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991.
The results of Tc-99m-PMT imaging on 100 patients with various malignant and benign hepatic diseases verified histologically (73 hepatocellular carcinoma, 3 liver cell adenoma, 1 cholangiocarcinoma, 5 metastatic liver carcinoma, 2 liver cyst, 12 hemangioma, 1 fatty degeneration, 1 liver regeneration, 1 postoperative liver fibrosis and 1 liver cirrhosis) are reported. All lesions appeared as decreased radioactivity or "cold" defect region on early Tc-99m-PMT imaging, rendering it valuable for the diagnosis of tumor localization. In 92 (95.8%) of the 96 patients with various hepatic tumors and 25 (86.2%) of the 29 patients with small hepatocellular carcinoma (less than 5 cm), the tumors were localized by early Tc-99m-PMT imaging. In 14 of the 73 patients with established hepatocellular carcinoma, the tumors gave greater radioactivity than that of the surrounding liver tissues, whereas in 31 patients the radioactivity of the tumor equalled the normal liver on delayed Tc-99m-PMT imaging (positive rate 61.6%). There was no significant difference between the positive rates of serum AFP level and the tumor size shown by delayed Tc-99m-PMT imaging in hepatocellular carcinomas. The radioactivity in 3 liver cell adenoma patients was similar to the gallbladder. No false positive result was seen in the other malignant and benign hepatic tumors. This study indicates that delayed Tc-99m-PMT imaging is highly specific in the diagnosis of hepatocellular carcinoma. 相似文献
992.
N Iu Korukhov A A Pisarevski? Iu A Lots G E Tsimarkina Z A Perminova 《Meditsinskaia tekhnika》1988,(3):43-46
The article describes four design variants of the "auxiliary liver" apparatus which consists of the blood passage fractionators or plasma filters and an original mass transfer device. Indications for using this or that variant of the apparatus have been determined in relationship to the patient's weight and concomitant complications. Clinical examples are given. 相似文献
993.
本文定义了一类“近乎双线性”系统。可用以近似一类奇异摄动双线性系统,而且可以描述某些实际工业对象。并发现其控制器的设计较方便。文中还给出了一种简单的反馈控制器的设计方法。又对一类多输入双线性系统,提出一种设计反馈控制器的改进方案,根据Lyapunov定理得到一非线性反馈控制律。以上设计方法分别对某合成氨反应器作了应用研究,仿真结果表明了方法的有效性。 相似文献
994.
G C Coletta S Z Mansdorf S P Berardinelli 《American Industrial Hygiene Association journal》1988,49(1):26-33
A "round-robin" interlaboratory evaluation of a proposed American Society for Testing and Materials (ASTM) standard test method was conducted for measuring the resistance of chemical protective clothing materials to degradation by liquid chemicals. The objective of this project was to determine the relative precision of the method and, where appropriate, recommend modifications that would improve reliability. In the round-robin format, eight laboratories used the proposed method to test each of five protective clothing materials against five liquid chemicals that are widely used commercially. The resulting data revealed that the proposed test method was not stringent enough to generate acceptable levels of accuracy and precision. Both intra- and interlaboratory standard deviations showed a high degree of variability in changes for the three physical properties evaluated. Changes in the method were identified which, if implemented, should improve accuracy and precision considerably. 相似文献
995.
996.
Headaches in civil servants: effect on work and leisure 总被引:1,自引:0,他引:1
Headaches in a group of civil servants and their effects on work and leisure activities, the medication taken, and numbers consulting their general practitioners during a year were assessed by a self administered questionnaire sent to 1000 civil servants in sections of a government department in London. The response rate was 74.7%. Altogether 77% of the respondents reported having had headaches in the previous 12 months. There was a higher prevalence in women (88%) than men (70%) and a significant decrease with increasing age. Women also had more frequent and severe headaches than men: 34% reported that headaches had interfered with work, either by impaired performance, making them leave work early, or by stopping them coming into work. About half of those who reported having severe headaches denied that they had affected their work, indicating difficulty in interpreting the term "severe." Nevertheless, 22% said that headaches interfered with their leisure activities as well as work which may be regarded as further evidence that the condition was truly disabling. Eighty per cent of those with headaches took medication, but within the past year only 11% had consulted their general practitioner and only 2.2% had been referred for further specialist opinion. Of the 22% who had not had a headache during the previous 12 months, 5.6% had never had a headache. In this group there was a larger proportion of men, a higher proportion with increasing age, and a higher proportion in non-desk working grades. Differentiation of the causes of headaches was not attempted in this survey but it is concluded that the extent to which they interfere with work and leisure is an important guide to their severity. It is suggested that the occupational health services may have an important role in assessing the causes of headaches and instituting preventive measures that benefit both the worker and industry. 相似文献
997.
P. E. Light Z. Y. Sahaf S. J. Publicover 《Naunyn-Schmiedeberg's archives of pharmacology》1988,338(4):339-344
Summary The effect of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) on the release of transmitter at the frog neuromuscular junction has been investigated electrophysiologically. TPA (100 nmol/l) caused a gradual rise in miniature end-plate potential (MEPP) frequency. After 20–30 min MEPP frequency had risen by approximately 40%. This action of the drug was not inhibited by bathing preparations in either Ca2+-free medium (0 Ca2+-1 mmol/l EGTA) or high Mg2+ medium, or by pretreatment with verapamil (5 mol/l). The inactive TPA analogue 4--TPA had no effect on release rate. There was no indication of any positive correlation between resting MEPP frequency and the size of the subsequent response to TPA treatment. Any synergism between [Ca2+]i and TPA treatment is therefore likely to occur at a site other than that which determines spontaneous release rate.The stimulatory effect of TPA was enhanced 2-fold by carrying out the experiments in a partially depolarising saline (10 mmol/l K+). When TPA was applied to preparations bathed in Ca2+-free depolarising saline, the response to the drug was still significantly greater than that in non-depolarised preparations. It is concluded that responsiveness to TPA is enhanced by depolarisation, but that little, if any, of this enhancement can be attributed to the consequent influx of Ca2+.Send offprint requests to S. J. Publicover at the above addressPEL was in receipt of an S.E.R.C. postgraduate awardZYS was in receipt of financial support from Umm Al Qura University, Saudi Arabia 相似文献
998.
Two new diterpenoid alkaloids, flavamine ( 1) and flavadine ( 2), were isolated from the roots of ACONITUM FLAVUM Hand-Mazz. The structures were established on the bases of spectral analyses and chemical correlations with napelline ( 3) and lucidusculine ( 4), respectively. 相似文献
999.
目的 探讨颈动脉斑块患者发生前循环缺血性卒中的临床及多模态超声(multimodal ultrasound, MMU)影响因素,构建基于超微血流成像技术(superb microvascular imaging, SMI)的风险分层预测模型。方法 回顾性分析颈动脉斑块患者683例,根据临床表现和多层螺旋电子计算机断层扫描(computed tomography, CT)/核磁共振扫描(magnetic resonance imaging, MRI),分为前循环卒中组(n=301)和非前循环卒中组(n=382)。收集患者颈动脉斑块的MMU特征、临床和实验室检查数据,采用多因素二元Logistic回归分析筛选出前循环缺血性卒中的影响因素。构建列线图风险预测模型,进行模型验证与风险分层。结果 前循环卒中组和非前循环卒中组年龄、体重指数(body mass index, BMI)、饮酒史、吸烟史、脑梗死既往史、高血压、糖尿病、低密度脂蛋白(low-density lipoprotein, LDL)、高密度脂蛋白(high-density lipoprotein, HDL)、同型半胱氨酸(hom... 相似文献
1000.
背景 近年来,国内针对多病共存患者在分级诊疗背景下就医机构选择行为的研究较少,研究多病共存患者的就医机构选择行为有重要的现实意义。目的 以分级诊疗为视角,分析多病共存患者就医机构选择行为及其影响因素,为进一步落实分级诊疗制度和合理配置医疗资源提供研究参考。方法 采用随机抽样法,选取2019-06-01至2020-01-01在上海市杨浦区中心医院医疗联合体(上海市杨浦区中心医院和上海市杨浦区定海、延吉、长白社区卫生服务中心)就诊的多病共存患者为研究对象。采用自设问卷对其进行调查,收集多病共存患者的一般资料,了解其对分级诊疗政策的认知情况及实际遵守情况、在不同疾病控制状况下至社区卫生服务中心首诊的意愿,以及其选择就诊医疗机构时考虑的因素等。采用二分类Logistic回归分析多病共存患者此次因病就医是否选择至社区卫生服务中心首诊的影响因素。结果 共发放1 100份问卷,回收有效问卷1 072份,有效问卷回收率为97.45%。1 072例多病共存患者中,老年(≥60岁)多病共存患者占85.07%(912/1 072)。624例(58.21%)患者表示知晓分级诊疗制度;940例(87.69%)患... 相似文献