全文获取类型
收费全文 | 1494篇 |
免费 | 59篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 56篇 |
妇产科学 | 34篇 |
基础医学 | 134篇 |
口腔科学 | 19篇 |
临床医学 | 174篇 |
内科学 | 186篇 |
皮肤病学 | 69篇 |
神经病学 | 105篇 |
特种医学 | 152篇 |
外科学 | 287篇 |
综合类 | 59篇 |
预防医学 | 75篇 |
眼科学 | 44篇 |
药学 | 81篇 |
1篇 | |
中国医学 | 5篇 |
肿瘤学 | 77篇 |
出版年
2022年 | 8篇 |
2021年 | 12篇 |
2019年 | 11篇 |
2018年 | 10篇 |
2017年 | 12篇 |
2016年 | 19篇 |
2015年 | 49篇 |
2014年 | 65篇 |
2013年 | 46篇 |
2012年 | 30篇 |
2011年 | 51篇 |
2010年 | 50篇 |
2009年 | 48篇 |
2008年 | 55篇 |
2007年 | 57篇 |
2006年 | 60篇 |
2005年 | 62篇 |
2004年 | 46篇 |
2003年 | 50篇 |
2002年 | 72篇 |
2001年 | 42篇 |
2000年 | 43篇 |
1999年 | 49篇 |
1998年 | 24篇 |
1997年 | 19篇 |
1996年 | 25篇 |
1995年 | 31篇 |
1994年 | 37篇 |
1993年 | 18篇 |
1992年 | 18篇 |
1991年 | 20篇 |
1990年 | 24篇 |
1989年 | 25篇 |
1988年 | 31篇 |
1987年 | 23篇 |
1986年 | 24篇 |
1985年 | 36篇 |
1984年 | 17篇 |
1983年 | 16篇 |
1981年 | 21篇 |
1980年 | 13篇 |
1979年 | 17篇 |
1978年 | 17篇 |
1977年 | 9篇 |
1975年 | 7篇 |
1974年 | 9篇 |
1970年 | 14篇 |
1967年 | 9篇 |
1939年 | 6篇 |
1930年 | 7篇 |
排序方式: 共有1561条查询结果,搜索用时 31 毫秒
61.
62.
63.
64.
Over an average span of one year, we performed a prospective clinical and immunologic evaluation of 30 patients with hemophilia. No patient developed life-threatening opportunistic infection or malignancy; however, the immunologic abnormalities and lymphadenopathy initially present in nine patients (lymphadenopathy group) persisted. In addition, five patients, representing 24% of the initial group without lymphadenopathy, developed generalized lymphadenopathy (converter group). One episode of idiopathic thrombocytopenia (ITP) and one episode of staphylococcal sepsis occurred in this "converter" group; one episode of ITP also occurred in the lymphadenopathy group. Sixteen patients remained asymptomatic. At the time of the follow-up evaluation, those differences in mononuclear cell (MNC) percentages and numbers noted initially among the three hemophiliac groups were no longer present. Natural killer cell function alone or in the presence of biologic response modifiers was not different among hemophiliac and control groups. Before developing lymphadenopathy, the converter group of patients had significantly better lymphocyte mitogenic function than did the other two groups of patients with hemophilia. However, lymphocyte mitogenic responses of all groups of patients with hemophilia significantly deteriorated over the course of the study. The abnormal mitogenic responses noted in these patients was explained in part by higher levels of spontaneous suppressor cell activity in mononuclear cell preparations from patients with hemophilia. We conclude that long-term immunologic studies of this patient population requires both quantitative and qualitative evaluations. Our data show that patients with hemophilia have progressive dysfunction of cell- mediated immunity. 相似文献
65.
Breast cancer is the most common cause of cancer death in women in this country. Until recently, the traditional treatment has been radical surgery with or without radiation therapy for patients with primary breast cancer, and palliative endocrine therapy followed by chemotherapy for patients with advanced disease. These treatments have met with limited effectiveness in terms of eradicating the disease. Studies in the past decade have given cause for optimism for breast cancer patients. Adjuvant systemic therapy after local treatment appears promising for certain subsets of patients with primary breast cancer. The development of estrogen receptor assays has markedly changed our approach to the disease and improved patient care. Estrogen receptor is an important prognostic factor and is useful in planning appropriate therapy for patients with primary breast cancer as well as those with advanced disease. Further research is urgently needed to improve the dismal survival of certain women with this common malignancy. 相似文献
66.
P. Sebastian U. Mackenstedt M. Wassermann E. Wurst K. Hartelt T. Petney M. Pfäffle N. Littwin J.L.M. Steidle P. Selzer S. Norra D. Böhnke R. Gebhardt O. Kahl H. Dautel Dr. R. Oehme 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2014,57(5):549-556
Ticks and tick-borne diseases are of great significance for the health of humans and animals. However, the factors influencing their distribution and dynamics are inadequately known. In a project financed by the Baden-Württemberg Ministry of the Environment, Climate and Energy Industry, as part of the program BWPLUS, interdisciplinary specialists work together to determine the influence of weather, (micro)climate, habitat, land use, human activities, and the population dynamics of host animals on the distribution and abundance of ticks and the diseases that they transmit in Baden-Württemberg. The project comprises four modules: the large-scale distribution of ticks in Baden-Württemberg (module 1), detailed studies of host–tick–pathogen interaction in relation to the microclimate (module 2), and the spatial occurrence of important tick-borne pathogens (module 3). The fourth module involves the comprehensive analysis and synthesis of all data in order to determine the relative importance of the factors studied and to develop a risk model. Recently, intensive investigations into tick control have been undertaken using various entomopathogenic fungi and nematodes as well as a parasitoid wasp. Our aim was to determine whether these natural enemies could be used to effectively reduce the number of free-living ticks. 相似文献
67.
68.
Melissa Jehn Andreas Gebhardt Uta Liebers Bahar Kiran Dieter Scherer Wilfried Endlicher Christian Witt 《Lung》2014,192(4):619-624
Background
Summer heat waves with temperature extremes are becoming more frequent with growing numbers in morbidity and mortality in patients with respiratory diseases. The aim of this study was to evaluate the ramifications of heat stress (temperature >25 °C) on the health status of patients with pulmonary arterial hypertension (PAH).Methods
Fifteen patients with PAH (mean age = 66.7 ± 5.2 years) continuously wore an accelerometer from April 1 to September 30, 2011, and their daily step count was recorded. In addition, patients kept a diary to record data on seven standardized questions regarding their daily symptoms. Echocardiography, 6-minute walk test, NTproBNP, and Modified Medical Research Council Scale (MMRC) were assessed at baseline and at the end of the study after 6 months.Results
On heat-stress days, patients showed significantly more symptoms and lower total steps/day compared to thermal comfort days (3,995 ± 2,013 steps/day vs. 5,567 ± 2,434 steps/day, respectively; P < 0.001). There was a significant negative correlation between total steps/day and Tempmax (R = ?0.47; P < 0.001) and humidity (R = ?0.34; P < 0.001). A significant positive correlation was found between daily symptoms and Tempmax (R = +0.79; P < 0.001) and humidity (R = +0.23; P < 0.001).Conclusions
Heat stress is associated with a compromised clinical status in patients with PAH. Adaptation strategies must be implemented to prevent heart-related morbidity, including therapeutic adjustments and adequate room cooling in the patient’s home and at the hospital. 相似文献69.
目的 探讨多房棘球绦虫(Em)重组BCG-EmⅡ/3疫苗免疫和Em原头节攻击后小鼠脾细胞因子的变化.方法 将Balb/c小鼠按体质量随机分为3组:疫苗皮下注射组、疫苗鼻腔内接种组、对照组.免疫后8周用Em原头节进行攻击感染,感染后18周杀鼠取脾,分离脾细胞,分别用原液、Em抗原(EmAg)、刀豆蛋白A(ConA)或植物血凝素(PHA)培养,酶联免疫吸附(ELISA)法检测脾细胞培养上清液中白细胞介素2(IL-2)、γ干扰素(IFN-γ)、肿瘤坏死因子α(TNF-β)、白细胞介素4(IL-4)水平.结果 疫苗皮下注射组原液培养条件下IL-2、IFN-γ、TNF-α和IL-4水平分别为(34.6±2.7)、(34.5±2.8)、(265.0±0.0)、(9.8±2.6)ng/L,与对照组[(25.0±1.9)、(30.0±0.0)、(10.0±0.0)、(12.5±2.7)ng/L]比较差异均有统计学意义(P<0.01或<0.05);疫苗鼻腔内接种组原液培养条件下上述4种指标分别为(32.5±2.2)、(33.6±2.7)、(130.0±0.0)、(10.4±2.7)ng/L.与对照组比较差异均有统计学意义(P<0.01或<0.05);疫苗皮下注射组原液培养条件下TNF-α水平明显高于疫苗鼻腔内接种组(P<0.01).EmAg、ConA(或PHA)刺激培养条件下,上述4种指标明显高于相同组别的原液培养(P<0.01),且ConA(或PHA)刺激培养条件下,上述4种指标明显高于相同组别的EmAg刺激培养条件(P<0.01).结论 多房棘球绦虫重组BCG-EmⅡ/3疫苗诱导小鼠产生辅助T淋巴细胞(Th)1型免疫反应,从而对抗Em原头节攻击感染. 相似文献
70.
[目的]观察胃底折叠术治疗胃食管反流病对高血压的影响。[方法]回顾性分析2011-06—2012-08期间20例行腹腔镜胃底折叠术的胃食管反流病合并高血压患者的临床资料,依照反流病诊断问卷在手术前和手术后进行反流症状评分。[结果]20例均成功实施腹腔镜手术并于术后第12个月随访。反流总积分(Sc)由术前20.0±9.5降至术后0.5±0.9(P0.05),术后收缩压下降了(11.0±12.0)mm Hg(1mmHg=0.133kPa),舒张压下降了(9.0±11.5)mm Hg(均P0.05)。术后随访12个月11例血压恢复正常,停药时间均在9个月以上;2例减少2种降压药,1例减少1种降压药;6例无效,仍用术前降压药物。[结论]胃食管反流病与部分高血压密切相关,腹腔镜胃底折叠术治疗胃食管反流病合并高血压安全、有效。 相似文献