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11.
Background:With the emergence of lifestyle diseases in epidemic proportions, obstructive sleep apnea (OSA) is being increasingly recognized in less developed countries as well.Aim:We sought to study the demographic, clinical, and polysomnographic (PSG) predictors of OSA severity in a cohort of South Indian patients.Results:There were 152 (119 males and 33 females) subjects with a mean age of 53.8 years and body mass index (BMI) of 29.31. Mean AHI was 36.2/h (range: 5.1-110) and 66 subjects had severe OSA. Around 12% had the presenting complaint as insomnia, mainly of sleep maintenance. Of the subjects, 35% had witnessed apneas and 67% had excessive daytime sleepiness (EDS); 40% of patients had ≥2 risk factors. PSG parameters showed short sleep onset latency with a high arousal index. Mean apnea duration was 24.92 s. We found that age >55 years, BMI >25 kg/m2, witnessed apneas, EDS, hypertension, dyslipidemia, reduced slow wave sleep duration, mean apnea duration >20 s, and desaturation index >10/h correlated well with OSA severity while the arousal index, sleep latency and efficiency, and exposure to smoking and alcohol showed no association.Conclusions:Older subjects with witnessed apneas are likely to have more severe OSA. Even though overall sleep architecture was similar between the groups, severe OSA had shorter slow wave sleep, longer apneas, and higher nocturnal hypoxemia.  相似文献   
12.
BACKGROUND: There are known racial disparities in renal graft survival. Data are lacking comparing associations of race/ethnicity and socioeconomic status with graft failure and functional status after transplantation. Our goal was to test if African-American and Hispanic race/ethnicity and poverty are associated with worse outcomes following renal transplantation. METHODS: We performed a retrospective cohort study using a nationwide registry (United Network for Organ Sharing). We studied 4,471 adults who received renal transplants in 1990. Outcomes were graft failure and functional status over 10 years. RESULTS: Cumulative incidence of graft failure was higher among African-Americans and Hispanics than whites (77% vs. 64% vs. 60 %; P<0.001) and among transplant recipients living in the poorest areas (70% vs. 58% in the richest; P<0.001). African-American and Hispanic race/ethnicity were independently predictive of graft failure (RR 1.8, 95% CI 1.6-1.9; RR 1.3, 95% CI 1.2-1.6, respectively) in multivariate analyses but poverty status was not (RR 1.0, 95% CI 0.9-1.1). Days with impaired functional status were higher for African-Americans compared to whites (RR 1.6, 95% CI 1.3-1.9) but not independent of poverty. Poverty was independently associated with impaired functional status (RR 1.3, 95% CI 1.0-1.6). CONCLUSIONS: African-Americans and Hispanics had higher rates of graft failure compared to whites after adjustment for poverty and other covariates whereas poverty, but not race/ethnicity, was related to functional status following renal transplantation. National datasets should include individual-level measures of socioeconomic status in order to improve evaluation of social and environmental causes of disparities in renal transplant outcomes.  相似文献   
13.
The findings of diffuse tubular injury with abundant tubular calcium phosphate deposits on renal biopsy are referred to as nephrocalcinosis, a condition typically associated with hypercalcemia. During the period from 2000 to 2004, 31 cases of nephrocalcinosis were identified among the 7349 native renal biopsies processed at Columbia University. Among the 31 patients, 21 presented with acute renal failure (ARF), were normocalcemic, and had a history of recent colonoscopy preceded by bowel cleansing with oral sodium phosphate solution (OSPS) or Visicol. Because the precipitant was OSPS rather than hypercalcemia, these cases are best termed acute phosphate nephropathy. The cohort of 21 patients with APhN was predominantly female (81.0%) and white (81.0%), with a mean age of 64.0 yr. Sixteen of the 21 patients had a history of hypertension, 14 (87.5%) of whom were receiving an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker. The mean baseline serum creatinine was 1.0 mg/dl, available within 4 mo of colonoscopy in 19 (90.5%) patients. Patients presented with ARF and a mean creatinine of 3.9 mg/dl at a median of 1 mo after colonoscopy. In a few patients, ARF was discovered within 3 d of colonoscopy, at which time hyperphosphatemia was documented. Patients had minimal proteinuria, normocalcemia, and bland urinary sediment. At follow-up (mean 16.7 mo), four patients had gone on to require permanent hemodialysis. The remaining 17 patients all have developed chronic renal insufficiency (mean serum creatinine, 2.4 mg/dl). Acute phosphate nephropathy is an underrecognized cause of acute and chronic renal failure. Potential etiologic factors include inadequate hydration (while receiving OSPS), increased patient age, a history of hypertension, and concurrent use of an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker.  相似文献   
14.
We examined whether challenging upright stance influences the execution of a grasping task. Participants reached to grasp a small sphere while standing either on a stable surface or on foam. Before reaching for the sphere, participants exhibited more body sway and greater fluctuations in the centre of pressure when standing on foam. While reaching for the sphere, the overall body posture changed less when standing on foam than when standing on the stable surface. The digits’ and wrist's movements towards the sphere were no different when standing on foam than when standing on the stable surface. Presumably, the redundancy in the way movements can be performed is exploited to choose the most suitable changes in joint angles to achieve the desired movements of the digits under the prevailing conditions.  相似文献   
15.
The authors describe a technique for construction of a continent catheterizable stoma from distal defunctionalized colon in a patient with imperforate anus, urethral atresia, and sacral agenesis.  相似文献   
16.
Background/Purpose: Endothelin is a potent mediator of the cardiovascular and renal systems. Studies have found that endothelin has an important role in regulating cardiac function and renal perfusion in neonates who are suffering from endotoxic shock. The authors believe that blockade of the endothelin response during endotoxemia will have a beneficial effect on neonatal cardiac and renal functions. In this study the authors have examined the effects of tezosentan, a dual endothelin-receptor antagonist, on the cardiovascular and renal systems of neonatal piglets during endotoxemia. Methods: Thirteen piglets were subjected to endotoxic shock and divided into a fluid-therapy group that received 0.9% normal saline and a group that received tezosentan (1 mg/kg/h). Mean arterial pressure (MAP), heart rate (HR), and glomerular filtration rate (GFR) were plotted at baseline, 1, 2, and 3 hours. Cardiac index (CI), renal blood flow (RBF), systemic vascular resistance (SVR), and renal vascular resistance (RVR) were obtained at baseline, 1, and 3 hours after baseline. Results: (P [lt ] .05 for 3 hours versus baseline and tezosentan versus fluid). Although fluid therapy in endotoxemia had no significant effect on MAP and RVR, it significantly increased HR (139 [plusmn] 17 to 246 [plusmn] 17 beats/min) and SVR (0.08 [plusmn] 0.05 to 0.33 [plusmn] 0.09 mm Hg/mL/min) and decreased CI (407 [plusmn] 208 to 98 [plusmn] 13 mL/min/kg), RBF (1.84 [plusmn] 0.38 to 0.97 [plusmn] 0.34 mL/min/kg kidney), and GFR (0.20 [plusmn] 0.05 to 0.11 [plusmn] 0.04 mL/min/kg) at 3 hours. The use of tezosentan also significantly increased HR (130 [plusmn] 14 to 220 [plusmn] 31 beats/min), but unlike in the fluid therapy group, there was a significant fall in MAP (77 [plusmn] 10 to 54 [plusmn] 9 mm Hg) and RVR (1.92 [plusmn] 0.44 to 1.77 [plusmn] 0.64 mm Hg/mL/min) and a less severe decrease in CI (482 [plusmn] 188 to 176 [plusmn] 67 mL/min/kg) at 3 hours. SVR, RBF, and GFR were maintained. Conclusions: Endotoxic shock affected cardiac and renal functions in both treatment groups. Fluid therapy alone could not prevent a statistically significant fall in CI, RBF, and GFR or prevent the increase in HR and SVR. Endothelin antagonism with tezosentan resulted in a statistically significant fall in MAP and RVR from baseline, not seen in the fluid-therapy group. CI and RBF were significantly higher, and MAP, SVR, and RVR were significantly lower when compared with the fluid-therapy group at 3 hours. GFR also was maintained at baseline with tezosentan. During endotoxemia, endothelin antagonism maintained renal and cardiac functions better than with fluid therapy alone.  相似文献   
17.
Background Despite improving surgical techniques, treatment of heart valve disease in children remains controversial. Somatic growth and adequate anticoagulation are of concern when children undergo valve replacement. We conducted this study to evaluate the performance of valves in this age group. Methods 42 children under the age of 13 years who underwent valve replacement were included in this study. Totally, 50 valves were implanted in 42 patients: 48 were mechanical prostheses, two were bioprosthetic both in pulmonary position. 37 (74%) valves were implanted in mitral position, 10 (20%) in aortic position, 1 (2%) in tricuspid position and 2 (4%) in pulmonary position. Preoperatively, 14 (33,3%) patients were in New York Heart Association (NYHA) class IV, while 27 (64.2%) were in NYHA class III. Results There were 2 (4.7%) hospital deaths and 2 (4.7%) late deaths while 2 (4.7%) patients were lost to follow up. The mean follow up period was 9.4 yrs. 35 (83.3%) patients are in NYHA Class I and free of all medications except warfarin. 3 (7.1%) patients have undergone 5 successful pregnancies. The median INR was 2.23. Major thrombo-embolic episode occurred in 1 (2.3%) patient. Conclusions In view of the problems of sizing, anticoagulation and need for re-operation at an early age, there is a reluctance to replace valves in children. This study shows that despite these problems, valve replacement can be undertaken safely and successfully in children, when repair has failed or not technically feasible.  相似文献   
18.
BACKGROUND: Surgical resection of malignant pleural mesothelioma is reported to have up to an 80% rate of local recurrence. We performed a phase II trial of high-dose hemithoracic radiation after complete resection to determine feasibility and to estimate rates of local recurrence and survival. METHODS: Patients were eligible if they had a resectable tumor, as determined by computed tomographic scanning, and adequate cardiopulmonary function for extrapleural pneumonectomy or pleurectomy/decortication. After complete resection, patients received hemithoracic radiation (54 Gy) and then were followed up with serial computed tomographic scanning. RESULTS: From 1995 to 1998, 88 patients (73 men and 15 women; median age, 62.5 years) were entered into the study. The operations performed included 62 extrapleural pneumonectomies (70%) and 5 pleurectomies/decortications; procedures for exploration only were performed in 21 patients. Seven (7.9%) patients died postoperatively. Adjuvant radiation administered to 57 patients (54 undergoing extrapleural pneumonectomy and 3 undergoing pleurectomy/decortication) at a median dose of 54 Gy was well tolerated (grade 0-2 fatigue, esophagitis), except for one late esophageal fistula. The median survival was 33.8 months for stage I and II tumors but only 10 months for stage III and IV tumors (P =.04). For the patients undergoing extrapleural pneumonectomy, the sites of recurrence were locoregional in 2, locoregional and distant in 5, and distant only in 30. CONCLUSION: Hemithoracic radiation after complete surgical resection at a dose not previously reported is feasible. This approach dramatically reduces local recurrence and is associated with prolonged survival for early-stage tumors. Stage III disease has a high risk of early distant relapse and should be considered for trials of systemic therapy added to this regimen of resection and radiation.  相似文献   
19.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Understanding the chemical basis of rhizobacterial-plant interaction provides immense opportunities for the...  相似文献   
20.
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