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251.
The level of degradation of DNA as a means for determining the time of death has been proposed as a valid adjunct to the classic thanatochronologic methods. The twofold aim of this work was to determine which organ might reveal both a correlation between the percentage of degradation of the DNA and the time lapse since death, and would be easiest to sample and yield the most reproducible results even in technically unfavorable situations such as on-the-spot investigations at the scene of death. A comparison of the spleen, blood, and liver showed that hepatic tissue best meets these specific needs because it shows a virtually linear correlation between the time elapsed since death and the level of degradation of the DNA, and it can easily be sampled at the scene of death by use of a common biopsy needle.  相似文献   
252.
Murder-suicide in New Hampshire, 1995-2000   总被引:1,自引:0,他引:1  
Combined murder-suicide is defined as homicide(s) followed by the perpetrator's suicide within 1 week of the homicide(s). This phenomenon is observed worldwide with generally similar incidence rates. The authors report data from New Hampshire, a population distinguished from those in previous United States studies by its location, racial homogeneity, nonurban character, and low homicide rate. Sixteen murder-suicide events occurred in New Hampshire between October 1995 and October 2000. This represents an incidence of 0.26 per 100000 person-years, a rate similar to previously reported values. Murder-suicide events accounted for 14.7% of all homicides in the state, higher than previous studies but not unexpected in view of the state's lower homicide rate. Most perpetrators were male (94%), and most victims were female (88%), often in a spousal or consortial relationship. Firearms accounted for the majority of deaths. Various cofactors are examined, and a comparison of two recently proposed classification systems is discussed.  相似文献   
253.
Self-immolation is an uncommon method of suicide, and its occurrence in South Africa is thus far unknown. This study aimed to determine the prevalence of self-immolation deaths and to establish a profile of these cases and the circumstances under which this condition occurs. A 5-year (1996-2000) retrospective review at a mortuary in Durban, South Africa, was conducted. Data were obtained from the Department of Forensic Medicine, the Medical Research Council's National Injury Mortality Surveillance System, and police and hospital records. During the study period, there were 12339 nonnatural deaths, of which 696 (5.6%) were suicides. Self-immolation accounted for 69 (0.6%) of all nonnatural deaths and 69 (9.9%) of all suicides. The subjects had a mean age of 31.2 years and were predominantly female (76.8%) and black (81.2%). The mean burn surface area was 63.3%, and the mean injury severity score was 36.9. Accelerant use was documented in 53 (76.8%) of cases, and paraffin was preferred. All cases occurred indoors. The proportion of suicides due to self-immolation in our study is excessive when compared with international studies that report figures between 0.9% and 2.2% of suicides. Additional studies are necessary to further elucidate the reasons for this discrepancy.  相似文献   
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In this review we consider how Slovenia could consider tackling its high rate of suicide (overall 29 per 100,000, 46 in males, 13 in females). First, we consider the evidence for risk factors that may contribute to Slovenia's high rate of suicide. Second, we describe the interventions to try to reduce the impact of these factors and the evidence for such interventions. We categorize interventions in terms of their operation at either the population level or that of high-risk groups. However, it should be borne in mind that settings often assumed to provide access to population groups, such as general practice and schools, do not reach some people who are likely to be at high risk; for example those who have dropped out of school or who have been excluded from a GP's list. We focus particularly on those for high-risk groups, as a number of East-European countries with high suicide rates such as Slovenia, Hungary, and the Baltic republics are currently considering a shift toward more community-based mental health services. The provision of community mental health services in Slovenia would provide an opportunity to study their impact on the suicide rate. However, we conclude that their development should be accompanied by other initiatives operating at population levels. This multilevel approach acknowledges the complexity of the etiology of suicide, the impossibility of reaching all those at risk through services and the lack of strong evidence for any one intervention.  相似文献   
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The compound 1,2-indanedione was recently introduced in our laboratory as an operational reagent for developing latent fingerprints on porous surfaces. As part of the reagent implementation, a study was carried out in order to determine whether either of the two operational 1,2-indanediones formulations interferes with further DNA profiling. Both formulations are based on HFE7100 solvent. One is acidic and the other neutral. In a controlled experiment, known donors attached stamps to envelopes by licking them. The stamped envelopes were initially treated with either one indanedione formulation or the other, and DNA was then extracted for STR typing. No differences were observed between the STR profiles obtained from treated and untreated stamps and envelopes, indicating that 1,2-indanedione does not adversely affect the extraction and subsequent amplification of the STRs examined. However, preliminary results indicate that potential DNA analysis depends on the time interval between the indanedione treatment and DNA extraction as no DNA can be recovered six days following treatment. For this reason, it is strongly recommended to extract DNA from treated items of evidence as soon as possible after indanedione treatment.  相似文献   
259.
A 27-year-old man was carrying in his digestive tract 99 packages each containing about 10 g of a 86% cocaine powder. The courier died by acute cocaine intoxication due to inflation and rupture of four packages during a flight from Bogotá to Rome. At the autopsy, the external examination was unremarkable. The internal examination showed edema and generalized congestion of the organs. Toxicological analyses were performed by gas chromatography-mass spectrometry after solid phase extraction using Bond Elut Certify columns and derivatization with BSTFA/TMCS. High levels of cocaine and benzoylecgonine were found in blood (4.0 microg/mL and 17.0 microg/mL), urine (152.0 microg/mL and 512.0 microg/mL), bile (99.8 microg/mL and 54.0 microg/mL), vitreous humor (7.1 microg/mL and 5.8 microg/mL), brain (7.5 microg/mL and 3.5 microg/mL), and hair (55.5 ng/mg and 27.7 ng/mg). The presence of the cocaine and its metabolite in the hair suggested that the man was a cocaine user.  相似文献   
260.
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   
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