首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   28104篇
  免费   1557篇
  国内免费   155篇
耳鼻咽喉   93篇
儿科学   1616篇
妇产科学   666篇
基础医学   2301篇
口腔科学   125篇
临床医学   3004篇
内科学   8185篇
皮肤病学   474篇
神经病学   2095篇
特种医学   244篇
外科学   3123篇
综合类   781篇
现状与发展   1篇
一般理论   6篇
预防医学   2592篇
眼科学   979篇
药学   1178篇
  2篇
中国医学   70篇
肿瘤学   2281篇
  2024年   100篇
  2023年   310篇
  2022年   259篇
  2021年   381篇
  2020年   363篇
  2019年   130篇
  2018年   509篇
  2017年   526篇
  2016年   578篇
  2015年   561篇
  2014年   474篇
  2013年   744篇
  2012年   2122篇
  2011年   2481篇
  2010年   845篇
  2009年   830篇
  2008年   2547篇
  2007年   2428篇
  2006年   2115篇
  2005年   2176篇
  2004年   2220篇
  2003年   2227篇
  2002年   1760篇
  2001年   1351篇
  2000年   326篇
  1999年   170篇
  1998年   233篇
  1997年   143篇
  1996年   107篇
  1995年   106篇
  1994年   89篇
  1993年   49篇
  1992年   54篇
  1991年   48篇
  1990年   47篇
  1989年   47篇
  1988年   42篇
  1987年   43篇
  1986年   37篇
  1985年   28篇
  1984年   30篇
  1983年   12篇
  1982年   20篇
  1981年   19篇
  1980年   15篇
  1979年   15篇
  1978年   13篇
  1974年   9篇
  1970年   9篇
  1969年   11篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
12.

Background

(Buccalin ®) is a Bacterial Lysates (BL) that belongs to a family of immune-stimulators, developed more than 30 years ago and it still has a role in the prophylaxis of Recurrent Respiratory Tract Infections (RRTI). However, original studies were conducted with an approach that does not seem to be aligned with the present methodologies. In addition, concomitant therapies substantially improved in the last decades. These two reasons strongly suggested to update our knowledge on the capacity of this bacterial lysate (Buccalin ®) to reduce the number of days with infectious episodes in patients with RRTI.

Methods

A double blind, placebo-controlled, randomized, multicentre study was programmed (EudraCT code: 2011-005187-25). The reduction of the number of days with infectious episodes (IE) was the primary endpoint. Secondary endpoints were the number of IE, the use of concomitant drugs, the efficacy on signs and symptoms of RRTI and the safety of the drug. Patients were treated according to the registered schedule and were followed up for a period of 6 months.

Results

From a cohort of 188 patients eligible for the study, 90 were included in the active group and 88 in the placebo group. The study was completed in 170 patients. A significant reduction of the number of days with IE was observed (6.57 days in the active group and 7.47 in the placebo group). Secondary endpoints were only partially achieved. No virtual adverse events related to the treatment were recorded.

Conclusion

The administration of bacterial lysate (Buccalin ®) in patients with RRTI had the capacity to significantly reduce the number of days with IE in a multicentre, randomized, placebo controlled, clinical study. The treatment was safe. Of note, all patients were free to be treated with the best concomitant therapies. In these conditions, the positive results observed demonstrated that this bacterial lysate has maintained its capacity of reducing the days with infections in patients with RRTI, also in association to the concomitant therapies available nowadays.
  相似文献   
13.
14.
大鼠应激性溃疡发病机制及其防治方法的研究   总被引:8,自引:2,他引:8  
为进一步了解应激性溃疡的发病机制,寻找更有效的治疗方法。以冷束缚法制成大鼠应激性溃疡动物模型。将其分成对照组、治疗A组(西米替丁组)、治疗B组(东莨菪碱组)和治疗C组(西米替丁+东莨菪碱组),通过溃疡指教、光镜与电镜观察各组病理组织学变化。结果:治疗C组防治效果优于治疗A组及B组。作者认为:在应激状态下,胃粘膜局部血循环障碍与胃内pH过低是导致损伤的重要始动因素;综合使用抑酸与促进血循环的防治方法,其效果明显优于单纯抑酸方法。  相似文献   
15.

Background

Combined treatment with cyclosporine microemulsion preconcentrate (CyA MEPC) and steroids has been widely used for idiopathic membranous nephropathy (IMN) associated with steroid-resistant nephrotic syndrome (SRNS). Recent studies have shown that once-a-day and preprandial administration of CyA MEPC is more advantageous than the conventional twice-a-day administration in achieving the target blood CyA concentration at 2 h post dose (C2). We designed a randomized trial to compare these administrations.

Methods

IMN patients with SRNS (age 16–75 years) were divided prospectively and randomly into 2 groups. In group 1 (n = 23), 2–3 mg/kg body weight (BW) CyA MEPC was given orally once a day before breakfast. In group 2 (n = 25), 1.5 mg/kg BW CyA MEPC was given twice a day before meals. CyA + prednisolone was continued for 48 weeks.

Results

Group 1 showed a significantly higher cumulative complete remission (CR) rate (p = 0.0282), but not when incomplete remission 1 (ICR1; urine protein 0.3–1.0 g/day) was added (p = 0.314). Because a C2 of 600 ng/mL was determined as the best cut-off point, groups 1 and 2 were further divided into subgroups A (C2 ≥600 ng/mL) and B (C2 <600 ng/mL). Groups 1A and 2A revealed significantly higher cumulative remission (CR + ICR1) (p = 0.0069) and CR-alone (p = 0.0028) rates. On the other hand, 3 patients with high CyA levels (C2 >900 ng/mL) in Group 1A were withdrawn from the study because of complications.

Conclusion

CyA + prednisolone treatment is effective for IMN with associated SRNS at a C2 of ≥600 ng/mL. To achieve remission, preprandial once-a-day administration of CyA at 2–3 mg/kg BW may be the most appropriate option. However, we should adjust the dosage of CyA by therapeutic drug monitoring to avoid complications.  相似文献   
16.

Background

There is increasing focus on the problems involved in the transition and transfer of young adult patients from paediatric to adult renal units. This situation was addressed by the 2011 International Pediatric Nephrology Association/International Society of Nephrology (IPNA/ISN) Consensus Statement on transition.

Methods

We performed a survey of transition practices of 15 paediatric nephrology units across Europe 2 years after publication of the consensus statement.

Results

Two thirds of units were aware of the guidelines, and one third had integrated them into their transition practice. Forty-seven per cent of units transfer five or fewer patients with chronic kidney disease (CKD) stage 5 per year to a median of five adult centres, with higher numbers of CKD stages 2–4 patients. Seventy-three per cent of units were required by the hospital or government to transfer patients by a certain age. Eighty per cent of units commenced transition planning after the patient turned 15 years of age and usually within 1–2 years of the compulsory transfer age. Forty-seven per cent of units used a transition or transfer clinic. Prominent barriers to effective transition were patient and parent attachment to the paediatric unit and difficulty in allowing the young person to perform self-care.

Conclusions

Whereas awareness of the consensus statement is suboptimal, it has had some impact on practice. Adult nephrologists receive transferred patients infrequently, and the process of transition is introduced too late by paediatricians. Government- and hospital-driven age-based transfer policies distract focus from the achievement of competencies in self care. Variable use of transition clinics, written patient information and support groups is probably due to economic and human-resource limitations. The consensus statement provides a standard for evolving and evaluating transition policies jointly agreed upon by paediatric and adult units.  相似文献   
17.
This study evaluated the safety and efficacy of a sirolimus, corticosteroid, and cyclosporine reduction regimen in an open‐label, 12‐month trial of 420 de novo renal allograft recipients at 49 European transplant centers. One month post‐transplantation, 357 patients were randomized to receive standard‐dose cyclosporine (sCsA, n = 179) or reduced‐dose cyclosporine (rCsA, n = 178). All patients also received sirolimus and corticosteroids. The primary end points were the rate of biopsy‐confirmed acute rejection (BCAR) and renal function, as measured by serum creatinine. Baseline demographic and donor characteristics were similar between groups. BCAR rates at 12 months were not significantly different: 11.2% for rCsA patients and 16.2% for sCsA patients. Mean serum creatinine (±SEM) was significantly lower (1.75 ± 0.10 vs. 1.97 ± 0.07 mg/dl, < 0.001), and creatinine clearance (±SEM; Nankivell method) was significantly higher (57.8 ± 1.78 vs. 49.5 ± 2.46 ml/min, < 0.001) in patients receiving rCsA versus sCsA at 1 year, respectively. Patient and graft survival exceeded 98% in both groups. No significant differences in infection or malignancy were noted between groups. The rCsA with sirolimus and corticosteroid regimen resulted in excellent 12‐month patient and graft survival, a low incidence of BCAR, and improved renal function in renal allograft recipients. Sirolimus administered with rCsA and corticosteroids provided adequate immunosuppression while reducing the potential for the nephrotoxic effects of cyclosporine. These findings may help to improve long‐term renal allograft outcomes.  相似文献   
18.
19.
OBJECTIVE: To examine the acute glucose-lowering effects of aerobic exercise in children and adolescents with type 1 diabetes. RESEARCH DESIGN AND METHODS: Fifty children and adolescents with type 1 diabetes (ages 10 to <18 years) were studied during exercise. The 75-min exercise session consisted of four 15-min periods of walking on a treadmill to a target heart rate of 140 bpm and three 5-min rest periods. Blood glucose and plasma glucagon, cortisol, growth hormone, and norepinephrine concentrations were measured before, during, and after exercise. RESULTS: In most subjects (83%), plasma glucose concentration dropped at least 25% from baseline, and 15 (30%) subjects became hypoglycemic (< or = 60 mg/dl) or were treated for low glucose either during or immediately following the exercise session. The incidence of hypoglycemia and/or treatment for low glucose varied significantly by baseline glucose, occurring in 86 vs. 13 vs. 6% of subjects with baseline values <120, 120-180, and >180 mg/dl, respectively (P < 0.001). Exercise-induced increases in growth hormone and norepinephrine concentrations were marginally higher in subjects whose glucose dropped < or = 70 mg/dl. Treatment of hypoglycemia with 15 g of oral glucose resulted in only about a 20-mg/dl rise in glucose concentrations. CONCLUSIONS: In youth with type 1 diabetes, prolonged moderate aerobic exercise results in a consistent reduction in plasma glucose and the frequent occurrence of hypoglycemia when preexercise glucose concentrations are <120 mg/dl. Moreover, treatment with 15 g of oral glucose is often insufficient to reliably treat hypoglycemia during exercise in these youngsters.  相似文献   
20.
A growing number of Japanese patients are being treated with ICDs. Efforts are warranted to minimize the rates of ICD shocks that cause discomfort and anxiety. The circadian distribution of ICD discharges was investigated in 80 patients (57+/-10 years of age, 69 men) from ten Japanese medical centers. The underlying heart disease was ischemic in 27 versus nonischemic in 53 patients. All patients had refractory VT or VF, and received appropriate shocks confirmed by stored data retrieved from the memory of the ICD. In the analysis of 354 appropriate shocks delivered in the overall population, a morning peak in VT or VF episodes was observed. However, subgroup analyses of the circadian distribution of ICD shocks revealed that the morning peak in VT or VF episodes was confined to patients with ischemic heart disease and was blunted by treatment patients with beta-adrenergic blockers. The absence of a morning peak in appropriate ICD shocks among patients with nonischemic heart disease remains unexplained and was unrelated to the use of beta-adrenergic blockers. In conclusion, the circadian pattern of appropriate ICD discharges was related to the underlying heart disease. In patients with ischemic heart disease, recurrences of VT or VF peaked in the morning. In contrast, in patients without ischemic heart disease, the episodes of VT or VF were evenly distributed during waking hours. Beta-adrenergic blockers appeared to blunt the morning peak in VT or VF among patients with ischemic heart disease.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号