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   1951篇
  免费   35篇
各国政治   42篇
工人农民   16篇
世界政治   297篇
外交国际关系   92篇
法律   1301篇
中国共产党   24篇
中国政治   66篇
政治理论   117篇
综合类   31篇
  2019年   3篇
  2018年   3篇
  2015年   2篇
  2014年   5篇
  2013年   4篇
  2012年   125篇
  2011年   140篇
  2010年   42篇
  2009年   27篇
  2008年   115篇
  2007年   144篇
  2006年   185篇
  2005年   168篇
  2004年   163篇
  2003年   135篇
  2002年   120篇
  2001年   99篇
  2000年   101篇
  1999年   51篇
  1998年   22篇
  1997年   10篇
  1996年   14篇
  1995年   20篇
  1994年   31篇
  1993年   19篇
  1992年   15篇
  1991年   13篇
  1990年   8篇
  1989年   10篇
  1988年   16篇
  1987年   13篇
  1986年   12篇
  1985年   9篇
  1984年   9篇
  1983年   19篇
  1982年   10篇
  1981年   14篇
  1980年   19篇
  1979年   13篇
  1978年   5篇
  1977年   6篇
  1975年   2篇
  1974年   4篇
  1964年   3篇
  1963年   5篇
  1962年   8篇
  1961年   5篇
  1960年   3篇
  1959年   4篇
  1956年   2篇
排序方式: 共有1986条查询结果,搜索用时 15 毫秒
991.
A case of malignant hyperthermia (mh) in a 27-year-old man is described. In a first anaesthesia using isoflurane and succinylcholine, the end-tidal CO(2) rose from 39 to 49 mmHg 2.75 h post-intubation and the body temperature rose to 39.8 degrees C 14 h post-intubation but was normal again the next day. In a second anaesthesia using the same medication, the maximal end-tidal CO(2) was 44 mmHg and the body temperature rose to 39 degrees C after 9 h. After 4 days, the fever rose to 40 degrees C, and to 42 degrees C when death occurred 10 days after the second anaesthesia. Masseter spasms or muscle rigidity were never present. According to the death certificate, death was due to multi-organ failure from sepsis. At autopsy, the skeletal muscles were pale and oedematous. Histology demonstrated focal necroses in the skeletal muscles, shock kidneys with myoglobin excretion and myoglobin clots in small blood vessels of the lungs. Hence, the postmortem diagnosis "malignant hyperthermia" was established but accusations of medical maltreatment were rejected because of the atypical and protracted clinical course and because uncharacteristic signs of malignant hyperthermia were attributable to the clinically suspected sepsis.  相似文献   
992.
尿中MDMA及其代谢物的GC和GC/MS分析   总被引:3,自引:0,他引:3  
Shen M  Yan W  Shen B  Xiang P  Huang Z  Liu W  Bo J 《法医学杂志》1998,14(1):10-11,24
考察MDMA在人体内的代谢以及建立尿中MDMA和体内主要代谢物MDA的分析方法。尿样水解后经液-液提取处理,用GC/MS(EI、PCI)和GC/FID法分析。人摄入MDMA后尿中MDA和原体MDMA比约为0.10~0.14。GC/MS/SIM和GC/FID法的最低检出限为2ng/ml和50ng/ml,回收率大于85%,变异系数小于10%。该法简便快速、灵敏度高、结果可靠,可用于MDMA滥用者的尿样鉴定。MDA/MDMA浓度比可作为评判毒分结果的参考指标。  相似文献   
993.
Allele frequencies for the nine STR loci included in the AmpFlSTR Profiler kit were determined in a Thai population of 100 unrelated individuals.  相似文献   
994.
Operational details and optimisation of the colloidal gold or multimetal deposition technique (MMD) for the detection of latent fingermarks on non porous and porous surfaces demonstrate the power of the method. Control of particulate size, pH, reagent, handling are shown to be essential. A difficult case example illustrates the potential of MMD.  相似文献   
995.
The locus D8S320 is an STR system first described in 1993 as a simple (AAAG) repeat. Sequencing data revealed that the D8S320 locus is a complex STR system consisting of (AAAG)- and (AAAC)-repeat units. A total of 22 different alleles were found in a population survey of 210 unrelated individuals from the Rhine area with frequencies ranging from <0.01 to 0.198. The population data revealed the existence of variant alleles differing by 1 and 2bp from the consensus allele. Due to the complex repeat structure consisting of three variable regions and one constant region, electrophoresis under denaturing conditions is strongly recommended. The statistical values were calculated to be 0.89 (observed heterozygosity rate), 0.96 (discrimination index) and 0.71 (mean exclusion chance). No deviation from Hardy-Weinberg equilibrium (HWE) was observed.  相似文献   
996.
997.
A 7-month-old boy was found lifeless in his bed by his grandfather. Near the mouth there were some blood and chyme on the bedlinen. His mother reported a chill during the last 8 days. Autopsy revealed multiple petechia under the capsule of the thymus, subepicardially and subpleurally, the cause of death was tentative supposed to be a sudden infant death. Histologically parts of the myocardium showed a lympho-monocytic myocarditis according to the DALLAS-criteria. Immunohistological investigations demonstrated an enhanced expression of MHC class II antigens, an increased number of leucocytes as well as T-lymphocytes. In situ hybridization and immunohistochemistry revealed myocardial enterovirus infection. Considering that there were regions in the myocardium without the traditional findings of myocardial necrosis and inflammation but with distinct expression of the above mentioned immunohistologic markers, immunohistological investigations turn out to be an appropriate tool to examine infant fatalities with uncertain cause of death for early stages of myocarditis.  相似文献   
998.
Was the pedestrian hit in an erect position before being run over?   总被引:1,自引:0,他引:1  
If a pedestrian was run over by a car, the question can arise whether there was a preceding collision while the pedestrian was in an erect position. From a total of 53 selected autopsy reports, the findings associated with accidents known to involve running over in isolation (n=32) were compared to findings associated with a combined mechanism of a primary impact in an erect position and subsequent running over (n=21). Findings exclusively present in the combined group were wedge-shaped bone fractures ("Messerer"-wedges, 38%), glass fragment injuries (24%), traumatic amputations (10%), traces of car paint on the lower extremities (50%) and abrasions of the shoe soles (17%). These findings can be considered specific for a primary impact in an erect position. Fractures of the cervical and lumbar spine were present in the combined group in 33 and 17%, respectively. In contrast, in the run over group, there was only one case of fracture of the cervical and one of the lumbar spine and both cases involved direct contact with a car wheel. Fractures of the cervical and lumbar spine are, therefore, very indicative for a primary impact. "Bumper injuries", sacroiliac dislocations and fractures of the thoracic spine were approximately 2.5 times more common in the combined group than in the run over group. In the vast majority of cases, a clear differentiation between the two groups is, therefore, possible on the basis of the autopsy findings. This is especially relevant if an inspection of the car cannot be performed after a hit-and-run accident, which occurred in 26% of the cases in this study. In addition, the blood alcohol levels were higher in the run over group (mean=2.14g/l) as compared to the combined group (mean=1.53g/l).  相似文献   
999.
Human identification and forensic criminal casework may involve DNA profiling of decomposed material. Somatic microsatellite (STR) instability may lead to false exclusions and theoretically to false inclusions, both in criminal cases and in human identification. Hence, the somatic and postmortal stability of the actual sequences is crucial to the reliability of such analyses. Somatic STR stability in human tissues has been documented in small series only and the effect of postmortal tissue decomposition on microsatellite stability remains to be elucidated. On this basis, we have systematically searched for somatic STR mutations in 26 deceased humans without signs of decomposition at autopsy and 25 autopsy cases with obvious signs of postmortal decomposition. A blood sample and six tissue samples were collected from each case.Seven STRs were chosen for study, the tetranucleotides HUMVWA31/A, HUMTH01, HUMF13A1, and HUMFES/FPS, and the hyperpolymorphic markers HUMAPOAI1, D11S554 and HUMACTBP2. Denaturing gel electrophoresis was performed on an ABD Prism 377 gene sequencer with Genescan 672 software (Applied Biosystems, Inc.).The bone DNA profile of each case was chosen as the standard DNA profile. All cases gave profiles from additional tissues. By intraindividual comparison of DNA profiles in the cases without signs of degradation we find that the short repetitive sequences under study are stable, that is without evidence of somatic mutations. The cases with varying degree of decomposition display postmortal microsatellite stability, we detect no somatic mutations or other possible postmortal changes that could lead to between-organ non-matches.In conclusion, PCR-based STR analyses are suitable in human identification and forensic casework dealing with different tissues, even when the substrate is heavily decomposed.  相似文献   
1000.
Tinuvin 770/bis(2,2,6,6-tetramethyl-4-piperidinyl)sebacate is a worldwide used light stabilizer for plastic materials like polyolefins. Tinuvin 770 is a biologically active component of polypropylene tubes. Glossmann and his study group managed to extract this compound by aqueous or organic solvents from laboratory plastic tubes, and propose that Tinuvin 770 is a potent blocker of L-type Ca(2+)-channel through the phenylalkylamine and benzothiazepine-selective drug binding domains of the alpha(1) subunit of the receptor [Proc. Natl. Acad. Sci. U.S.A. 90 (1993) 9523].We examined the direct morphological effect of Tinuvin 770 in give 25nmol, 0, 30, 60, 120 minute exposure time in isolated cardiomyocytes from adult rats. Incubation of myocytes with Tinuvin resulted in a progressive decline of rod-shaped and viable cells. It was accompanied by an increase in number of hypercontracted myocytes with microbleb formation compared to control and depletion of ATP level.In summary, our results demonstrate that plasma membrane damage and hypercontraction are manifestations of Tinuvin-induced injury of isolated cardiomyocytes.  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