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71.
72.
目的:观察细胞色素P450系统药物代谢酶CYP2C19基因多态性以及相关临床因素对氯吡格雷抵抗的影响。方法:选择2010年11月至2011年5月我科拟行PCI术治疗的冠心病患者共145例,均给予氯吡格雷300mg负荷剂量,75mg维持剂量。①通过流式细胞仪检测血管舒张因子刺激酸磷蛋白血小板反应性指数VASP PRI(以VASP PRI≥50%,定义为氯吡格雷抵抗)分为氯吡格雷抵抗组和氯吡格雷反应组。②检测入选患者的药物代谢酶CYP2C19的基因型;根据不同等位基因功能缺失,分为快代谢基因型(*1/*1)、中间代谢基因型(*1/*2、*1/*3)和慢代谢基因型(*2/*2、*2/*3、*3/*3)。③观察CYP2C19基因型及相关临床危险因素对氯吡格雷反应性的影响,④观察氯吡格雷抵抗与临床不良终点事件主要临床不良终点事件[心源性死亡、再发心肌梗死、靶病变再次血运重建术(TLR)]和次要临床终点事件(支架内血栓形成、脑血管意外、大出血)之间的相关性。结果:检测出氯吡格雷抵抗的患者31例,其发生率为20.67%;检测出CYP2C19慢代谢基因型携带患者19例,所占比例为12.67%。慢代谢基因型患者与(快代谢基因型+中间代谢基因型患者)之间VASP PRI比为(49.20±8.45)%VS(44.17±5.41)%,P<0.05,氯吡格雷抵抗发生率之比为35.49%(n=11)VS16.81%(n=20),P<0.05。多元回归分析提示CYP2C19慢代谢基因型(OR:4.43;95%CI:3.28-8.37,P<0.05)和2型糖尿病(OR:2.76;95%CI:2.13-6.14;P<0.05)是氯吡格雷抵抗的两种危险因素。临床随访结果显示氯吡格雷抵抗组与氯吡格雷反应组主要临床不良终点事件的发生率比为6.45%(n=2)vs2.63%(n=3),P<0.05。结论:携带CPY2C19慢代谢基因型和患有2型糖尿病是导致氯吡格雷抵抗的两种重要的危险因素,氯吡格雷抵抗的发生增加了临床不良终点事件的风险。 相似文献
73.
74.
A novel neurotoxoid vaccine prevents mucosal botulism 总被引:4,自引:0,他引:4
Kobayashi R Kohda T Kataoka K Ihara H Kozaki S Pascual DW Staats HF Kiyono H McGhee JR Fujihashi K 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(4):2190-2195
The threat posed by botulism, classically a food- and waterborne disease with a high morbidity and mortality, has increased exponentially in an age of bioterrorism. Because botulinum neurotoxin (BoNT) could be easily disseminated by terrorists using an aerosol or could be used to contaminate the food or water supply, the Centers for Disease Control and Prevention and the National Institute of Allergy and Infectious Diseases has classified it as a category A agent. Although clearly the development of a safe and effective mucosal vaccine against this toxin should be a high priority, essentially no studies to date have assessed mucosal immune responses to this disease. To bridge this gap in our knowledge, we immunized mice weekly for 4 wk with nasal doses of BoNT type A toxoid and a mutant of cholera toxin termed E112K. We found elevated levels of BoNT-specific IgG Abs in plasma and of secretory IgA Abs in external secretions (nasal washes, saliva, and fecal extracts). When mice given nasal BoNT vaccine were challenged with 4 x 10(3) LD50 of BoNT type A (BoNT/A) via the i.p. route, complete protection was seen, while naive mice given the same dosage died within 2 h. To further confirm the efficacy of this nasal BoNT vaccine, an oral LD50 was determined. When mice were given an oral challenge of 5 microg (2 x oral LD50) of progenitor BoNT/A, all immunized mice survived beyond 5 days, while nonimmunized mice did not. The fecal extract samples from nasally vaccinated mice were found to contain neutralizing secretory IgA Abs. Taken together, these results show that nasal BoNT/A vaccine effectively prevents mucosal BoNT intoxication. 相似文献
75.
AIMS: The biopesticide effect of four green composts against fusarium wilt in melon plants and the effect of soil quality in soils amended with composts were assayed. METHODS AND RESULTS: The composts consisted of pruning wastes, with or without addition of coffee wastes (3/1 and 4/1, dry wt/dry wt) or urea (1000/1, dry wt/dry wt). In vitro experiments suggested the biopesticide effect of the composts against Fusarium oxysporum, while only the compost of pine bark and urea (1000/1dry wt/dry wt) had an abiotic effect. Melon plant growth with composts and F. oxysporum was one to four times greater than in the non-amended soil, although there was no significant decrease in the level of the F. oxysporum in the soil. The addition of composts to the soil also improved its biological quality, as assessed by microbiological and biochemical parameters: ATP and hydrolases involved in the P (phosphatase), C (beta-glucosidase) and N (urease) cycles. CONCLUSIONS: Green composts had greater beneficial characteristics, improved plant growth and controlled fusarium wilt in melon plants. These composts improve the soil quality of semi-arid agricultural soils. SIGNIFICANCE AND IMPACT OF THE STUDY: Biotic and abiotic factors from composts have been tested as responsible of their biopesticide activity against fusarium wilt. 相似文献
76.
From the whole plant of Ajuga chamaepitys two new neo-clerodane diterpenoids, ajugapitin and its dihydro derivative, have been isolated. Their 相似文献
77.
目的:利用喷雾干燥工艺制备芽孢杆菌dhs-330-021菌粉,并研究菌粉的活性及稳定性。方法:以脱脂乳、海藻糖、β-环糊精和谷氨酸钠为保护剂,采用喷雾干燥(条件为:进口温度100℃,出口温度50~60℃,进样速度2~4mL/min)制备芽孢杆菌菌粉,以喷干存活率和菌粉活菌数为指标,选择最佳制备条件。结果:获得喷干保护剂配方为脱脂乳10.0%、海藻糖6.0%、β-环糊精13.0%、谷氨酸钠15.0%,喷干存活率为65.9%,菌粉活菌数为1.38×109CFU/g,存放180 d后菌粉活菌数为1.03×10~9CFU/g。结论:喷雾干燥工艺可以用于芽孢杆菌dhs-330-021菌粉的制备,获得的菌粉稳定性较好。 相似文献
78.
司光伟 《生物化学与生物物理进展》2023,50(6):1243-1243
Acetylcholine, the first identified neurotransmitter, plays crucial roles in various brain functions. One well-known case is its involvement as an activating neurotransmitter in the regulation of locomotion. However, its inhibitory regulatory role, particularly in locomotion, remains poorly understood. In a study conducted by Polat et al., the authors investigated the inhibitory role of acetylcholine in locomotion in C. elegans. In this organism, the acetylcholine-gated chloride channel receptor consists of four subunits. The authors thoroughly examined the loss-of-function of each subunit in movement regulation. Interestingly, the mutant worms were still capable of performing various movements such as forward, backward crawling, and turning, suggesting that the overall movement was not significantly affected. However, quantitative behavior analysis revealed subtle yet significant differences in the timing and postures of the movement in these mutants. Furthermore, the authors employed optogenetics to stimulate a specific neuron involved in backward crawling and demonstrated that the loss-of-function of the receptors in individual neurons affects the transitioning between locomotion modes.
This work provides evidence for the inhibitory regulatory role of acetylcholine in locomotion. The loss-of-function of acetylcholine-gated chloride channel receptors likely disrupts the balance of neuronal and circuit physiology, thereby affecting the regulation of locomotion. Moreover, this study highlights the powerful role of quantitative behavior analysis in discovering and understanding more sophisticated functions of neural circuits. 相似文献
79.
物质使用障碍(substance use disorder,SUD)是一个全球性的卫生和社会问题。针对大多数成瘾性物质,目前还没有有效的治疗药物,普遍还是采用心理治疗和行为矫治。近年来,针刺、深部脑刺激(DBS)、重复经颅磁刺激(rTMS)、经颅直流电刺激(tDCS)和运动等非药物干预手段在治疗神经系统疾病的有效性逐渐得到重视。越来越多的研究也开始关注非药物干预手段在治疗SUD中的应用。本综述在文献检索(如PubMed、Google Scholar等)的基础上总结了针刺、DBS、rTMS、tDCS和运动等非药物干预手段对阿片类药物、精神活性物质、尼古丁、酒精等不同成瘾性物质的心理渴求、戒断时间、使用剂量和成瘾伴随的情绪、认知功能障碍等的影响。研究表明,针刺、DBS、rTMS、tDCS和运动等非药物干预手段可以有效降低成瘾性物质引起的心理渴求、降低物质摄入量、增加戒断时间,同时改善长期使用成瘾性物质引起的认知障碍、焦虑和抑郁样行为等。如果非药物干预手段结合药物、心理等治疗方式,效果更佳。尽管非药物干预方法在现阶段主要作为辅助性治疗手段,未来的研究应注重明确非药物干预手段的神经生物学机制,... 相似文献
80.
为了研究褪黑激素(Melatonin,MLT)对休情期银黑狐腔前卵泡卵母细胞超微结构的影响。本研究选取健康7月龄埋植和未埋植MLT的银黑狐各5只,取其左侧卵巢共计10枚,制备超薄切片后利用透射电镜分别观察每枚卵巢的各级腔前卵泡各1-5个,并进行拍照。结果埋植和未埋植MLT的银黑狐原始卵泡卵母细胞内均有少量线粒体和高尔基体,而未埋植MLT的银黑狐卵母细胞中还可见少量滑面内质网;初级卵泡卵母细胞内,均开始形成不完整透明带,线粒体及内质网数量均有所增加,沿透明带出现少量皮质颗粒;次级卵泡阶段,未埋植MLT银黑狐卵母细胞微绒毛数量较埋植MLT的多,其余细胞器未见差异。结果表明,MLT对休情期银黑狐卵巢腔前卵泡卵母细胞的线粒体、脂滴、高尔基体、皮质颗粒等细胞器的发育没有影响,仅对初级卵泡阶段内质网的发育有抑制作用。 相似文献