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   9423篇
  免费   531篇
  国内免费   49篇
耳鼻咽喉   53篇
儿科学   300篇
妇产科学   257篇
基础医学   1050篇
口腔科学   443篇
临床医学   1023篇
内科学   1807篇
皮肤病学   92篇
神经病学   849篇
特种医学   451篇
外科学   1266篇
综合类   378篇
一般理论   11篇
预防医学   953篇
眼科学   177篇
药学   494篇
  1篇
中国医学   3篇
肿瘤学   395篇
  2022年   57篇
  2021年   139篇
  2020年   73篇
  2019年   128篇
  2018年   135篇
  2017年   117篇
  2016年   121篇
  2015年   145篇
  2014年   189篇
  2013年   308篇
  2012年   415篇
  2011年   438篇
  2010年   249篇
  2009年   222篇
  2008年   376篇
  2007年   443篇
  2006年   402篇
  2005年   391篇
  2004年   367篇
  2003年   334篇
  2002年   350篇
  2001年   282篇
  2000年   284篇
  1999年   262篇
  1998年   133篇
  1997年   133篇
  1996年   126篇
  1995年   107篇
  1994年   101篇
  1993年   94篇
  1992年   221篇
  1991年   225篇
  1990年   237篇
  1989年   198篇
  1988年   226篇
  1987年   225篇
  1986年   196篇
  1985年   201篇
  1984年   100篇
  1983年   103篇
  1982年   75篇
  1981年   72篇
  1980年   66篇
  1979年   83篇
  1978年   83篇
  1977年   61篇
  1975年   50篇
  1974年   59篇
  1972年   59篇
  1971年   65篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Examination of the causes of late mortality in multiple trauma patients reveals that as much as 78% of all deaths may be attributed to septic complications, suggesting the value of understanding the prevention and treatment of traumatic sepsis. In penetrating trauma, the protective features of the skin are eliminated, and systemic mechanisms of host defense are compromised. These changes in the host defense mechanism and the risk of infection influence the choice and technical features of wound closure and the use of antibiotics. Early diagnosis is imperative, but difficult.  相似文献   
82.
M Burke 《Hospitals》1991,65(6):29-30
For hospital officials who feel wronged by Medicare's payment system, a recent opportunity to appeal geographic status has stirred new hope for survival. Last September, the Health Care Financing Administration published interim final regulations detailing criteria hospitals have to meet to merit reclassification; hospitals had until Nov. 6, 1990, to file their appears. Now, officials are slogging through nearly 1,000 completed applications. "There has been pent-up demand for some review" of geographic classification, says one official.  相似文献   
83.
84.
Surgical resection offers distinct theoretical advantages as the "local" modality in treatment of Stage I and II small cell carcinoma of the lung. We have treated 10 such patients by initial resection since 1975; all survivors but one received adjuvant chemotherapy for the full course thereafter. One patient died of a pulmonary embolus; the other nine remain without evidence of disease from 7 to 69 months after resection. A trial was undertaken of extended indications for resection in selected patients with Stage III-M0 disease. Criteria for patient selection have been developed gradually; these exclude patients for reasons of refusal, physiological inadequacy, disease unsuited to gross total eradication, or lack of adequate initial response to chemotherapy. Of six patients who survived the exclusion criteria and underwent resection, one has had a relapse at 26 months. All others remain without evidence of disease, 5 to 25 months after the start of treatment. We believe that systematic patient selection on the basis of defined criteria will identify a subset of patients having markedly improved chances for disease control. This group may represent as many as half of the patients first presenting with localized or MO disease. Patients excluded as candidates for resection have continued to receive standard nonsurgical combined-modality therapy.  相似文献   
85.
BACKGROUND: Secondary hyperparathyroidism and its effects on bone and viscera are among the most important complications of end-stage renal disease. Despite its ubiquity, little is known about the treated natural history of the disorder. METHODS: We assembled a cohort of 310 patients with endstage renal disease on hemodialysis who were participants in one of four clinical trials of the phosphate binder sevelamer. Baseline parathyroid hormone levels were collected, and the relation between dialysis vintage and other clinical variables with parathyroid hormone were described. RESULTS: There was a direct relation between dialysis vintage and the severity of hyperparathyroidism. Other variables that were significantly associated with PTH on univariate analysis included age, African American race, Kt/V, and the serum concentrations of calcium, phosphate, and bicarbonate. Multivariable linear regression analysis yielded three significant predictors of PTH: calcium, phosphorus, and vintage (5.8% (4.0-7.5%) expected increase in PTH per year of vintage). The model R2 was 0.22. CONCLUSION: Dialysis vintage is a key determinant of the severity of secondary hyperparathyroidism. Vintage and certain laboratory variables should be considered in the evaluation of therapies aimed at modifying the treated natural history of this disorder.  相似文献   
86.
87.
Despite new advances in transplantation, complete venous thrombosis (VT) of the pancreas after simultaneous pancreas kidney (SPK) transplantation usually results in graft loss. Data are limited regarding the outcome and treatment of partial VT of the pancreas allograft. From July 1994 to December 1999, 126 patients with IDDM/end-stage renal disease underwent SPK with systemic bladder drainage at the University of Miami. We retrospectively reviewed our experience regarding the outcome and treatment options of partial VT of the pancreas allografts. From July 1994 to April 1997, partial VT was not seen in the first 66 SPK patients induced with anti-CD3 rnAb and oral or intravenous (i.v.) tacrolimus (TAC) in the operating room. From May 1997 to June 1999, 14 (29%) out of 48 patients had VT. These cases were identified following the i.v. use of TAC with anti-IL-2R antibody-induction therapy (7/15) or without (7/33). Partial thrombosis of the splenic vein (PTSV) was documented in 10 patients, 2 had complete thrombosis of the splenic vein (CTSV), 1 had partial thrombosis of the superior mesenteric vein (PTSMV), and 1 patient had PTSV and PTSMV. These were identified incidentally during routine color Doppler ultrasonography (CDU). None of these SPK recipients demonstrates a change in clinical parameters. The first 8 patients were systemically heparinized, followed by oral anticoagulation, except 1 patient with CTSV. He progressed to complete thrombosis of the pancreas allograft and was treated with percutaneous thrombectomy and urokinase infusion, followed by heparinization and oral anticoagulation. One patient required exploration for bleeding. In an attempt to reduce the morbidity of heparinization, we treated the next 6 patients with PTSV with aspirin followed by serial CDU. All 14 patients had preservation of the endocrine and exocrine pancreatic functions. CDU showed resolution with recanalization of the thrombosed vein(s). From July 1999 to December 1999, 12 SPK recipients were administered TAC orally with or without induction therapy with anti-IL-2R antibody. So far, in this group, VT has not been identified. In summary, a total of 14 out of 126 patients (11%) had isolated VT with a mean follow-up of 36.4 months. Based on our experience, we suggest that extensive VT after pancreas transplantation, including splenic and superior mesenteric VT, be treated with heparin and subsequent oral anticoagulation for 3 months. For more limited, partial splenic VT, aspirin may be sufficient. Follow-up CDU is critical for a successful outcome. The i.v. use of TAC appears to be a risk factor for the increased incidence of VT. Currently, using IL-2rmAb as induction, TAC is started orally on postoperative days 3 or 4 and aspirin on postoperative day 2.  相似文献   
88.
AIMS: To define outcome measures for auditing the clinical care of children and adolescents with insulin dependent diabetes mellitus (IDDM) and to assess the benefit of appointing a dedicated paediatric trained diabetes specialist nurse (PDSN). METHODS: Retrospective analysis of medical notes and hospital records. Glycaemic control, growth, weight gain, microvascular complications, school absence, and the proportion of children undergoing an annual clinical review and diabetes education session were assessed. The effect of the appointment of a PDSN on the frequency of hospital admission, length of inpatient stay, and outpatient attendance was evaluated. RESULTS: Children with IDDM were of normal height and grew well for three years after diagnosis, but grew suboptimally thereafter. Weight gain was above average every year after diagnosis. Glycaemic control was poor at all ages with only 16% of children having an acceptable glycated haemoglobin. Eighty five per cent of patients underwent a formal annual clinical review, of whom 16% had background retinopathy and 20% microalbuminuria in one or more samples. After appointing the PDSN the median length of hospital stay for newly diagnosed patients decreased from five days to one day, with 10 of 24 children not admitted. None of the latter was admitted during the next year. There was no evidence of the PDSN affecting the frequency of readmission or length of stay of children with established IDDM. Non-attendance at the outpatient clinic was reduced from a median of 19 to 10%. CONCLUSIONS: Outcome measures for evaluating the care of children with IDDM can be defined and evaluated. Specialist nursing support markedly reduces the length of hospital stay of newly diagnosed patients without sacrificing the quality of care.  相似文献   
89.
OBJECTIVES: The amount of adipose tissue influences pubertal development and fertility in girls. A candidate for mediating this is the hormone leptin, derived from adipocytes. This work was carried out to determine whether the leptin concentration in serum is regulated during pubertal development. SUBJECTS AND METHODS: Serum concentrations of leptin were determined by radioimmunoassay in a sample of 252 healthy children representing all pubertal stages. RESULTS: Serum leptin concentrations correlated directly with age (r = 0.53), body mass index (BMI) (r = 0.71), and weight for height SD score (r = 0.44) in girls and with BMI (r = 0.33) and weight for height SD score in boys (r = 0.36). Leptin concentrations increased with pubertal development in girls, resulting in significantly higher concentrations at pubertal stages 4 and 5 than at the prepubertal stage, whereas there was no change in the boys. CONCLUSIONS: Serum leptin concentrations increased during pubertal development in the girls, but remained constant in the boys. Whether the increase in serum leptin concentrations in girls is of importance for, or a consequence of, pubertal development is still to be determined.  相似文献   
90.
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