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   506篇
  免费   24篇
  国内免费   9篇
耳鼻咽喉   1篇
儿科学   13篇
妇产科学   3篇
基础医学   63篇
口腔科学   10篇
临床医学   46篇
内科学   74篇
皮肤病学   5篇
神经病学   135篇
特种医学   46篇
外科学   22篇
综合类   55篇
预防医学   32篇
眼科学   4篇
药学   17篇
中国医学   1篇
肿瘤学   12篇
  2022年   5篇
  2021年   2篇
  2020年   3篇
  2019年   2篇
  2018年   5篇
  2017年   6篇
  2016年   8篇
  2015年   11篇
  2014年   10篇
  2013年   21篇
  2012年   19篇
  2011年   21篇
  2010年   15篇
  2009年   28篇
  2008年   21篇
  2007年   25篇
  2006年   24篇
  2005年   18篇
  2004年   21篇
  2003年   15篇
  2002年   11篇
  2001年   20篇
  2000年   16篇
  1999年   20篇
  1998年   19篇
  1997年   22篇
  1996年   12篇
  1995年   7篇
  1994年   4篇
  1993年   6篇
  1992年   8篇
  1991年   7篇
  1990年   3篇
  1989年   8篇
  1988年   11篇
  1987年   9篇
  1986年   6篇
  1985年   10篇
  1984年   4篇
  1983年   10篇
  1982年   9篇
  1981年   4篇
  1980年   2篇
  1979年   3篇
  1977年   2篇
  1975年   3篇
  1958年   11篇
  1957年   4篇
  1952年   2篇
  1951年   1篇
排序方式: 共有539条查询结果,搜索用时 15 毫秒
91.
92.
Malaspina A  Rinaldo CR  Sekaly RP  Flores J  D'Souza PM 《Vaccine》2011,29(29-30):4647-4653
Although clinical trials are the ultimate way to prove vaccine safety and efficacy, the complexity, cost and time required to develop a product to enter human trials demand a serious, long-term investment. Lack of knowledge on immune correlates of protection from HIV infections makes investments in HIV vaccine research significantly risky. Preclinical testing of HIV vaccines is routinely carried out in non-human primate models however these studies have a significant cost and their predictive value is still questionable. The potential value of screening new HIV-1 vaccine candidates on human cells and tissues via high throughput in vitro systems that allow rapid, cost-effective and accurate predictions of in vivo immune responses would be enormous. A one-day workshop was convened by Division of AIDS, National Institutes of Health on August 4, 2010 to address the benefits and challenges of assessing HIV-1 vaccine responses in alternative ways. Consideration was given to the use of various in vitro model systems, human mucosal tissue explants and humanized mouse models as ways to predict immunogenicity and efficacy of HIV-1 vaccines early in the development process, and support decisions on whether a product may be worthy of moving into non-human primates or human trials. This report summarizes the outcome of the workshop.  相似文献   
93.
Introduction: Chronic kidney disease (CKD) is associated with significant morbidity and mortality. Screening and detection of early stages of CKD can help institute interventions that may delay the progression of the disease. One aim was to study the prevalence of early stages of CKD in the Army.Methods: A cross-sectional study ofArmy Personnel in an Army cantt in Central India was carried out. All participants filled a structured questionnaire and anthropometric data was collected. Investigative profile included routine urine exam, semi-quantitative microalbuminuria (MAU), serum creatinine, lipid profile and fasting blood glucose. Glomerular Filteration rate (eGFR) was calculated using the Modification of Diet in Renal Diseases (MDRD) study equation.Result: A total of 1920 subjects were examined with 731 (38.07%) from Arms and 1189 (6I.93%) from Services. 348 were excluded and of the remaining 1572 subjects, 141 (8.97%) had MAU and 157 (9.99%) had deranged Albumin Creatinine Ratio (ACR). Mean eGFR by MDRD equation was 102 ± 25.84 ml/min/1.73m2. Early CKD was seen in 150 (9.54%) with 84 (5.34%) in stage I CKD, 55 (3.5%) in stage II and 11 (0.7%) in stage III. Multiple logistic regression showed BMI > 23, the presence of DM and HTN were independent risk factors for CKD.Conclusion: 9.54 % of healthy army personnel were found to have early stages of CKD. Institution of screening programs can result in early detection of CKD.  相似文献   
94.
Patients with comorbid schizophrenia and panic symptoms share a distinct clinical presentation and biological characteristics, prompting some to propose panic psychosis as a separate subtype of schizophrenia. Less is known about these patients' neuropsychological profiles, knowledge of which may facilitate target-specific treatments and research into the etiopathophysiology for such cases. A total of 255 schizophrenia patients with panic disorder (n=39), non-panic anxiety disorder (n=51), or no anxiety disorder (n=165) were assessed with the Wechsler Adult Intelligence Scale-Revised, the Wisconsin Card Sorting Test, the Trail Making Test, the Controlled Oral Word Association Test, the Animal Naming subtest of the Boston Diagnostic Aphasia Examination, and the Wechsler Memory Scale-Revised. Psychotic symptoms were assessed with the Positive and Negative Syndrome Scale. Patients with panic disorder demonstrated a higher verbal IQ and better problem solving, set switching, delayed recall, attention, and verbal fluency as compared to schizophrenia patients without comorbid anxiety. The schizophrenia-panic group reported a higher level of dysthymia on stable medication. Our findings suggest that patients with schizophrenia and comorbid panic disorder exhibit distinct cognitive functioning when compared to other schizophrenia patients. These data offer further support for a definable panic-psychosis subtype and suggest new etiological pathways for future research.  相似文献   
95.
96.
97.
Metabolic Brain Disease - Succinic semialdehyde dehydrogenase deficiency (SSADHD) is a rare autosomal recessive disorder of γ-aminobutyric acid (GABA) catabolism caused by mutations in the...  相似文献   
98.
This prospective study analyzes the neonatal outcome in deliveries complicated by meconium stained amniotic fluid. In a study of 1000 live born deliveries, meconium staining of amniotic fluid was seen in 50 (5%) deliveries. Out of these, 20 newborns (40%) developed classical signs of meconium aspiration syndrome and were managed according to a predetermined protocol. Multiparity, term deliveries, use of sedatives in mother, intrauterine growth retardation and prolonged labour were some of the risk factors for development of meconium aspiration syndrome in newborns. This study highlights the need for review of management protocol in newborns after meconium staining of the amniotic fluid, including the use of prophylactic antibiotics.KEY WORDS: Amniotic fluid, Delivery, Meconium aspiration, Respiratory distress syndrome  相似文献   
99.
Sixteen strains of Vibrio cholerae were isolated from cases of diarrhoea. Out of these, 12 (75%) were identified as Vibrio cholerae 0139 synonym Bengal and 4 (25%) as Vibrio cholerae El Tor by standard biochemical and serological tests. Modified CAMP reaction in sheep blood agar showed that 0139 produced moderate hemolysis, El Tor produced wider zone of hemolysis whereas Classical Vibrio cholerae produced no zone of hemolysis (CAMP negative). Break point minimum inhibitory concentration (MIC) by agar dilution method showed that all 0139 strains were resistant to ampicillin 8 mg/L, streptomycin 1 mg/L, chloramphenicol 8 mg/L, sulphamethoxazole 32 mg/L and trimethoprim 0.3-128 mg/L, 58.3% were sensitive to gentamicin 1 mg/L, and all were sensitive to norfloxacin 1 mg/L and cefotaxime 1 mg/L. Resistance to trimethoprim, sulphamethoxazole, ampicillin and gentamicin in 5 strains could be transferred to E coli K-12 by conjugation experiment at a rate of 5×10−6 to 4×10−3. Distinct plasmid bands of 35.8 mega daltons could be seen in agarose gel electrophoresis.KEY WORDS: CAMP test, Drug resistance, Plasmid, Vibrio cholerae 0139.  相似文献   
100.
Schizophrenia is an etiologically heterogeneous syndrome. It has a strong genetic component and exists in clinically indistinguishable familial and nonfamilial (sporadic) forms. A significant role for de novo genetic mutations in genetic schizophrenia vulnerability is suggested by a strong monotonic increase in schizophrenia risk with advancing paternal age. However, an alternative explanation for the paternal age effect in schizophrenia is that childbearing is delayed in fathers who themselves have genetic schizophrenia vulnerability. In this study, we compared paternal birth ages between patient groups with familial (n = 35) and sporadic (n = 68) patients with DSM-IV schizophrenia from an inpatient schizophrenia research unit. If later age of fathering children is related to having some genetic schizophrenia vulnerability, then paternal birth age should be later in familial schizophrenia cases than in sporadic cases, and any association of father's age and schizophrenia risk in offspring would be a spurious finding, unrelated to etiology. However, if de novo mutations cause sporadic schizophrenia, then patients without a family history of schizophrenia would have older fathers than familial patients. We found that patients without a family history of schizophrenia had significantly older fathers (4.7 years) than familial patients; so later childbirth was not attributable to parental psychiatric illness. These findings support the hypothesis that de novo mutations contribute to the risk for sporadic schizophrenia.  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