全文获取类型
收费全文 | 56522篇 |
免费 | 3825篇 |
国内免费 | 959篇 |
专业分类
耳鼻咽喉 | 433篇 |
儿科学 | 1448篇 |
妇产科学 | 1440篇 |
基础医学 | 6955篇 |
口腔科学 | 886篇 |
临床医学 | 4961篇 |
内科学 | 13236篇 |
皮肤病学 | 885篇 |
神经病学 | 5370篇 |
特种医学 | 1981篇 |
外国民族医学 | 2篇 |
外科学 | 7203篇 |
综合类 | 2130篇 |
现状与发展 | 1篇 |
一般理论 | 2篇 |
预防医学 | 3241篇 |
眼科学 | 790篇 |
药学 | 4613篇 |
8篇 | |
中国医学 | 979篇 |
肿瘤学 | 4742篇 |
出版年
2023年 | 499篇 |
2022年 | 1199篇 |
2021年 | 1925篇 |
2020年 | 1229篇 |
2019年 | 1399篇 |
2018年 | 1620篇 |
2017年 | 1254篇 |
2016年 | 1297篇 |
2015年 | 1651篇 |
2014年 | 2201篇 |
2013年 | 2730篇 |
2012年 | 3788篇 |
2011年 | 3805篇 |
2010年 | 2221篇 |
2009年 | 2109篇 |
2008年 | 3226篇 |
2007年 | 3291篇 |
2006年 | 2994篇 |
2005年 | 2874篇 |
2004年 | 2599篇 |
2003年 | 2327篇 |
2002年 | 2133篇 |
2001年 | 1470篇 |
2000年 | 1388篇 |
1999年 | 1300篇 |
1998年 | 541篇 |
1997年 | 425篇 |
1996年 | 423篇 |
1995年 | 323篇 |
1994年 | 298篇 |
1993年 | 249篇 |
1992年 | 689篇 |
1991年 | 582篇 |
1990年 | 548篇 |
1989年 | 558篇 |
1988年 | 465篇 |
1987年 | 427篇 |
1986年 | 409篇 |
1985年 | 322篇 |
1984年 | 263篇 |
1983年 | 214篇 |
1982年 | 121篇 |
1979年 | 214篇 |
1978年 | 131篇 |
1977年 | 112篇 |
1974年 | 123篇 |
1973年 | 129篇 |
1972年 | 123篇 |
1971年 | 111篇 |
1969年 | 103篇 |
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
61.
Michael Robson Isabelle Côte Ian Abbs Geoffrey Koffman David Goldsmith 《American journal of transplantation》2003,3(3):324-327
Thrombotic microangiopathy is a rare but important finding in the context of organ transplantation. Acute renal insufficiency in the setting of hemolysis and thrombocytopenia, a triad that constitutes 'hemolytic uremic syndrome', can be associated with, or triggered by, conditions such as verocytotoxin-producing Escherichia coli, viral infections, malignant hypertension, scleroderma, allograft rejection, lupus erythematosus, pregnancy, and medications including mitomycin C, calcineurin inhibitors, and oral contraceptives. After renal transplantation, it can occur, as either a de novo episode, or recurrent disease. Calcineurin inhibitors have long been associated with post-transplantation thrombotic microangiopathy. Sirolimus has been used as a primary immunosuppressant in patients transplanted with a history of earlier hemolytic-uremic syndrome, and also as rescue therapy in patients with calcineurin-inhibitor-associated thrombotic microangiopathy. We describe four cases where there was significant thrombotic microangiopathy in the context of contemporaneous or contiguous calcineurin inhibitor and sirolimus usage. As the intrarenal cyclosporin concentration is thought to be significantly elevated when cyclosporin and sirolimus are used together, this may explain these findings, and mandates caution in their co-administration. 相似文献
62.
63.
Vincenzo Neri Antonio Ambrosi Giuseppe Di Lauro Tiziano Pio Valentino 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2006,10(1):66-69
OBJECTIVES: The aim of this study was to evaluate the safety and effectiveness of laparoscopic-assisted sigmoid colectomy for diverticulitis and to assess its postoperative advantages. METHODS: From 1999 to 2001, 5 patients were selectively operated on with a laparoscopic-assisted procedure for uncomplicated sigmoid diverticulitis. In the preceding period (September 1997 through December 1998), 4 patients underwent open procedures for the same pathology. The surgical indication with the same criteria was restrictive: at least 2 acute episodes had occurred that were treated with hospital admission and that were separated by an adequate period (2 months) of medical therapy. RESULTS: No conversions of laparoscopy to an open procedure were necessary. Age, sex, weight, morbidity, and mortality were similar between the 2 groups. Operative time was 180 minutes for laparoscopy and 120 minutes for laparotomy. Postoperative resumption of peristalsis was 24 hours versus 4 days, resumption of alimentation was on the second postoperative day versus the fifth postoperative day, and hospital stay was 7 days versus 12 days for laparoscopy and laparotomy, respectively. CONCLUSION: This study shows the feasibility and the advantages of elective laparoscopic-assisted colonic resection for uncomplicated sigmoid diverticulitis. The advantages of the laparoscopic approach are the lower need for analgesics and the more precocious ambulation, canalization, resumption of alimentation, and the shorter hospital stay. 相似文献
64.
Isabelle Mermet MD ; Nathalie Pottier MSc ; Jean Marie Sainthillier MSc ; Carole Malugani MSc ; Sandrive Cairey-Remonnay MD ; Stéphane Maddens PhD ; Didier Riethmuller MD PhD ; Pierre Tiberghien MD PhD ; Philippe Humbert MD PhD ; François Aubin MD PhD 《Wound repair and regeneration》2007,15(4):459-464
Amniotic membrane (AM), the most internal placental membrane, has unique properties including antiadhesive effects, bacteriostatic, wound protection and pain-reduction properties, as well as epithelialization initialization capacities. Furthermore, AM is widely available and less costly than other bioengineered skin substitutes. In a prospective pilot study, we evaluated the safety, feasibility, and the effects on healing of AM graft in 15 patients with chronic venous leg ulcers. AM grafts were prepared from placentas harvested during cesarean section. All grafted AM had adhered to the wound bed 7 days after being applied with a 100% engraftment rate. The percentage of granulation tissue increased significantly (from 17% on day 0 to 69% on day 14, p<0.0001), along with a significant decrease of fibrinous slough (from 36% at day 0 to 16% at day 14, p<0.001). A significant clinical response occurred in 12 patients (80%) including complete healing (20%) in three during the 3-month follow-up period. The ulcer surface area decreased significantly from a mean value (+/- standard deviation) of 4.59 +/- 2.49 cm(2) at baseline to 2.91+/-2.01 cm(2) on day 30 (p<0.001). All patients experienced a significant reduction of ulcer-related pain rapidly after AM transplantation. No adverse events were recorded. AM transplantation seems to function as a safe substrate, promoting proper epithelialization while suppressing excessive fibrosis. Further advantages of biotherapy with AM are its easy and low-cost production, and that it can be applied as an ambulatory treatment without immobilization. AM transplantation may thus be considered to be an alternative method for treating chronic leg ulcers. 相似文献
65.
Isabelle Durieu Evelyne Vericel Daniel Guichardant Hubert Roth Jean-Paul Steghens Jocelyne Drai Raphaele Nove Josserand Eric Fontaine Michel Lagarde Gabriel Bellon 《Journal of cystic fibrosis》2007,6(5):320-326
BACKGROUND: An imbalance in the ratio of arachidonic acid and docosahexaenoic acid (DHA) was found in cystic fibrosis (CF) affected tissues and was suggested to promote inflammation. Several studies have shown that the long chain n-3 fatty acids reduced inflammatory activity while others have highlighted prooxidant activity of DHA at high concentrations. The aim of our study was to evaluate the effects of an intravenous fish-oil emulsion enriched with n-3 FA in patients with CF on plasma and platelet FA composition and peroxidation markers. METHODS: 13 patients with CF received one IV emulsion per week of 2 mL/kg fish-oil n-3 emulsion for 12 weeks. RESULTS: There was a significant increase in 20:5 n-3 and 22:6 n-3 platelet FA composition, no variation in 20:4 n-6, a decrease in n-9. There was no variation in plasma FA composition. Specific urinary markers of lipid peroxidation derived from n-3 and n-6 showed a very high level before infusion compared with usual values in healthy subjects which was not affected by treatment. A significant weight loss and a decrease in reduced glutathione were observed in adult patients. CONCLUSIONS: The intravenous administration of n-3 FA in CF patients induced a significant modification in platelet FA composition but no modification of oxidative markers. However, the weight loss and the decreased level in reduced glutathione observed in adult patients may suggest a potential deleterious activity for some patients. Further studies are necessary to determine the optimal dose and route for long chain FA administration required to reach a potential beneficial effect. 相似文献
66.
F. Specchiulli R. Gabrieli D. Borsetti V. Di Carlo 《Journal of orthopaedics and traumatology》2007,8(3):123-127
We examined the clinical and radiographic results of 93 patients affected by knee arthritis or osteonecrosis subjected to
unilateral cementless mobile-bearing total knee arthroplasty with the LCS prothesis (Depuy/Johnson & Johnson). The mean follow-up
was 9.5 years (range, 7–12 years). Clinical evaluation was performed using the Knee Society rating system, while radiographic
evaluation was done according to the Knee Society roentgenographic system. At the latest follow-up, the mean knee score was
87 points: the functional score improved from 40 to 90. Radiolucent lines were small and not progressive. The implant survival
at 12 years was 88%. Six knees (7%) required revision for implant-related problems. We conclude that the mobile-bearing prosthesis
is a successful device even at long-term follow-up. 相似文献
67.
68.
血管内皮型一氧化氮合酶基因Glu298 Asp多态性与老年脑梗死的相关性研究 总被引:1,自引:0,他引:1
目的 通过病例对照研究 ,了解中国老年人群血管内皮型一氧化氮合酶 (eNOS)基因目的 通过病例对照研究 ,了解中国老年人群血管内皮型一氧化氮合酶 (eNOS)基因Glu2 98Asp多态性的分布 ,分别探讨其与老年脑梗死及血脂以及一氧化氮等脑梗死危险因素的关系。 方法对门诊及住院中确诊的 4 0例老年脑梗死和 16 9例性别、年龄相匹配的老人 ,测量他们的身高、体重及座位血压 ,并测定他们的空腹血脂、空腹血糖 (FBS)及一氧化氮 (NO)等 ,应用聚合酶链反应 (PCR)和限制性片断长度多态性 (RFLP)检测eNOS基因Glu2 98Asp多态性。结果 脑梗死和对照组eNOS基因Glu2 98Asp多态性构成有显著性差异 (χ2 =4 31,P =0 0 38) ,脑梗死组Glu/Asp基因型高于对照组(32 5 %vs 17 8% ) ;脑梗死组 2 98Asp等位基因频率高于对照组 (16 2 5 %vs 8 9% ) ,但是两组等位基因频率的分布比较 ,没有显著性差异 (χ2 =3 81,P =0 0 5 1)。结论 eNOS基因Glu2 98Asp多态性在中国老年人群中存在 ,并且基因... 相似文献
69.
70.
Feleppa Michele Di Iorio Walter Saracino Donato M. T. 《The journal of headache and pain》2004,5(2):s51-s58
We reviewed P300 and contingent negative variation (CNV) studies performed in migraine in order to identify their relevance in migraine and the role of neurophysiology in migraine. Publications available to us were completed by a Medline search. There is experimental and clinical evidence for loss of cognitive habituation in migraine which may serve as a specific diagnostic tool; therefore, we reviewed studies on migraine that analyzed habituation and lack of habituation by P300 and CNV, performing short-term habituation (STH) and long-term habituation (LTH). Finally, we described the two components of P300 (a and b) and of CNV (early and late wave) and the two abnormalities reported from the majority of studies on event-related potential in migraine: increased amplitude of average event-related potential and lack of habituation. These abnormalities are especially related to the early component characterizing orienting activity. 相似文献