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   10082篇
  免费   881篇
  国内免费   12篇
耳鼻咽喉   258篇
儿科学   554篇
妇产科学   316篇
基础医学   1085篇
口腔科学   650篇
临床医学   899篇
内科学   1879篇
皮肤病学   261篇
神经病学   811篇
特种医学   435篇
外国民族医学   2篇
外科学   2061篇
综合类   44篇
一般理论   3篇
预防医学   513篇
眼科学   243篇
药学   588篇
中国医学   14篇
肿瘤学   359篇
  2023年   150篇
  2022年   97篇
  2021年   268篇
  2020年   224篇
  2019年   267篇
  2018年   474篇
  2017年   371篇
  2016年   465篇
  2015年   490篇
  2014年   556篇
  2013年   926篇
  2012年   507篇
  2011年   511篇
  2010年   513篇
  2009年   316篇
  2008年   273篇
  2007年   206篇
  2006年   361篇
  2005年   314篇
  2004年   202篇
  2003年   183篇
  2002年   217篇
  2001年   285篇
  2000年   265篇
  1999年   266篇
  1998年   193篇
  1997年   131篇
  1996年   158篇
  1995年   104篇
  1994年   126篇
  1993年   94篇
  1992年   107篇
  1991年   115篇
  1990年   91篇
  1989年   73篇
  1988年   74篇
  1987年   76篇
  1986年   71篇
  1985年   53篇
  1984年   54篇
  1983年   50篇
  1982年   49篇
  1981年   46篇
  1980年   43篇
  1979年   51篇
  1978年   29篇
  1977年   35篇
  1976年   27篇
  1973年   35篇
  1967年   24篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
992.
Background: Inpatient aggression among female forensic psychiatric patients has been shown to be associated with self-harm, that is considered to be a historical risk factor for violence. Research on associations between previous or current self-harm and different types of inpatient aggression is missing.

Aim: The aim of this register study was to investigate the prevalence of self-harm and the type of inpatient aggression among female forensic psychiatric inpatients, and to study whether the patients’ self-harm before and/or during forensic psychiatric care is a risk factor for inpatient aggression.

Methods: Female forensic psychiatric patients (n?=?130) from a high security hospital were included.

Results: The results showed that 88% of the female patients had self-harmed at least once during their life and 57% had been physically and/or verbally aggressive towards staff or other patients while in care at the hospital. Self-harm before admission to the current forensic psychiatric care or repeated self-harm were not significantly associated with inpatient aggression, whereas self-harm during care was significantly associated with physical and verbal aggression directed at staff.

Conclusions: These results pointed towards self-harm being a dynamic risk factor rather than a historical risk factor for inpatient aggression among female forensic psychiatric patients. Whether self-harm is an individual risk factor or a part of the clinical risk factor ‘Symptom of major mental illness’ within the HCR-20V3 must be further explored among women. Thus, addressing self-harm committed by female patients during forensic psychiatric care seems to be important in risk assessments and the management of violence, especially in reducing violence against staff in high-security forensic psychiatric services.  相似文献   
993.
994.
995.
Summary Clonal chromosomal evolution was observed in a 16-year-old boy suffering from Ph1-positive CML. An isodicentric Ph1 chromosome appeared 20 weeks after the initial diagnosis. At that time an allogeneic bone marrow transplantation was performed.Thereafter, during an observation period of more than 13 months, chromosome analyses showed neither the Ph1 chromosome nor the abnormal isodicentric variant. Close cytogenetic monitoring is suggested to reveal early unfavourable prognostic signs of the onset of blast crisis before it becomes evident in the bone marrow morphology.  相似文献   
996.
Lentiviral vectors have turned out to be an efficient method for stable gene transfer in vitro and in vivo. Not only do fields of application include cell marking and tracing following transplantation in vivo, but also the stable delivery of biological active proteins for gene therapy. A variety of cells, however, need immediate transplantation after preparation, for example, to prevent cell death, differentiation or de-differentiation. Although these cells are usually washed several times following lentiviral transduction, there may be the risk of viral vector shuttle via transplanted cells resulting in undesired in vivo transduction of recipient cells. We investigated whether infectious lentiviral particles are transmitted via ex vivo lentivirally transduced cells. To this end, we explored potential viral shuttle via ex vivo lentivirally transduced cardiomyocytes in vitro and following transplantation into the brain and peripheral muscle. We demonstrate that, even after extensive washing, infectious viral vector particles can be detected in cell suspensions. Those lentiviral vector particles were able to transduce target cells in transwell experiments. Moreover, transmitted vector particles stably transduced resident cells of the recipient central nervous system and muscle in vivo. Our results of lentiviral vector shuttle via transduced cardiomyocytes are significant for both ex vivo gene therapy and for lentiviral cell tracing, in particular for investigation of stem cell differentiation in transplantation models and co-cultivation systems.  相似文献   
997.
Fatty acids are promptly taken up, metabolised and eliminated by healthy cardiomyocytes. Cardiomyopathy, coronary heart disease and chronic rejection are known to be associated with an impaired fatty acid metabolism. It was the aim of this study to investigate fatty acid metabolism in a rat heart transplant model and to correlate scintigraphic findings with histological changes. After right-side nephrectomy of Lewis recipients Brown Norway cardiac allografts were anastomosed to the renal vessels. Animals were given no immunosuppression. The metabolism of carrier-free 17-123 jodo-heptadecanoic acid (123J-HDA) with a specific activity of >2×1017 Bq/ml was scintigraphically measured between days 1 and 11. An increase in the grade of rejection was observed over time. Fifty-six frames of 30 s duration each were recorded. For the region of interest (native heart, transplanted heart, left kidney) frames 10–56 were superimposed, time-activity curves generated and monoexponentially fitted. Furthermore, elimination half-life and intercepts were calculated. Following scintigraphic evaluation the animals were killed and graft as well as native hearts excised for histological examination. The uptake of the tracer identified severe grades of rejection. Elimination half-life of the tracer was twice as long from hearts with mild rejection and more than 14 times as long in severe rejection compared with no rejection. Elimination half-life and amplitude did not permit discrimination between grades 1, 2 and 3 a, but significantly decreased in groups 3 b and 4. This method therefore seems to be a valuable tool for the noninvasive detection of severe acute cardiac allograft rejection. Since fatty acid metabolism is clearly stress-dependent it remains to be seen whether this method allows detection of earlier rejection in loaded hearts.  相似文献   
998.
Aggressive behavior is a basic form of human social interaction, yet little is known about its neural substrates. We used a laboratory task to investigate the neural correlates of reactive aggression using functional magnetic resonance imaging. The task is disguised as a reaction-time competition between the subject and two opponents and entitles the winner to punish the loser. It seeks to elicit aggression by provocation of the subject. As each single trial in this task is separated into a decision phase, during which the severity of the prospective punishment of the opponent is set, and an outcome phase, during which the actual punishment is applied or received, the paradigm enables us to analyze the neural events during each of these phases. Specific neural responses in areas related to negative affect, cognitive control and reward processing provide additional information about the cognitive, emotional and motivational processes underlying reactive aggressive behavior and afford us with the possibility to test and expand theories on aggression such as the General Aggression Model.  相似文献   
999.
OBJECTIVE: To determine the age- and sex-specific prevalence of impaired fasting glycemia, impaired glucose tolerance, screen-detected diabetes, and known diabetes in a Danish population aged 30-60 years and to examine the phenotype and the cardiovascular risk profile in individuals with impaired glucose regulation. RESEARCH DESIGN AND METHODS: In the Inter99 study, 13,016 inhabitants living in Copenhagen County were invited. All participants underwent anthropometric measurements, blood samples, and a 75-g standardized oral glucose tolerance test. RESULTS: The age-specific prevalences in men were as follows: impaired fasting glycemia: 1.4-16.3%; impaired glucose tolerance: 6.9-17.8%; screen-detected diabetes: 0.7-9.7%; and known diabetes: 0-5.8%. The corresponding figures in women were 0-5.1, 10.5-17.3, 0.6-6.3, and 0.5-9%. The prevalence of impaired glucose regulation increased with age. Among individuals with diabetes, 65.6% were previously undiagnosed; this proportion was highest in the youngest age-group (82% among 45-year-old men vs. 63% among 60-year-old men, and 70% among 45-year-old women vs. 52% among 60-year-old women). Mean BMI, waist, HbA(1c), systolic blood pressure, diastolic blood pressure, and total cholesterol were significantly higher (P < 0.0001) in the individuals with impaired glucose regulation compared with individuals with normal glucose tolerance. CONCLUSIONS: This study revealed that the prevalence of type 2 diabetes is high and that still two out of three individuals are undiagnosed, indicating a need for more attention to the disease in society.  相似文献   
1000.
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