCD) liver grafts in an ex vivo perfusion model after NMP (38.5°C) and subnormothermic machine perfusion (SNMP, 21°C) with a control group preserved by cold storage (CS, 4°C). Fifteen porcine livers with 60 min of warm ischemia were preserved for 10 h by NMP, SNMP or CS (n = 5/group). After the preservation phase all livers were reperfused for 24 h in an isolated perfusion system with whole blood at 38.5°C to simulate transplantation. At the end of transplant simulation, the NMP group showed significantly lower hepatocellular enzyme level (AST: 277 ± 69 U/L; ALT: 22 ± 2 U/L; P < 0.03) compared to both SNMP (AST: 3243 ± 1048 U/L; ALT: 127 ± 70 U/L) and CS (AST: 3150 ± 1546 U/L; ALT: 185 ± 97 U/L). There was no significant difference between SNMP and CS. Bile production was significantly higher in the NMP group (219 ± 43 mL; P < 0.01) compared to both SNMP (49 ± 84 mL) and CS (12 ± 16 mL) with no significant difference between the latter two groups. Histologically, the NMP livers showed preserved cellular architecture compared to the SNMP and CS groups. NMP was able to recover DCD livers showing superior hepatocellular integrity, biliary function, and microcirculation compared to SNMP and CS. SNMP showed some significant benefit over CS, yet has not shown any advantage over NMP.  相似文献   
997.
BACKGROUND: Interleukin (IL)-13 is a T-cell-derived cytokine that shares several functions with IL-4, including the induction of immunoglobulin E synthesis. Recent studies suggest that cytokines expressed locally in the skin play several critical roles in atopic dermatitis (AD), however, little is known about the role of IL-13 in AD lesions. OBJECTIVES: The present study was designed to characterize the involvement of IL-13 in AD in the skin and peripheral blood mononuclear cells (PBMC). METHODS: Using lesional and nonlesional skin from adult AD patients and normal skin from healthy volunteers, we performed RT-PCR, in situ RT and immunostaining to determine the IL-13 expression at the mRNA and protein levels. The actual numbers of IL-13 expressing cells in biopsy specimens were counted under the microscope. IL-13 mRNA expression in PBMC from AD patients and healthy volunteers was examined by RT-PCR analysis. RESULTS: IL-13 mRNA expression was detected by RT-PCR in lesional and nonlesional skin and in PBMC from AD patients, but not in normal skin or PBMC from healthy volunteers. In AD lesional skin, numerous IL-13 mRNA-positive cells were demonstrated by in situ RT, and similar numbers of IL-13-positive cells were also detected immunohistochemically. Smaller numbers of IL-13-positive cells were observed in AD nonlesional skin and in normal skin. The differences in the numbers of IL-13-expressing cells between lesional and nonlesional skin were statistically significant. Double immunostaining revealed that IL-13 was produced in approximately 40% of T cells and 20% of mast cells in AD lesional skin, suggesting that T cells and mast cells are major sources of IL-13 in AD lesions. CONCLUSION: IL-13 may play a local as well as a systemic role in the development of AD lesions.  相似文献   
998.
Summary The expression of transforming growth factor alpha (TGF-) was examined in various human tissues and the fetus, using immunohistochemistry and Northern blot analysis. TGF- immunoreactivity was detected mainly in the epithelial cells of the digestive tract, liver, pancreas, kidney, thyroid, adrenal, skin, mammary gland and genital organs. In the digestive tract, epithelial cells with regenerative change or hyperplastic change showed strong immunoreactivity to TGF-. Peripheral nerve, vessels, megakaryocytes and macrophages in the lung and spleen were also positive for TGF-. By Northern blot analysis the expression of TGF- mRNA was confirmed in the digestive tract, salivary gland, thyroid, kidney and mammary gland. In the human fetus, the nerve tissues, liver, adrenal and kidney were positive for TGF-. Strong immunoreactivity to TGF- was observed in the hepatocytes of the fetus. These findings indicate that TGF- is produced by a variety of nonneoplastic cells in both adult and fetal tissues.  相似文献   
999.

Objective

The purpose of this nonrandomized retrospective study was to report our new procedures using polyethylene glycolic acid (PGA) felt with fibrin sealant to prevent severe pancreatic fistula in patients undergoing pancreatic surgery.

Methods

From 2000 to 2008, 54 and 63 patients underwent pancreaticoduodenectomy (PD) and distal pancreatectomy (DP), respectively. Of those patients, we applied PGA felt with fibrin sealant to 18 PD patients and 26 DP patients. In PD patients, the PGA felt was wrapped around the pancreatic suture site, while in DP patients, the PGA felt was wrapped around the predictive division site. The pancreaticojejunostomy site in PD patients and the cut stump in DP patients were coated with fibrin sealant. We compared the occurrence rates for severe postoperative pancreatic fistula (POPF) that occurred after PD or DP both with and without our new procedures.

Results

Before introduction of our procedures, severe POPF developed in 14 of 36 PD patients (39%) and 10 of 37 DP patients (27%). In contrast, after introduction of our procedures, the incidence of POPF was only one in both of 18 PD (6%; P?=?0.016) and 26 DP (4%; P?=?0.017) patients.

Conclusion

In summary, our procedure using PGA felt with fibrin sealant may reduce the risk of severe POPF.  相似文献   
1000.
To examine the role of vascular endothelial growth factor (VEGF) in the development of edema associated with Kaposi's sarcoma (KS) in acquired immunodeficiency syndrome (AIDS), we exploited animal model systems to detect the activity that induces vascular hyper-permeability (VHP) using cultured AIDS-KS spindle cells. Cultured AIDS-KS spindle cells and conditioned medium (AIDS-KS-CM) that had been semi-purified through a heparin affinity column were tested for the ability to induce VHP in animals. The AIDS-KS spindle cells and AIDS-KS-CM induced VHP that was histamine-independent. The VHP-inducing activity was detected in the 0.5 M NaCl fraction from the heparin affinity column and was blocked by anti-VEGF neutralizing antibody. In addition, the production of VEGF was demonstrated in fresh AIDS-KS tissue as well as in cultured AIDS-KS cells, while control cells were negative for VEGF production. From these observations, we concluded that AIDS-KS cells produce a factor(s) that promotes VHP, and this factor could be VEGF.  相似文献   
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