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891.
892.
Electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry have been used to examine evidence in a sexual assault investigation. Because condoms are being used increasingly by sexual assailants and some condom brands include the spermicide nonoxynol-9 (nonylphenoxy polyethoxyethanol) in the lubricant formulation, the recovery, and identification of nonoxynol-9 from evidence items may assist in proving corpus delicti. A method was developed for the recovery of nonoxynol-9 from internal vaginal swabs and for its identification by reverse phase liquid chromatography/electrospray ionization mass spectrometry (LC ESI-MS), nanoelectrospray ionization (nanoESI) mass spectrometry, and high resolution MALDI Fourier transform mass spectrometry (MALDI-FTMS). The method was tested on extracts from precoitus, immediate postcoitus, and four-hours postcoitus vaginal swabs provided by a volunteer whose partner does not normally use condoms, but for this trial used a condom having a water-soluble gel-type lubricant that includes 5% nonoxynol-9 in its formulation. Subsequently, LC ESI-MS was used to identify traces of nonoxynol-9 from the internal vaginal swab of a victim of a sexual assault.  相似文献   
893.
In order to establish an animal model for entomotoxicological studies, the kinetics of morphine elimination from blood after a single intravenous injection of morphine and the concentration of morphine in tissues following a continuous perfusion were studied. The aim of these experiments was to obtain controlled morphine tissue concentrations similar to those encountered in fatal human heroin overdoses. These tissues can be used as a food source for developing fly larvae in entomotoxicological studies. In the single injection experiment, seven rabbits were administered 1 or 2 mg/kg body weight of morphine chlorhydrate via the main ear artery. Blood samples of 200 microL were removed regularly via a catheter. Morphine concentration was determined using RIA techniques. Morphine was found to be first rapidly distributed and then slowly eliminated, following a two-exponential equation. Elimination of morphine from blood can be described as a two-compartment model. Constants of the equation were determined using the Kaleidagraph program. Using those constants, the main pharmacokinetics parameters were calculated. Results of these parameters showed the following: clearance from 13.3 to 16.2 L.h.1, half-life of the distribution phase from 0.6 to 0.9 min, and half-life of the elimination phase from 21 to 26 min. These results were used to calculate the rate of perfusion of morphine for rabbits to obtain desired, controlled, and constant concentrations of morphine in tissues. In the second experiment, three rabbits received a perfusion of morphine intravascularly at a rate of 2 mg/kg/h for a period of 3 h. These rabbits were sacrificed and analyses performed on several abdominal and thoracic organs. Results showed that the concentrations of morphine differed according to the organ analyzed, but were reproducible for organs between animals. These concentrations were similar to those normally encountered in cases of human death due to heroin overdoses.  相似文献   
894.
A study was undertaken to develop demographic, toxicologic, and pathological profiles of methamphetamine-related deaths. Anatomic and toxicologic findings in 413 deaths where methamphetamine was detected were compared with findings in a control group of 114 drug-free trauma victims. The number of cases per year did not change significantly over the course of the study. Mean age was 36.8 years, but 11% were over the age of 50. Decedents were overwhelmingly male (85.2%) and Caucasian (75%). Blood concentrations of methamphetamine and amphetamine were indistinguishable in cases where methamphetamine was related to the cause of death (MR) and cases where it was not (non-MR) (2.08 vs. 1.78 mg/L, p = 0.65, and 0.217 vs. 0.19 mg/L, p = 0.82). Coronary artery disease, ranging from minimal to severe multivessel, was identified in 79 of the 413 drug users, but in only six of the 114 drug-free controls (p = 0.0004), and MR decedents had enlarged hearts compared with controls. There were also ten cases of subarachnoid and intracranial hemorrhage in the MR group. Abnormalities of the liver (34%) and lungs (24.7%) were frequent. In 65% of these cases, death was due to accidental methamphetamine toxicity. In the remaining cases, methamphetamine was an incidental finding. We conclude that, in our jurisdiction, neither the rate of detection nor the number of methamphetamine deaths has increased significantly in the past 13 years. Decedents are almost all Caucasian males, and many were approaching middle-age. Methamphetamine use is strongly associated with coronary artery disease and with subarachnoid hemorrhage.  相似文献   
895.
No reliable data are available on cases of lethal child abuse (by active force) in the area of the former German Democratic Republic. In a multicenter study we therefore examined the police and court records for such cases occurring in the period 1 January 1985 to 2 October 1990 in the entire area of the former German Democratic Republic. RESULTS: The study center received information on 39 cases of lethal child abuse which correspond to approximately 7 cases per year. However, a low percentage of undetected crimes which cannot be determined more precisely has to be taken into consideration. Almost 40% of the victims were younger than 1 year, 73% of the victims showed indications of repeated ill-treatment. The effects caused by using direct blunt forces, against the head in particular, were by far the most frequent causes of death. The male contact person (the victim's father, brother or stepfather as well as the life companion of the child's mother in particular) killed the child in most of the cases. As far as it is known, 37% of the male/female offenders suffered from chronic alcoholism; 32% of the male/female offenders were under the influence of alcohol when the crime happened. 83% of the male/female offenders who were found guilty made a confession shortly after the crime had happened or during the interrogations. Almost all the male/female offenders were sentenced to prison (the duration of the imprisonment varied between one year and for life). Due to the considerably lower section rate compared to the one in the German Democratic Republic, it is to fear that each second fatal child abuse is not detected in the new federal states.  相似文献   
896.
No reliable data are available on cases of lethal child abuse (by active force) in the area of Federal Republic of Germany prior to reunification (the former West Germany). In a multicenter study we therefore examined the police and court records for such cases occurring in the period 1 January 1985 to 2 October 1990 in nearly the entire area of Federal Republic of Germany. RESULTS: The study center received information on 58 cases of lethal child abuse. Extrapolated to all institutes of legal medicine, this corresponds to 62 cases in all of West Germany in the period studied. An approximately equal number of unreported cases should be added to this figure. Including unreported cases, at least 20 cases of lethal child abuse occurred per year; thus only one in every two cases ever came to light. Almost two thirds of the victims were younger than one year old. At autopsy 59% exhibited signs of repeated abuse at autopsy. By far the most common cause of death was direct impact from a blunt object, usually to the head. Mostly, the male person to whom the victim relates most closely (father, stepfather, partner of the mother) has killed the child. Twenty-one of the 74 persons charged saw the charges against them dropped or were acquitted due to lack of evidence; 51 received sentences ranging from one year probation to life. In the remaining two cases the outcome of the trial was unknown. Signs of abuse were readily apparent at autopsy in almost all cases. The high number of unreported cases underscores the need to educate medical students and practicing physicians to be on the look-out for signs of abuse and argues for an increase in the rate of autopsy.  相似文献   
897.
This article describes the application of solid-phase microextraction (SPME) to the recovery of manufacturing by-products and impurities from an illicit drug seizure. The preparation chosen for examination using this technique contained 4-methoxyamphetamine, an hallucinogenic amphetamine that has been encountered frequently in South Australia. Compounds found in the PMA preparation included 4-methoxyphenol, 4-methoxybenzaldehyde, 4-methoxyphenyl-2-propanone, 4-methoxyphenyl-2-propanol, 4-methoxyphenyl-propene, and (tentatively) 4-methyl-5-(4'-methoxyphenyl) pyrimidine. The presence of these compounds suggests that the active drug was prepared from 4-methoxybenzaldehyde via 4-methoxyphenyl-2-propanone using a Leuckardt reductive amination. In this instance, SPME was found to be a simple, rapid, and non-destructive recovery technique that gave results complementary to those provided by conventional liquid-liquid extraction. There is an indication that SPME might find application in profiling of illicit drugs.  相似文献   
898.
Beer consumption is commonly an issue in a medico-legal setting, requiring estimates either of a likely blood alcohol concentration (BAC) for a given pattern of consumption or vice versa. Four hundred and four beers and malt beverages available for sale in the State of Washington were tested by gas chromatography for their alcohol content. Considerable variability in the alcoholic strength was found, even within the same class. Overall the range of concentrations was 2.92%v/v to 15.66%v/v. The mean alcohol concentration for ales was 5.51%v/v (SD 1.23%v/v), and for lagers, 5.32% (SD 1.43%v/v). Some specialty brews had characteristically higher or lower mean concentrations: ice beers 6.07%v/v, malt liquor 7.23%v/v, light beer 4.13%v/v, seasonal ales 6.30%v/v. Six brands of lager and four light beers account for the majority of all beer sales in the United States, and the mean alcohol concentration for these products was measured as 4.73%v/v and 4.10%v/v respectively. Few of the beers (17%) were labeled with respect to alcohol content, and in some cases, there was a significant disparity between the concentration listed on the label, and the measured alcohol concentration. Toxicologists need to exercise caution when performing Widmark type calculations, using all available information to select the most appropriate estimate for alcoholic strength of a beer or malt beverage.  相似文献   
899.
Histological analysis of the viscera in experimental poisoning with psilocybin-containing mushrooms showed nonspecific changes in all examined organs, presenting as expressed hemocirculatory disorders and intracellular dystrophy. Quantitative histochemical analysis showed appreciable shifts in the activities of enzymes involved in the cytoplasmic and mitochondrial redox processes and of specific enzymes involved in nerve tissue metabolism. This may reflect some features in the direct effects of narcotic alkaloids contained in psilocybin-producing mushrooms.  相似文献   
900.
The index of lethal poisoning with ethyl alcohol and its surrogates in Russia remains one of the highest in the world. It is explained by high alcohol consumption in Russia (about 15 liters of pure alcohol per capita annually), consumption of mainly strong beverages (about 80%), extensive sales of adulterated strong alcoholic beverages (more than 25%), virtually no preventive work in the population, and other causes. The index of lethal poisoning with alcohol and its surrogates in the country and its regions is one of the most important parameters in evaluation of the socioeconomic well-being of the population.  相似文献   
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