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21.
To study the effects of sampling through cardiac catheters on indices of platelet function, we measured the levels of platelet factor 4 (PF4), beta thromboglobulin (BTG), and platelet aggregate ratio (PAR) in 10 patients with atrioventricular accessory pathway (AVNAP), six patients with primary pulmonary hypertension (PPH), and six patients with critical narrowing of the left anterior descending artery (LAD). In AVNAP and LAD patients samples were drawn simultaneously from a peripheral vein, coronary sinus, and brachial artery; in AVNAP patients samples were also obtained from the axillary vein before the coronary sinus was entered. In PPH patients samples were drawn from pulmonary artery, aorta, and a peripheral vein; in these patients the effects of an intravenous infusion of prostacyclin (PGl2) (2 to 8 ng/kg/min) on PF4, BTG, and PAR were also studied at all sampling sites. In all patients arterial, coronary sinus, pulmonary arterial, and axillary venous levels of PF4, BTG, and PAR significantly exceeded those measured in the peripheral vein. PGl2 infusion resulted in a significant decrease of PF4 at all sampling sites, while no consistent BTG changes were observed and PAR levels did not decrease in the peripheral vein. Although a considerable interpatient variability in PF4 levels was observed, a significant (r = 0.91) correlation was found in patients with AVNAP between simultaneous coronary sinus and arterial PF4 levels. The value of PF4 coronary sinus-arterial difference in LAD patients was consistently higher than that calculated in AVNAP patients (54.5 ± 28.9 vs 4.2 ± 3.8 ng/ml). In conclusion: (1) a considerable and variable degree of platelet activation occurs with catheter sampling, preventing the measurement of absolute levels of platelet metabolites; (2) among the indices examined PF4 appears the most sensitive for detecting changes in platelet activity; and (3) the measurement of coronary sinus-arterial PF4 differences may provide information on directional changes in transcardiac platelet behavior.  相似文献   
22.
In this work, we propose that for further studies of the physiopathology and treatment for inflammatory bowel diseases, an integral view of the conditions, including the triad of microbiota–heat shock proteins (HSPs)–probiotics, ought to be considered. Microbiota is the complex microbial flora that resides in the gut, affecting not only gut functions but also the health status of the whole body. Alteration in the microbiota’s composition has been implicated in a variety of pathological conditions (e.g., ulcerative colitis, UC), involving both gut and extra-intestinal tissues and organs. Some of these pathologies are also associated with an altered expression of HSPs (chaperones) and this is the reason why they may be considered chaperonopathies. Probiotics, which are live microorganisms able to restore the correct, healthy equilibrium of microbiota composition, can ameliorate symptoms in patients suffering from UC and modulate expression levels of HSPs. However, currently probiotic therapy follows ex-adiuvantibus criteria, i.e., treatments with beneficial effects but whose mechanism of action is unknown, which should be changed so the probiotics needed in each case are predetermined on the basis of the patient’s microbiota. Consequently, efforts are necessary to develop diagnostic tools for elucidating levels and distribution of HSPs and the microbiota composition (microbiota fingerprint) of each subject and, thus, guide specific probiotic therapy, tailored to meet the needs of the patient. Microbiota fingerprinting ought to include molecular biology techniques for sequencing highly conserved DNA, e.g., genes encoding 16S RNA, for species identification and, in addition, quantification of each relevant microbe.  相似文献   
23.
Ischemia is a leading causes of morbidity in giant cell arteritis (GCA). We studied circulating platelets and leukocytes in patients with GCA and with polymyalgia rheumatica. Normal healthy donors (>60 a) served as controls. Patients had a significantly greater fraction of platelets expressing P-selectin, of platelet–Nph and platelet–Mo aggregates, and of Nph and Mo expressing tissue factor. These differences were correlated with the percentage of platelets expressing P-selectin and were not influenced by clinical features or by systemic inflammation. Activated circulating leukocytes and platelets could contribute to indolent vessel inflammation and possibly to thromboembolic events in patients with systemic large vessel vasculitis.  相似文献   
24.
AIMS: To assess the effects of cardiac resynchronization therapy (CRT) in > or =80-year-old patients vs. patients <80 years, in terms of clinical, functional, and echocardiographic parameters after 12 month of CRT, survival, and incidence of arrhythmic events. METHODS AND RESULTS: The study population consisted of 1181 CRT patients (85 were > or =80 years old). They were enrolled in a national observational registry and underwent baseline evaluation and periodical follow-up visits. In the overall population, New York Heart Association class and ejection fraction (EF) improved and ventricular diameters decreased. Similar changes were observed in the two groups. In the study population, 157 patients died, 144 (13%) in the <80 years group and 13 (15%) in the > or =80 years group. There was a higher all-cause mortality (log-rank test, P = 0.015) among > or =80 years patients, with a trend towards higher sudden cardiac death (SCD) (P = 0.057), but similar non-SCD (P = 0.293). Using the combined endpoint of SCD or appropriate shock from a defibrillator for ventricular fibrillation, no significant differences resulted between groups (P = 0.455). In both groups, lower EF was associated with higher mortality. CONCLUSION: Cardiac resynchronization therapy demonstrated similar efficacy in patients aged > or =80 years and in those under 80, in terms of clinical and functional parameters and reverse remodelling. Similarly, CRT resulted in comparable effects on death for heart failure and on SCD.  相似文献   
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PurposeMalposition of the lower lid, including rounding of the lateral canthal angle, lower eyelid retraction with inferior scleral show, and ectropion, is a relatively frequent complication in the surgical treatment of skin cancer of the cheek and zygomatic areas. The tarsal strip technique, in association with a vertical vector cheek lift, is a reliable method for correcting lower lid malposition.Materials and patientsFrom January 2008 to January 2010, we treated 19 patients with lower eyelid malposition after skin cancer surgery of the cheek and zygomatic areas. To correct lower eyelid malposition, we used the tarsal strip technique and a vertical vector cheek lift in all patients.ResultsEleven patients had scleral show and eight patients had ectropion. Sixteen patients obtained satisfactory correction of the eyelid malposition in a single surgical procedure, while three patients required a second surgical step to correct the remaining scleral show. Good esthetic and functional results were achieved in all cases.ConclusionsThe surgical treatment of skin cancer of the cheek and zygomatic areas has the potential for postoperative sequelae. The tarsal strip technique, in association with a vertical vector cheek lift, is a relatively simple technique for correcting scleral show and ectropion.  相似文献   
28.
Pure erythroid leukemia (PEL) is a rare type of acute myeloid leukemia (AML) with a very aggressive clinical course. Presentation as a myeloid/erythroid sarcoma is exceedingly rare. We describe an infantile PEL presenting as a multifocal myeloid sarcoma, clinically and pathologically mimicking Ewing sarcoma/PNET family of tumors. The patient died 8 weeks after the initial presentation due to widespread disease. Our case shows that PEL needs to be considered in the differential diagnosis of small round blue cell tumors in infancy. A meticulous workup including immunohistochemistry, flow cytometry, molecular, and cytogenetic studies was required to reach the diagnosis.  相似文献   
29.
The multidrug resistance protein 1 (MRP1) is involved in multidrug resistance of cancer cells by mediating drug efflux out of cells, often in co-transport with glutathione (GSH). GSH efflux mediated by MRP1 can be stimulated by verapamil. In cells overexpressing MRP1, we have previously shown that verapamil induced a huge intracellular GSH depletion which triggered apoptosis of the cells. That phenomenon takes place in the more global anticancer strategy called “collateral sensitivity” and could be exploited to eradicate some chemoresistant cancer cells. Seeking alternative compounds to verapamil, we screened a library of natural flavonoids and synthetic derivatives. A large number of these compounds stimulate MRP1-mediated GSH efflux and the most active ones have been evaluated for their cytotoxic effect on MRP1-overexpressing cells versus parental cells. Interestingly, some are highly and selectively cytotoxic for MRP1-cells, leading them to apoptosis. However, some others do not exhibit any cytotoxicity while promoting a strong GSH efflux, indicating that GSH efflux is necessary but not sufficient for MRP1-cells apoptosis. In support to this hypothesis, structure activity relationships show that the absence of a hydroxyl group at position 3 of the flavonoid C ring is an absolute requirement for induction of MRP1-cells death, but is not for GSH efflux stimulation. Chrysin (compound 8) and its derivatives, compounds 11 and 22, exhibit a high selectivity toward MRP1-cells with a IC50 value of 4.1 μM for compound 11 and 4.9 μM for chrysin and compound 22, making them among the best described selective killer compounds of multidrug ABC transporter-overexpressing cells.  相似文献   
30.
The aim of this study was to analyse the relationship between insulin–glucose metabolism, nocturnal blood pressure dipping and nonalcoholic fatty liver disease (NAFLD) in obese adolescents without diabetes. One hundred one consecutive children, with biopsy-proven NAFLD, were included in this study. Blood samples were drawn for the analyses of liver function tests, insulin–glucose metabolism and lipid profile appraisal. An ambulatory blood pressure measurement (ABPM) was performed. Seventy-six children (75.3 %) were systolic nondippers, and 23 of them were diastolic nondippers (30.3 %). No differences were found in the anthropometric parameters between the two groups. When compared to the systolic dippers, the systolic nondippers had higher medians of mean nocturnal blood pressure, glucose at 0, 60 and 120 min in the oral glucose tolerance test (OGTT), OGTT insulin at all time points and insulin-resistance values. No correlation of histopathological features with dipping/nondipping statuses was found. Conclusions: We found an association between a nocturnal blood pressure fall and measures of insulin levels, independent of obesity, or daytime blood pressure levels, among the obese patients with NAFLD. Although no association between nondipping profiles and NAFLD was observed in our study, further studies with a longer term follow-up are needed, to better elucidate the complex link between these particular entities.  相似文献   
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