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101.
Corynebacterium species that are normally abundant on the skin and mucous membranes rarely cause infections and are susceptible to most antibiotics. The report in 1976 of four cases of sepsis at the National Institutes of Health caused by a hitherto undescribed Corynebacterium that is highly antibiotic resistant, but uniformly susceptible to vancomycin, alerted the medically oriented scientific community to the emergence of these organisms as a possible new cause of nosocomial infections. Although we have always performed antibiotic susceptibility tests on all microorganisms recovered from normally sterile body fluids, our first recovery of these organisms was in August 1977. Since then we have recovered 52 such strains from 39 patients, most frequently from the rectum, followed by the groin, blood, lesions and urine in order of predominance. Characterization by API 50 L strips revealed that most, but not all strains resemble the JK group of Riley et al. [1]. Cell wall studies and DNA base ratios further confirmed their status as corynebacteria. Hospital acquisition has been proved; cross infection between patients is the most likely mode of spread. Their recognition is necessary for optimal preventive and therapeutic care of patients with compromised host defenses.  相似文献   
102.
Multidrug-resistant sublines of Chinese hamster lung and mouse tumor cells selected for high levels of resistance to vincristine or actinomycin D have increased numbers of epidermal growth factor (EGF) receptors compared to control cells. Evidence for this increase was found in six of six resistant cell lines with the use of receptor binding or immunoprecipitation techniques. Levels of 125I-labeled EGF binding to intact actinomycin D-resistant cells derived from DC-3F or CLM-7 Chinese hamster lines are increased 3- to 10-fold compared to controls. Scatchard analysis of these data suggests that increased binding is a result of increased receptor number rather than altered affinity of receptor for ligand. Affinity-labeling and immunoprecipitation studies confirmed the finding of increased receptor amount in resistant hamster and mouse cells. Multidrug-resistant variants of DC-3F cells overproduce a plasma membrane glycoprotein (gp150-180) with several physicochemical properties that resemble those of EGF receptor. However, electrophoretic transfer blots with a polyclonal antibody to gp150-180 show that EGF receptor and gp150-180 are probably different molecules. Resistant cells described in this report manifest a normalized phenotype compared to transformed, tumorigenic, drug-sensitive parental cells. EGF receptor increase in resistant variants may be associated with this reverse transformation.  相似文献   
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Background

Concomitant moderate obstructive left main (LM) disease is associated with future cardiac events and poor prognosis in patients undergoing percutaneous intervention (PCI). Whether prognosis is similarly effected by LM disease not detected by angiography, but evident on intravascular ultrasound (IVUS) imaging, is not known. The purpose of this study was to evaluate the long-term prognosis of patients with angiographically insignificant LM coronary artery disease undergoing PCI.

Methods and results

One hundred and seven consecutive patients undergoing PCI with angiographically normal or mild LM disease had 2- and 3-dimensional IVUS imaging. IVUS images were digitized, and 3-dimensional reconstruction was performed. Percent diameter and area stenosis by angiography were 4.8% ± 3.5% and 18.2% ± 9.8%, respectively. IVUS mean luminal area and area stenosis were 17.9 ± 5.6 mm2 and 30.2% ± 14.7%, respectively. Long-term follow-up was available in 102 (95%) patients at a median of 29 (range 8-52) months. Major adverse cardiac events, defined as death (6), myocardial infarction (4), repeat PCI (13), or CABG (16), were associated with female sex (P = .04), diabetes (P = .02), angiographic minimum lumen diameter (P = .04), and IVUS minimum (P = .01) and mean (P = .01) lumen area. Multivariate predictors of late cardiac events were diabetes (hazard ratio 2.69, P = .014) and minimum lumen area by IVUS (hazard ratio 0.59, P = .015).

Conclusions

Despite being angiographically silent, LM disease detected by IVUS is an independent predictor of cardiac events and may serve as a marker for such events. These data extend the spectrum of LM disease severity and its relationship to cardiac prognosis in patients undergoing PCI.  相似文献   
105.
Current patterns of infection in multiple myeloma   总被引:2,自引:0,他引:2  
In twenty-six of fifty-five patients with multiple myeloma admitted to The Mount Sinai Hospital between January 1, 1969, and June 30, 1970, a total of twenty-nine infections were found. Gram-negative organisms accounted for 72 per cent of the thirty-nine isolates obtained from these patients. Fourteen patients had urinary tract infections with negative blood cultures (patients without septicemia), and eleven others had a total of thirteen episodes of bacteremia (patients with septicemia). The group of patients without septicemia could not be distinguished from those with septicemia in respect to age, sex, drug therapy, blood urea nitrogen and serum calcium levels, or white blood cell and differential counts. Gram-negative isolates were obtained from six of eight patients with pneumonia. Almost all the patients had low serum levels of immunoglobulins M and A (IgM and IgA). Tuberculin skin tests gave negative reactions in the eight patients tested.  相似文献   
106.
Fifty patients with severe aplastic anemia had no transfusions of blood products until just before marrow transplantation from HLA-identical family members. Of the 50, 42 are still alive 1 to 12 years after transplantation (median, 7 years). By actuarial standards, the 10-year probability of survival is 82%. Of the 42 surviving patients, 37 have Karnofsky performance status scores of 100% and 5 with chronic graft-versus-host disease have scores ranging from 50% to 90% (median, 80%). The 8 deaths were caused by early infection in 1, graft rejection in 1, acute graft-versus-host disease in 3, and chronic graft-versus-host disease in 3. All deaths occurred within two years after transplantation. The incidence of graft failure was 10%. Acute graft-versus-host disease developed in 14 of 44 patients at risk and chronic graft-versus-host disease, in 15 of 41. Risk factors for development of chronic graft-versus-host disease included increased age (p = 0.008) and presence of acute graft-versus-host disease (p = 0.001). The only factor associated with increased risk of death was development of acute graft-versus-host disease (p = 0.05). Results of this study extend our previous finding that patients with severe aplastic anemia who have transplants before the onset of transfusion-induced sensitization have an excellent probability of long-term survival and a normal life.  相似文献   
107.
108.
ObjectiveTo examine the effect of older versus younger age on change in anthropometric and metabolic measures during extended treatment of psychotic depression with sertraline plus olanzapine.MethodsTwo hundred and sixty-nine men and women aged 18–85 years with an episode of psychotic depression were treated with open-label sertraline plus olanzapine for up to 12 weeks. Participants who remained in remission following an 8-week stabilization phase were eligible to participate in a 36-week randomized controlled trial (RCT) that compared the efficacy and tolerability of sertraline plus olanzapine with sertraline plus placebo. Weight, waist circumference and plasma lipids, glucose, HbA1c, and insulin were measured at regular intervals during the acute, stabilization and randomized phases of the study. Linear mixed models were used to analyze the trajectories of anthropometric and metabolic measures.ResultsParticipants aged 60 years or older experienced less weight gain and less increase in cholesterol during the combined acute and stabilization phases of the study compared with those aged 18–59 years. At the acute-stabilization termination visit, mean weight in older participants was 6.5 lb. less than premorbid weight, whereas it was 17.9 lb. more than premorbid weight in younger participants. In the RCT, there was a significant interaction of treatment and age group for the trajectory of weight, but the post hoc tests that compared age groups within each treatment arm were not statistically significant. There were no clinically significant differences between younger and older participants in glycemic measures.ConclusionOlder patients with psychotic depression experienced less increase in weight and total cholesterol than their younger counterparts during acute and stabilization treatment with sertraline plus olanzapine. In the older group, weight gained during the acute and stabilization phases appeared to be partial restoration of weight lost during the index episode of depression, whereas weight gain in younger participants was not.  相似文献   
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