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41.
Background. The aim of this study was to evaluate the influence of oral vitamin E therapy on serum concentrations of several markers of micro-inflammation and cardiovascular disease in chronic hemodialysis (HD) patients. Methods. 29 HD patients were randomized into two groups: 15 patients were treated orally with 400mg of vitamin E daily for a period of five weeks, and 14 patients received no antioxidant supplementation. Before and after vitamin E therapy, serum concentrations of vitamin E (high-performance liquid chromatography), pregnancy-associated plasma protein-A (immunochemical – TRACE assay), C-reactive protein (nephelometry), intercellular adhesion molecule-1 (ELISA), and E-selectin (ELISA) were measured. HD patients were compared with 16 healthy controls. Results. Baseline serum concentrations of PAPP-A and CRP were significantly higher in HD patients than in healthy controls (PAPP-A: 26.23±11.94 vs. 11.41±1.94 mIU/L, p<0.001; CRP: 5.20±3.50 vs. 3.40±3.80 mg/L, p<0.05). After five weeks of oral vitamin E intake, serum PAPP-A, CRP, ICAM-1, and E-selectin concentrations remained unchanged in both groups of HD patients. Conclusion. Chronic micro-inflammation in HD patients is documented by the elevation of CRP and PAPP-A. A daily oral dose of 400 mg of vitamin E does not seem to be able to reduce enhanced oxidative stress and micro-inflammation in chronic HD patients.  相似文献   
42.
In a systematic search for peroxisome proliferator-activated receptor-gamma (PPAR-gamma) target genes, we identified S3-12 and perilipin as novel direct PPAR-gamma target genes. Together with adipophilin and tail-interacting protein of 47 kDa, these genes are lipid droplet-associating proteins with distinct expression pattern but overlapping expression in adipose tissue. The expression of S3-12 and perilipin is tightly correlated to the expression and activation of PPAR-gamma in adipocytes, and promoter characterization revealed that the S3-12 and the perilipin promoters contain three and one evolutionarily conserved PPAR response elements, respectively. We furthermore demonstrate that the expression of S3-12 and perilipin is reduced in obese compared with lean Zucker rats, whereas the expression of adipophilin is increased. Others have shown that perilipin is an essential factor in the hormonal regulation of lipolysis of stored triglycerides within adipose tissue. The direct regulation of perilipin and S3-12 by PPAR-gamma therefore is likely to be an important mediator of the in vivo effects of prolonged treatment with PPAR-gamma activators: insulin sensitization, fatty acid trapping in adipose tissue, reduced basal adipose lipolysis, and weight gain.  相似文献   
43.
The objective of this study was to characterize, and determine the significance of, pulmonary activity on labelled leukocyte images. This retrospective review included 137 immunocompetent patients who had undergone 111In labelled autologous leukocyte chest imaging and chest X-ray within 7 days. Pulmonary activity was classified as normal, focally increased, or diffusely increased. Images were correlated with chest X-rays and final diagnoses. One hundred and twelve patients (82%) had normal pulmonary activity. Seventy-six had normal chest X-rays; none had pulmonary infection. Thirty-six patients had chest X-ray abnormalities; only one had pulmonary infection. Twenty-five patients had abnormal pulmonary activity. In 13 patients it was segmental or lobar in distribution. The chest X-ray was abnormal in 12: pneumonia (11) and cystic fibrosis (one). The chest X-ray was normal in one patient with pneumonia. Two patients with non-segmental pulmonary activity did not have pulmonary infection. The chest X-ray was abnormal in one (pulmonary edema) and normal in one (sepsis). Ten patients had diffuse pulmonary activity. Chest X-ray was abnormal in two patients: adult respiratory distress syndrome (ARDS) (one) and drug toxicity (one). No patient with diffuse pulmonary activity had pulmonary infection. In summary, negative labelled leukocyte imaging excludes pulmonary infection with a high degree of certainty (the negative predictive value was 99% in this series), and can exclude pneumonia as the cause of a chest X-ray abnormality. Focal pulmonary activity strongly suggests pneumonia, while diffuse pulmonary activity is unlikely to indicate infection.  相似文献   
44.
The records of all patients with familial polyposis coli and ulcerative colitis operated at The Mount Sinai Hospital were reviewed to determine the proportion of patients with cancer at the time of colon resection. Sixty-nine patients with familial polyposis coli undergoing operation between 1947 and 1983 were identified and 25 (36 percent) were found to have cancer. In the group with ulcerative colitis, 548 patients had surgical treatment between 1957 and 1983 and 65 (12 percent) had colonic cancer. There was a significant decrease in the proportion of patients with familial polyposis coli having cancer at the time of colon resection from 50 percent before 1968 to 20 percent since 1978. This change in cancer incidence was found to correlate with a decrease in the mean age at operation from 40 to 25 years. In the group with ulcerative colitis, the mean age at operation has remained essentially unchanged at 36 years. The proportion of patients with ulcerative colitis having cancer at the time of colon resection has remained constant throughout this study. Progression to carcinoma is still a significant concern in both familial polyposis coli and ulcerative colitis. Although removal of the colon and rectum prevents cancer development, patient selection and timing of the operation remain a difficult problem.  相似文献   
45.
Abstract Background and aim: Isolated thoracic aortitis (ITA) is a newly‐defined pathological entity with a still‐unknown etiopathology and with some potential relationship to IgG4‐related systemic disease. We investigated patients on whom the ascending aorta was operated to identify the clinical and histopathological features of ITA and its relationship to IgG4‐related systemic disease. Methods: Two hundred fifty‐one patients underwent replacement of the ascending aorta. Retrospective review of all histological reports was done to identify noninfectious aortitis. Immunohistochemical analysis of resected specimens was performed in all cases. Results: We found 11 (4.4%) patients with noninfectious aortitis aged 52 to 79 years; nine of the patients were female. All patients underwent ascending aorta replacement. The 30‐day mortality was 0. During the follow‐up period (median 12 months) four patients died (two of them because of progression of aortic disease). None of the seven living patients developed any IgG4‐related diseases, and all had normal serum levels of IgG and IgG4. Conclusions: Surgical treatment of ITA has acceptable short‐ and mid‐term results. Because follow‐up serum levels of IgG and IgG4 were normal in survivors, postoperative corticosteroid therapy may not be indicated in patients in the absence of active vasculitis.  相似文献   
46.
47.
BACKGROUND: The long-term benefits of angioplasty are limited by the occurrence of restenosis. Drug-eluting stents with a projected restenosis rate of close to 0% are soon to become available. The short- and long-term consequences of this advance to the cardiac surgical volume remain unclear. METHODS: A total of 196 consecutive coronary angiograms and medical records of patients referred for coronary bypass surgery were reviewed. Considering the hypothetical premise of having drug-eluting stents with a near zero restenosis rate, we reviewed each case to determine if surgical revascularization was still the preferred option for revascularization. RESULTS: The mean age was 60 (+/-10.6) years. Seventy-two percent of patients were male. Considering the availability of drug-eluting stents 154 (79%) would still have been sent to surgery, representing a 21% decrease in the number of surgical revascularizations. Angiographic characteristics predicting coronary bypass revascularization were the presence of chronic total occlusion (odds ratio [OR]: 9.1; confidence interval [CI]: 2.1 to 39), left main coronary artery stenosis (OR: 9.6; CI: 1.27 to 73), and need for valvular surgery (OR: 7.38; CI: 1.3 to 157). The most common predictors of a change in clinical management from surgical to percutaneous revascularization if drug-eluting stents were available were diffuse coronary narrowing (OR: 15.78), restenotic lesions (OR: 27.86), and small coronary arteries (OR: 26). CONCLUSIONS: Drug-eluting stents may have a significant impact on cardiac surgery volume (approximately a 21% decrease in our center). It may also direct patients with small vessels, diffuse narrowing, or restenotic lesions and diabetic patients to percutaneous therapy.  相似文献   
48.
A 66-year-old male presented with rhabdomyosarcoma of the right kidney with inferior vena cava tumor thrombus and with tumor emboli to right pulmonary artery and two large fragments of tumor thrombus free floating in the right atrium. The patient underwent right radical nephrectomy and thrombectomy of the right atrium and pulmonary artery. He was discharged on postoperative day 13. To our knowledge this is the first case of large tumor embolism to the right atrium and pulmonary artery from renal rhabdomyosarcoma reported in the literature.  相似文献   
49.
Competitive athletics is often associated with moderate left ventricular (LV) hypertrophy, and it has been hypothesized that training mode and type of exercise modulates long-term cardiac adaptation. The purpose of the study was to compare cardiac structure and function among athletes of various sports and sedentary controls. Standard transthoracic two-dimensional M-mode and Doppler echocardiography was performed at rest in Caucasian male canoe/kayak paddlers (n = 9), long distance runners (LDR, n = 18), middle distance runners (MDR, n = 17), basketball players (BP, n = 31), road cyclists (n = 8), swimmers (n = 10), strength/power athletes (n = 9) of similar age (range, 15 to 31 yrs), training experience (4 to 9 years), and age-matched healthy male sedentary controls (n = 15). Absolute interventricular septum (IVS) thickness and LV wall thickness, but not LV diameter, were greater in athletes than sedentary controls. Left ventricular mass of all athletes but relative wall thickness of only BP, swimmers, cyclists, and strength/power athletes were higher as compared with controls (p < 0.05). Among athletes, smaller IVS thickness was observed in MDR than BP, cyclists, swimmers or strength/power athletes, while LDR had higher body size-adjusted LV diameter as compared to BP, cyclists and strength/power athletes. In conclusion, relative LV diameter was increased in long distance runners as compared with basketball players, cyclists, and strength/power athletes. Basketball, road cycling, strength/power, and swimming training were associated with increased LV concentricity as compared with paddling or distance running.

Key points

  • The type of cardiac hypertrophy seems to be only moderately exercise-specific.
  • Long-distance runners develop larger left ventricular dilation as compared with basketball players, cyclists, and strength/power athletes.
  • Myocardial wall thickening is triggered by different sporting activities that involve large muscle groups.
Key words: Myocardial hypertrophy, left ventricle, echocardiography, athlete  相似文献   
50.
OBJECTIVE: To evaluate the outcome of aggressive conservative therapy in patients with esophageal perforation. SUMMARY BACKGROUND DATA: The treatment of esophageal perforation remains controversial with a bias toward early primary repair, resection, and/or proximal diversion. This review evaluates an alternate approach with a bias toward aggressive drainage of fluid collections and frequent CT and gastographin UGI examinations to evaluate progress. METHODS: From 1992 to 2004, 47 patients with esophageal perforation (10 proximal, 37 thoracic) were treated (18 patients early [<24 hours], 29 late). There were 31 male and 16 females (ages 18-90 years). The etiology was iatrogenic (25), spontaneous (14), trauma (3), dissecting thoracic aneurysm (3), and 1 each following a Stretta procedure and Blakemore tube placement. RESULTS: Six of 10 cervical perforations underwent surgery (3 primary repair, 3 abscess drainage). Nine of 10 perforations healed at discharge. In 37 thoracic perforations, 2 underwent primary repair (1 iatrogenic, 1 spontaneous) and 4 underwent limited thoracotomy. Thirty-4 patients (4 cervical, 28 thoracic) underwent nonoperative treatment. Thirteen of the 14 patients with spontaneous perforation (thoracic) underwent initial nonoperative care. Overall mortality was 4.2% (2 of 47 patients). These deaths represent 2 of 37 thoracic perforations (5.4%). There were no deaths in the 34 patients treated nonoperatively. Esophageal healing occurred in 43 of 45 surviving patients (96%). Subsequent operations included colon interposition in 2, esophagectomy for malignancy in 3, and esophagectomy for benign stricture in 2. CONCLUSIONS: Aggressive treatment of sepsis and control of esophageal leaks leak lowers mortality and morbidity, allow esophageal healing, and avoid major surgery in most patients.  相似文献   
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