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121.
Hepatitis B and C markers were tested in 980 pregnant women, in the infants born to infected mothers, and in a random sample of 42 and 50, respectively, children born to uninfected mothers in Tanzania. Sixty-two women (6.3%) were positive for HBsAg and 15 (24%) were HBeAg-seropositive. Anti-HCV was detected in 49 women (5%), 15 (31%) of whom had detectable viremia. HCV RNA serum levels were low and only genotype 4 was identified. Sixty-six women (6.7%) were positive for anti-HIV, six of whom were coinfected with HBV and one with HCV. Anti-HEV was negative in the 180 women tested. At 8 months of age, HBsAg was detected in 8% and 2% of children born to HBV-infected and noninfected mothers, respectively (P = 0.2). Corresponding figures at 18 months of age were 31% and 21% (P = 0.3). When tested at 2 months of age, HCV RNA was not detected in any of the 43 children born to anti-HCV-positive mothers nor in any of 50 children born to anti-HCV-negative mothers. At 18 months, only one child, born to an anti-HCV-positive mother, had detectable HCV RNA. None of the infants born to women with HIV coinfection were infected with hepatitis viruses. This study suggests that exposure to HEV does not occur in southern Tanzania. The prevalence of current HBV infection in pregnant women from rural Tanzania is lower than in other sub-Saharan areas. In early childhood, HBV infection appears to occur by horizontal rather than maternofilial mechanisms of transmission. The prevalence of HCV infection is similar to that in other African countries. The results of this study show for the first time in Africa that mother-to-infant transmission does not play a significant role in the acquisition of HCV infection.  相似文献   
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123.
Several clinical trials have shown the beneficial effects of statins in the prevention of coronary heart disease. Additionally, statins promote apoptosis in vascular smooth muscle cells, in renal tubular epithelial cells and also in a variety of cell lines; yet, the effects of statins on cardiac fibroblast and myofibroblast, primarily responsible for cardiac tissue healing are almost unknown. Here, we investigated the effects of simvastatin on cardiac fibroblast and myofibroblast viability and studied the molecular cell death mechanism triggered by simvastatin in both cell types.

Methods

Rat neonatal cardiac fibroblasts and myofibroblasts were treated with simvastatin (0.1-10 μM) up to 72 h. Cell viability and apoptosis were evaluated by trypan blue exclusion method and by flow cytometry, respectively. Caspase-3 activation and Rho protein levels and activity were also determined by Western blot and pull-down assay, respectively.

Results

Simvastatin induces caspase-dependent apoptosis of cardiac fibroblasts and myofibroblasts in a concentration- and time-dependent manner, with greater effects on fibroblasts than myofibroblasts. These effects were prevented by mevalonate, farnesylpyrophosphate and geranylgeranylpyrophosphate, but not squalene. These last results suggest that apoptosis was dependent on small GTPases of the Rho family rather than Ras.

Conclusion

Simvastatin triggered apoptosis of cardiac fibroblasts and myofibroblasts by a mechanism independent of cholesterol synthesis, but dependent of isoprenilation of Rho protein. Additionally, cardiac fibroblasts were more susceptible to simvastatin-induced apoptosis than cardiac myofibroblasts. Thus simvastatin could avoid adverse cardiac remodeling leading to a less fibrotic repair of the damaged tissues.  相似文献   
124.
Kinins mediate their cellular effects through B1 (B1R) and B2 (B2R) receptors, and the activation of B2R reduces collagen synthesis in cardiac fibroblasts (CF). However, the question of whether B1R and/or B2R have a role in cardiac myofibroblasts remains unanswered.

Methods

CF were isolated from neonate rats and myofibroblasts were generated by an 84 h treatment with TGF-β1 (CMF). B1R was evaluated by western blot, immunocytochemistry and radioligand assay; B2R, inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS), and cyclooxygenases 1and 2 (COX-1, and COX-2) were evaluated by western blot; intracellular Ca+ 2 levels were evaluated with Fluo-4AM; collagen secretion was measured in the culture media using the picrosirius red assay kit.

Results

B2R, iNOS, COX-1 and low levels of B1R but not eNOS, were detected by western blot in CF. Also, B1R, B2R, and COX-2 but not iNOS, eNOS or COX-1, were detected by western blot in CMF. By immunocytochemistry, our results showed lower intracellular B1R levels in CF and higher B1R levels in CMF, mainly localized on the cell membrane. Additionally, we found B1R only in CMF cellular membrane through radioligand displacement assay. Bradykinin (BK) B2R agonist increased intracellular Ca2+ levels and reduced collagen secretion both in CF and CMF. These effects were blocked by HOE-140, and inhibited by L-NAME, 1400W and indomethacin. Des-Arg-kallidin (DAKD) B1R agonist did not increase intracellular Ca2+ levels in CF; however, after preincubation for 1 h with DAKD and re-stimulation with the same agonist, we found a low increase in intracellular Ca2+ levels. Finally, DAKD increased intracellular Ca2+ levels and decreased collagen secretion in CMF, being this effect blocked by the B1R antagonist des-Arg9-Leu8-kallidin and indomethacin, but not by L-NAME or 1400 W.

Conclusion

B1R, B2R, iNOS and COX-1 were expressed differently between CF and CMF, and collagen secretion was regulated differentially by kinin receptor agonists in cultured CF and CMF.  相似文献   
125.
Platelet-rich plasma (PRP) is used as a source of growth factors to stimulate and accelerate bone formation and soft tissue healing. The use of PRP in bone regeneration, both around dental implants and in periodontic treatments, has become particularly appealing. The aim of this study was to evaluate the effect of PRP in an experimental model of osteogenesis around laminar implants. Fifteen male Wistar rats, weighing 90 +/- 10 g, were used in this study. One milliliter of blood was obtained from each animal by intracardiac puncture and transferred into Eppendorf tubes containing 10% sodium citrate. The tubes were centrifuged at 1500 rpm for 15 minutes and PRP was prepared. The laminar test was used to evaluate the bone peri-implant response. PRP and a titanium laminar implant were introduced into the right tibia (Ti/PRP group), whereas the left tibia (control) received only a laminar implant (Ti group). Thirty days postimplantation, the tibiae were resected, radiographed, and processed for embedding in acrylic resin. Ground sections (50 microm) were stained with toluidine blue. The peri-implant bone volume was evaluated histomorphometrically. Statistical analysis of the data was performed. The amount of newly formed bone in the Ti/PRP group (30 +/- 7 cm) was significantly greater than in the Ti group (16 +/- 3 cm). A greater volume of peri-implant bone was observed when PRP was used in the laminar implant test model.  相似文献   
126.
A woman with a 5-year history of unilateral orofacial granulomatosis required repeated evaluations (including sequential colonoscopies) to establish the diagnosis of cutaneous Crohn's disease, a condition that proved responsive to low doses of oral methotrexate administered weekly. To our knowledge this is the first report describing the use of methotrexate for treatment of orofacial granulomatosis caused by underlying Crohn's disease.  相似文献   
127.
The 2004 discovery of EGFR mutations, followed by ALK rearrangements, ushered in a targeted therapy era for advanced non-small cell lung cancer (NSCLC). Tyrosine kinase inhibitors targeting gene alterations have substantially improved survival and quality of life for patients with NSCLC. In the last decade, rearrangements of the ROS1 oncogene have been incorporated into healthcare practice that are applicable to another small subgroup of patients who benefit from similar targeted strategies. Recent genome studies of lung adenocarcinoma have identified other possible therapeutic targets, including RET, NTRK fusions, c-MET alterations, and activating mutations in KRAS, BRAF, and HER2, all with frequencies greater than 1%. Lung cancers harbouring these genome changes can potentially be treated with agents approved for other indications or under clinical development. This review updates the therapeutic arsenal that especially targets those genes.  相似文献   
128.
129.
ObjectiveTo investigate the neurotransmitter enzyme Acetylcholinesterase (AChE) activity in the brain and blood of rats infected with Trypanosoma congolense (T. congo).MethodsPresence and degree of parasitemia was determined daily for each rat by the rapid matching method. AChE activity was determined by preparing a reaction mixture of brain homogenate and whole blood with 5, 5-dithiobisnitrobenzioc acid (DTNB or Ellman's reagent) and Acetylthiocholine (ATC). The increase in absorbance was recorded at 436 nm over 10 min at 2 min intervals. Trypanosome species identification (before inoculation and on day 10 post infection) was done by Polymerase chain reaction using specific primers.ResultsThe AChE activity in the brain and blood decreased significantly as compared with the uninfected control. The AChE activity dropped to 0.32 from 2.20 μmol ACTC min?1mg protein?1 in the brain and 4.57 to 0.76 μmol ACTC min-1mg protein?1 in the blood. The animals treated with Diminaveto at 3.5 mg/kg/d were observed to have recovered significantly from parasitemia and were able to regain AChE activity in the blood but not in the brain as compared to the control groups. We also observed, that progressive parasitemia resulted to alterations in PCV, Hb, RBC, WBC, neurophils, total protein, lymphocytes, monocytes and eosinophil in acute infections of T. congo. Polymerase chain reaction (PCR) of infected blood before inoculation and on day 10 post infection revealed 600 bp on agarose gel electrophoresis.ConclusionsThis finding suggest that decrease in AChE activity increases acetylcholine concentration in the synaptic cleft resulting to neurological failures in impulse transfer in T. congo infection rats.  相似文献   
130.
In a multicentre randomised, unblinded patient preference pilot trial to assess the feasibility of a definitive randomised trial comparing colposuspension with tension-free vaginal tape (TVT) plus anterior repair in women with incontinence and prolapse, we found that 31 of 56 eligible women agreed to participate (55%). Recruitment was more successful face to face (87%) than by letter (16%). Only four of our women agreed to be randomised, 21 (68%) chose anterior repair + TVT and six (19%) chose colposuspension. This study demonstrates the importance of pilot work for complex trials to identify issues likely to adversely affect recruitment.  相似文献   
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