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   4423篇
  免费   472篇
  国内免费   13篇
耳鼻咽喉   14篇
儿科学   171篇
妇产科学   61篇
基础医学   511篇
口腔科学   73篇
临床医学   605篇
内科学   924篇
皮肤病学   198篇
神经病学   275篇
特种医学   358篇
外科学   521篇
综合类   117篇
一般理论   2篇
预防医学   464篇
眼科学   39篇
药学   401篇
中国医学   8篇
肿瘤学   166篇
  2021年   61篇
  2020年   38篇
  2019年   49篇
  2018年   73篇
  2017年   44篇
  2016年   76篇
  2015年   72篇
  2014年   92篇
  2013年   126篇
  2012年   177篇
  2011年   194篇
  2010年   131篇
  2009年   125篇
  2008年   204篇
  2007年   168篇
  2006年   184篇
  2005年   173篇
  2004年   162篇
  2003年   157篇
  2002年   133篇
  2001年   140篇
  2000年   143篇
  1999年   119篇
  1998年   91篇
  1997年   84篇
  1996年   94篇
  1995年   87篇
  1994年   70篇
  1993年   77篇
  1992年   99篇
  1991年   82篇
  1990年   92篇
  1989年   83篇
  1988年   92篇
  1987年   89篇
  1986年   98篇
  1985年   103篇
  1984年   66篇
  1983年   75篇
  1982年   56篇
  1981年   37篇
  1980年   34篇
  1979年   42篇
  1978年   43篇
  1977年   44篇
  1976年   48篇
  1975年   56篇
  1974年   49篇
  1973年   34篇
  1972年   32篇
排序方式: 共有4908条查询结果,搜索用时 250 毫秒
81.
Although the majority of trauma patients are discharged home rather than to a rehabilitation facility, the timeliness of their return to function (RTF) has received little study. The present prospective study attempted to identify those factors that would predict delayed RTF. The study group consisted of patients admitted to a level I trauma center for at least 24 hours, who were of working age (18-64 years), who passed a cognitive screening examination, and who were discharged home. Demographic data and psychological profiles were collected on all participants. Patients were followed by telephone at approximately 1 1/2, 3, and 6 months after discharge. Five hundred seventy patients were entered into the study; complete follow-up data were available for 441. Statistical methods were modeled after survival analysis using a proportional hazards multiple regression to identify variables prognostic of RTF time. This type analysis is independent of time, providing a "risk" of RTF at any point in time after the injury. It also allowed the calculation a relative hazards ratio (RHR), which quantifies the impact of a prognostic variable on RTF time. Injury Severity Score (ISS) and age were found to be associated with RTF (p < 0.0001 for each). After correcting for ISS and age, five additional factors were found to be associated with RTF. Higher educational level and living in a non-family household were associated with faster RTF. Less than 100% income replacement by disability income, pre-injury hostility, and litigation related to the injury were associated with slower RTF. There were a number of other demographic, work-related, and psychosocial factors that were not related with RTF.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
82.
We examined different strategies for identifying nonfatal family and intimate assaults (FIAs) in police data. Police most often classify such incidents in the "assault" category, but they also use other crime categories. We estimated that, during 1984, 3300 FIAs (or 837 per 100,000 population) occurred in Atlanta. Of those, 77% were classified as assaults; 23% were classified in nonassault categories. Research measuring the magnitude of FIAs should take into account incidents classified in nonassault crime categories.  相似文献   
83.
84.
A major complication of cholestasis is fat malabsorption related to decreased intestinal bile acids, which leads to malnutrition and fat-soluble vitamin deficiency. The impaired excretion of bile acids leads to a low intraluminal micellar concentration that causes long-chain triglyceride lipolysis and absorption to be ineffective. Medium-chain triglycerides (MCTs) are more readily absorbed when there are low concentrations of bile acids and therefore are a good source of fat calories; MCTs can be administered as MCT-containing formulas. In those children who are unable to take sufficient calories by mouth, it is important to start nocturnal enteral feeding to improve nutritional status. In infants with cholestasis, the absorption of fat-soluble vitamins (A, D, E and K) that require bile acids is also impaired, and supplementation is mandatory. Vitamin K deficiency may be responsible for hypoprothrombinaemia, which may lead to bleeding diathesis, Vitamin K (phytomenadione) should therefore be promptly administered intravenously, at a dose of 1 mg. Chronic vitamin E (α-tocopherol) deficiency is associated with a progressive neuromuscular syndrome that can cause cerebellar ataxia, areflexia and peripheral neuropathy. Supplements are given orally in doses of 3–5 times the normal requirement if cholestasis is incomplete. In complete cholestasis, supplements must be given intramuscularly at monthly intervals. In infants who fail to thrive, dietary supplements of carbohydrate polymers and MCTs are required.  相似文献   
85.
目的:研究中国健康成年男性志愿者单剂静滴甲磺酸加替沙星注射液的药代动力学。方法:按药物临床试验管理规范(GCP)指导原则设计试验方案。选择9名受试者分别依次单刘静滴100,200和400mg的甲磺酸加替沙星注射液后,应用HPLC测定血药浓度,采用3P97软件进行数据处理,求出药代动力学参数。结果:受试者分别给药后,药-时曲线符合二房室模型,主要药代动力学参数C_(max)分别为1.10±0.19,2.17±0.33和3.16±0.47mg·L~(-1);t_(1/2)β分别为7.42±1.99,8.41±2.72和8.46±2.83h;AUC_(0-∞)分别为4.45 ±0.71,11.10±1.81和23.03±3.83mg h·L~(-1)。原形药主要经肾排泄,48h尿药累积排泄率分别为(43.08±15.79)%,(51.33±23.69)%和(45.67±18.22)%。结论:9名静滴甲磺酸加替沙星注射液后,药-时曲线符合二房室模型。提示甲磺酸加替沙星在100~400mg剂量内药物体内过程基本呈线性动力学特征而无饱和性,主要排泄途径为肾脏。  相似文献   
86.
原发性乳腺恶性淋巴瘤六例临床分析   总被引:8,自引:0,他引:8  
目的 分析原发性乳腺恶性淋巴瘤的临床特点,探讨其诊断、分期和治疗方法。方法回顾分析我院自1995~2002年收治的6例原发性乳腺恶性淋巴瘤和1980~2002年国内主要文献报道的279例原发性乳腺恶性淋巴瘤的临床特征、诊断情况和治疗方法,进行对比分析。结果 285例病例均为非霍奇金淋巴瘤(NHL),免疫学检查证实有282例为B细胞源性(98.9%);女性268例,占94.0%;病灶位于右侧163例,占57.2%;Ⅰ期和Ⅱ期的原发性乳腺恶性淋巴瘤占89.8%。经手术、化疗、放疗等综合治疗后,生存期2~206个月,中位生存期最短23个月,最长56个月。结论 原发性乳腺恶性淋巴瘤绝大部分为B细胞源性非霍奇金淋巴瘤(NHL),Ⅰ期、Ⅱ期多见。对于原发性乳腺恶性淋巴瘤,诊断是关键,确诊后经手术、化疗、放疗等综合治疗,可以获得较长的生存期,疗效十分满意。  相似文献   
87.
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible.  相似文献   
88.
89.
Ethics in practice   总被引:1,自引:0,他引:1  
H. K. is a ninety-two-year-old woman with Alzheimer's disease and mild hypertension. She resides at a nursing home, where she transfers from bed to chair with maximal assistance. She presents to our emergency department with a painful right hip. Physical examination demonstrates a confused, elderly patient with significant right hip pain and shortening and external rotation of the lower extremity. Radiographs demonstrate a displaced intertrochanteric hip fracture. The patient lacks the capacity for informed consent. Her family is contacted to obtain consent for insertion of a compression screw. The family refuses to give consent, stating that the patient is too old and the surgery is too dangerous.  相似文献   
90.
Background: The purpose of the present paper was to describe the clinical manifestations and treatment of patients with panniculitis. Methods: From January 1983 to December 2002, 4294 patients were treated for pediatric rheumatological diseases at Pediatric Rheumatology Unit, University of São Paulo, Brazil. Of these, 35 children and adolescents (0.8%) presented with panniculitis: erythema nodosum (EN) or Weber–Christian disease (WCD). Clinical characteristics, laboratory exams, biopsy of the lesion, treatment and clinical course were studied. Results: Of the 35 patients, 29 presented with EN and six with WCD, one of these with cytophagic histiocytic panniculitis. Mean age at symptom onset was 85 months (6–204 months) and the mean duration of follow up was 55 months (1–144 months). All the patients presented with inflammatory subcutaneous nodules. The patients with WCD presented with systemic manifestations and cutaneous atrophy. The principal etiologies of EN were streptococcal infection (42%), undetermined (13.5%), pulmonary tuberculosis (10%), and acute rheumatic fever (10%). Biopsy of the nodules indicated septal panniculitis in 14 patients with EN and lobular panniculitis without vasculitis in the patients with WCD, one of which had cytophagic histiocytic panniculitis. There was recurrence in 11 patients (38%) with EN and in all those with WCD. Non‐steroidal anti‐inflammatory drugs were used in 15 patients with EN and corticosteroids and/or immunosuppressive drugs in the six patients with WCD. Three patients died. Conclusions: EN is the most frequent panniculitis, with a benign course and is mainly associated with infections. WCD is a severe disease, with systemic involvement, that proceeds with cutaneous atrophy and requires the use of corticosteroids and or immunosuppressive drugs.  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