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141.
RUS-CHN图谱骨龄评价法用于推侧青少年年龄   总被引:3,自引:1,他引:2  
目的探讨RUS-CHN(RC)图谱评价法用于13~18岁青少年年龄推侧的应用价值。方法4 424名(男2 272,女2 152)13~18岁正常城市汉族青少年,以简化RUS-CHN法建立手腕骨发育等级图谱。另以1 048名(男530,女518)13~18岁青少年为检验样本,比较不同方法骨龄与生活年龄的差异。结果RUS-CHN图谱法可仅评价桡骨、尺骨远端和第III指的4块掌指骨骺。检验样本中男14~17岁、女13~16岁年龄组,RC图谱法骨龄与生活年龄之间的差异均无统计学显著性(W ilcoxon符号秩和检验,P>0.05),对男18岁、女17岁组出现显著性差异的可能原因进行了讨论。结论RUS-CHN图谱法骨龄适用于男13~18岁、女13~17岁青少年的年龄推测。  相似文献   
142.
Caspase3和iNOS在人挫伤脑组织中的时序性表达   总被引:1,自引:0,他引:1  
目的研究人脑挫伤后不同时间半胱氨酸天冬氨酸蛋白酶3(caspase3)和诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)表达的变化,为法医实践中脑损伤时间的推断提供依据。方法选择30例因颅脑损伤死亡案例为损伤组,5例非颅脑损伤急死的案例为对照组,应用免疫组织化学和图像分析技术,分别于死亡后2h、4~8h、10~14h、1~2d、3~5d及8~11d检测脑组织标本中caspase3和iNOS的变化规律。结果经统计学分析:(1)caspase3阳性细胞表达在伤后2h以内组开始升高,与对照组相比差异有统计学意义(P〈0.05),1~2d组表达强度增高,3~5d组仍见高表达(P〈0.05),以后逐渐下降。(2)iNOS阳性细胞表达在2h以内组与对照组比较差异无统计学意义(P〉0.05),伤后4~8h开始升高(P〈0.05),1~2d组表达强度最高,以后逐渐下降,伤后8~11d仍有弱表达(P〈0.05)。结论caspase3和iNOS的表达可能成为实际检案中脑损伤时间推断的有效依据。  相似文献   
143.
目的研究Demirjian法推断上海汉族青少年生活年龄的适用性。方法收集上海市第九人民医院符合纳入标准的年龄在11~20周岁的汉族青少年口腔曲面全景片501例.其中男性168例.女性333例。按照Demirjian法进行牙龄推断,并对生活年龄与Demirjian法推断的牙龄进行配对t检验:通过单因素数学模型探索两者之间的关系。结果直接应用Demirjian方法推断上海汉族青少年牙龄时.其推断的牙龄与实际生活年龄之间存在差异。通过建立牙龄推断的单因素数学模型。并将其推断的年龄与实际生活年龄进行配对t检验,结果显示男性12~16周岁(不含16周岁)、女性13~14周岁(不含14周岁)和15~17周岁(不合17周岁)年龄段无统计学意义(P〉0.05),并且有81.04%的样本推断误差小于1岁。结论本研究有望成为推断上海地区汉族青少年生活年龄的有效方法,但不适合17周岁以上青少年人群。  相似文献   
144.
目的应用荧光原位杂交(fluorescence in situ hybridization,FISH)技术检测大鼠骨骼肌挫伤后细胞间黏附分子-1(intercellular adhesion molecular—1,ICAM-1)mRNA表达。分析其与挫伤时间的关系。方法建立大鼠骨骼肌挫伤模型.分别取伤后0.5、1、6、12、18、24、30h及对照组检材。检材冰冻切片后进行FISH.激光共聚焦显微镜观察。结果大鼠骨骼肌挫伤后ICAM-1mRNA的表达6h达到峰值,18h下降至对照组的3.46倍.随后继续升高。结论大鼠骨骼肌挫伤后30h内ICAM—1mRNA的表达有一定的时间规律性.可望作为推断骨骼肌早期损伤时间的指标之一。  相似文献   
145.
目的观察小鼠皮肤切创愈合过程中成纤维细胞激活蛋白(fibroblast activation protein,FAP)和α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)表达的变化规律。方法应用免疫组织化学和West-ern印迹法检测小鼠皮肤切创后各个时间段FAP和α-SMA表达情况。结果免疫组化结果显示FAP与α-SMA在正常对照组及伤后1h组小鼠皮肤弱表达,伤后6h阳性细胞率开始升高,伤后5dFAP阳性细胞率达高峰,伤后3dα-SMA阳性细胞率达高峰,伤后14dFAP与α-SMA恢复至与对照组相同。Western印迹法检测显示FAP和α-SMA从1d起各个时间段均有表达,其中5d为FAP的表达高峰,3d为α-SMA的表达高峰。结论FAP可作为法医学皮肤切创形成时间的推断指标,α-SMA可作为损伤修复中后期的推断指标,FAP与α-SMA联合使用有望成为推断皮肤损伤时间的有效指标。  相似文献   
146.
论犯罪低龄化与刑事责任年龄制度改革   总被引:1,自引:0,他引:1  
追溯中国古代刑事责任年龄的立法沿革,研究国外及港澳台地区刑事责任年龄的阶段划分,对于更好地改革完善我国刑事责任年龄制度有着重要的借鉴意义。当前,针对未成年人犯罪低龄化趋势,适当降低刑事责任年龄既十分必要,又不失为一种有效的对策。  相似文献   
147.
Current standards for age at death estimation from the pelvis are based on Americans of European and African ancestry. Our limited understanding of population variability hampers our efforts to apply these techniques to the various skeletal populations around the world, especially in global forensic contexts. However, documented skeletal samples are rare, limiting our ability to test our techniques. This study tested the Suchey-Brooks pubic symphysis aging method and the auricular surface method originally developed by Lovejoy et al. on a large sample (n = 404) of known sex and age from the Sassari Collection, housed at the Museum of Anthropology at the University of Bologna, Italy. The results indicate that for both methods, bias and inaccuracy increased with age and actual age tended to be underestimated over the age of 40. The auricular surface method performed slightly better, exhibiting slightly lower levels of bias and inaccuracy, especially for males.  相似文献   
148.
Two main approaches can be used for determining the age of an ink: indirect dating and direct dating. Indirect dating is based on the chemical analysis of an ink followed by comparison with known samples in a reference collection. The collection should contain information about the inks including the market introduction dates. This approach may allow for an anachronism to be detected. The second concept is based on measuring ink components that change with age. The analysis of solvents in ballpoint inks may be a useful parameter for determining the age of ink on paper. In a previous study, the authors demonstrated that thermal desorption of ink directly from paper, followed by chemical analysis using gas chromatography-mass spectrometry (GC-MS), is a promising procedure for characterizing ink-binder resins and solvents. Preliminary tests showed that monitoring the evaporation of ink solvent from ink on paper is not a suitable method for ink dating. Thermal analysis of ink on paper in two steps revealed that fresh ink releases a relative amount of solvent at a certain low temperature in a defined period of time, which decreases as the ink ages. As a consequence, this relative amount of solvent released at a certain low temperature, and its decrease with time, can be used to estimate ink age. This age-dependent parameter was studied in 85 different inks ranging in age from 1 week to 1.5 years. It was found that some inks showed a significant decrease of this parameter up to an age of several months, and that the aging process can be monitored within this period. For other inks, however, the age-dependent parameter decreases relatively fast, e.g., within a few days, to a constant level, which can be too fast for casework. Based on these results, a general procedure for assessing the age of ballpoint pen inks on paper was developed.  相似文献   
149.
Age determination is a major field of interest in physical and forensic anthropology. Among the different methods based on macroscopic skeletal study, the Iscan method, which analyzes the sternal end of the right fourth rib, is one of the most reliable. We applied the Iscan method to two- and three-dimensional multislice computed tomography (MSCT) reconstructions of the sternal end of the right fourth rib on 39 ribs. The intra-observer variability on MSCT reconstructions was good (gamma coefficient equal to 0.86; value of the Krippendorff's alpha reliability equal to 0.79); inter-observer variability on MSCT reconstructions was also good (gamma coefficient ranging from 0.82 to 0.88; value of the Krippendorff's alpha reliability ranging from 0.78 to 0.86). We demonstrated excellent agreement between the results of analysis of bone samples and those of the two- and three-dimensional images, in particular regarding bone projections, morphology of the pit and of its rim. The accuracy of age estimation did not significantly differ between the Iscan method applied to dry bones and the same method applied to MSCT images. Determination of the Krippendorff's alpha reliability coefficient for the inter-error method confirmed the agreement between phase estimations obtained with the two methods (ranging from 0.55 to 0.71). The real civil age was comprised in 21 cases out of 36 for assessment performed on dry bones and in 23 cases out of 36 on MSCT reconstructions, which represented 58.3% and 63.9%, respectively. Use of MSCT reconstructions in forensic anthropology offers many advantages: no bone preparation, no damage to bone material, and the possibility of application to living individuals.  相似文献   
150.
Detection of ketamine exposure in skeletal tissues by automated enzyme-linked immunosorbent assay (ELISA) and gas chromatography with electron capture detection (GC-ECD) is described. Rats (n = 18) received 0, 15, 30, or 75 mg/kg ketamine hydrochloride acutely (i.p.), and were euthanized within 15 min or 1 h. Ketamine was extracted from ground femoral bone by methanolic incubation followed by liquid-liquid extraction (LLE), while marrow was homogenized in alkaline solution, and then underwent LLE. Extracts were analyzed by ELISA, and subsequently by GC-ECD following derivatization with trifluoroacetic acid anhydride. The effect of tissue type (i.e., diaphyseal bone vs. epiphyseal bone vs. bone marrow) on the immunoassay response was examined through determination of binary classification test sensitivity (S) and measurement of the relative decrease in absorbance (%DA, drug-positive tissues vs. drug-free controls) in each tissue type. The %DA varied significantly between different tissues examined under a given dose condition, and generally decreased in the order marrow > epiphyseal bone > diaphyseal bone, at all dose levels examined. Measured S values for marrow, epiphyseal bone, and diaphyseal bone were 100%, 77%, and 23%, respectively (75 mg/kg dose). These results suggest that the type of skeletal tissue sampled and position sampled within a given bone (diaphyses vs. epiphyses) are important parameters in drug screening of skeletal tissues.  相似文献   
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