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1.
Using JEG-3 and BeWo cells, we examined the effect of “real life” mixtures of polycyclic aromatic hydrocarbons (PAHs), at doses reported in maternal blood (Mix I) and in placental tissue (Mix II), on human chorionic gonadotropin (hCG), placental lactogen (hPL) and placental growth factor (hPLGF) secretion, protein expression and immunolocalization. Additionally, the action of PAH mixtures on basal and hormone-stimulated matrix metalloproteinase-2 (MMP-2), MMP-9 and vascular endothelial growth factor (VEGF) protein expression was evaluated. Under basal conditions, the PAH mixtures increased hCG and decreased hPLGF levels in both cell lines, while hPL expression was stimulated in JEG-3 and inhibited in BeWo. There was no effect on the MMP-2/MMP-9 ratio or VEGF expression. In hormone-stimulated cells, PAH mixtures changed the MMP-2/MMP-9 ratio in JEG-3 cells in favor of MMP-9, while in BeWo MMP-2 was favored. The effect on VEGF expression was cell specific and dependent on the mixture. In hCG-treated cells, only Mix II inhibited VEGF expression in JEG-3 cells. Neither PAH mixtures affected this protein in BeWo cells. In hPL-treated cells, Mix I had a stimulatory effect in JEG-3 cells, while Mix II exerted an inhibitory effect in BeWo cells. In hPLGF-treated cells, Mix II decreased in JEG-3 cells, but in BeWo cells, both mixtures increased VEGF expression. Considering that the evaluated protein hormones play crucial roles in angiogenesis and neovascularization in the placenta, “real life” PAH mixtures by disrupting protein hormones levels, the MMP-2/MMP-9 ratio and VEGF expression can lead to insufficiency and many pregnancy-related disorders. 相似文献
2.
壮精合剂治疗围绝经期综合征58例 总被引:1,自引:0,他引:1
目的:探讨壮精合剂治疗围绝经期综合征的临床疗效。方法:选取符合围绝经期综合征诊断标准的病人58例,应用壮精合剂加减口服治疗1~2个月。结果:显效31例占53.4%;有效23例占39.7%;无效4例占6.9%,总有效率为93%。结论:壮精合剂治疗围绝经期综合征能收到良好的临床疗效。 相似文献
3.
K. Norpoth W. Stücker E. Krewet G. Müller 《International archives of occupational and environmental health》1988,60(3):163-168
Summary From preliminary experiments it was known that radiolabelled benzene and some of its metabolites during its metabolic activation process produce different in vitro DNA-phenyladducts in mitoplasts [5, 11].As we reported previously [9] at least one of these adducts, N-7-phenylguanine, is excreted in the urine of rats in measurable amounts, probably through an excision-repair mechanism after an inhalation experiment. Now we found, after i.p. application of benzene in the urine of rats, a compound separated by cation-exchange chromatography that behaves like a synthezised N-7-phenylguanine reference substance with respect to its retention index and the UV-absorption. This finding could be confirmed by HPLC-measurements with reversed-phase carrier materials. Silylation and gaschromatographic/mass spectrometric (GC/MS) separation of the fraction, which contains the phenylguanine, revealed that these fractions contain further phenyl adducts. Furthermore we studied the time-dependent excretion of the DNA-base adduct. Surprisingly the excretion dropped to zero on the fourth day and showed a new increase thereafter. 相似文献
4.
佛山市城区室内装修污染特征初探 总被引:8,自引:0,他引:8
目的 为了解佛山市室内装修空气污染状况,通过对佛山市室内装修污染物进行调查,掌握室内装修污染的一些基本特征并提出控制措施。方法 根据卫生部《室内空气质量卫生规范》以及《室内空气污染物的检验方法》方案,调查采用了问卷调查和现场检测的方法。结果 佛山市室内装修空气污染物主要为甲醛,苯,总挥发性有机物(TVOC),超标率分别为86%,36%,23%。结论 目前佛山市城区室内装修污染物的特征为:有机污染较无机污染严重,室内甲醛污染严重,苯次之而氢污染相对较轻,室内空气苯污染车辆、居室高于办公室,甲醛污染居室,办公室高于车辆。 相似文献
5.
A mixture of experts network structure for modelling Doppler ultrasound blood flow signals 总被引:1,自引:0,他引:1
Mixture of experts (ME) is a modular neural network architecture for supervised learning. This paper illustrates the use of ME network structure to guide modelling Doppler ultrasound blood flow signals. Expectation-Maximization (EM) algorithm was used for training the ME so that the learning process is decoupled in a manner that fits well with the modular structure. The ophthalmic and internal carotid arterial Doppler signals were decomposed into time-frequency representations using discrete wavelet transform and statistical features were calculated to depict their distribution. The ME network structures were implemented for diagnosis of ophthalmic and internal carotid arterial disorders using the statistical features as inputs. To improve diagnostic accuracy, the outputs of expert networks were combined by a gating network simultaneously trained in order to stochastically select the expert that is performing the best at solving the problem. The ME network structure achieved accuracy rates which were higher than that of the stand-alone neural network models. 相似文献
6.
取因职业而接触乙烯类或苯类的孕妇静脉血和他们新生儿脐带血进行SCE和MN测定。发现接触乙烯类或苯类的母血SCE(8.55±0.84,9.44±1.12)均高于对照组(7.68±1.40),他们新生儿脐带血SCE(8.94±1.43,8.75±0.88)也高于对照组(6.71±1.27)。接触乙烯类和苯类的母血微核率(0.833‰,0.727‰),高于对照组(0.267‰),他们新生儿脐血微核率(0.75‰,0.818‰)也高于对照组(0.267‰)。我们还发现母亲孕期被动吸烟增强了这两类诱变剂对他们后代的遗传毒性。 相似文献
7.
逍遥合剂的质量标准研究 总被引:2,自引:0,他引:2
目的:建立逍遥合剂的质量标准。方法;采用TLC法对处方中的白芍、甘草进行定性鉴别;用HPLC法测定芍药苷的含量。结果:在TLC色谱中均能检出白芍、甘草、芍药苷在0.3980-1.3930μg范围内呈良好的线性关系,r=0.9999,平均回收率为98.5%,RSD=0.83%。结论:所建立的方法可准确地进行定性,定量检测可用于该制剂的质量控制。 相似文献
8.
目的 :探讨急性有机磷中毒 (AOPP)死亡。方法 :回顾分析 1998年至 2 0 0 0年 8月死亡病例 4 6例 ,占同期中AOPP5 0 8例的 9.0 6 %。结果 :洗胃不彻底 15例 (32 .6 % ) ,阿托品用量不足 12例(2 6 .1% ) ;中间综合征 (IMS) 7例 (15 .2 % )阿托品中毒 5例 (10 .9% ) ;混合性中毒 3例 (6 .5 % ) ,其余存在严重并发症。结论 :表明洗胃不彻底 ,阿托品用量不足及中毒、IMS、混合性中毒是AOPP死亡的主要原因。对AOPP并发的紧急凶险症状未及时控制也是其死亡原因之一。 相似文献
9.
强兆艳 《天津医科大学学报》2001,7(1):45-47
目的:了解苯作业场所空气中苯浓度,推测苯作业发展趋势,方法:采用和平区1993-1999年39家工业企业,220个苯作业点,660个空气样品中的苯浓度值,按不同作业工种分为油漆组,化工(原料)组,粘胶组及印刷组,通过成组设计的多个样本比较的秩和检验进行分析。结果:1997年内不同作业组空气中苯平均浓度差异有显著性(H=8.00000 P<0.05),印刷组苯平均浓度高于其它作业组,其余年度中差异无显著性(P>0.05),1993-1999年,印刷组苯作业场所的苯平均浓度差异无显著性(P>0.05),结论:和平区苯作业开始由较低浓度过渡到较高浓度,以油漆业为主过渡到以印刷业为主,并且,1997年印刷组苯平均浓度超过国家卫生标准,应引起重视。 相似文献
10.
Ruth A. Etzel David L. Ashley 《International archives of occupational and environmental health》1994,66(2):125-129
Between March and November of 1991, approximately 9000 workers from 43 different countries battled the burning oil wells in Kuwait. To document the exposure of persons in Kuwait during the oil well fires to volatile organic compounds (VOCs), we obtained samples of blood from 14 U.S. personnel in Kuwait City in May of 1991 (group I) and 40 American firefighters working in the oil fields in October of 1991 (group II). Concentrations of VOCs in group I and group II were compared with those of a random sample of 114 persons in the United States (reference group). The median concentrations of VOCs in group I were equal to or lower than those in the reference group. We found significant differences between the median concentrations of several VOCs in group 11 and the reference group. Median levels of ethylbenzene were about 10 times higher among group II than among the reference group (0.53 g/I vs 0.052 g/l). Median levels of benzene, m-/p-xylene, o-xylene, styrene, and toluene among group II were more than double those of the reference group. Although firefighters had higher median concentrations of VOCs than the reference group, those American personnel in Kuwait not involved in fighting the oil fires had concentrations of VOCs comparable to those in the reference group. Blood VOC measurements indicate a significant increase in exposure to VOCs in firefighters, but do not demonstrate this in personnel in Kuwait City. 相似文献