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141.
OBJECTIVES: We sought to determine the effect of diabetes mellitus (DM) on left ventricular (LV) filling pattern in normotensive (NT) and hypertensive (HTN) individuals. BACKGROUND: Diastolic abnormalities have been extensively described in HTN but are less well characterized in DM, which frequently coexists with HTN. METHODS: We analyzed the transmitral inflow velocity profile at the mitral annulus in four groups from the Strong Heart Study: NT-non-DM (n = 730), HTN-non-DM (n = 394), NT-DM (n = 616) and HTN-DM (n = 671). The DM subjects were further divided into those with normal filling pattern (n = 107) and those with abnormal relaxation (AbnREL) (n = 447). RESULTS: The peak E velocity was lowest in HTN-DM, intermediate in NT-DM and HT-non-DM and highest in the NT-non-DM group (p < 0.001), with a reverse trend seen for peak A velocity (p < 0.001). In multivariate analysis, E/A ratio was lowest in HTN-DM and highest in NT-non-DM, with no difference between NT-DM and HTN-non DM (p < 0.001). Likewise, mean atrial filling fraction and deceleration time were highest in HTN-DM, followed by HTN-non-DM or NT-DM and lowest in NT-non-DM (both p < 0.05). Among DM subjects, those with AbnREL had higher fasting glucose (p = 0.03) and hemoglobin A1C (p = 0.04). CONCLUSIONS: Diabetes mellitus, especially with worse glycemic control, is independently associated with abnormal LV relaxation. The severity of abnormal LV relaxation is similar to the well-known impaired relaxation associated with HTN. The combination of DM and HTN has more severe abnormal LV relaxation than groups with either condition alone. In addition, AbnREL in DM is associated with worse glycemic control.  相似文献   
142.
143.
Rothberger  H; Dove  FB; Lee  TK; McGee  MP; Kardon  B 《Blood》1983,61(4):712-717
The present experiments examine leukocyte procoagulant activity using mononuclear cell populations purified or enriched from rabbit bone marrow, blood, spleen, lymph node, thymus, and pulmonary alveoli. Cells from these six sites, obtained from control and endotoxemic animals and assayed without an intermediate culture step, were found to have procoagulant activity identified as tissue factor. Under control conditions, tissue factor activity was found to be at low levels in marrow and blood populations compared to median activities 3- and 11- fold higher in populations from spleen and lymph node, and 33- and 45- fold higher in thymus and alveolar populations. By contrast to respective controls, significantly increased amounts of tissue factor (35-, 15-, and 12-fold at median levels) were found in marrow, blood, and spleen populations from endotoxemic animals. The types of leukocytes in these latter three populations were morphologically and histochemically indistinguishable from respective controls, indicating that endotoxin induced increases of activity in cells with relatively low amounts under control conditions. Activity did not change significantly in lymph node, thymus, or alveolar populations after endotoxemia. These studies show that tissue factor is present in a range of leukocyte populations not previously reported to have procoagulant activity. In addition, the finding of widespread gains of tissue factor in the marrow-blood-spleen pool due to endotoxemia provides new evidence supporting the importance of leukocyte procoagulants in Shwartzman-like reactions.  相似文献   
144.
ABSTRACT

Background

. Oral administration of bovine antibodies active against enterotoxigenic Escherichia coli (ETEC) have demonstrated safety and efficacy against diarrhea in human challenge trials. The efficacy of bovine serum immunoglobulins (BSIgG) against recombinant colonization factor CS6 or whole cell ETEC strain B7A was assessed against challenge with the CS6-expressing B7A.  相似文献   
145.
Abstract The efficacy of mask-applied continuous positive airway pressure (CPAP) in the treatment of patients with acute severe exacerbations of chronic obstructive pulmonary disease (COPD) was examined. Ten patients with severe exacerbation of COPD who had deteriorated during conventional therapy were treated with face-mask delivered CPAP (+5 cmH2 O; Downs Vital signs Inc., New Jersey, USA) instead of tracheal intubation and mechanical ventilation. The patients that were selected required mental alertness, intact upper airway reflexes, the clinical signs of dynamic hyperinflation and a positive end-expiratory pressure auto-(PEEP) manifested as expiratory wheeze and grunting. Nine out of 10 patients responded promptly to mask-CPAP with less distress, better oxygenation, lower respiratory and pulse rates. There was no significant change in arterial carbon dioxide tension with mask-CPAP treatment. One patient deteriorated on mask-CPAP and required intubation and mechanical ventilation. Three patients died (none of these patients died during the acute period of exacerbation). It was concluded that Mask-CPAP may be an alternative to mechanical ventilation in the treatment of selected patients with severe hypercapnic exacerbations of COPD.  相似文献   
146.

Background  

Burkholderia pseudomallei are the causative agent of melioidosis. Increasing resistance of the disease to antibiotics is a severe problem in treatment regime and has led to intensification of the search for new drugs. Antimicrobial peptides are the most ubiquitous in nature as part of the innate immune system and host defense mechanism.  相似文献   
147.
148.
Dixon AE  Yeh F  Welty TK  Rhoades ER  Lee ET  Howard BV  Enright PL 《Chest》2007,131(5):1323-1330
BACKGROUND: Despite growing recognition that asthma is an important cause of morbidity among American Indians, there has been no systematic study of this disease in older adults who are likely to be at high risk of complications related to asthma. Characterization of the impact of asthma among American Indian adults is necessary in order to design appropriate clinical and preventive measures. METHODS: A sample of participants in the third examination of the Strong Heart Study, a multicenter, population-based, prospective study of cardiovascular disease in American Indians, completed a standardized respiratory questionnaire, performed spirometry, and underwent allergen skin testing. Participants were > or = 50 years old. RESULTS: Of 3,197 participants in the third examination, 6.3% had physician-diagnosed asthma and 4.3% had probable asthma. Women had a higher prevalence of physician-diagnosed asthma than men (8.2% vs 3.2%). Of the 435 participants reported in the asthma substudy, morbidity related to asthma was high: among those with physician-diagnosed asthma: 97% reported trouble breathing and 52% had severe persistent disease. The mean FEV(1) in those with physician-diagnosed asthma was 61.3% of predicted, and 67.2% reported a history of emergency department visits and/or hospitalizations in the last year, yet only 3% were receiving regular inhaled corticosteroids. CONCLUSIONS: The prevalence of asthma among older American Indians residing in three separate geographic areas of the United States was similar to rates in other ethnic groups. Asthma was associated with low lung function, significant morbidity and health-care utilization, yet medications for pulmonary disease were underutilized by this population.  相似文献   
149.
OBJECTIVES: To describe longitudinal changes in the prevalence of major cardiovascular disease (CVD) risk factors in aging American Indians. DESIGN: Population-based ongoing epidemiological study. SETTING: The Strong Heart Study is a study of CVD and its risk factors. Standardized examinations were repeated in 1993 to 1995 and again in 1997 to 1999. PARTICIPANTS: A diverse cohort of 4,549 American Indians aged 45 to 74 at the initial examinations in 1989 to 1991. MEASUREMENTS: Changes in the prevalence of hypertension, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), current smoking, and type 2 diabetes mellitus. RESULTS: The prevalence of hypertension rose rapidly and steadily with aging. A nonsignificant decrease in LDL-C was seen in men, and men and women initially had rapid increases in the prevalence of low HDL-C. The prevalence of smoking decreased, but the prevalence of diabetes mellitus continued to rise for men and women. CONCLUSION: Overall, unfavorable changes in CVD risk factors were seen in the aging participants and will likely be reflected in worsening morbidity and mortality.  相似文献   
150.
We examined the effect of an outpatient office-based diet and exercise counseling program on weight loss and lipid levels with an onsite dietitian who sees patients at the same visit with the physician and is fully reimbursable. Eighty overweight or obese patients (average age 55 +/- 12 years, baseline body mass index 30.1 +/- 6.4 kg/m(2)) with > or =1 cardiovascular risk factor (86%) or coronary heart disease (14%) were counseled to exercise 30 minutes/day and eat a modified Dietary Approaches to Stop Hypertension (DASH) diet (saturated fat <7%, polyunsaturated fat to 10%, monounsaturated fat to 18%, low in glycemic index and sodium and high in fiber, low-fat dairy products, fruits, and vegetables). Weight, body mass index, lipid levels, and blood pressure were measured at 1 concurrent follow-up visit with the dietitian and physician and > or =1 additional follow-up with the physician. Maximum weight lost was an average of 5.6% (10.8 lb) at a mean follow-up of 1.75 years. Sixty-four (81%) of these patients maintained significant weight loss (average weight loss 5.3%) at a mean follow-up of 2.6 years. Average decrease in low-density lipoprotein cholesterol was 9.3%, average decrease in triglycerides was 34%, and average increase in high-density lipoprotein cholesterol was 9.6%. Systolic blood pressure was lowered from 129 to 126 mm Hg (p = 0.21) and diastolic blood pressure from 79 to 75 mm Hg (p = 0.003). In conclusion, having a dietitian counsel patients concurrently with a physician in the outpatient setting is effective in achieving and maintaining weight loss and is fully reimbursable.  相似文献   
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