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   6796篇
  免费   531篇
  国内免费   8篇
耳鼻咽喉   183篇
儿科学   167篇
妇产科学   199篇
基础医学   864篇
口腔科学   163篇
临床医学   647篇
内科学   1059篇
皮肤病学   211篇
神经病学   479篇
特种医学   200篇
外科学   841篇
综合类   77篇
一般理论   5篇
预防医学   888篇
眼科学   53篇
药学   627篇
中国医学   8篇
肿瘤学   664篇
  2022年   83篇
  2021年   161篇
  2020年   82篇
  2019年   133篇
  2018年   160篇
  2017年   126篇
  2016年   129篇
  2015年   143篇
  2014年   186篇
  2013年   252篇
  2012年   368篇
  2011年   343篇
  2010年   183篇
  2009年   156篇
  2008年   321篇
  2007年   315篇
  2006年   318篇
  2005年   286篇
  2004年   305篇
  2003年   270篇
  2002年   265篇
  2001年   171篇
  2000年   143篇
  1999年   149篇
  1998年   67篇
  1997年   60篇
  1996年   55篇
  1995年   49篇
  1994年   51篇
  1993年   47篇
  1992年   119篇
  1991年   133篇
  1990年   132篇
  1989年   121篇
  1988年   108篇
  1987年   115篇
  1986年   112篇
  1985年   94篇
  1984年   92篇
  1983年   69篇
  1982年   53篇
  1981年   53篇
  1980年   48篇
  1979年   65篇
  1978年   62篇
  1975年   47篇
  1974年   47篇
  1973年   45篇
  1972年   46篇
  1971年   50篇
排序方式: 共有7335条查询结果,搜索用时 78 毫秒
81.
The concept of comorbidity of anxiety and depression was examined as it relates to specialty clinics, a growing trend as mental health care providers attempt to compete for patients and provide efficient and specialized treatments. Twenty-nine patients from an anxiety clinic were compared with 23 patients from a mood disorders clinic in a university-based outpatient setting. Axis I diagnoses obtained by structured clinical interview for DSM-III-R were generally consistent with each specialty clinic. Incidence of diagnosable comorbid anxiety and mood disorders was not significantly different for the two clinics and within the range cited (11-78%) in several other studies drawing from various patient populations. Similarly, in comparing self-reported symptoms on three rating scales using Student's tests, authors found elevated symptoms of both depression and anxiety in both clinic populations. The importance of addressing the needs of patients with co-occurring diagnoses and symptoms within a specialty clinic is discussed as it pertains to treatment and research.  相似文献   
82.
Tucker LL  Cohen MR  Davis NM 《Hospital pharmacy》1994,29(11):984, 986-988, 991
Patients can be harmed and even killed when a medication error occurs. The following questions are based on actual errors which have been reported through the Medication Error Reporting Program (MERP). This teaching tool is intended as a take home test to make newly hired pharmacists aware of common medication errors. An informed practitioner is another layer of safety in decreasing the possibility of a medication error occurring.  相似文献   
83.
Multifocal atrial tachycardia is a difficult clinical problem generally associated with acute cardiorespiratory illness. The purpose of this study was to assess the feasibility and clinical utility of atrioventricular junction ablation plus permanent transvenous pacemaker implantation as therapy for uncontrolled refractory multifocal atrial tachycardia. Three patients with uncontrolled refractory multifocal atrial tachycardia underwent atrioventricular junction ablation plus permanent transvenous pacemaker implantation. Complications and outcome of each procedure was monitored and both objective and subjective assessment of physical functional capacity was assessed by a semiquantitative examination. Ablation procedures controlled the ventricular response in all patients. There were no complications related to the ablation procedure or implantation of permanent transvenous pacing system. All patients demonstrated subjective improvement in symptoms. Palpitations were virtually eradicated in these patients and all enjoyed significant improvements in rest and effort dyspnea, exercise tolerance and asthenia. Objective assessment of functional class also demonstrated significant improvements. Atrioventricular ablation plus permanent transvenous pacing offers a safe and effective therapy for uncontrolled refractory multifocal atrial tachycardia.  相似文献   
84.
This article describes a case of a laparoscopic injury and the ensuing litigation. Data from the hospital report and the testimony of witnesses are presented. In the next issue of this Journal, the results of the jury finding will be presented as Part II.  相似文献   
85.
OBJECTIVE: To evaluate, in compliant patients, the pharmaceutical costs of treating obesity with fenfluramine/mazindol, fenfluramine/phentermine, caffeine/ephedrine, or mazindol relative to the pharmaceutical costs of treating obesity-related comorbid conditions and reducing cardiovascular risk. METHODS AND PROCEDURES: Subjects were between 18 and 60 years of age with a BMI of >30 kg/m2. Pharmaceutical costs were evaluated in 73 of 220 subjects taking medications for diabetes, hyperlipidemia, or hypertension before and after treatment using fenfluramine with mazindol or phentermine. The pharmaceutical cost of weight loss, cardiac risk reduction, and low-density lipoprotein (LDL) cholesterol reduction was calculated for fenfluramine with mazindol or phentermine, caffeine with ephedrine, or mazindol alone, and compared to approved lipid-lowering medications. RESULTS: Losses of 6% to 10% of initial body weight reduced pharmacy costs $122.64/month for insulin treated diabetes, $42.92/month for sulfonylurea-treated diabetes, $61.07/month for hyperlipidemia treated with medication, and $0.20/month for hypertension treated with medication. Blood pressure and laboratory evidence of insulin resistance improved in all medication groups. Caffeine/ephedrine was most cost-effective of the three treatments in reducing weight, cardiac risk, and LDL cholesterol. DISCUSSION: Obesity medications produced a substantial weight loss in compliant patients and resulted in a net pharmaceutical cost savings compared to treating obesity related comorbid conditions.  相似文献   
86.
This report is concerned with control of cell shaping, positioning, and cytoskeletal integration in a highly ordered cochlear neuroepithelium. It is largely based on investigations of events that occur during abnormal morphogenesis of the organ of Corti in the Bronx waltzer (bv/bv) mutant mouse. The organ's sensory hair cells and adjacent supporting cells ordinarily construct a spatially elaborate and supracellularly integrated cytoskeletal framework. Large microtubule bundles are connected to cytoskeletal components in neighbouring cells by actin-containing meshworks that link them to substantial arrays of adherens junctions. In bv/bv mice, degeneration and loss of most inner hair cells and outer pillar cells occurs during organ development. These cells flank each side of a row of inner pillar cells that respond by upregulating assembly of their actin-containing meshworks. This only occurs in surface regions where they no longer contact cell types involved in construction of the cytoskeletal framework. The meshworks are larger and exhibit a more extensive sub-surface deployment than is normally the case. Hence, assembly of intercellular cytoskeletal connecting components can proceed without contact with appropriate cell neighbours but termination of assembly is apparently subject to a negative feedback control triggered by successful completion of intercellular connection with the correct cell neighbours. In addition, inner pillar cells compensate for loss of cell neighbours by interdigitating and overlapping each other more extensively than is usually the case to increase opportunities for generating adherens junctions. Certain adherens junctions in the organs of +/+ and bv/bv mice exhibit features that distinguish them from all previously described cell junctions. The dense plaques on their cytoplasmic faces are composed of aligned ridges. We suggest that they are called ribbed adherens junctions. Perturbations of cell shaping and positioning indicate that loss of inner hair cells is the primary consequence of the bv mutation. Most of the other abnormalities can be understood in terms of a secondary sequence of morphogenetic aberrations (precipitated by loss of inner hair cells). These aberrations provide new information about the ways in which supporting cells help to control hair cell positioning.  相似文献   
87.
Our objective was to determine the incidence of complications in postoperative patients who were either normothermic or hypothermic. A recent, widely publicized paper concluded that the maintenance of normothermia could reduce the incidence of infectious complications and shorten hospitalization in patients undergoing colorectal surgery. However, some controversy arose regarding the methods of this paper. Patients were deliberately rendered hypothermic, were given more than 3.5 days of prophylactic antibiotics and were transfused significantly more units of blood. We reviewed the charts of 150 consecutive patients who underwent elective partial or subtotal colectomy with primary anastomosis. Among the key items analyzed were intraoperative and postoperative temperature, use of warming devices, duration of surgery, transfusions, interval to oral intake and bowel function, length of stay, complications, infections, and laboratory values. Hypothermia was defined as intraoperative temperature <95.5 degrees F. There were 101 normothermic patients and 49 hypothermic patients. Hypothermic patients had a mean age of 68.7 years versus 66.8 for the normothermic patients (P = 0.472). Comorbidities were similar in both groups. Warming devices were used in >90 per cent of the patients in both groups. The rates of postoperative infections and complications were similar in both groups. Postoperative lengths of stay were also not different. Despite finding that one-third of our patients were hypothermic during elective colon resection, hypothermia had no effect on outcome variables. In contrast to the previous study, the incidence of infectious complications was identical in our patients. Before ascribing postoperative complications and increased resource utilization as adverse effects of hypothermia, further studies are indicated.  相似文献   
88.
89.
90.
OBJECTIVE: To test the hypothesis that 55-70 y old male longterm exercisers (LE) have higher resting metabolic rates (RMR) than longterm nonexercisers (LNE). DESIGN: A power analysis demonstrated that this cross-sectional study required 12 subjects per group to detect a 10% RMR difference (kJ x kg FFM(-1) x d(-1)) between the LE and LNE (power = 0.8;alpha = 0.05). SUBJECTS: Twelve LE (X +/- s.d.; 63.5+/-3.4 y; 1.75+/-0.06 m; 69.01+/-8.24 kg; 20.4+/-4.9 %BF) and 12 LNE (63.6+/-5.6 y; 1.72+/-0.07 m; 79.44 12.4 kg; 29.6 4.4 %BF) were recruited from advertisements placed in a newspaper and on university and community noticeboards. INTERVENTIONS: Measurements were conducted for: RMR using the Douglas bag technique; body composition via a four compartment model which is based on determination of body density, total body water and bone mineral mass; and aerobic fitness using a submaximal work test on a cycle ergometer. RESULTS: The LE (93.00+/-7.16 kJ x kg(-1) x d(-1)) registered a significantly greater (P = 0.04) RMR than the LNE (84.70+/-11.23 kJ x kg(-1) x d(-1)) when energy expenditure was expressed relative to body mass, but this difference disappeared (P = 0.55) when the data were corrected for the non-zero intercept of the graph of RMR (MJ/d) against body mass. ANCOVA with FFM as the covariate also indicated that the RMR (MJ/d) difference between the groups was not statistically significant (P = 0.28). The adjusted means for the LE and LNE were 6.39 and 6.62 MJ/d, respectively. CONCLUSIONS: There are no RMR (MJ/d) differences between LE and LNE 54-71 y old males when statistical control is exerted for the effect of FFM and the higher value of the former group for RMR normalised to body mass disappears when this ratio is corrected for statistical bias.  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