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1.
Neutrophils readily infiltrate infection foci, phagocytose and usually destroy microbes. In tuberculosis (TB), a chronic pulmonary infection caused by Mycobacterium tuberculosis (Mtb), neutrophils harbor bacilli, are abundant in tissue lesions, and their abundances in blood correlate with poor disease outcomes in patients. The biology of these innate immune cells in TB is complex. Neutrophils have been assigned host-beneficial as well as deleterious roles. The short lifespan of neutrophils purified from blood poses challenges to cell biology studies, leaving intracellular biological processes and the precise consequences of Mtb–neutrophil interactions ill-defined. The phenotypic heterogeneity of neutrophils, and their propensity to engage in cellular cross-talk and to exert various functions during homeostasis and disease, have recently been reported, and such observations are newly emerging in TB. Here, we review the interactions of neutrophils with Mtb, including subcellular events and cell fate upon infection, and summarize the cross-talks between neutrophils and lung-residing and -recruited cells. We highlight the roles of neutrophils in TB pathophysiology, discussing recent findings from distinct models of pulmonary TB, and emphasize technical advances that could facilitate the discovery of novel neutrophil-related disease mechanisms and enrich our knowledge of TB pathogenesis.  相似文献   
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孟祥娟  田军 《计算机时代》2012,(1):44-45,48
介绍了病理学精品课程网站的建设以及在线考试系统的实现技术,从提高网站建设和在线测试质量的角度研究探讨了在线测试系统。该系统对病理学课程教学质量和水平的提高能起到积极的促进作用,并可在其他课程的标准化考试中推广应用。  相似文献   
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Regular physical activity in cyclic sports can influence the so-called “angiogenic switch”, which is considered as an imbalance between proangiogenic and anti-angiogenic molecules. Disruption of the synthesis of angiogenic molecules can be caused by local changes in tissues under the influence of excessive physical exertion and its consequences, such as chronic oxidative stress and associated hypoxia, metabolic acidosis, sports injuries, etc. A review of publications on signaling pathways that activate and inhibit angiogenesis in skeletal muscles, myocardium, lung, and nervous tissue under the influence of intense physical activity in cyclic sports. Materials: We searched PubMed, SCOPUS, Web of Science, Google Scholar, Clinical keys, and e-LIBRARY databases for full-text articles published from 2000 to 2020, using keywords and their combinations. Results: An important aspect of adaptation to training loads in cyclic sports is an increase in the number of capillaries in muscle fibers, which improves the metabolism of skeletal muscles and myocardium, as well as nervous and lung tissue. Recent studies have shown that myocardial endothelial cells not only respond to hemodynamic forces and paracrine signals from neighboring cells, but also take an active part in heart remodeling processes, stimulating the growth and contractility of cardiomyocytes or the production of extracellular matrix proteins in myofibroblasts. As myocardial vascularization plays a central role in the transition from adaptive heart hypertrophy to heart failure, further study of the signaling mechanisms involved in the regulation of angiogenesis in the myocardium is important in sports practice. The study of the “angiogenic switch” problem in the cerebrovascular and cardiovascular systems allows us to claim that the formation of new vessels is mediated by a complex interaction of all growth factors. Although the lungs are one of the limiting systems of the body in cyclic sports, their response to high-intensity loads and other environmental stresses is often overlooked. Airway epithelial cells are the predominant source of several growth factors throughout lung organogenesis and appear to be critical for normal alveolarization, rapid alveolar proliferation, and normal vascular development. There are many controversial questions about the role of growth factors in the physiology and pathology of the lungs. The presented review has demonstrated that when doing sports, it is necessary to give a careful consideration to the possible positive and negative effects of growth factors on muscles, myocardium, lung tissue, and brain. Primarily, the “angiogenic switch” is important in aerobic sports (long distance running). Conclusions: Angiogenesis is a physiological process of the formation of new blood capillaries, which play an important role in the functioning of skeletal muscles, myocardium, lung, and nervous tissue in athletes. Violation of the “angiogenic switch” as a balance between proangiogenic and anti-angiogenic molecules can lead to a decrease in the functional resources of the nervous, musculoskeletal, cardiovascular, and respiratory systems in athletes and, as a consequence, to a decrease in sports performance.  相似文献   
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采用2011年1月-2014年6月在云南省第一人民医院确诊并行手术治疗的58例胰腺癌患者,切除部分肿瘤组织作为实验标本,癌旁组织作为对照,利用免疫组化及Western blot检测晚期胰腺癌组织内神经生长因子(nerve growth factor,NGF)及神经生长因子前体(precursor of nerve growth factor,pro NGF)的表达,Gel-Pro analyzer 4图像分析系统分析Western条带密度.试验重复3次,取3次IOD值行统计学分析.免疫组化及Western blot结果显示肿瘤组织NGF的表达较癌旁组织明显增高,而pro NGF的表达较癌旁组织明显降低.半定量Western blot显示癌旁组织和肿瘤组织NGF表达的IOD值分别为113.33±8.54和285.00±15.13,pro NGF表达的IOD值分别为245.00±7.55和86.33±7.37,差异有统计学意义(P0.05).因此,晚期胰腺癌患者肿瘤组织内NGF/pro NGF的比例发生改变,组织内NGF蓄积,而pro NGF减少,这可能是导致胰腺癌肿瘤细胞凋亡减少,生长、浸润和迁徙功能增强的重要机制之一.  相似文献   
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现代技术既给人类带来了进步与繁荣,又给文明世界带来许多令人担忧的问题。对于处在特型时期的中国来说,一方面,为了能迅速地赶上西方发达国家的现代化程度,必须大力弘扬以技术理性和人之主体性为内涵的现代性核心理念,必须大力发展现代技术;另一方面,市场经济和工业文明又会不可避免地把一个异化的世界摆在我们面前,技术问题不仅表现在导致生态环境的破坏,而且也使文明陷入困境。因此,在当下对技术问题进行研究具有重要意义。作者借用社会病理学的学术资源对技术问题的概念进行了界定,并对技术问题的自然维度进行了考察。  相似文献   
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Reports an error in "Prospective Relations Between Bulimic Pathology, Depression, and Substance Abuse: Unpacking Comorbidity in Adolescent Girls" by Eric Stice, Emily M. Burton and Heather Shaw (Journal of Consulting and Clinical Psychology, 2004[Feb], Vol 72[1], 62-71). The findings of Leon, Fulkerson, Perry, Keel, and Klump ("Three to four year prospective evaluation of personality and behavioral risk factors for later disordered eating in adolescent girls and boys," Journal of Youth and Adolescence, 1999, Vol. 28, No. 2, pp. 181-196), cited on page 62, were incorrectly reported. Leon et al. (1999) found that the latent variable of negative affect/attitudes determined at study entrance significantly correlated with final year eating disorder risk score when conducted with the full sample and when removing Time 1 high eating disorder risk subjects. This latent variable consisted of the GBI Depression, MPQ Negative Emotionality, EDI Ineffectiveness, EDI Interoceptive Awareness, and EDI Body Dissatisfaction scales. A subsequent univariate analysis of Time 1 Negative Emotionality scale score on Time 3 eating disorder risk, adjusting for initial eating disorder risk score, showed a nonsignificant effect size (Stice, E. [2002]. Risk and maintenance factors for eating pathology: A meta-analytic review. Psychological Bulletin, 128, 825-848). (The following abstract of the original article appeared in record 2004-10364-006.) To elucidate the processes that contribute to the comorbidity between bulimic pathology, depression, and substance abuse, the authors tested the temporal relations between these disturbances with prospective data from adolescent girls (N = 496). Multivariate analyses indicated that depressive symptoms predicted onset of bulimic pathology but not of substance abuse, bulimic symptoms predicted onset of depression but not of substance abuse, and substance abuse symptoms predicted onset of depression but not of bulimic pathology. Results suggest that the comorbidity arises because certain disorders are risk factors for the other disorders. Findings also provide support for select etiologic theories and further establish the clinical significance of these conditions by showing that they increase risk for onset of other psychiatric disturbances. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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《Planning》2016,(4)
目的 分析初诊无远处转移的穿刺病理Gleason评分为10分前列腺癌的临床特点并探讨外放疗联合内分泌治疗的疗效。方法 2003年1月至2014年3月北京协和医院收治初诊无远处转移的Gleason评分10分前列腺癌患者9例。所有患者均接受全盆腔外放疗联合长期内分泌治疗。全盆腔外放疗的照射剂量为50.0 Gy,前列腺、双侧精囊腺及区域阳性淋巴结加量至76.2~78.0 Gy。内分泌治疗采用最大限度雄激素阻断:口服抗雄激素药物加每月注射一次黄体生成素释放激素类似物。分析患者临床特点及联合治疗效果,并运用Kaplan-Meier法绘制生存曲线。 结果 患者中位随访时间为4.8年(26~75个月)。治疗前中位血清前列腺特异性抗原(prostate specific antigen,PSA)为11.2 μg/L,其中6例低于20 μg/L,3例高于70 μg/L。中位穿刺活检针数阳性率为90.9%。TNM分期:3例T2c,4例T3a,2例T3b;6例N0,3例N1;9例M0。随访期间,6例患者出现生化复发,其中5例进一步发展为转移性前列腺癌;4例患者死亡,其中3例死于前列腺癌。5年无生化复发率、无远处转移率、肿瘤特异性生存率及总体生存率分别为28.6%、 57.1%、66.7% 和57.1%。5例出现1~2级早期放疗胃肠道不良反应,6例出现1~2级早期泌尿系统不良反应,无晚期胃肠道及泌尿系统不良反应。无骨折、心血管意外等严重内分泌治疗并发症。 结论 初诊无远处转移的穿刺病理Gleason评分10分前列腺癌常伴穿刺阳性范围大、肿瘤分期偏晚等高危因素,患者通常预后不良,放疗联合内分泌治疗等及时和积极的综合治疗方案往往是必需的。  相似文献   
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The American Psychological Association 2010 Award for Distinguished Scientific Early Career Contributions to Psychology was awarded to Stanley F. Floresco, for his outstanding and innovative research on neural mechanisms linking brain activity to critical cognitive functions including risk-based decision making, cognitive flexibility, working memory, and other aspects of executive function. His novel findings form an empirical base for understanding how neural pathology may underlie aspects of psychotic behavior and as such validate neuropsychopharmacological approaches to mental ill health. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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