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991.
-Diuretics and ss-blockers have been shown to reduce the risk of cardiovascular morbidity and mortality in people with hypertension in long-term clinical trials. No study has compared newer more costly antihypertensive agents (calcium antagonists, ACE inhibitors, and alpha-adrenergic blockers) with diuretics for reducing the incidence of cardiovascular disease in an ethnically diverse group of middle-aged and elderly hypertensive patients. The study is a randomized, double-blind, active-controlled clinical trial designed to determine whether the incidence of the primary outcome, fatal coronary heart disease or nonfatal myocardial infarction, differs between treatment initiation with a diuretic versus each of 3 other antihypertensive drugs. Men and women aged >/=55 years with at least 1 other cardiovascular disease risk factor were randomly assigned to chlorthalidone (12.5 to 25 mg/d), amlodipine (2.5 to 10 mg/d), lisinopril (10 to 40 mg/d), or doxazosin (2 to 8 mg/d) for planned follow-up of 4 to 8 years. This report describes the baseline characteristics of the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) participants. A total of 42 448 participants were randomized from 625 sites in the United States, Canada, Puerto Rico, and the US Virgin Islands. The mean age was 67 years, with 35% aged >/=70 years. Among those randomized, 36% were black, 19% were Hispanic, and 47% were women. The sample includes a high proportion of people with diabetes (36%), patients with existing cardiovascular disease (47%), and smokers (22%). There were no important differences between the randomized treatment groups at baseline. ALLHAT will add greatly to our understanding of the management of hypertension by providing an answer to the following question: are newer antihypertensive agents similar, superior, or inferior to traditional treatment with diuretics?  相似文献   
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Objectives

This study sought to describe the current practices and compare outcomes according to the use of balloon aortic valvuloplasty (BAV) or not during transcatheter aortic valve replacement (TAVR).

Background

Since its development, aortic valve pre-dilatation has been an essential step of TAVR procedures. However, the feasibility of TAVR without systematic BAV has been described.

Methods

TAVR performed in 48 centers across France between January 2013 and December 2015 were prospectively included in the FRANCE TAVI (Registry of Aortic Valve Bioprostheses Established by Catheter) registry. We compared outcomes according to BAV during the TAVR procedure.

Results

A total of 5,784 patients have been included in our analysis, corresponding to 2,579 (44.6%) with BAV avoidance and 3,205 (55.4%) patients with BAV performed. We observed a progressive decline in the use of BAV over time (78% of procedures in 2013 and 49% in the last trimester of 2015). Avoidance of BAV was associated with similar device implantation success (97.3% vs. 97.6%; p = 0.40). TAVR procedures without BAV were quicker (fluoroscopy 17.2 ± 9.1 vs. 18.5 ± 8.8 min; p < 0.01) and used lower amounts of contrast (131.5 ± 61.6 vs. 141.6 ± 61.5; p < 0.01) and radiation (608.9 ± 576.3 vs. 667.0 ± 631.3; p < 0.01). The rates of moderate to severe aortic regurgitation were lower with avoidance of BAV (8.3% vs. 12.2%; p < 0.01) and tamponade rates (1.5% vs. 2.3%; p = 0.04).

Conclusions

We confirmed that TAVR without BAV is frequently performed in France with good procedural results. This procedure is associated with procedural simplification and lower rates of residual aortic regurgitation.  相似文献   
996.
Myelodysplastic syndromes (MDS) are characterized by chronic refractory cytopenias resulting in increased risk of infection, bleeding, and conversion to acute leukemia. In an effort to improve these cytopenias we have treated 18 patients over a 6- to 8-week period with increasing daily subcutaneous doses of recombinant human granulocyte colony-stimulating factor (G-CSF). Sixteen patients responded with improvement in neutrophil counts. On cessation of treatment these counts returned to baseline values over a 2- to 4-week period. To maintain these improved blood counts 11 patients were treated with G-CSF for more prolonged periods. Ten patients again responded with an increase in total leukocyte counts (1.6- to 6.4-fold) and absolute neutrophil counts (ANC) (3.6- to 16.3-fold), with responses persisting for 3 to 16 months. A significantly decreased risk of developing bacterial infections was noted during periods with ANC greater than 1,500/mm3 as compared with periods of time with ANC less than 1,500/mm3. Two anemic patients had a greater than 20% rise in hematocrit over the study period, and 2 additional patients had a decrease in red blood cell transfusion requirements during G-CSF treatment. Bone marrow myeloid maturation improved in 7 of 9 maintenance phase patients. Three patients progressed to acute myeloid leukemia during treatment. The drug was generally well-tolerated and no severe toxicities were noted. These data demonstrated that G-CSF administered to MDS patients by daily subcutaneous administration was well-tolerated and effective in causing persistent improvement of the neutrophil levels and marrow myeloid maturation. These effects were associated with a decreased risk of infection and, in some patients, with decreased red blood cell transfusion requirements.  相似文献   
997.
Neuronal NADPH diaphorase is a nitric oxide synthase.   总被引:82,自引:11,他引:82       下载免费PDF全文
NADPH diaphorase histochemistry selectively labels a number of discrete populations of neurons throughout the nervous system. This simple and robust technique has been used in a great many experimental and neuropathological studies; however, the function of this enzyme has remained a matter of speculation. We, therefore, undertook to characterize this enzyme biochemically. With biochemical and immunochemical assays, NADPH diaphorase was purified to apparent homogeneity from rat brain by affinity chromatography and anion-exchange HPLC. Western (immunoblot) transfer and immunostaining with an antibody specific for NADPH diaphorase labeled a single protein of 150 kDa. Nitric oxide synthase was recently shown to be a 150-kDa, NADPH-dependent enzyme in brain. It is responsible for the calcium/calmodulin-dependent synthesis of the guanylyl cyclase activator nitric oxide from L-arginine. We have found that nitric oxide synthase activity and NADPH diaphorase copurify to homogeneity and that both activities could be immunoprecipitated with an antibody recognizing neuronal NADPH diaphorase. Furthermore, nitric oxide synthase was competitively inhibited by the NADPH diaphorase substrate, nitro blue tetrazolium. Thus, neuronal NADPH diaphorase is a nitric oxide synthase, and NADPH diaphorase histochemistry, therefore, provides a specific histochemical marker for neurons producing nitric oxide.  相似文献   
998.
Abasic (AP) sites represent one of the most frequently formed lesions in DNA, and they present a strong block to continued synthesis by the replicative DNA polymerases (Pols). Here we determine the mutational specificity and the genetic control of translesion synthesis (TLS) opposite an AP site in yeast by using a double-stranded plasmid system that we have devised in which bidirectional replication proceeds from a replication origin. We find that the rate, the genetic control, and the types and frequencies of nucleotides inserted opposite the AP site are very similar for both the leading and the lagging DNA strands, and that an A is predominantly inserted opposite the AP site, whereas C insertion by Rev1 constitutes a much less frequent event. In striking contrast, in studies that have been reported previously for AP bypass with gapped-duplex and single-stranded plasmids, it has been shown that a C is the predominant nucleotide inserted opposite the AP site. We discuss the implications of our observations for the mechanisms of TLS on the leading versus the lagging DNA strand and suggest that lesion bypass during replication involves the coordination of activities of the replicative Pol with that of the lesion-bypass Pol.  相似文献   
999.
We detected circulating plasma cells (PCs) by flow cytometry in 302 patients with newly diagnosed multiple myeloma (MM) by gating on CD38+CD45- cells. The number of circulating PCs per 50 000 mononuclear cells was reported. In 80 (27%) patients, no circulating PC were seen; 106 (35%) patients had 1 to 10 and 115 (38%) patients had more than 10 circulating PCs. Median overall survival for the 302 patients was 47 months. Patients with 10 or fewer circulating PCs had a median survival of 58.7 months, whereas patients with more than 10 circulating PCs had a median survival of 37.3 months (P = .001). On multivariate analysis, the prognostic value of circulating PCs was independent of beta2-microglobulin, albumin, and C-reactive protein. There was only a weak correlation between tumor mass and circulating PCs, suggesting that the appearance of circulating PCs may be a reflection of tumor biology. We conclude that the number of circulating PCs measured by flow cytometry in patients with newly diagnosed MM is an independent predictor of survival.  相似文献   
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