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141.
142.
Previous studies have shown that despite having a clear seasonal fluctuation in fecal testosterone concentration, the significantly lower testosterone levels found in velvet stags of the nonseasonal breeder muntjac (Muntiacus sp.) apparently did not stop their spermatogenesis as in other deer species. In the present study, in vitro cultivated Leydig cells isolated from adult stags of three native deer species of Taiwan were treated with androstenedione, with or without adding human chorionic gonadotropin. Results showed that, unlike the two seasonal breeders, sika deer (Cervus nippon) and sambar deer (Rusa unicolor), Leydig cells of velvet muntjac had no dramatic reduction in or even maintained the full capability of their testosterone productivity compared with the hard-antlered stage. The decrease in fecal testosterone level observed earlier in muntjac during the velvet period was probably due to a reduction of number of Leydig cells. These results support the hypothesis that testosterone production in muntjac during its velvet period might never be low enough to trigger the quiescent phase of the reproduction cycle. 相似文献
143.
Pierre BoeschFrédérique Weber-Lotfi Noha IbrahimVladislav Tarasenko Anne CossetFrançois Paulus Robert N. LightowlersAndré Dietrich 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2011,1813(1):186-200
Both endogenous processes and exogenous physical and chemical sources generate deoxyribonucleic acid (DNA) damage in the nucleus and organelles of living cells. To prevent deleterious effects, damage is balanced by repair pathways. DNA repair was first documented for the nuclear compartment but evidence was subsequently extended to the organelles. Mitochondria and chloroplasts possess their own repair processes. These share a number of factors with the nucleus but also rely on original mechanisms. Base excision repair remains the best characterized. Repair is organized with the other DNA metabolism pathways in the organelle membrane-associated nucleoids. DNA repair in mitochondria is a regulated, stress-responsive process. Organelle genomes do not encode DNA repair enzymes and translocation of nuclear-encoded repair proteins from the cytosol seems to be a major control mechanism. Finally, changes in the fidelity and efficiency of mitochondrial DNA repair are likely to be involved in DNA damage accumulation, disease and aging. The present review successively addresses these different issues. 相似文献
144.
145.
目的:分析马来酸氟伏沙明片联合氨磺必利治疗精神分裂症患者的临床疗效及安全性。方法:选择我院2014年2月~2018年2月收治的182例精神分裂症患者,按随机数字表法分为对照组99例和研究组83例。对照组采用氨磺必利治疗,研究组在对照组基础上联合马来酸氟伏沙明片治疗。比较两组临床疗效,治疗前后血脂代谢、总胆汁酸(TBA)水平,阳性与阴性症状量表(PANSS)评分,生活质量,及不良发生情况。结果:治疗后,研究组总有效率为91.57%,显著高于对照组(P<0.05);两组治疗前后空腹血糖(FPG)、糖化血红蛋白(HbA1c)、甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白-C(LDL-C)、高密度脂蛋白-C(HLD-C)、总胆汁酸(TBA)水平比较均无统计学意义(P>0.05);两组治疗后PANSS评分均较治疗前显著下降,生活质量评分较治疗前均明显上升,且研究组PANSS评分显著低于对照组,而生活质量评分明显高于对照组,差异均有统计学意义(P<0.05)。治疗过程中,两组均有体重增加、口渴及便秘发生,两组不良反应发生情况比较差异无统计学意义(P>0.05)。结论:马来酸氟伏沙明片联合氨磺必利治疗能够提高精神分裂症患者疗效,对机体糖脂代谢及肝功能影响较小,有良好的用药安全性。 相似文献
146.
超声成像无创、无放射性、低成本、实时成像的优点,使其成为目前世界上应用最广的成像手段之一。特别是超声造影剂引入之后,超声成像的图像分辨率和灵敏度得到了大大提高,使超声成像在临床上得到了进一步应用。近年来,随着分子生物学和超声成像技术的不断发展,人们提出了"超声分子成像"的概念。它是一项结合了分子靶向造影剂和超声影像技术的能在分子水平下观察病理变化的新兴技术,目前这一技术还处于研究初期阶段。但大量临床前的研究成果已表明超声分子成像在诊断血管生成、炎症和血栓三种疾病具有很大应用前景。本文主要综述了目前常用超声造影剂的种类以及超声分子成像技术的研究现状,并对该技术进行了讨论和展望。 相似文献
147.
Patrick Paulus Katrin Rupprecht Patrick Baer Nicholas Obermüller Daniela Penzkofer Christin Reissig Bertram Scheller Johannes Holfeld Kai Zacharowski Stefanie Dimmeler Joelle Schlammes Anja Urbschat 《PloS one》2014,9(4)
Acute kidney injury (AKI) is one of the most important complications in hospitalized patients and its pathomechanisms are not completely elucidated. We hypothesize that signaling via toll-like receptor (TLR)-3, a receptor that is activated upon binding of double-stranded nucleotides, might play a crucial role in the pathogenesis of AKI following ischemia and reperfusion (IR). Male adult C57Bl6 wild-type (wt) mice and TLR-3 knock-out (-/-) mice were subjected to 30 minutes bilateral selective clamping of the renal artery followed by reperfusion for 30 min 2.5h and 23.5 hours or subjected to sham procedures. TLR-3 down-stream signaling was activated already within 3 h of ischemia and reperfusion in post-ischemic kidneys of wt mice lead to impaired blood perfusion followed by a strong pro-inflammatory response with significant neutrophil invasion. In contrast, this effect was absent in TLR-3-/- mice. Moreover, the quick TLR-3 activation resulted in kidney damage that was histomorphologically associated with significantly increased apoptosis and necrosis rates in renal tubules of wt mice. This finding was confirmed by increased kidney injury marker NGAL in wt mice and a better preserved renal perfusion after IR in TLR-3-/- mice than wt mice. Overall, the absence of TLR-3 is associated with lower cumulative kidney damage and maintained renal blood perfusion within the first 24 hours of reperfusion. Thus, we conclude that TLR-3 seems to participate in the pathogenesis of early acute kidney injury. 相似文献
148.
Colm G. Connolly Amanda Bischoff-Grethe Stephan J. Jordan Steven Paul Woods Ronald J. Ellis Martin P. Paulus Igor Grant for The Translational Methamphetamine AIDS Research Center Group 《PloS one》2014,9(10)
Background
Risky decision-making is commonly observed in persons at risk for and infected with HIV and is associated with executive dysfunction. Yet it is currently unknown whether HIV alters brain processing of risk-taking decision-making.Methods
This study examined the neural substrate of a risky decision-making task in 21 HIV seropositive (HIV+) and 19 seronegative (HIV-) comparison participants. Functional magnetic resonance imaging was conducted while participants performed the risky-gains task, which involves choosing among safe (20 cents) and risky (40/80 cent win or loss) choices. Linear mixed effects analyses examining group and decision type were conducted. Robust regressions were performed to examine the relationship between nadir CD4 count and Kalichman sexual compulsivity and brain activation in the HIV+ group. The overlap between the task effects and robust regressions was explored.Results
Although there were no serostatus effects in behavioral performance on the risky-gains task, HIV+ individuals exhibited greater activation for risky choices in the basal ganglia, i.e. the caudate nucleus, but also in the anterior cingulate, dorsolateral prefrontal cortex, and insula relative to the HIV- group. The HIV+ group also demonstrated reduced functional responses to safe choices in the anterior cingulate and dorsolateral prefrontal cortex relative to the HIV- group. HIV+ individuals with higher nadir CD4 count and greater sexual compulsivity displayed lower differential responses to safe versus risky choices in many of these regions.Conclusions
This study demonstrated fronto-striatal loop dysfunction associated with HIV infection during risky decision-making. Combined with similar between-group task behavior, this suggests an adaptive functional response in regions critical to reward and behavioral control in the HIV+ group. HIV-infected individuals with higher CD4 nadirs demonstrated activation patterns more similar to seronegative individuals. This suggests that the severity of past immunosuppression (CD4 nadir) may exert a legacy effect on processing of risky choices in the HIV-infected brain. 相似文献149.
Jeanne Rini Poespoprodjo Wendy Fobia Enny Kenangalem Daniel A. Lampah Paulus Sugiarto Emiliana Tjitra Nicholas M. Anstey Ric N. Price 《PloS one》2014,9(1)
Background
Artemisinin combination therapy (ACT) is recommended for the treatment of multidrug resistant malaria in the second and third trimesters of pregnancy, but the experience with ACTs is limited. We review the exposure of pregnant women to the combination dihydroartemisinin-piperaquine over a 6 year period.Methods
From April 2004–June 2009, a prospective hospital-based surveillance screened all pregnant women for malaria and documented maternal and neonatal outcomes.Results
Data were available on 6519 pregnant women admitted to hospital; 332 (5.1%) women presented in the first trimester, 324 (5.0%) in the second, 5843 (89.6%) in the third, and in 20 women the trimester was undocumented. Peripheral parasitaemia was confirmed in 1682 women, of whom 106 (6.3%) had severe malaria. Of the 1217 women admitted with malaria in the second and third trimesters without an impending adverse outcome, those treated with DHP were more likely to be discharged with an ongoing pregnancy compared to those treated with a non-ACT regimen (Odds Ratio OR = 2.48 [1.26–4.86]); p = 0.006. However in the first trimester 63% (5/8) of women treated with oral DHP miscarried compared to 2.6% (1/38) of those receiving oral quinine; p<0.001. Of the 847 women admitted for delivery those reporting a history of malaria during their pregnancy who had been treated with quinine-based regimens rather than DHP had a higher risk of malaria at delivery (adjusted OR = 1.56 (95%CI 0.97–2.5), p = 0.068) and perinatal mortality (adjusted OR = 3.17 [95%CI: 1.17–8.60]; p = 0.023).Conclusions
In the second and third trimesters of pregnancy, a three day course of DHP simplified antimalarial treatment and had significant benefits over quinine-based regimens in reducing recurrent malaria and poor fetal outcome. These data provide reassuring evidence for the rational design of prospective randomized clinical trials and pharmacokinetic studies. 相似文献150.
Ingrid M. Bonilla Victor P. Long III Pedro Vargas-Pinto Patrick Wright Andriy Belevych Qing Lou Kent Mowrey Jae Yoo Philip F. Binkley Vadim V. Fedorov Sandor Gy?rke Paulus M. L. Janssen Ahmet Kilic Peter J. Mohler Cynthia A. Carnes 《PloS one》2014,9(10)
The role of IKCa in cardiac repolarization remains controversial and varies across species. The relevance of the current as a therapeutic target is therefore undefined. We examined the cellular electrophysiologic effects of IKCa blockade in controls, chronic heart failure (HF) and HF with sustained atrial fibrillation. We used perforated patch action potential recordings to maintain intrinsic calcium cycling. The IKCa blocker (apamin 100 nM) was used to examine the role of the current in atrial and ventricular myocytes. A canine tachypacing induced model of HF (1 and 4 months, n = 5 per group) was used, and compared to a group of 4 month HF with 6 weeks of superimposed atrial fibrillation (n = 7). A group of age-matched canine controls were used (n = 8). Human atrial and ventricular myocytes were isolated from explanted end-stage failing hearts which were obtained from transplant recipients, and studied in parallel. Atrial myocyte action potentials were unchanged by IKCa blockade in all of the groups studied. IKCa blockade did not affect ventricular myocyte repolarization in controls. HF caused prolongation of ventricular myocyte action potential repolarization. IKCa blockade caused further prolongation of ventricular repolarization in HF and also caused repolarization instability and early afterdepolarizations. SK2 and SK3 expression in the atria and SK3 in the ventricle were increased in canine heart failure. We conclude that during HF, IKCa blockade in ventricular myocytes results in cellular arrhythmias. Furthermore, our data suggest an important role for IKCa in the maintenance of ventricular repolarization stability during chronic heart failure. Our findings suggest that novel antiarrhythmic therapies should have safety and efficacy evaluated in both atria and ventricles. 相似文献