全文获取类型
收费全文 | 2369篇 |
免费 | 207篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 48篇 |
妇产科学 | 40篇 |
基础医学 | 339篇 |
口腔科学 | 57篇 |
临床医学 | 289篇 |
内科学 | 380篇 |
皮肤病学 | 32篇 |
神经病学 | 292篇 |
特种医学 | 53篇 |
外科学 | 362篇 |
综合类 | 38篇 |
一般理论 | 12篇 |
预防医学 | 230篇 |
眼科学 | 100篇 |
药学 | 164篇 |
中国医学 | 1篇 |
肿瘤学 | 121篇 |
出版年
2023年 | 19篇 |
2022年 | 46篇 |
2021年 | 70篇 |
2020年 | 46篇 |
2019年 | 51篇 |
2018年 | 73篇 |
2017年 | 33篇 |
2016年 | 49篇 |
2015年 | 51篇 |
2014年 | 71篇 |
2013年 | 84篇 |
2012年 | 138篇 |
2011年 | 130篇 |
2010年 | 76篇 |
2009年 | 61篇 |
2008年 | 113篇 |
2007年 | 153篇 |
2006年 | 123篇 |
2005年 | 117篇 |
2004年 | 117篇 |
2003年 | 87篇 |
2002年 | 110篇 |
2001年 | 49篇 |
2000年 | 57篇 |
1999年 | 44篇 |
1998年 | 20篇 |
1997年 | 14篇 |
1996年 | 20篇 |
1993年 | 15篇 |
1992年 | 36篇 |
1991年 | 34篇 |
1990年 | 27篇 |
1989年 | 33篇 |
1988年 | 26篇 |
1987年 | 30篇 |
1986年 | 32篇 |
1985年 | 26篇 |
1984年 | 30篇 |
1983年 | 17篇 |
1982年 | 16篇 |
1979年 | 25篇 |
1978年 | 14篇 |
1977年 | 15篇 |
1975年 | 12篇 |
1974年 | 24篇 |
1973年 | 16篇 |
1972年 | 11篇 |
1971年 | 11篇 |
1970年 | 18篇 |
1968年 | 12篇 |
排序方式: 共有2586条查询结果,搜索用时 15 毫秒
1.
2.
Widely Metastatic Squamous Cell Carcinoma Originating from Malignant Transformation of Hypertrophic Lichen Planus in a 24‐Year‐Old Woman: Case Report and Review of the Literature
下载免费PDF全文
![点击此处可从《Pediatric dermatology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Lana X. Tong B.A. Matthew J. Weinstock M.D. Reed Drews M.D. Caroline C. Kim M.D. 《Pediatric dermatology》2015,32(3):e98-e101
Hypertrophic lichen planus (HLP) is a T‐cell‐mediated process typically presenting with hypertrophic or verrucous plaques on the lower limbs. We report the case of a 24‐year‐old woman with a history of HLP since age 3 years presenting with rapid malignant transformation of one lesion into a large squamous cell carcinoma (SCC). Subsequent examination revealed progressive, widespread metastatic involvement, and the patient ultimately died from her disease. SCC associated with HLP is rare, with a review of the literature revealing fewer than 50 cases. This case highlights the need to be aware of suspicious changes in HLP and to educate patients as to when to be reevaluated. 相似文献
3.
4.
Alex N. Bullock Julia Henckel Brian S. DeDecker Christopher M. Johnson Penka V. Nikolova Mark R. Proctor David P. Lane Alan R. Fersht 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(26):14338-14342
Some 50% of human cancers are associated with mutations in the core domain of the tumor suppressor p53. Many mutations are thought just to destabilize the protein. To assess this and the possibility of rescue, we have set up a system to analyze the stability of the core domain and its mutants. The use of differential scanning calorimetry or spectroscopy to measure its melting temperature leads to irreversible denaturation and aggregation and so is useful as only a qualitative guide to stability. There are excellent two-state denaturation curves on the addition of urea that may be analyzed quantitatively. One Zn2+ ion remains tightly bound in the holo-form of p53 throughout the denaturation curve. The stability of wild type is 6.0 kcal (1 kcal = 4.18 kJ)/mol at 25°C and 9.8 kcal/mol at 10°C. The oncogenic mutants R175H, C242S, R248Q, R249S, and R273H are destabilized by 3.0, 2.9, 1.9, 1.9, and 0.4 kcal/mol, respectively. Under certain denaturing conditions, the wild-type domain forms an aggregate that is relatively highly fluorescent at 340 nm on excitation at 280 nm. The destabilized mutants give this fluorescence under milder denaturation conditions. 相似文献
5.
To date, despite very encouraging preclinical results, almost all phase II/III clinical neuroprotection trials in traumatic
brain injury (TBI) have failed to show any consistent improvement in outcome for TBI patients. To understand the reasons behind
such developments we need to review and evaluate the evolution of trial design as a result of our changing understanding of
the pathophysiology of brain cell death and progress of translational research from the laboratory bench to the bedside. This
paper attempts to critically appraise these neuroprotection trials, rationalize the paucity of effectiveness, review any recent
developments in the field, and try to draw some conclusions on how to move forward. 相似文献
6.
L Bullock J F Fitzgerald M R Glick R B Parks J G Schnabel B G Hancock 《American journal of hospital pharmacy》1989,46(11):2321-2325
The stability of famotidine in total parenteral nutrient (TPN) solutions and the concentrations of amino acids in the presence of famotidine were determined. Two famotidine concentrations (20 mg/L and 40 mg/L) and two amino acid concentrations (20 g/L and 42.5 g/L) were studied under the following storage conditions: refrigerated for 24 hours and then kept at room temperature (20-22 degrees C) for 24 hours, at room temperature for 48 hours, or refrigerated for seven days. Control TPN solutions were studied under the same storage conditions. TPN solutions also contained dextrose 25%, electrolytes, trace elements, and vitamins. Famotidine concentration was determined at 0, 24, and 48 hours and at seven days by high-performance liquid chromatography. Amino acid concentration was determined in the TPN solutions containing 42.5 g/L of amino acids without famotidine and with famotidine 40 mg/L under both 48-hour storage conditions. At 24 hours, all solutions retained at least 95% of the initial famotidine concentration. Seven of the eight famotidine solutions retained more than 95% of the initial famotidine concentration at 48 hours. All samples refrigerated for seven days retained more than 95% of the initial famotidine concentration. The concentration of amino acids in TPN solutions containing 42.5 g/L of amino acids was not affected by the addition of famotidine 40 mg/L under either 48-hour storage condition. Famotidine in concentrations of 20 mg/L and 40 mg/L is stable under the studied 48-hour storage conditions in TPN solutions containing amino acid concentrations of either 20 g/L or 42.5 g/L.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
7.
在了解及处理坚持用药的情况较差时,医生往往遇到很多困难。困扰医生的一个主要问题是,如何护理患有急性或危及生命的疾病而不能长期坚持治疗的儿童。对医生来说,更难的是如何了解父母何时不能为子女提供适当的护理。近30%~70%的患慢性疾病者,因为治疗时间长、服用的药物种类多及症状时有缓解而不能坚持用药。临床经验表明,患有慢性疾病,如囊性纤维化、癫痫、哮喘、糖尿病患者坚持用药的情况较差。 相似文献
8.
A 57-year-old woman who had been treated with an indwelling ureteral stent for over a year was admitted with massive gross hematuria caused by a fistula between the left ureter and hypogastric artery. Despite intensive radiographic evaluation, the definitive diagnosis was made only at the time of surgical exploration. Because of radiation-induced retroperitoneal fibrosis, midureteral obstruction, and prior pelvic and abdominal surgery, primary ureteral repair was not possible, and renal autotransplantation was performed. This case illustrates the need to consider the diagnosis of ureteroarterial fistula in patients with massive hematuria who have chronic indwelling stents, and the feasibility of autotransplantation when primary ureteral repair is not feasible. 相似文献
9.
Feline hyperthyroidism bears a strong clinical and pathologic resemblance to toxic nodular goiter in humans. To evaluate whether the observed thyroid growth might be due to circulating thyroid antibodies, as has been postulated in humans, we studied the effect of purified immunoglobulin (Ig) G preparations on a rat thyroid follicular (FRTL-5) cell line. When compared with control, hyperthyroid cat IgG caused significantly increased [3H]-thymidine (Tdr) incorporation into DNA (p less than 0.02) and stimulated cellular proliferation 15-fold. Stimulation of 3H-Tdr incorporation tended to be biphasic and could be inhibited completely by a potent, specific TSH receptor blocking antibody. Hyperthyroid cat IgG also significantly inhibited 125I-bTSH binding to porcine thyroid membranes, an effect that could be reproduced using electrophoretically pure IgG and normal cat thyroid membranes. Unlike its effect on growth, hyperthyroid cat IgG did not stimulate intracellular cAMP, and there was no correlation between thyroid function in vivo and IgG growth-promoting activity in vitro. These data suggest that elevated titers of thyroid growth IgGs, probably acting through the TSH receptor, are present in feline hyperthyroidism and may play a role in goiter formation. Unlike growth, the thyroid hyperfunction observed is not IgG dependent. Further study of feline hyperthyroidism may contribute important insights into human nodular goiter and into the mediation of thyroid growth in general. 相似文献
10.