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41.
42.
Efficacy of grape seed proanthocyanidins on serum and heart tissue lipids in rats subjected to isoproterenol-induced myocardial injury 总被引:1,自引:0,他引:1
The present study was aimed to evaluate the preventive role of grape seed proanthocyanidins (GSPs) on serum and tissue lipid enzymes in isoproterenol (ISO)-induced myocardial injury in male Wistar albino rats. GSP was administered orally to rats (150-180 g) in three different doses, by gastric gavage (50, 100 and 150 mg/kg GSP), 6 days a week for 5 weeks. At the end of this period, all the rats, except the normal untreated rats that served as the control group, were administered ISO, 85 mg/kg subcutaneously, for 2 consecutive days to induce myocardial injury. After 48 h, rats (n=6 per group) were anesthetized with anesthetic ether, sacrificed and the levels of biochemical observations of the serum and heart tissues were performed. Biochemical assessment of myocardial injury was done by measuring the activities of serum thiobarbituric acid reactive substances and plasma lactate, which were significantly elevated in the rats administered with ISO. Further, our results suggest that prior administration of GSPs significantly maintained the cholesterol, phospholipids, triglycerides, and free fatty acids levels in serum and heart tissue of the ISO-induced myocardial injury in rats. The experiments conclude that GSPs possess cardioprotective and hypolipidemic effect on the treatment of ISO-induced myocardial injury. 相似文献
43.
The present investigation deals with the effect of the chloroform fraction composed of sterols and fatty acids isolated from Hemidesmus indicus root extract (CHI) on Salmonella enterica serovar Typhimurium (S. typhimurium)-induced cytotoxicity in a human intestinal epithelial cell line (Int 407). The optimum dose was fixed as 100 microg/mL for CHI against S. typhimurium, which was quite safe for Int 407 cells as the CD(50) concentration (50% cell death) of CHI was determined to be 500 microg/mL in the Int 407 cell line. CHI-treated S. typhimurium were 10-fold less cytotoxic and 40% less adherent to host cells than wild-type. Treatment of CHI significantly abrogated the invasion ability to 10- to 15-fold in S. typhimurium. The cells infected with CHI-treated S. typhimurium had a comparable viability to uninfected cells in the epithelial cell detachment assay. Immunofluorescence showed the CHI-treated bacteria were unhealthy and shrunken rods in comparison with the wild-type bacteria; those were firmly attached and invaded to deceased and hypertrophoid Int 407 cells. Transmission electron micrographs of Int 407 cells infected with wild bacteria showed a coat of adherent and invaded bacteria completely occupying the cytoplasm with characteristic Salmonella-containing vacuoles (SCV). Both necrotic and apoptotic type of cell death were observed in cells infected with wild-type bacteria, whereas most of the cells infected with treated bacteria were normal in morphology and a few had invaded bacteria, but the typical proliferated SCV was not observed in cells infected with CHI-treated S. typhimurium. In summary, the sterols and fatty acids present in CHI may be capable of taming S. typhimurium by suppressing its cytotoxic activity in an intestinal epithelial cell line. 相似文献
44.
45.
Plumbago zeylanica, commonly known as white leadwort, found abundantly in the plains of Bengal and southern India, was tested for its possible in vivo protective effect against cyclophosphamide-induced genotoxicity and oxidative stress in Swiss albino mice. Pretreatment with the alcoholic root extract of Plumbago zeylanica (250 and 500 mg/kg body weight orally for 5 days) significantly reduced the frequency of micronucleated polychromatic erythrocytes (MnPCEs), increased the PCE/NCE (normochromatic erythrocyte) ratio in the bone marrow, and decreased the levels of lipid peroxidation products with concomitant changes in the status of antioxidants. Both doses of Plumbago zeylanica were effective in exerting a protective effect against cyclophosphamide-induced genotoxicity and oxidative stress. 相似文献
46.
S. Devaraja K. S. Girish V. R. Devaraj K. Kemparaju 《Journal of thrombosis and thrombolysis》2010,29(1):119-126
In the recent past, a low molecular mass serine protease, the Hag-protease that caused pro-coagulant activity and as well
as local toxicity was isolated and characterized from the Hippasa agelenoides spider venom gland extract (Devaraja et al., Toxicon 52:130–138, 2008). In the current study, the pro-coagulant property
has been investigated further and the results are presented. The Hag-protease reduced the re-calcification time of citrated
human plasma. It reduced the activated partial thromboplastin time (APTT), and prothrombin time (PT) suggesting its participation
in common pathway of blood coagulation. Interestingly, it coagulated the citrated human plasma in the absence of CaCl2 but, it was lacking thrombin-like activity as it did not clot the purified fibrinogen. Strikingly, the enzyme coagulated
the factor X deficient congenital human plasma, suggesting the factor Xa-like activity. However, the cumulative augmented
activity was observed in presence of CaCl2 and phospholipids. Further, the Hag-protease preferentially hydrolyzed the Aα chain and then the Bβ-chain, but not the γ-chain.
As a result, truncated fibrinogen generated was lacking in the polymerization property. It hydrolyzed all the subunits of
partially cross-liked fibrin clot (α-polymer, α-chain, β-chain, and γ–γ dimers). Further, at low concentrations, the Hag-protease
stimulated the aggregation of human platelets in platelet rich plasma, but at high concentrations caused spontaneous clumping.
In contrast, it inhibited the collagen induced aggregation of washed human platelets. In summary, the present study for the
first time reporting the factor Xa-like activity of a serine protease especially from the spider venom that exhibited opposing
effects on hemostasis, the pro-coagulant activity and the anti-coagulant activity including fibrin(ogen)olytic and platelet
aggregation inhibition activities. 相似文献
47.
Oxidized low-density lipoprotein and atherosclerosis 总被引:1,自引:0,他引:1
Atherosclerosis is the leading cause of morbidity and mortality in western society. The most important risk factors for atherosclerosis
include smoking, hypertension, dyslipidemia, diabetes and a family history of premature atherosclerosis. Several studies indicate
that an increased plasma low density lipoprotein (LDL) cholesterol constitutes a major risk factor for atherosclerosis. Many
data support a proatherogenic role for oxidized LDL and its in vivo existence. The oxidative susceptibility of LDL is increased
with established cardiovascular risk factors, such as diabetes, smoking and dyslipidemia. Supplementation with antioxidants
such as ascorbate and alpha-tocopherol can decrease LDL oxidation as well as cardiovascular mortality and thus shows promise
in the prevention of atherosclerosis. 相似文献
48.
49.
alpha-Tocopherol supplementation decreases plasminogen activator inhibitor-1 and P-selectin levels in type 2 diabetic patients 总被引:12,自引:0,他引:12
OBJECTIVE: Type 2 diabetic subjects have an increased propensity to premature atherothrombosis. alpha-Tocopherol (AT), a potent antioxidant, has anti-inflammatory properties at high doses. The aim of the study was to test the effect of natural (RRR)-AT supplementation (1,200 IU/day) on markers of thrombosis, plasminogen activator inhibitor-1 (PAI-1), and soluble P-selectin (sP-selectin) in type 2 diabetic patients with and without macrovascular complications (MVCs) compared with matched control subjects. RESEARCH DESIGN AND METHODS: The volunteers comprised type 2 diabetic patients with (n=23) and without (n=24) MVCs and matched control subjects (n=25). Plasma levels of PAI-1 and P-selectin were assayed at baseline, after 3 months of supplementation, and after a 2-month washout phase. RESULTS: Both diabetic groups had significantly increased levels of PAI-1 compared with control subjects (P < 0.025), whereas only type 2 diabetic patients with MVCs had significantly elevated levels of sP-selectin compared with control subjects. AT supplementation significantly lowered levels of PAI-1 and sP-selectin in all three groups. The reduction in PAI-1 levels with AT supplementation was significantly greater in type 2 diabetic patients with MVCs than in those without MVCs (P=0.005). CONCLUSIONS: Thus, AT therapy decreases markers of thrombosis in diabetic patients and control subjects and could be an adjunctive therapy in the prevention of atherosclerosis. 相似文献
50.
The class B scavenger receptor, CD36, binds to oxidized LDL (OxLDL), is present in atherosclerotic lesions, and is upregulated by OxLDL or AcLDL. Previously we have shown that RRR-alpha-tocopherol (AT) enrichment of human monocyte-derived macrophages inhibited OxLDL or AcLDL induced CD36 expression. The mechanism by which AT inhibited CD36 expression is not known. In the present study, we explored the mechanism by which AT decreases CD36 expression in human macrophages. Macrophages were enriched with AT (100 microM) or N-acetyl cysteine (NAC, 6 mM) overnight and then incubated with oxLDL or AcLDL for 48 h. The effect of protein kinase C inhibitors, and tyrosine kinase inhibitors on OxLDL or AcLDL-induced CD36 expression was quantitated by flow cytometry. Protein kinase C inhibitors or NAC had no effect while there was a significant inhibition with tyrosine kinase inhibitors (P < 0.01). OxLDL or AcLDL significantly increased tyrosine kinase activity which was significantly inhibited by pre-incubation with AT or with tyrosine kinase inhibitors. Western blotting revealed an increase in Tyk2 as well as phosphotyk2 with OxLDL or AcLDL. Immunoprecipitation of CD36 followed by Western blotting with Tyk2 antibodies revealed that Tyk2 was associated with CD36. In conclusion, this study demonstrates an additional direct cellular effect of AT, i.e. inhibition of CD36 expression via inhibition of tyrosine kinase (Tyk2). 相似文献