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101.
Fungal infections are definitely increasing in neutropenic patients with hematologic malignancies. In view of a previous report on a likely correlation between nose cultures positive for Aspergillus spp. and pulmonary aspergillosis, a retrospective study on 306 consecutive neutropenic patients was performed. Twenty-six patients had one or more nose cultures positive for Aspergillus: thirteen of them developed pulmonary aspergillosis. On the other hand, only twenty out of the remaining 280 patients with negative nose cultures developed this fungal pneumonia (p less than 0.00001). Even if negative results do not obviously exclude the possibility of invasive aspergillosis, nose cultures positive for Aspergillus might prove helpful in predicting this fungal infection in febrile neutropenic patients.  相似文献   
102.
The effect of acute administration of amiodarone, its major metabolite desethylamiodarone and iodine in an amount equal to that contained in amiodarone on serum thyroid hormone and thyrotropin (TSH) concentrations and hepatic and pituitary 5' deiodination of thyroxine (T4) in the euthyroid and hypothyroid rat was evaluated. Amiodarone, desethylamiodarone and iodine all caused a decrease in serum T4 and triiodothyronine (T3) concentrations in euthyroid rats, while serum TSH concentrations and pituitary and hepatic 5' deiodinase activities were decreased only in the amiodarone and desethylamiodarone-treated animals. Serum TSH was increased in the iodine treated rats. Amiodarone, but not iodine, decreased serum T3 and TSH concentrations and pituitary and hepatic 5' deiodinase activities in hypothyroid rats. Inhibition of hepatic 5' deiodinase activity was also observed by the addition of amiodarone in vitro in the absence of dithiothreitol (DTT) but not in the presence of DTT. The decrease in the serum T4 concentration observed with amiodarone and desethylamiodarone administration is probably secondary to the inhibitory effect of iodine released from the drugs on thyroidal T4 synthesis and secretion. Iodine inhibition of thyroidal T3 synthesis and secretion, decreased T4 substrate for a peripheral generation of T3 and inhibition of T4 to T3 conversion all contribute to the decrease in serum T3 observed. The decrease in the serum TSH concentration, despite low serum T4 and T3 concentrations and inhibition of pituitary 5' deiodinase, suggest that amiodarone may function as a thyroid hormone agonist in the pituitary.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
103.
Estimates of the extent of hepatic fibrosis and the rate of fibrosis progression represent important surrogate end points for evaluation of the vulnerability of an individual patient and for assessment of the impact of treatment on natural history in chronic hepatitis C. Using the median fibrosis progression rate, the median expected time to cirrhosis in untreated patients is around 30 years. However, one third of patients have an expected median time to cirrhosis of less than 20 years and one third will only progress to cirrhosis in more than 50 years, if ever. Factors independently associated with fibrosis progression are duration of infection, age, male gender, consumption of alcohol, human immunodeficiency virus co-infection, and low CD4 count. Evaluation of fibrosis progression is useful to decide treatment. Among patients with sustained viral response, fibrosis regresses. Evaluation of fibrosis progression has permitted validation of the concept of suppressive therapy. Among patients without viral clearance, interferon alone or in combination with ribavirin significantly reduces fibrosis progression rate in comparison with progression before treatment and to control groups. There is a major need for noninvasive markers of liver fibrosis. None are clearly useful today for the diagnosis of early stages of fibrosis.  相似文献   
104.
To assess the flow characteristics of homograft valved conduits in the immediate postoperative period, 69 children with 71 homograft conduits underwent 2-dimensional and Doppler echocardiographic examination at 1 to 40 days (mean 8) after surgery. Of the 71 conduits studied, 19 were aortic and 52 were pulmonary homograft valved conduits. Two aortic homograft valved conduits were inserted in the aortic position, whereas all remaining homografts were placed in the pulmonary position. On the immediate postoperative echocardiogram, 25 (35%) of the conduit valves had no regurgitation and 44 (62%) had 1+ (mild) regurgitation. Two pulmonary valved conduits (3%) in the pulmonary position had 2+ (moderate) regurgitation and right ventricular dimensions greater than 95% for body surface area. The peak velocity across the homograft valve was normal (less than 1.3 m/s) in 58 valves (82%). In the remaining 13 valves, peak velocity ranged from 1.4 to 2.6 m/s. No homograft valve had a peak velocity greater than 2.6 m/s in the immediate postoperative period. To assess the fate of homograft valved conduits in the intermediate-term follow-up period, 38 children with 38 conduits had a repeat echocardiogram at 6 to 25 months (mean 15 +/- 6) after surgery. Of the 38 conduits examined, 10 (26%) had no regurgitation, 25 (66%) had 1+ regurgitation and 3 (8%) had 2+ regurgitation. Progression of the amount of regurgitation occurred in 11 (29%) patients. At the follow-up examination, peak velocity was less than or equal to 1.4 m/s across 34 conduit valves, between 1.4 and 2.6 m/s across 3 valves and greater than 2.6 m/s across 1 valve.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
105.
Allogeneic stem cell transplantation (allo-SCT) after a reduced-intensity conditioning (RIC) protocol is associated with decreased short-term toxicity. This suggests that the procedure could be performed on an outpatient basis. We analysed the incidence and risk factors of grade >or=2 conditioning-related toxicities (CRTs) as a hallmark for hospital admission, in 41 consecutive patients allografted from an HLA identical sibling after RIC. The RIC regimen consisted of fludarabine plus melphalan for lymphoid malignancies, and fludarabine plus busulphan for myeloid malignancies. In all, 11 patients (27%) did not experience any toxicity. The more frequent CRTs observed were neutropenic fever and gastrointestinal toxicity. The median duration of hospitalisation was 27 (range, 17-50) days. If allo-SCT had been planned as an outpatient procedure and admission indicated only in the case of >or=2 CRTs, the inpatient period would have decreased to 9 (range, 0-33) days (P<0.001). No risk factors for CRTs were identified. Allo-SCT after an RIC regimen is a well-tolerated procedure. Our results warrant a prospective pilot trial of nonmyeloablative allo-SCT performed in the outpatient setting.  相似文献   
106.
The aim of this study is to evaluate the possible role of carbohydrate-antigen(CA)-125 as prognostic marker at short- and long-term follow-up, in subjects with Takotsubo cardiomyopathy (TTC). Sixty-three consecutive subjects with TTC were enrolled in the study and followed for a median 139 days. Circulating levels of CA-125, NT-proBNP, and left ventricular ejection fraction (LVEF) were evaluated at admission. Duration of hospital stay, incidence of death, re-hospitalization and recurrence of TTC during follow-up were recorded. The mean hospital stay was 8.3 days, adverse events occurred during follow up in 17 % of cases. CA-125 levels at admission are inversely related to LVEF (r ?0.30, p < 0.05) and directly related to hospital stay (r 0.29, p < 0.05). CA-125 levels at admission are higher in subjects with adverse events at follow-up (88.9 ± 200.0 vs 20.9 ± 30.0 U/mL, p < 0.05). Rates of incidence of adverse events are proportionally increased with CA-125 tertiles (0, 6, 11 % respectively, p for trend <0.01), at survival analysis (Log Rank p < 0.05) and after correction for age, gender, LVEF and NT-proBNP levels in multivariable Cox analysis (p < 0.05). CA-125 levels <10 U/ml are predictors of adverse events at follow up with 91 % sensitivity, 52 % specificity, 29 % positive predictive power, and 96 % negative predictive power. Increased CA-125 admission levels are associated with a longer hospital stay, a lower LVEF, and a higher risk of adverse events during follow up. CA-125 might be useful for early risk stratification of subjects with TTC.  相似文献   
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