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241.
Each year over 3 million new chainsaws are sold in the United States. The operation of these newer saws combined with the millions of older chainsaws in circulation results in over 28,000 chainsaw-related injures annually. The majority of the injuries involve the hands and lower extremities with less than 10% involving injuries to the head and neck regions. Deaths while operating a chainsaw are extremely rare. The most common hazards associated with chainsaws are injuries caused by kickback, pushback, and pull-in. Kickback is the most common and poses the greatest hazard. Kickback occurs when the rotating chain is stopped suddenly by contact with a more solid area throwing the saw rapidly backward toward the operator. The cause of most injuries can be traced to improper use of the saw or poor judgment on part of the operator. We present two fatal chainsaw deaths; one with an older style saw, and the other with a modern type. In both cases the victims died from fatal injuries received to the neck region from a chainsaw kickback. The first case involved a 49-year-old white male operating an older style chainsaw with limited safety features. The second case involved a 38-year old white male who was operating a newer model chainsaw equipped with a low kickback chain in an unsafe manner.  相似文献   
242.
Colour marking cartridges as the FX ammunition (Simunition Europe, Brussels) are increasingly used by the police for realistic close range combat training. Conversion kits for service weapons of different manufacturers are available. The ballistic data of this ammunition is reported and experimentally verified. The risk of injury seems to be very low, if the recommended protective equipment is used. Small hematomas up to superficial lacerations are to be expected only in areas over a bony support. Shots to the unprotected eye will result in severe injuries.  相似文献   
243.
The eruption and mineralization of third molars are the main criteria for dental age estimation of living people involved in criminal proceedings. Since the development of third molars is usually completed by the age of 19 or 20 years, this feature cannot be used to ascertain whether a person has attained the forensically relevant age of 21 years. This study examined whether the DMFT index or the third molar DFT index could supply reliable information enabling conclusions to be drawn about whether a person has reached the age of 21. To this end, 650 conventional orthopantomograms of German subjects aged 18 to 30 years were evaluated. The DMF index variations considered were found to be unsuitable for determining whether a person is over 21 because they displayed a weak correlation with age and considerable individual scatter. A high indicative value can only be attributed to a third molar DFT index of 4, although this is rarely observed in the relevant age group. An X-ray examination of the medial clavicular epiphyseal cartilage is, therefore, strongly recommended when assessing whether a person has attained 21 years of age.  相似文献   
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Tests have determined that boots or shoes of individuals at a fire scene do not transport sufficient contaminants ("tracking") through the fire scene to produce a positive laboratory result for the presence of gasoline in a fire scene that was not present at the time of the fire. Questions about the validity of forensic laboratory results have been raised on the basis that low-level gasoline residues detected in the laboratory samples could have been the result of transporting the residue by footwear contaminated from the fire scene ("tracking"). The data collected in this study establish that "tracking" does not lead to false-positive laboratory results. Canines trained and experienced in the detection of trace ignitable liquid residues were also utilized in this study. The canine results confirmed that properly trained canines show a higher sensitivity than do standard ASTM laboratory techniques for fire debris analysis. In a few cases, canines responded to contamination, but laboratory testing (which is the definitive indicator) did not produce positive results.  相似文献   
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This study examined effects of clothing cues on children's identification accuracy from lineups. Four- to 14-year-olds (n = 228) saw 12 video clips of individuals, each wearing a distinctly colored shirt. After watching each clip children were presented with a target-present or target-absent photo lineup. Three clothing conditions were included. In 2 conditions all lineup members wore the same colored shirt; in the third, biased condition, the shirt color of only one individual matched that seen in the preceding clip (the target in target-present trials and the replacement in target-absent trials). Correct identifications of the target in target-present trials were most frequent in the biased condition, whereas in target-absent trials the biased condition led to more false identifications of the target replacement. Older children were more accurate than younger children, both in choosing the target from target-present lineups and rejecting target-absent lineups. These findings suggest that a simple clothing cue such as shirt color can have a significant impact on children's lineup identification accuracy.  相似文献   
249.
A cardiac concussion is caused by a sudden, nonpenetrating, localized impact to the chest that is theorized to result in almost simultaneous sudden death from a disruption to the conductive system. The detailed external/internal forensic examination of the body reveals no evidence of structural, pathologic, or histologic signs of trauma to the heart. A cardiac concussion is a rare and often overlooked cause of sudden death. This type of sudden death is typically seen among younger individuals participating in sports involving projectiles and, to a lesser degree, where collisions occur. Cardiac concussions are clinically, pathologically, and chemically different from a cardiac contusion. The objective of this paper will be to define cardiac concussion, differentiate between cardiac concussion and cardiac contusion, and describe the clinical and pathologic features of a 32-year-old white male who died of a cardiac concussion following a collision with a catcher during a softball game. The civil ramification of incorrectly diagnosing the manner of death in cases of death involving a cardiac concussion will also be addressed.  相似文献   
250.
A 70-year-old male patient with a 23-year-old history of right lower lung lobectomy for primary pulmonary adenocarcinoma (T1 N0 M0) presented with recurrent bronchopneumonia and purulent sputum. Pleural callus, lung abscess, bronchopleural fistula, and stitch granulomas were confirmed by chest x-ray, computed tomography scan, and bronchoscopy in the background of his complaints. An attempt to remove the bronchial purulent discharge and tissue sampling was made by using a flexible bronchoscope. The area of the lower trachea suddenly became clogged during bronchoscopic removal of the suspected piece of tissue (which later turned out to be organizing surgical gauze). The resuscitation following ventricular fibrillation failed to save the patient's life. The forensic postmortem examination confirmed the position of the foreign body extending from the abscess cavity, crossing the midline at carina and obstructing the lower trachea. This foreign body was a remnant of the surgical gauze left behind during a thoracic surgery 23 years ago.  相似文献   
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