全文获取类型
收费全文 | 25591篇 |
免费 | 1953篇 |
国内免费 | 444篇 |
专业分类
耳鼻咽喉 | 189篇 |
儿科学 | 733篇 |
妇产科学 | 691篇 |
基础医学 | 3121篇 |
口腔科学 | 477篇 |
临床医学 | 3272篇 |
内科学 | 4347篇 |
皮肤病学 | 615篇 |
神经病学 | 2330篇 |
特种医学 | 760篇 |
外国民族医学 | 11篇 |
外科学 | 2611篇 |
综合类 | 1465篇 |
现状与发展 | 2篇 |
一般理论 | 17篇 |
预防医学 | 2662篇 |
眼科学 | 645篇 |
药学 | 1886篇 |
8篇 | |
中国医学 | 405篇 |
肿瘤学 | 1741篇 |
出版年
2024年 | 39篇 |
2023年 | 236篇 |
2022年 | 501篇 |
2021年 | 835篇 |
2020年 | 590篇 |
2019年 | 714篇 |
2018年 | 779篇 |
2017年 | 596篇 |
2016年 | 680篇 |
2015年 | 856篇 |
2014年 | 1069篇 |
2013年 | 1389篇 |
2012年 | 1993篇 |
2011年 | 1970篇 |
2010年 | 1274篇 |
2009年 | 993篇 |
2008年 | 1632篇 |
2007年 | 1709篇 |
2006年 | 1637篇 |
2005年 | 1506篇 |
2004年 | 1365篇 |
2003年 | 1295篇 |
2002年 | 1188篇 |
2001年 | 343篇 |
2000年 | 302篇 |
1999年 | 282篇 |
1998年 | 235篇 |
1997年 | 218篇 |
1996年 | 198篇 |
1995年 | 170篇 |
1994年 | 119篇 |
1993年 | 131篇 |
1992年 | 135篇 |
1991年 | 103篇 |
1990年 | 105篇 |
1989年 | 83篇 |
1988年 | 78篇 |
1987年 | 53篇 |
1986年 | 60篇 |
1985年 | 59篇 |
1984年 | 63篇 |
1983年 | 47篇 |
1982年 | 61篇 |
1981年 | 51篇 |
1980年 | 40篇 |
1979年 | 23篇 |
1978年 | 27篇 |
1977年 | 18篇 |
1975年 | 18篇 |
1974年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Norwani Basir Pemasari Upali Telisinghe Vui Heng Chong 《The Indian journal of surgery》2015,77(6):545-546
Paraneoplastic pemphigus is a relatively rare but significant acquired autoimmune mucocutaneous disorder that is characterised by diffuse erythema, painful blistering and sores of the skin and mucus membranes. The underlying pathogenesis is believed to be triggered by altered immune system in response to underlying neoplasm. The manifestations can predate, occur at the same time or after the diagnosis of cancer. Associations with gastric cancer have only been reported twice. A 78-year-old lady presented with a month’s history of extensive skin lesions that started off as bullous lesions and biopsy revealed bullous pemphigus. Endoscopy for anemia revealed gastric cancer. This case reinforced the need to consider underlying malignancy in elderly patient with new onset dermatological presentation. 相似文献
2.
3.
Erin L. Sutfin Jennifer Cornacchione Ross Allison J. Lazard Elizabeth Orlan Cynthia K. Suerken Kimberly D. Wiseman 《Health communication》2019,34(3):343-351
ABSTRACTAdolescents and young adults smoke waterpipe tobacco (WT) and cigarillos, at least in part, based on erroneous beliefs that these products are safer than cigarettes. To address this challenge, we used a systematic, three-phase process to develop a health communication campaign to discourage WT and cigarillo smoking among at-risk (tobacco users and susceptible non-users) 16- to 25-year-olds. In Phase 1, we used a national phone survey (N = 896) to determine salient message beliefs. Participants reported constituents (i.e., harmful chemicals) emitted by the products were worrisome. In Phase 2, we developed and evaluated four message executions, with varying imagery, tone, and unappealing products with the same constituents, using focus groups (N = 38). Participants rated one execution highly, resulting in our development of a campaign where each message: (1) identified a tobacco product and constituent in the smoke; (2) included an image of an unappealing product containing the constituent (e.g., pesticides, gasoline) to grab attention; and (3) used a humorous sarcastic tone. In Phase 3, we tested the campaign messages (17 intervention and six control) with a nationally representative online survey (N = 1,636). Participants rated intervention and control messages highly with few differences between them. Exposure to messages resulted in significant increases in all risk beliefs from pre to post (p < 0.05). For WT, intervention messages increased beliefs about addiction more than control messages (p < 0.05). This systematic, iterative approach resulted in messages that show promise for discouraging WT and cigarillo use. 相似文献
4.
Emmi Helle Aldo Córdova-Palomera Tiina Ojala Priyanka Saha Praneetha Potiny Stefan Gustafsson Erik Ingelsson Michael Bamshad Deborah Nickerson Jessica X. Chong University of Washington Center for Mendelian Genomics Euan Ashley James R. Priest 《Genetic epidemiology》2019,43(2):215-226
Loss of function variants in NOTCH1 cause left ventricular outflow tract obstructive defects (LVOTO). However, the risk conferred by rare and noncoding variants in NOTCH1 for LVOTO remains largely uncharacterized. In a cohort of 49 families affected by hypoplastic left heart syndrome, a severe form of LVOTO, we discovered predicted loss of function NOTCH1 variants in 6% of individuals. Rare or low-frequency missense variants were found in 16% of families. To make a quantitative estimate of the genetic risk posed by variants in NOTCH1 for LVOTO, we studied associations of 400 coding and noncoding variants in NOTCH1 in 1,085 cases and 332,788 controls from the UK Biobank. Two rare intronic variants in strong linkage disequilibrium displayed significant association with risk for LVOTO amongst European-ancestry individuals. This result was replicated in an independent analysis of 210 cases and 68,762 controls of non-European and mixed ancestry. In conclusion, carrying rare predicted loss of function variants in NOTCH1 confer significant risk for LVOTO. In addition, the two intronic variants seem to be associated with an increased risk for these defects. Our approach demonstrates the utility of population-based data sets in quantifying the specific risk of individual variants for disease-related phenotypes. 相似文献
5.
6.
Neetu Radhakrishnan M.D. Chong. H. Park M.D. Barry M. Kaplan M.D. F.A.C.C. Rajiv Jauhar M.D. F.A.C.C. 《The International journal of angiology》2006,15(1):37-42
A 65-year-old man developed acute limb ischemia, severe abdominal wall and lower limb livedo reticularis following a coronary
angiogram. The differential diagnoses of acute limb ischemia and multiple cholesterol emboli syndrome (MCES) are discussed.
This work was performed at Long Island Jewish Medical Center, 270-05, 76th Avenue, New Hyde Park, NY 11040. 相似文献
7.
ATM-dependent DNA damage surveillance in T-cell development and leukemogenesis: the DSB connection 总被引:1,自引:0,他引:1
Summary: The immune system is capable of recognizing and eliminating an enormous array of pathogens due to the extremely diverse antigen receptor repertoire of T and B lymphocytes. However, the development of lymphocytes bearing receptors with unique specificities requires the generation of programmed double strand breaks (DSBs) coupled with bursts of proliferation, rendering lymphocytes susceptible to mutations contributing to oncogenic transformation. Consequently, mechanisms responsible for monitoring global genomic integrity must be activated during lymphocyte development to limit the oncogenic potential of antigen receptor locus recombination. Mutations in ATM (ataxia-telangiectasia mutated), a kinase that coordinates DSB monitoring and the response to DNA damage, result in impaired T-cell development and predispose to T-cell leukemia. Here, we review recent evidence providing insight into the mechanisms by which ATM promotes normal lymphocyte development and protects from neoplastic transformation. 相似文献
8.
Steve Vucic Kevin D Cairns Kristin R Black Peter Siao Tick Chong Didier Cros 《Clinical neurophysiology》2006,117(2):392-397
OBJECTIVE: Cervical nerve root stimulation (CRS) is a technique of assessing the proximal segments of motor axons destined to upper extremity muscles. Few studies report normal values. The objective was to determine CMAP onset-latencies and CMAP amplitude, area, and duration changes in healthy controls for the abductor pollicis brevis (APB), abductor digiti minimi (ADM), biceps, and riceps muscles. In addition, to determine the tolerability of CRS, as measured by the visual analog scale (VAS). METHODS: We studied 21 healthy volunteers prospectively with CRS using four target muscles (APB, ADM, biceps, and triceps) bilaterally. Collision studies were used in all APB recordings. VAS was obtained in all subjects. RESULTS: Mean CMAP onset-latencies were: APB 14 +/- 1.5 ms; ADM 14.2 +/- 1.5 ms; biceps 5.4 +/- 0.6 ms; triceps 5.4 +/- 1.0 ms. Onset-latency significantly correlated with height for all nerves. The mean change in CMAP amplitude and area (%) between most distal stimulation and CRS was: APB reduction of 15.1 +/- 11.6 and 4.9 +/- 3.6%; ADM reduction of 21.1 +/- 10.7 and 17.2 +/- 8.8; biceps reduction of 10 +/- 11.5 and reduction of 8.7 +/- 6.8; triceps increase of 3.3 +/- 5.2 and 11.0 +/- 9.9% respectively. Mean CMAP duration change between most distal stimulation and CRS was: APB, increase of 20.4 +/- 7.4%; ADM, increase of 14.4 +/- 8.5%; biceps, increase of 13.9 +/- 10.8%; triceps, increase of 7.7 +/- 6.7%. The mean VAS score was 3.8 +/- 1.2, and all subjects completed the study. CONCLUSIONS: The present study establishes normative data and indicates that CRS is a well-tolerated technique. SIGNIFICANCE: The normal values may be used as reference data for the needle CRS technique in the assessment of proximal conduction abnormalities. 相似文献
9.
10.
Sonographic features of benign thyroid nodules: interobserver reliability and overlap with malignancy. 总被引:4,自引:0,他引:4
Jeffrey R Wienke Wui K Chong Julia R Fielding Kelly H Zou Carol A Mittelstaedt 《Journal of ultrasound in medicine》2003,22(10):1027-1031
OBJECTIVE: To prospectively determine the sonographic findings of nodular hyperplasia of the thyroid, to compare these with reported findings associated with malignancy, and to assess interobserver reliability. METHODS: Seventy thyroid nodules were scanned, and then biopsies of the nodules were performed under sonographic guidance with fine-needle cytologic analysis; in all cases images were reviewed by 2 experienced radiologists without knowledge of clinical outcome. Findings reported associated with malignancy were specifically assessed. Interobserver agreement between the expert and secondary readers for each finding was calculated by the kappa or weighted kappa statistic and the Fisher exact test of independence. RESULTS: There were 68 benign and 2 malignant nodules in a population of 63 female and 7 male patients. The mean benign nodule size was 2.9 cm; 60% were solid; 54% were hypoechoic; 59% were microlobulated or macrolobulated; 47% had central vascularity; 24% contained calcifications; and 82% were elliptical in shape. There was very good interobserver reliability for the presence of calcium (kappa = 0.91) and good agreement for the presence and location of vascularity (kappa = 0.75) and the amount of cystic components (kappa = 0.62; all P < .01). CONCLUSIONS: Sixty-nine percent of benign nodules had at least 1 finding reported previously as associated with malignancy. The interobserver reliability of the sonographic findings was good to very good for 3 of the 5 findings assessed. 相似文献