全文获取类型
收费全文 | 528篇 |
免费 | 27篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 31篇 |
妇产科学 | 5篇 |
基础医学 | 61篇 |
口腔科学 | 2篇 |
临床医学 | 50篇 |
内科学 | 86篇 |
皮肤病学 | 7篇 |
神经病学 | 35篇 |
特种医学 | 146篇 |
外科学 | 40篇 |
综合类 | 31篇 |
预防医学 | 27篇 |
眼科学 | 2篇 |
药学 | 24篇 |
中国医学 | 3篇 |
肿瘤学 | 15篇 |
出版年
2022年 | 1篇 |
2021年 | 6篇 |
2020年 | 3篇 |
2019年 | 7篇 |
2018年 | 12篇 |
2017年 | 4篇 |
2016年 | 8篇 |
2015年 | 10篇 |
2014年 | 11篇 |
2013年 | 28篇 |
2012年 | 10篇 |
2011年 | 13篇 |
2010年 | 18篇 |
2009年 | 21篇 |
2008年 | 21篇 |
2007年 | 20篇 |
2006年 | 13篇 |
2005年 | 9篇 |
2004年 | 10篇 |
2003年 | 11篇 |
2002年 | 8篇 |
2001年 | 8篇 |
2000年 | 6篇 |
1999年 | 10篇 |
1998年 | 44篇 |
1997年 | 33篇 |
1996年 | 19篇 |
1995年 | 18篇 |
1994年 | 14篇 |
1993年 | 15篇 |
1992年 | 4篇 |
1991年 | 3篇 |
1990年 | 12篇 |
1989年 | 12篇 |
1988年 | 11篇 |
1987年 | 12篇 |
1986年 | 15篇 |
1985年 | 19篇 |
1984年 | 7篇 |
1983年 | 7篇 |
1982年 | 11篇 |
1981年 | 7篇 |
1980年 | 9篇 |
1979年 | 2篇 |
1978年 | 9篇 |
1977年 | 7篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1973年 | 1篇 |
排序方式: 共有566条查询结果,搜索用时 333 毫秒
51.
A history of pet contact and/or apparent clinical sensitivity was obtained in 65 (55%) of 118 unselected asthmatic children. These 65 children were skin tested and their sera examined for specific IgE using the radioallergosorbent test. Those children who had apparent clinical sensitivities had larger skin test reactions and were more likely to have positive specific IgE results than those without apparent sensitivities. Positive skin tests were very common (80%), but the larger the skin test reaction (weal diameter greater than 4 mm diameter) the more likely was there to be a positive history or a positive specific IgE result. Hence a large skin test reaction can provide a helpful pointer to animal allergy of clinical importance. Commercially available animal extracts have limitations for diagnostic tests. A questionnaire survey of 150 day schools emphasized the potential opportunities for contact with animal allergens at school. 相似文献
52.
Two sports-related knee injuries resulted in small fractures at the posteromedial corner of the tibial plateau. Magnetic resonance imaging demonstrated findings consistent with an avulsion injury at the semimembranosus insertion, as well as a similar pattern of internal derangement in both cases. 相似文献
53.
Pasquale Perrone-Filardi MD ; Luigi Corrado MD ; Gregorio Brevetti MD ; Antonio Silvestro MD ; Santo Dellegrottaglie MD ; Maria Cafiero MD ; Gianluca Caiazzo MD ; Andrea Petretta MD ; Antonio Maglione MD ; Cinzia Monda MD ; Giuseppina Guerra MD ; Antonio Marzano MD ; Paolo Cesarano MD ; Paola Gargiulo MD ; Massimo Chiariello MD 《Journal of clinical hypertension (Greenwich, Conn.)》2009,11(5):260-265
Endothelial dysfunction is a major determinant of atherosclerosis and a negative prognostic factor in patients with coronary artery disease and hypertension. Recovery of endothelial dysfunction has been associated with improved prognosis in these patients. The aim of the present study was to verify whether antagonism of angiotensin II AT1 receptors with an angiotensin receptor blocker, candesartan, improved endothelial function in patients with hypertension, stable coronary artery disease, and endothelial dysfunction. We studied 26 patients who were receiving β-blockers with optimal blood pressure control, in a randomized, double blind study. Patients were randomized to placebo (n=13) or to candesartan 16 mg/d (n=13) for 2 months. Endothelial function was assessed by ultrasound using hyperemic flow-mediated dilation of the brachial artery. Mean arterial blood pressure was unchanged in both groups (from 93.3±9.2 to 93.2±17.3 mm Hg in the candesartan group and from 101.3±14.2 to 102.3±13.9 mm Hg in the placebo group; both P =ns). Maximal blood flow was similar between placebo and candesartan groups at baseline and at the end of the study, whereas flow-mediated dilation significantly increased in the candesartan group (from 5.27%±1.69% to 7.15%±2.67%; P =0.01) but remained unchanged in the placebo group (from 4.49%±1.97% to 5.88%±2.30%; P =ns). AT1 receptor antagonism with candesartan, in addition to β-blocker therapy, improves endothelial function in high-risk hypertensive patients. 相似文献
54.
55.
56.
目的:测定炎痛净乳膏中双氯芬酸钠和苯佐卡因的含量。方法:高效液想象以谱法,甲醇为提取溶剂,地西泮为内标,No-va-PakC18色谱柱,甲醇-水-冰醋酸(80:20:0.5)为流动相,检测波长为283nm。结果:双氯芬酸钠和苯佐卡因在5μg/ml-40μg/ml范围内,其浓度与峰面积均呈良好的线性关系(r=0.9999),平均回收率分别为101.0%,RSD=1.21%,99.8%,RSD=0.62%。结论:本法专属性强,操作简便,结果准确。 相似文献
57.
We report two cases of sleep disturbances and perceptual disorder appearing in close temporal relationship with initiation of flunarizine therapy for migraine prophylaxis: these side effects disappeared after therapy interruption; resumption of the drug in one case was associated with symptom recurrence. 相似文献
58.
59.
H-2-restricted cytotoxic effectors generated in vitro by the addition of trinitrophenyl-conjugated soluble proteins 总被引:3,自引:3,他引:3
下载免费PDF全文
![点击此处可从《The Journal of experimental medicine》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A Schmitt-Verhulst CB Pettinelli PA Henkart JK Lunney GM Shearer 《The Journal of experimental medicine》1978,147(2):352-368
Murine spleen cells from normal donors were cultured in vitro with trinitrobenzene sulfonate (TNBS)-conjugated soluble proteins, i.e., bovine gamma globulin (TNP-BGG) or bovine serum albumin (TNP-BSA). Addition of 100 μg of any of these TNP-proteins to the spleen cell cultures led to the generation of cytotoxic T-cell effectors which were H-2-restricted and TNP- specific. The lytic potential of such effectors was comparable to that generated by sensitization with TNBS-modified syngeneic cells, and was restricted to haplotypes shared at the K or K plus I-A, or the D regions of the H-2 complex. Greater effecter cell activity was generated by addition of TNP-BGG against TNBS-modified targets which shared K plus I-A than against modified targets which shared the D region with the responding cells, which suggests that the same immune response genes are involved when the response is generated by the addition of TNP-conjugated soluble proteins or of TNBS- modified cells. H-2-restricted, TNP-specific effecter cells were generated by culturing mouse spleen cells with syngeneic cells which had been preincubated with TNP- BGG or TNP-BSA for 1.5 h. The addition of unconjugated soluble proteins to the cultures did not result in cytotoxic effectors detectable on H-2-matched targets, whether the targets were prepared by modification with TNBS, or by incubation with either the unconjugated or TNP-conjugated proteins. Depletion of phagocytic cells in the tumor preparation by Sephadex G-10 column fractionation before incubation with TNP-BSA had no effect on their lysis by the relevant effector cells. Immunofluorescent staining of tumor target cells with anti-TNP antibodies indicated that TNP could be detected on the tumor cells within 10 rain of incubation with TNP-BSA. The cytotoxic response generated by addition of the TNP-proteins to spleen cell cultures was found to be T-cell dependent at the effector phase, as shown by the sensitivity of the lytic phase to absorbed RAMB and complement. Furthermore, the response did not appear to be attributable to antibody-dependent cellular cytotoxicity. Three mechanisms were considered which could account for the generation of H-2-restricted, TNP-specific, cytotoxic T-cell effectors by the addition of soluble TNP-proteins. These include covalent linkage of activated TNP groups from the soluble proteins to cell surface components, macrophage processing of the soluble conjugates and presentation to the responding lymphocytes in association with H-2-coded self structures, or hydrophobic interaction of the TNP-proteins to cell surfaces. Results obtained from sodium dodecyl sulfate gel patterns indicating that cell-bound TNP was still linked to BSA, and the observation that phagocytic-depleted cells could interact with the soluble TNP-proteins and function as H-2-restricted targets, appear not to favor the first two proposed mechanisms. 相似文献
60.
脑出血大鼠脑组织膜型基质金属蛋白酶、基质金属蛋白酶2和基质金属蛋白酶9表达及益气活血中药的干预效应 总被引:1,自引:0,他引:1
目的:观察益气活血中药对脑出血大鼠脑组织中膜型基质金属蛋白酶、基质金属蛋白酶2和基质金属蛋白酶9表达量的影响,从脑出血损伤区微血管系统重建的角度,探讨益气活血中药治疗脑出血的作用机制。方法:实验于2006-03/10在中南大学湘雅医院中西医结合研究所实验室完成。实验材料:补阳还五汤全方(黄芪,当归,赤芍,红花,川芎,地龙,桃仁按20∶3∶3∶3∶2∶3∶3的比例);补阳还五汤益气成分(黄芪按上述比例);补阳还五汤活血成分(当归,赤芍,地龙,川芎,桃仁,红花按3∶3∶3∶2∶3∶3的比例)。用蒸馏水两次水煎,分别浓缩为1.54,0.81和0.73g/mL。实验分组:155只SD大鼠随机分为正常对照组、假手术组、模型组、益气活血组、益气组、活血组。正常对照组5只大鼠,其余每组30只,再随机分为术后灌胃2,4,7,14,21,28d6个观察时间点,各个时间点5只大鼠。实验干预:造模:采用立体定位技术将胶原酶Ⅶ注入大鼠大脑右苍白球制成脑出血大鼠模型。假手术组大鼠仅注入2μL生理盐水,其余手术过程相同。给药:正常对照组:普通饲养,自由饮水;假手术组和模型组术后予蒸馏水灌胃2次/d,2mL/次;益气活血组、益气组、活血组分别给予补阳还五汤全方、补阳还五汤益气成分、补阳还五汤活血成分30.80,16.20,14.60g/(kg·d)(按体表面积计算为临床70kg成人剂量的3倍)灌胃,2次/d,2mL/次。各组大鼠分别于灌胃2,4,7,14,21,28d麻醉下取脑,制备切片;正常组动物于28d处死。实验评估:免疫组织化学染色方法检测各组灌胃不同时间脑组织基质金属蛋白酶2、基质金属蛋白酶9和膜型基质金属蛋白酶的阳性微血管数。结果:155只大鼠均进入结果分析。①正常组、假手术组皮质偶见膜型基质金属蛋白酶、基质金属蛋白酶2和基质金属蛋白酶9表达。②模型组膜型基质金属蛋白酶、基质金属蛋白酶2呈双峰表达,4d为最高峰,至14~21d再有小高峰出现。③益气活血组给药4d时,膜型基质金属蛋白酶、基质金属蛋白酶2为表达低谷,低于模型组(P<0.01)、益气组和活血组(P<0.05);在中后期,益气活血组膜型基质金属蛋白酶表达高峰为7~14d,较模型组提前出现,21d后与模型组比,各治疗组膜型基质金属蛋白酶已表达极少(P<0.01);益气活血组基质金属蛋白酶2在7d后一直呈高水平维持,高于其他各组(P<0.05),28d后开始逐渐下降。④模型组基质金属蛋白酶9在造模后4d达最高峰(P<0.01),两周后几乎无表达。益气活血组基质金属蛋白酶9高峰推迟至7d出现(P<0.05),之后逐渐下降。结论:益气活血中药可通过调节脑出血后膜型基质金属蛋白酶、基质金属蛋白酶2和基质金属蛋白酶9表达,改善出血后脑组织的微环境,有利于微血管系统重建,促进组织修复。 相似文献