全文获取类型
收费全文 | 23292篇 |
免费 | 2251篇 |
国内免费 | 54篇 |
专业分类
耳鼻咽喉 | 313篇 |
儿科学 | 768篇 |
妇产科学 | 483篇 |
基础医学 | 3520篇 |
口腔科学 | 409篇 |
临床医学 | 3350篇 |
内科学 | 4623篇 |
皮肤病学 | 307篇 |
神经病学 | 1874篇 |
特种医学 | 563篇 |
外科学 | 2562篇 |
综合类 | 393篇 |
一般理论 | 31篇 |
预防医学 | 2858篇 |
眼科学 | 262篇 |
药学 | 1765篇 |
中国医学 | 39篇 |
肿瘤学 | 1477篇 |
出版年
2023年 | 122篇 |
2022年 | 177篇 |
2021年 | 400篇 |
2020年 | 271篇 |
2019年 | 400篇 |
2018年 | 486篇 |
2017年 | 390篇 |
2016年 | 380篇 |
2015年 | 437篇 |
2014年 | 620篇 |
2013年 | 941篇 |
2012年 | 1275篇 |
2011年 | 1443篇 |
2010年 | 776篇 |
2009年 | 661篇 |
2008年 | 1249篇 |
2007年 | 1339篇 |
2006年 | 1275篇 |
2005年 | 1257篇 |
2004年 | 1188篇 |
2003年 | 1108篇 |
2002年 | 1044篇 |
2001年 | 554篇 |
2000年 | 577篇 |
1999年 | 543篇 |
1998年 | 303篇 |
1997年 | 254篇 |
1996年 | 223篇 |
1995年 | 218篇 |
1994年 | 201篇 |
1993年 | 183篇 |
1992年 | 411篇 |
1991年 | 382篇 |
1990年 | 370篇 |
1989年 | 373篇 |
1988年 | 303篇 |
1987年 | 305篇 |
1986年 | 271篇 |
1985年 | 285篇 |
1984年 | 198篇 |
1983年 | 179篇 |
1982年 | 160篇 |
1981年 | 141篇 |
1980年 | 131篇 |
1979年 | 232篇 |
1978年 | 172篇 |
1977年 | 122篇 |
1974年 | 121篇 |
1973年 | 112篇 |
1972年 | 111篇 |
排序方式: 共有10000条查询结果,搜索用时 892 毫秒
41.
Carrier diagnosis of Duchenne muscular dystrophy using restriction fragment length polymorphisms 总被引:6,自引:0,他引:6
Molecular probes that are tightly linked to and flank the Duchenne muscular dystrophy (DMD) locus, have been used to characterize DMD mutations and diagnose female carriers. Deletions within the Xp21 region were identified for 8 of 71 families studied. Using both DNA and CK studies, accurate (96 to 98%) carrier or noncarrier diagnoses were made for 51 of 75 females at risk in 24 families with a single affected male. DNA studies resulted in an alteration of predicted risk in 40% of the cases. Recombinant diagnostic methods are useful for carrier detection in families with one or more affected males. 相似文献
42.
Although mitochondrial aldehyde dehydrogenase (ALDH2) has been thought to play a major role in acetaldehyde detoxification, and the high incidence of 'alcohol flushing' among Orientals is attributed to the inherited deficiency of ALDH2, the role of cytosolic aldehyde dehydrogenase (ALDH1) cannot be ignored. On the premise that alcohol flushing in Caucasians could be related to ALDH1 abnormalities, we examined the enzyme properties and electrophoretic mobilities of ALDH1 partially purified from red blood cells of nine unrelated alcohol flushers. One exhibited very low activity (10–20% of control level), and another exhibited moderately low activity (60%) and altered kinetic properties. The electrophoretic mobilities of these two samples were also distinguishable from the control samples. Immunological quantitation indicated that the amounts of ALDH1 protein in these two samples were not reduced in parallel with their enzyme deficiency. In the first case, the two characteristics, i.e. very low enzyme activity and alcohol flushing, were inherited by her daughter. 相似文献
43.
Neuropsychological assessment, neuroimaging, and neuropsychiatric evaluation in pediatric and adult patients with sickle cell disease (SCD)
下载免费PDF全文
![点击此处可从《Neuropsychiatric Disease and Treatment》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Christopher L Edwards Renee Dunn Raynor Miriam Feliu Camela McDougald Stephanie Johnson Donald Schmechel Mary Wood Gary G Bennett Patrick Saurona Melanie Bonner Chante Wellington Laura M DeCastro Elaine Whitworth Mary Abrams Patrick Logue Lekisha Edwards Salutario Martinez Keith E Whitfield 《Neuropsychiatric Disease and Treatment》2007,3(6):705-709
Traditionally, neuropsychological deficits due to Sickle Cell Disease (SCD) have been understudied in adults. We have begun to suspect, however, that symptomatic and asymptomatic Cerebrovascular Events (CVE) may account for an alarming number of deficits in this population. In the current brief review, we critically evaluated the pediatric and adult literatures on the neurocognitive effects of SCD. We highlighted the studies that have been published on this topic and posit that early detection of CVE via neurocognitive testing, neuropsychiatric evaluations, and neuroimaging may significantly reduce adult cognitive and functional morbidities. 相似文献
44.
45.
Susi Elaine Dal''Belo Lorena Rigo Gaspar Patrícia Maria Berardo Gonçalves Maia Campos 《Skin research and technology》2006,12(4):241-246
BACKGROUND/PURPOSE: The polysaccharide-rich composition of Aloe vera extracts (Aloe barbadensis Miller), often used in cosmetic formulations, may impart moisturizing properties to the product. The aim of this study was to evaluate the effect of cosmetic formulations containing different concentrations of freeze-dried Aloe vera extract on skin hydration, after a single and a 1- and 2-week period of application, by using skin bioengineering techniques. METHODS: Stable formulations containing 5% (w/w) of a trilaureth-4 phosphate-based blend were supplemented with 0.10%, 0.25% or 0.50% (w/w) of freeze-dried Aloe vera extract and applied to the volar forearm of 20 female subjects. Skin conditions in terms of the water content of the stratum corneum and of transepidermal water loss (TEWL) (Corneometer CM 825 and Tewameter TM 210) were analysed before and after a single and 1- and 2-week period of daily application. RESULTS: After a single application, only formulations supplemented with 0.25% and 0.50% (w/w) of Aloe vera extract increased the water content of the stratum corneum, while after the 2-week period application, all formulations containing the extract (0.10%, 0.25% and 0.50%) had the same effect, in both cases as compared with the vehicle. TEWL was not modified after a single and after 1- and 2-week period of application, when compared with the vehicle. CONCLUSION: Our results show that freeze-dried Aloe vera extract is a natural effective ingredient for improving skin hydration, possibly through a humectant mechanism. Consequently, it may be used in moisturizing cosmetic formulations and also as a complement in the treatment of dry skin. 相似文献
46.
47.
Elaine C McKevitt Eric Calvert Alex Ng Richard K Simons Andrew W Kirkpatrick Leanne Appleton D Ross G Brown 《Canadian journal of surgery》2003,46(3):211-215
INTRODUCTION: Elderly patients who suffer trauma have a higher mortality and use disproportionately more trauma resources than younger patients. To compare these 2 groups and determine the outcomes and characteristics of elderly patients, we reviewed patients in these 2 groups admitted and treated in our tertiary care provincial trauma centre. METHODS: From the provincial trauma registry we selected a cohort of 40 geriatric patients (group 1) (> or = 65 yr of age) with an ISS of 16 or more who were admitted to and spent time in our trauma service for more than 48 hours and compared them with a similar randomly selected cohort of 44 patients (group 2) aged 20-30 years. Family physicians were contacted for follow-up of these patients 2 years after discharge. We considered length of hospital stay, complications, disposition of the patients and use of consultation services. RESULTS: Patients in group 1 had a mean age of 72.1 years (range from 65-98 yr) and a mean ISS of 27.3 (range from 17-50). Patients in group 2 had a mean age of 26.3 years (range from 22-29 yr) and a mean ISS of 26.3 (range from 17-54). Hospital stay was significantly longer in the group 1: 34.5 days (95% confidence interval [CI]: 24-44 d) versus 21.6 days (95% CI: 15-28 d). More elderly patients experienced complications (35 v. 13, p < 0.001) and required medical consultations (35 v. 26, p < 0.001). In-hospital death rates were 8% (3 of 40) and 4% (2 of 44) respectively (p = 0.3). Fewer geriatric patients could be discharged home (35% [14 of 40] v. 27% [22 of 44], p = 0.056) or to rehabilitation facilities (28% [11 of 40] v. 34% [15 of 44], p = 0.3). Five geriatric patients were discharged to nursing homes (p = 0.007). Of the geriatric patients discharged to rehabilitation facilities or home, 75% were independent 2 years after discharge. CONCLUSIONS: Aggressive care for geriatric trauma patients is warranted, and resources should be directed toward rehabilitation. Based on our findings, we expect that creating a directed care pathway for these patients, targetting complications and earlier discharge, will further improve their outcomes. 相似文献
48.
Ward J M Videler Volkert B Wreesmann Freerk W van der Meulen Paul P Knegt Wytske J Fokkens 《Otolaryngology--head and neck surgery》2006,134(4):586-591
OBJECTIVES: Endoscopic sinus surgery (ESS) is considered to be the golden standard for surgery in patients with chronic rhinosinusitis and nasal polyposis. However, there is still a small group of patients unresponsive despite repetitive surgery. Radical surgery aimed at reduction of the inflammatory burden and optimization of drainage of the sinuses has been suggested as a last resort for these patients. STUDY DESIGN: A prospective, questionnaire-based study was conducted in a group of 23 patients who underwent Denker's procedure for refractory chronic rhinosinusitis. Symptoms were evaluated before Denker's procedure and 12 months and 2 years after surgery. RESULTS: Patients reported improvement of feelings of congestion in 74%, rhinorrhea in 70%, and nasal obstruction in 60% of the cases. The following postoperative improvements were statistically significant: rhinorrhea (P = 0.001), feelings of congestion (P = 0.02), and nasal obstruction (P = 0.03). Reduced olfactory perception and asthma did not improve. CONCLUSION: Radical surgery may be a viable treatment option in case of recurrent ESS failure. EBM rating: C-4. 相似文献
49.
50.
Kathleen A. Ward Sinead A. McKernan Natalina N. Durnien Wallace W. Dinsmore 《Journal of the European Academy of Dermatology and Venereology》1995,4(2):160-165
Objective Detection of HPV DNA in oral and genital lesions of a heterosexual male. 4 months after oral and vaginal intercourse with a woman with vulvar warts. Passible modes of acquisition of oral HPV infection in the male sexual partner are discussed. Setting Genitourinary Medicine clinic. Methods Polymerase chain reaction amplification of genomic DNA from oral and genital lesions. HPV DNA typing by dot blot hybridization. Results HPV DNA types 6 and 11 were identified in a polypoid tongue lesion and in a penile wart from the male sexual partner. Conclusions The acquisition of oral HPV infection in the male sexual partner may have resulted from genital-oral HPV transfer, either by direct contact with vulvar warts or by digital self-inoculation. 相似文献