全文获取类型
收费全文 | 501篇 |
免费 | 19篇 |
国内免费 | 3篇 |
专业分类
儿科学 | 4篇 |
基础医学 | 38篇 |
口腔科学 | 2篇 |
临床医学 | 50篇 |
内科学 | 40篇 |
皮肤病学 | 2篇 |
神经病学 | 62篇 |
特种医学 | 4篇 |
外科学 | 11篇 |
综合类 | 79篇 |
预防医学 | 43篇 |
眼科学 | 1篇 |
药学 | 176篇 |
中国医学 | 8篇 |
肿瘤学 | 3篇 |
出版年
2022年 | 7篇 |
2021年 | 5篇 |
2020年 | 7篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 12篇 |
2016年 | 5篇 |
2015年 | 9篇 |
2014年 | 21篇 |
2013年 | 52篇 |
2012年 | 21篇 |
2011年 | 33篇 |
2010年 | 24篇 |
2009年 | 23篇 |
2008年 | 33篇 |
2007年 | 28篇 |
2006年 | 25篇 |
2005年 | 18篇 |
2004年 | 13篇 |
2003年 | 10篇 |
2002年 | 13篇 |
2001年 | 6篇 |
2000年 | 9篇 |
1998年 | 5篇 |
1997年 | 7篇 |
1995年 | 4篇 |
1993年 | 6篇 |
1992年 | 3篇 |
1991年 | 7篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 10篇 |
1987年 | 5篇 |
1985年 | 6篇 |
1984年 | 8篇 |
1982年 | 3篇 |
1981年 | 2篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1978年 | 6篇 |
1977年 | 4篇 |
1976年 | 7篇 |
1975年 | 4篇 |
1974年 | 3篇 |
1973年 | 5篇 |
1972年 | 2篇 |
1971年 | 7篇 |
1970年 | 5篇 |
1968年 | 3篇 |
1967年 | 2篇 |
排序方式: 共有523条查询结果,搜索用时 31 毫秒
81.
目的了解急性呼吸窘迫综合征(ARDS)患儿急性期血清胆碱酯酶(CHE)、前白蛋白(PA)变化特点及临床意义,探讨CHE及PA变化及对预后的影响。方法51例的ARDS患儿分为未愈,死亡组(16例)与治愈/存活组(35例),设同龄普通肺炎对照组患儿30例,全部于入组当天及患ARDS最重时分别检测血清CHE、血气分析、肝功能其他各项指标,41例同时检测血清PA。结果未愈,死亡组ARDS患儿于入组时及最重时血清CHE及PA均显著低于治愈/存活组(人组时均P〈0.05,最重时均P〈0.01),氧合指数(PaOJFiO:)亦显著较低(均P〈0.05)。与正常儿童比较,两组的血清CHE、PA以及氧合指数均显著较低(均P〈0.01)。结论ARDS患儿急性期存在不同程度的血清CHE、PA及氧合指数降低,血清CHE、PA及氧合指数在一定程度上体现ARDS患儿病情的危重程度,对判断ARDS患儿预后有参考价值。 相似文献
82.
目的 探讨血清胆碱酯酶(CHE)活性在老年重症社区获得性肺炎患者中的变化及临床意义.方法 检测重症肺炎组、普通肺炎组和健康对照组血清CHE活性, 将他们按性别分为男女两组,再分别比较男性、女性组中重症肺炎组、普通肺炎组和健康对照组血清CHE活性.结果 男性组血清CHE活性:重症肺炎组<普通肺炎组<健康对照组(P<0.01);女性组血清CHE活性:重症肺炎组<普通肺炎组<健康对照组(P<0.01).结论 老年重症社区获得性肺炎患者血清胆碱酯酶活性降低,降低程度与肺部炎症的严重程度密切相关. 相似文献
83.
目的探讨慢性肝病患者血清胆碱酯酶(ChE)、前白蛋白(PAB)测定的临床意义。方法测定75例慢性肝病患者和55例健康人的血清ChE、PAB水平,并按临床分型进行分组比较,对慢性肝炎中度组患者进行治疗前后的对比。结果除慢性肝炎轻度组外,其余各组慢性肝病患者ChE与对照组差异具有非常显著意义(P〈0.001)。各组慢性肝病患者PAB与对照组差异具有非常显著意义(P〈0.001),慢性肝炎(轻、中、重)各组ChE、PAB的均数差别有高度显著性(P〈0.01)。结论血清ChE、PAB可作为慢性肝病病变程度的指标,对慢性肝病的疗效观察厦预后判断有重要的意义。 相似文献
84.
火麻仁油对D-半乳糖致衰老小鼠学习记忆障碍的保护作用研究 总被引:1,自引:0,他引:1
目的:研究火麻仁油对D-半乳糖(D-gal)致衰老小鼠学习记忆能力的保护作用,并探讨其作用机制.方法:采用D-半乳糖诱导小鼠衰老模型,用跳台法、水迷宫法和Morris水迷宫法测定衰老小鼠学习记忆能力,检测小鼠脑组织丙二醛(MDA)含量和总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性及大脑皮层和海马组织中乙酰胆碱(Ach)含量和乙酰胆碱酯酶(AchE)、胆碱乙酰化转移酶(ChAT)活性,观察脑组织组织形态学变化.结果:火麻仁油(3、6和12 mL/kg)能明显延长跳台实验的跳台潜伏期,缩短错误次数;缩短水迷宫实验达到时间和减少错误次数;缩短Morris水迷宫实验逃避潜伏期和第1次到达原平台时间,增加穿越原平台次数和逗留时间;能显著增加脑组织中T-AOC、SOD、GSH-Px活性和降低MDA含量,增加大脑皮层和海马组织中Ach含量和AchE、ChAT活性,减轻脑组织损伤.结论:火麻仁油可显著改善D-半乳糖致衰老小鼠学习记忆能力,其机制可能与其提高脑组织抗氧化和清除自由基能力,增强中枢胆碱能神经系统功能有关. 相似文献
85.
目的探讨病毒性肝病患者血清PA、CHE、TBA的变化及其在临床诊断分型中的意义。方法采用HITACHI-7080型全自动生化分析仪检测65例健康对照者和236例各临床型的病毒性肝病患者的血清PA、CHE、TBA,其分为急性肝炎、慢性肝炎、重型肝炎和肝硬变患者。同时检测白蛋白(ALB)、丙氨酸转氨酶(ALT)、天冬氨酸转氨酶(AST)、r-谷氨酸转肽酶(r-GT或GGT)、总胆红素(TBIL)。结果各组肝病患者的血清PA、CHE明显低于对照组,TBA水平(慢性轻度肝炎组除外)显著高于正常对照组(P<0.05)。慢性肝炎患者血清PA、CHE含量与慢性肝炎发展阶段性相一致,在慢性重度肝炎与肝硬变阶段达最低水平。结论检测血清PA、CHE、TBA三项指标对于病毒性肝病早期诊断、动态观察及预后评估具有一定的理论和临床价值。 相似文献
86.
BACKGROUND:The aim of the present study is to describe the clinical correlates of hypotension and its associated outcomes in patients with acute organophosphorus poisoning(AOPP).METHODS:In this retrospective cohort study,we analyzed data pertaining to 871 patients with AOPP who were treated at two hospitals.Data from hypotensive and non-hypotensive patients were compared to identify clinical correlates of hypotension.We also evaluated the association between clinical parameters(including hypotension)and in-hospital mortality.RESULTS:The incidence of hypotension in AOPP patients was 16.4%.Hypotensive patients showed signifi cantly higher in-hospital mortality(1.1%vs.39.9%,P<0.001).Advanced age(odds ratio[OR]1.25,95%confi dence interval[CI]1.08–1.44),history of diabetes(OR 2.65,95%CI 1.14–5.96),and increased white blood cell count(OR 1.06,95%CI 1.03–1.09),plasma cholinesterase(OR 0.91,95%CI 0.84–0.94),plasma albumin(OR 0.88,95%CI 0.85–0.92),serum amylase(OR 1.01,95%CI 1.01–1.02),and blood pH(OR 0.64,95%CI 0.54–0.75)were signifi cantly associated with hypotension.After adjusting for potential confounders,hypotension was associated with increased in-hospital mortality(hazard ratio 8.77–37.06,depending on the controlled variables).CONCLUSIONS:Hypotension is a common complication of AOPP and is associated with increased in-hospital mortality.Advanced age,history of diabetes,and changes in laboratory parameters were associated with hypotension in AOPP patients. 相似文献
87.
Rivastigmine, a reversible cholinesterase inhibitor, approved as a remedy in Alzheimer's disease, was suggested as pretreatment against nerve agents poisoning. We evaluated the pharmacokinetic, pharmacodynamic, physiologic, cognitive and emotional effects of repeated rivastigmine in young healthy male adults, in a double blind, placebo controlled crossover trial. Three groups completed 3 treatment periods: 0, 1.5 and 3 mg twice a day, for a total of 5 intakes. Parameters monitored were: vital signs, ECG, laboratory tests, sialometry, visual accommodation, inspiratory peak flow, and cognitive function tests. Adverse reactions were mild. Peak blood levels and peak cholinesterase inhibition increased with repeated intakes, and high variability and non-linear pharmacokinetics were demonstrated. In addition, two cognitive functions were affected (perceptual speed and dynamic tracking). The complicated pharmacological profile and the high inter-personal variability limit the potential use of rivastigmine as pretreatment for war fighters and first responders. 相似文献
88.
本实验采用Ellman’s法检测胆碱酯酶(ChE)活性。硫胺素(VB_1)在试管内对小白鼠全血ChE的抑制曲线呈S型。其IC_(50)为1.95±0.14mM。DDVP的ChE抑制曲线形状同VB_1相似,但所需浓度很低。DDVP和VB_1对ChE的共同作用好似功能性交互作用。PAM-Ⅰ不能复活VB_1所抑制的ChE,同样浓度却能部分复活DDVP所抑制的ChE。分析VB_1对ChE的抑制可能属变构抑制。体内实验证明,给小鼠肌注50mg/kg,甚至200mg/kg的VB_1,并不抑制ChE。故推论VB_1配合PAM-Ⅰ解救DDVP急性中毒,有利无害。 相似文献
89.
Summary Cholinesterase (ChE) is transiently expressed in undifferentiated embryonic cells. In the chick limb bud ChE-activity was found in the apical ectodermal ridge and in the subridge mesenchyme. The reaction was localized in the perinuclear cisterna, in an extensive network of narrow profiles of endoplasmic reticulum (ER), and in the Golgi complexThe chondroblasts emerging from the subridge mesenenyme, also showed strong ChE-activity. During differentiation the enzyme first disappeared from the Golgi zone. Then, the narrow ChE-positive ER was successively replaced by ChE-negative extended rough ER characteristic for the differentiated chondrocyte.The myoblasts showed weak ChE-activity with the same ultrastructural localization as in other mesenchymal cells. After fusion the myotubes exhibited strong ChE-activity in the perinuclear cisterna and the developing sarcoplasmic reticulum. In later stages of myogenesis the myoblasts were closely attached to the myotubes and had lost their ChE-activity.During mitosis of ChE-positive cells, ChE-activity was retained in fragments of perinuclear cisterna and ER. In ChE-active mesenchymal cells and chondroblasts we observed specialized contact zones between ER and plasma membrane. ChE-active cisternae of ER run parallel to the plasma membrane with a gap of approximately 10–15 nm. We discuss a possible function of a cholinergic system during morphogenesis. 相似文献
90.
Accidental exposure to sarin: vision effects 总被引:4,自引:0,他引:4
Roy H. Rengstorff 《Archives of toxicology》1985,56(3):201-203
Two men were accidentally exposed to vapors of sarin, a cholinesterase inhibitor and extremely toxic nerve gas. Diagnosis
was confirmed by depressed cholinesterase activity, and fixed extremely miotic pupils. No other signs or symptoms developed
and neither man required treatment. Recovery to normal cholinesterase activity was gradual over a 90-day period. Pupillary
reflexes were not detectable until 11 days after exposure; the miotic pupils dilated slowly over a 30–45 day-period. Eye pain
and blurred vision did not occur; visual acuity and amplitude of accommodation were improved for several weeks. Other functions
not affected significantly were intraocular pressure, visual fields, color vision, heterophorias, and vergences. 相似文献