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21.
为了分离培养牦牛子宫内膜细胞,并探讨不同浓度雌激素和孕激素对上皮细胞和基质细胞增殖的影响,采用Ⅰ型胶原酶消化、离心分离和差速消化纯化的方法分离纯化上皮细胞和基质细胞,对其进行免疫细胞化学染色鉴定,绘制生长曲线,最后用MTT法测定不同浓度的17β-雌二醇和孕酮对细胞增殖的影响。结果显示,1g/L胶原酶消化1h,500r/min离心10min,经2代差速消化纯化获得的上皮细胞的纯度为96%,基质细胞的纯度为93%;不同浓度的17β-雌二醇均能促进上皮细胞和基质细胞的增殖,孕酮可促进基质细胞的增殖,但对上皮细胞的增殖有抑制作用,不同浓度的17β-雌二醇和孕酮共同作用均能显著促进基质细胞增殖,而对上皮细胞增殖的影响随混合液中孕酮浓度的增加由促进转为抑制。本研究获得了高纯度的牦牛子宫内膜上皮细胞和基质细胞,证实雌激素能促进2种细胞的增殖,孕激素能促进基质细胞的增殖但抑制上皮细胞的增殖。  相似文献   
22.
The carotid bodies tend to enlarge after long-standing cardiopulmonary disease. Our objective was to investigate whether cardiac hypertrophy is associated with carotid body hyperplasia. Fifteen autopsy cases with combined left and right ventricular hypertrophy were examined and compared with two control groups (16 cases). The study involved a meticulous dissection of carotid bifurcations, thin serial sections, and morphometric analysis of carotid body volume and cell types (progenitor, dark, light, and sustentacular). There was a significant increase in sustentacular cells in all individuals with cardiac hypertrophy, which was not drug-induced, and accompanied by a similar increase in carotid body volume. Dark or light cell accumulation was detected focally and only in three instances. It appears that the generalized sustentacular cell hyperplasia is the result of long-standing hypoxia, while a superimposed focal prominence of dark or light cells may be proliferative or metaplastic in nature and attributed to short-term hypoxia.  相似文献   
23.
通过了解MDCK细胞感染犬细小病毒(CPV)后基因表达水平的差异,研究病毒对细胞的致病作用以及细胞抵御病毒感染的机制。利用表达谱基因芯片技术,分析持续感染犬细小病毒的MDCK细胞基因表达水平的变化情况,并用Real-Time PCR技术加以验证。结果显示,获得了359个差异大于1.5倍的表达基因(P0.05),占总基因数的1.53%,其中193个上调表达(0.84%),166个下调表达(0.69%)。对差异基因进行GO功能聚类分析,小部分涉及免疫应答、生长周期调控、信号转导和蛋白酶活性,其他大部分基因功能未知。利用Real-Time PCR随机验证5个基因在持续感染CPV后的差异表达,其结果和芯片杂交的结果一致。表明建立了MDCK细胞持续感染CPV后的差异表达谱,初步了解到CPV对宿主细胞的制约作用,引起部分细胞增殖调控相关基因发生了表达下调,以及细胞对感染的积极应答反应,部分免疫反应基因、肽链内切酶活性基因等发生了上调表达,从而为探索病毒的致病机理和宿主的抗病毒途径提供了试验基础。  相似文献   
24.
An acceptable area for collecting DNA reference sample is a part of the forensic DNA analysis development. The aim of this study was to evaluate skin surface cells (SSC) as an alternate source of reference DNA sample. From each volunteer (n = 10), six samples from skin surface areas (forearm and fingertips) and two traditional samples (blood and buccal cells) were collected. Genomic DNA was extracted and quantified then genotyped using standard techniques. The highest DNA concentration of SSC samples was collected using the tape/forearm method of collection (2.1 ng/μL). Cotton swabs moistened with ethanol yielded higher quantities of DNA than swabs moistened with salicylic acid, and it gave the highest percentage of full STR profiles (97%). This study supports the use of SSC as a noninvasive sampling technique and as a extremely useful source of DNA reference samples among certain cultures where the use of buccal swabs can be considered socially unacceptable.  相似文献   
25.
人体死后肝细胞DNA含量与死亡时间关系的研究   总被引:1,自引:0,他引:1  
目的研究人体死后肝脏细胞DNA含量变化与死亡时间的关系及影响因素。方法选取46例已知死亡时间的人体肝脏,根据离体肝脏所处的环境温度分为12—19%(A组)和20—27%(B组)两组,每组23例。在死后24~72h内每隔4h穿刺取肝组织1次,制成细胞悬液,经RNA酶消化,PI染色后,用流式细胞仪测定被检测细胞中含不完整DNA的细胞数所占百分比,所得数据经Exp032V1.2软件计算N值。结果死后24~72h肝细胞N平均值,A组从10.91%增至49.72%,B组从16.22%增至69.63%。两组N平均值随死亡时间的延长均逐渐增高,与死亡时间有相关性,A组r值为:0.598,B组r值为0.77357。并且建立了不同环境温度对应的回归方程。结论在不同环境温度下,死后24~72h内人体肝脏细胞DNA降解均随死亡时间的延长和环境温度的升高而逐渐加快,相关数据可望为死亡时间推断提供一定参考依据。  相似文献   
26.
Since the introduction in 2001 of a urine-based detection method for recombinant erythropoietin (rHuEPO), transfusion-doping practices have regained interest. To address this problem, an efficient antidoping test designed to obtain direct proof of allogeneic blood transfusion was developed and validated. This test, based on flow cytometry analysis of red blood cell (RBCs) phenotypes, was used to determine the absence or the presence of numerous RBCs populations in a blood sample. A such, it may constitute a direct proof of an abnormal blood population resulting from homologous transfusion. Single-blind and single-site studies were carried out to validate this method as a forensic quality standard analysis and to allow objective interpretation of real cases. The analysis of 140 blood samples containing different percentages (0-5%) of a minor RBCs population were carried on by four independent analysts. Robustness, sensitivity, specificity, precision and stability were assessed. ISO-accredited controls samples were used to demonstrate that the method was robust, stable and precise. No false positive results were observed, resulting in a 100% specificity of the method. Most samples containing a 1.5% minor RBCs population were unambiguously detected, yielding a 78.1% sensitivity. These samples mimicked blood collected from an athlete 3 months after a homologous blood transfusion event where 10% of the total RBCs present in the recipient originated in the donor. The observed false negative results could be explained by differences in antigen expression between the donor and the recipient. False negatives were more numerous with smaller minor RBCs populations. The method described here fulfils the ISO-17025 accreditation and validation requirements. The controls and the methodology are solid enough to determine with certainty whether a sample contains one or more RBCs populations. This variable is currently the best indicator for homologous blood transfusion doping.  相似文献   
27.
冬虫夏草菌丝水提液对SP2/0细胞凋亡的影响   总被引:3,自引:0,他引:3  
在冬虫夏草菌丝水提液诱导下,采用Hoechst33342荧光染色、MTT、琼脂糖凝胶电泳和流式细胞仪等方法,观察和分析了SP2/0细胞的凋亡情况。结果显示,冬虫夏草菌丝水提液可抑制SP2/0细胞增殖,在荧光显微镜下,凋亡细胞呈亮绿色,DNA琼脂糖电泳可见典型的“阶梯状”条带,Annexin-V-FITC和碘化丙啶(PI)双染后流式细胞仪分析显示,细胞凋亡数量明显增多。表明,冬虫夏草菌丝水提液对SP2/0细胞增殖的抑制作用可能与诱导其凋亡有关。  相似文献   
28.
Multiple DNA transfer has increasingly been brought up in court as potential means for the presence of the defendants DNA at the crime scene or on a piece of evidence. This has prompted several investigations into DNA transfer under very controlled and semi-controlled conditions, however little is published about DNA transfer in “uncontrolled” or real life situations.Here we examined the effects of multiple direct and indirect transfer of DNA within a small group of people and objects: three individuals participating in a social interaction of having a drink (jug of juice) together for 20 min. At the end of the tests all the surfaces of interest were sampled and analyzed.In many instances the last person or the only person to come in contact with the object was the main or the only depositor of the DNA detected on it. The jug was a clear vector for secondary DNA transfer. Interestingly, in many instances the participants acted as vectors for foreign DNA transfer.  相似文献   
29.
目的建立脱落细胞负压吸附方法,用于DNA检验中衣物等载体上人体脱落细胞的采集。方法检材包括由志愿者佩带1、5、10、20m in纱线手套,穿着5、10、20m in的内衣以及外套、鞋、帽子、头套、袜子、水杯、矿泉水瓶等。在吸尘器的进风口处连接特制的吸筒,一端覆盖具有拦截和静电吸附细胞能力的特制吸附膜,选择适当负压对各检材相应部位进行吸扫。收集吸附膜上的脱落细胞,采用Chelex-100法提取DNA,AmpFLSTR Identifiler复合扩增试剂盒扩增检测。结果上述检材用本文负压吸附法采集人体脱落细胞,经检验均获得清晰、完整的STR分型图谱,并与检材提供者的基因型一致。结论本文建立的脱落细胞负压吸附技术可有效吸附载体上的脱落细胞,适用于DNA检案实践。  相似文献   
30.
In this study, analyzing nationally represented survey data collected in 2003, we consider the roots of issue-specific citizen participation in the controversy over embryonic stem cell research and therapeutic cloning. Building on past research, we pay particular theoretical attention to the role of issue engagements, the impact of church-based recruitment, and the influence of news media attentiveness. Given the increasing emphasis in science policy circles on creating new forms of public engagement, we also measure citizen willingness to attend and participate in a proposed local deliberative forum on the stem cell debate. Results indicate that traditional forms of citizen activism in the controversy over embryonic stem cell research and cloning is rooted almost exclusively in direct requests for participation through religious organizations rather than socio-economic differences among respondents, though issue engagement (measured as opinion intensity) and news attentiveness also play an important role. In terms of deliberative forums, traditional resource factors are significant, as the citizens who indicate they are most likely to participate in such a hypothetical local town meeting are generally highly educated, white, and younger. Above and beyond these resource factors, however, citizens willing to participate are also likely to have received requests to get involved in the debate at church, hold more intense feelings about the issue, and are paying closer attention to news coverage. In the future, in order to ensure the normative goals of diverse and/or representative participation, if actual deliberative forums are employed, these findings suggest that organizers will need to focus heavily on purposive sampling and turn out efforts.
Kirby GoidelEmail:
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