全文获取类型
收费全文 | 4612篇 |
免费 | 46篇 |
专业分类
各国政治 | 173篇 |
工人农民 | 33篇 |
世界政治 | 565篇 |
外交国际关系 | 479篇 |
法律 | 2698篇 |
中国共产党 | 83篇 |
中国政治 | 236篇 |
政治理论 | 296篇 |
综合类 | 95篇 |
出版年
2021年 | 25篇 |
2018年 | 22篇 |
2016年 | 19篇 |
2015年 | 22篇 |
2014年 | 109篇 |
2013年 | 27篇 |
2012年 | 304篇 |
2011年 | 280篇 |
2010年 | 99篇 |
2009年 | 106篇 |
2008年 | 261篇 |
2007年 | 303篇 |
2006年 | 300篇 |
2005年 | 270篇 |
2004年 | 270篇 |
2003年 | 270篇 |
2002年 | 254篇 |
2001年 | 200篇 |
2000年 | 209篇 |
1999年 | 93篇 |
1998年 | 47篇 |
1997年 | 35篇 |
1996年 | 44篇 |
1995年 | 32篇 |
1994年 | 67篇 |
1993年 | 40篇 |
1992年 | 31篇 |
1991年 | 61篇 |
1990年 | 30篇 |
1989年 | 34篇 |
1988年 | 111篇 |
1987年 | 28篇 |
1986年 | 33篇 |
1985年 | 39篇 |
1984年 | 41篇 |
1983年 | 33篇 |
1982年 | 22篇 |
1981年 | 36篇 |
1980年 | 37篇 |
1979年 | 40篇 |
1978年 | 16篇 |
1977年 | 43篇 |
1976年 | 34篇 |
1973年 | 18篇 |
1964年 | 28篇 |
1963年 | 25篇 |
1962年 | 40篇 |
1961年 | 18篇 |
1960年 | 23篇 |
1959年 | 30篇 |
排序方式: 共有4658条查询结果,搜索用时 15 毫秒
211.
Salzberger LA Cavuoti D Barnard J 《The American journal of forensic medicine and pathology》2002,23(4):382-385
Salmonellae most commonly cause uncomplicated cases of gastroenteritis but have a predilection for damaged blood vessels, especially those damaged by atherosclerosis. The abdominal aorta is most frequently affected. The most serious complication of aortitis is mycotic aneurysm formation with subsequent rupture. The authors present the case of a 61-year-old man who was found unresponsive at home 3 days after discharge from the hospital for treatment of gastroenteritis with bacteremia. Postmortem examination revealed a ruptured mycotic aneurysm with a large retroperitoneal hematoma. Numerous gram-negative rods were embedded in the wall of the aorta and surrounding inflammatory infiltrate, compatible with the patient's previously isolated. Whereas abdominal aortic aneurysm rupture is most commonly associated with atherosclerosis, the isolation of from blood cultures, coupled with radiographic evidence of gas surrounding the aorta, should raise the suspicion of infectious aortitis. Whereas fatal rupture of an aortic aneurysm secondary to atherosclerosis alone or in conjunction with aortitis will not have an impact on the manner of death, infections are reportable and thus have public health implications. 相似文献
212.
目的构建重组pET28a-EDA-EDB质粒,制备重组纤维连接蛋白EDA-EDB融合蛋白。方法采用基因重组技术,将EDA、EDB基因片段连接,再将该重组基因插入pET28a表达载体,表达重组融合EDA-EDB蛋白后,利用6×His/Ni-NTA纯化系统进行纯化,免疫印迹法检测。结果成功连接EDA、EDB基因片段,重组pET28a-EDA-EDB质粒;在大肠杆菌BL21(DE3)中高度表达重组蛋白,获得较纯的重组蛋白,免疫印迹法证实为FN的组分。结论EDA-EDB重组蛋白能采用pET系统在大肠杆菌中表达,并可通过6×His/Ni-NTA纯化系统进行纯化而获得免疫原。 相似文献
213.
214.
Rates of deliberate self-harm have been reported to be higher among South Asians, especially women, in the UK. Two studies collected information on inception rates of deliberate self-harm in the UK and reported that rates of attempted suicide are much higher among South Asian women especially those aged 18-24. These rates are associated with high rates of cultural alienation and previous attempts. The implications of cultural conflict are discussed in this context. In addition, a hypothetical model of interrelationship of factors for both adults and adolescents is described. 相似文献
215.
216.
217.
The authors report on the case of a 18-year-old student who died suddenly and unexpectedly of a pericardial tamponade after perforated ulcer-polypous endocarditis of the aortic valve. The detection of aerococcus urinae--which usually causes urinary tract infection--on the inflamed aortic valve demonstrates an unusual pathogenetic chain linking complexes of findings in the urogenital system and the heart. 相似文献
218.
The glucuronide conjugation is a minor pathway of ethanol metabolism. The determination of ethyl glucuronide (EG) in serum and urine has gained importance in forensic and other legal decisions. To prospectively calculate the serum concentration of this non-oxidative ethanol metabolite, the computer program developed includes a parameter fitting routine. Multiple ethanol doses can be handled.The mathematical modeling was based on the following assumptions and simplifications, respectively. A single enzyme system is responsible for ethanol conjugation at one distinct site; the distribution of EG into the systemic circulation is delayed; the elimination of EG follows first-order kinetics.The concentration of EG was calculated using three kinetic parameters: a rate constant for the first-order formation of EG from serum ethanol, a transfer constant for an obstructed transfer of EG from the formation site (FS) into the central compartment (CC) and an exponential elimination constant.The program was applied to the data collected from 21 drinking experiments. The fitting algorithm optimized the three kinetic parameters, until the sum of concentration error squares of the data points was minimized. The means+/-standard deviation of the rate constant for the first-order formation of EG from serum ethanol was 0.0011+/-0.0006 h(-1), the transfer constant for an obstructed transfer of EG from the FS into the CC was 0.43+/-0.1996 h(-1) and the exponential elimination constant was 3.0+/-1.45 h(-1).Using the range of these parameters, it is now possible to calculate minimum and maximum serum concentrations of EG based on ethanol doses and drinking times. The comparison of calculated and measured concentrations can prove the plausibility of an alleged ethanol consumption. This can be crucial when the serum ethanol concentration (SEC) itself is not meaningful. 相似文献
219.
An unusual case of driving under the influence of the volatile anaesthetic enflurane is reported. A markedly affected anaesthetist was sniffing at an enflurane-moistened handkerchief before he crashed into a lorry at a red traffic light. In the blood sample enflurane (2.92 mg/l) as well as diclofenac (0.28 mg/l) and 4-aminophenazone (24.4 mg/l) were found. The way of driving and the accident and the deficiency symptoms could be explained by the central suppressing effects of enflurane. The physician was considered as impaired and not suitable to drive at the time of the incidence. 相似文献
220.
Glycated hemoglobin (HbA(1c)) has been demonstrated to be a useful marker for long-term glucose control in diabetes. This parameter characterizes each non-enzymatic fixation of glucose on hemoglobin. It is a useful test in addition to periodic glycemia controls since it reflects the mean glycemia of the past 60 days. We studied the conservation of HbA(1c) at 4 degrees C as a function of time with different anti-coagulants and preservatives (3, 6 months, 1 year). A total of 106 tests were performed using the high performance liquid chromatography (HPLC) method dedicated to the semi-automatic analysis of HbA(1c) (Bio-Rad) and we applied the method in forensic cases. Conservation at 4 degrees C was good for as long as 3 months in blood samples collected with fluoride and 6 months in samples collected in a dry or in a heparinized tube. In non-diabetic subjects, HbA(1c) reference values obtained from forensic samples were identical to those of living controls (3.5-6.25% of total hemoglobin). All positive HbA(1c) results were confirmed by a medical evaluation. This method was successfully applied to five forensic cases. In cases of increased acetonemia, acetone or isopropanol are easily measured. However, in some unexplained post-mortem circumstances, increased HbA(1c) permits to differentiate alcoholic or starvation ketoacidosis from the diabetic cases. Glycated hemoglobin should, therefore, be considered the forensic marker of choice in the post-mortem diagnosis of a diabetic disorder and demonstrates its usefulness in post-mortem validation. 相似文献