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991.
Using desorption/ionization techniques such as easy ambient sonic-spray ionization mass spectrometry (EASI-MS), it is possible to analyze documents of Brazilian vehicles for authenticity, providing a chemical profile directly from the surface of each document. A method for the detection of counterfeit documents is described, and the falsification procedure is elucidated. Forty authentic and counterfeit documents were analyzed by both positive and negative ion modes, EASI(±)-MS. EASI(+)-MS results identified the presence of (bis(2-ethylhexyl)phthalate plasticizer and of dihexadecyldimethylammonium biocide in both types of documents. For EASI(-)-MS results, the 4-octyloxybenzoic acid additive ([M + H](+): m/z 249) is present only in counterfeit documents. It was also found that counterfeit vehicle documents are produced via Laserjet printers. Desorption/ionization techniques, such as EASI-MS, offer therefore, an intelligent way to characterize the counterfeiting method.  相似文献   
992.
The history of the Department of Forensic Medicine of I.M. Sechenov First Moscow State Medical University is highlighted based on the results of the studies of the relevant literature data and archival materials. The authors lay special emphasis on the organization of the teaching process and research at different stages of the development of the Department, scientific and forensic medical activities of its leading specialists, materials obtained in the course of research, and the contribution to the development of forensic medicine made by outstanding scientists.  相似文献   
993.
The optimal conditions for the isolation of caffeine from human blood by means of acetone extraction are described with special reference to the peculiarities of extraction from aqueous solutions. The possibility of concentration and purification of caffeine from blood plasma using acetone and aceton-chlorophorm mixture (2:8) as the solvents is illustrated. In addition, purification by silica-gel thin layer chromatography is discussed. Thin layer chromatography, UV-spectrophotometry, and high performance liquid chromatography are considered as potential methods for the identification and quantitative determination of caffeine.  相似文献   
994.
This paper reports the results of analysis of the data obtained in experimental studies and practical expert assessments of body injuries inflicted by rubber balls for traumatic weapons. The causes accounting for the polymorphism of such injuries and the mechanisms of their development were elucidated by means of damage simulation taking into consideration the physical and dynamic properties of elastic ball-type destructive agents and the morphological structure of different anatomical regions of the human body. The results of the study may be of interest for differential diagnostics of gunshot lesions caused by elastic destructive agents.  相似文献   
995.
The method of residue extraction through electrostatic lifting provides a distinctive mode of performing ultra-trace analysis. These lifts provide a medium for analyte extraction via nanomanipulation-coupled to nanospray ionization-mass spectrometry (NSI-MS). This method of extraction can be coupled to Raman spectroscopy for supplemental verification of analytes using surface enhanced Raman scattering (SERS). The gold surface used for SERS provides an enhanced effect on peak signal intensity allowing ultra-trace amounts to be detected more effectively. The aim of this research is to utilize gold-coated films with electrostatic lifting in order to collect latent materials and analyze chemicals of interest contained in them via SERS.  相似文献   
996.
Abstract: Histopathologic features of New Mexico 2009 H1N1 fatalities have not been representative of those reported nationwide. We retrospectively reviewed medical records of all New Mexico 2009 pandemic influenza A (pH1N1) fatalities (n = 50). In cases in which autopsy was performed (n = 12), histologic sections and culture results were examined. In contrast to previously published studies, the majority of our fatalities did not have diffuse alveolar damage (DAD) (2/12; 16.7%). Common findings included pulmonary interstitial inflammation and edema, tracheobronchitis, and pneumonia. Two cases had significant extra‐pulmonary manifestations: myocarditis and cerebral edema with herniation. The majority had a rapid disease course: range from 1 to 12 days (median, 2 days), and Native Americans were disproportionately represented among fatalities. These findings suggest that New Mexico H1N1 fatalities generally did not survive long enough to develop the classic picture of DAD. Pathologists should be aware that H1N1 may cause extra‐pulmonary pathology and perform postmortem cultures and histologic sampling accordingly.  相似文献   
997.
Abstract: Conducted electrical weapons (CEWs) such as the TASER® M‐ and X‐series deliver short high‐voltage, low‐current energy pulses to temporarily paralyze a person by causing electrical interruption of the body’s normal energy pulses. Despite many scientific publications, which classify the health risks of an appropriate use of the TASER device as minor, there still is a continuous uncertainty about possible side effects with human application. Based on a literature search of the National Library of Medicine’s MEDLINE database’s PubMed system of current publications, the following article describes the mechanisms by which the device operates and discusses possible pathophysiological consequences. The majority of current human literature has not found evidence of clinical relevant pathophysiological effects during and after an exposure of professionally applied CEWs. However, to be able to exclude possible health risks, a medical checkup of people who have been exposed to CEWs is essential.  相似文献   
998.
Venlafaxine is a phenethylamine derivative widely prescribed for the treatment of depression which inhibits both serotonin and norepinephrine reuptake (SNRI). In treatment with antidepressants of patient with depression and other psychiatric disorders there is also increased risk of suicidal thought and behaviour. Several lethal intoxications involving venlafaxine usually among psychotic patients have been reported in the literature. Sample preparation is of the greatest significance for a successful toxicological analysis. The development of simple, effective and rapid extraction procedures of drugs from post-mortem biological samples is a challenge. Headspace-solid phase microextraction (HS-SPME) offers significant advantages such as simplicity, low cost, compatibility with analytical systems, automation and solvent-free extraction. The aim of our work was the optimization of a HS-SPME procedure for the determination of venlafaxine in post-mortem biological samples by gas chromatography (GC) with nitrogen-phosphorous detection (NPD). Venlafaxine was extracted on 100 μm Polydimethylsiloxone Coating-Red (PDMS) SPME fiber and determined by GC-NPD. Salt addition, extraction temperature, preheating and extraction time were optimized to enhance the recovery of the extraction from aqueous solution spiked with venlafaxine. Finally the developed procedure was applied to post-mortem biological samples of a fatally poisoned woman by venlafaxine. The drug was quantified in post-mortem blood gastric and oesophagus contents of the deceased woman. A simple and rapid procedure using HS-SPME was developed for sample preparation of venlafaxine in post-mortem biological samples prior to GC-NPD determination. Validation data was satisfactory, thus enabling application in the toxicological analysis of forensic samples.  相似文献   
999.
Clozapine is a uniquely effective antipsychotic, but is very toxic in clozapine-na?ve subjects. A 34-year-old male patient in a mental health facility, who was not prescribed clozapine, took 350 mg clozapine obtained from another patient at night. He was found dead the next morning. The presence of cardiomegaly related to obesity may have increased the risk of suffering an acute cardiac event after ingestion of clozapine. The medication prescribed to the patient was not thought to have contributed to the fatal outcome. Post mortem femoral blood clozapine and norclozapine concentrations were 0.48 and 0.20mg/L, respectively. By way of comparison, audit of 104,127 plasma samples (26,796 patients) assayed for therapeutic drug monitoring purposes 1993-2007, showed plasma clozapine 0.35 mg/L or more in 57.5% samples (8.4% 1mg/L or more). Those involved in the investigation of clozapine-associated deaths need to be aware that that death in an adult may occur after a single 'therapeutic' dose. A diagnosis of fatal clozapine poisoning cannot be made solely on the basis of a post mortem blood clozapine measurement.  相似文献   
1000.
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