全文获取类型
收费全文 | 1049篇 |
免费 | 58篇 |
国内免费 | 11篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 115篇 |
妇产科学 | 11篇 |
基础医学 | 84篇 |
口腔科学 | 36篇 |
临床医学 | 169篇 |
内科学 | 239篇 |
皮肤病学 | 15篇 |
神经病学 | 22篇 |
特种医学 | 214篇 |
外科学 | 67篇 |
综合类 | 35篇 |
预防医学 | 42篇 |
眼科学 | 7篇 |
药学 | 30篇 |
1篇 | |
肿瘤学 | 30篇 |
出版年
2021年 | 3篇 |
2020年 | 7篇 |
2019年 | 7篇 |
2018年 | 11篇 |
2017年 | 11篇 |
2016年 | 8篇 |
2015年 | 20篇 |
2014年 | 19篇 |
2013年 | 18篇 |
2012年 | 18篇 |
2011年 | 16篇 |
2010年 | 38篇 |
2009年 | 45篇 |
2008年 | 24篇 |
2007年 | 9篇 |
2006年 | 14篇 |
2005年 | 15篇 |
2004年 | 13篇 |
2003年 | 13篇 |
2002年 | 21篇 |
2001年 | 16篇 |
2000年 | 11篇 |
1999年 | 19篇 |
1998年 | 83篇 |
1997年 | 84篇 |
1996年 | 89篇 |
1995年 | 58篇 |
1994年 | 52篇 |
1993年 | 45篇 |
1992年 | 20篇 |
1991年 | 21篇 |
1990年 | 11篇 |
1989年 | 36篇 |
1988年 | 30篇 |
1987年 | 37篇 |
1986年 | 18篇 |
1985年 | 30篇 |
1984年 | 21篇 |
1983年 | 19篇 |
1982年 | 16篇 |
1981年 | 17篇 |
1980年 | 9篇 |
1979年 | 4篇 |
1978年 | 6篇 |
1977年 | 8篇 |
1976年 | 9篇 |
1975年 | 8篇 |
1971年 | 2篇 |
1969年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有1118条查询结果,搜索用时 0 毫秒
71.
WY Khoder AJ Becker B Schlenker S Tritschler PJ Bastian CG Stief 《European journal of medical research》2009,14(7):320-322
Introduction
Rectal polypectomy causes thinning (or even perforation) of the rectal wall in addition to thermic injury at the polypectomy site.Case report
We present a rare case of spontaneous rectal perforation after uncomplicated nerve sparing endoscopic extraperitoneal radical prostatectomy in a patient with a previous history of rectal polypectomy at the perforation site. The patient could be treated conservatively. There was complete healing of the fistula without any effect on functional results. This Conservative therapy for such rectal perforations is indicated if the patient''s general condition remains stable without any signs of infection.Conclusions
Polypectomy is an important risk factor for rectal perforation during nsEERPE. Adequate time interval should be given to allow healing and avoid adding further thermal wall damage which may obscure healing leading to complications like fistula. Conservative therapy for small missed rectal perforations constitutes an attractive, feasible and non invasive treatment entity. Following this principle we have not faced this complication in following similar cases. 相似文献72.
PJ Nelemans NWJ Kelleners‐Smeets 《Journal of the European Academy of Dermatology and Venereology》2011,25(5):565-569
Background As a result of the high prevalence, basal cell carcinoma (BCC) causes a significant and expensive health care problem. Objective In this study, we evaluate the proportional increase in BCC by histological subtype over the last two decades. Methods We retrospectively reviewed all primary histological confirmed BCCs diagnosed in the Maastricht University Medical Centre in The Netherlands in the years 1991, 1999 and 2007. Results An annual increase of the number of BCCs of 7% for both genders was shown. The age‐standardized incidence rates for BCC increased between 1991 and 2007 from 54.2 to 162.1 per 100 000 men and from 61.7 to 189.8 per 100 000 women. The proportion of superficial BCC increased significantly from 17.6% to 30.7%. Conclusion The incidence of BCC is continuing to increase this century. The observed shift to the superficial histological subtype, which can be treated non‐surgically, might reduce the workload in the busy dermatologists practice. 相似文献
73.
H Kaube YE Knight RJ Storer KL Hoskin A May PJ Goadsby 《Cephalalgia : an international journal of headache》1999,19(6):592-597
It remains an open question as to whether cortical spreading depression (CSD) is the pathophysiological correlate of the neurological symptoms in migraine with aura. In the experimental animal, CSD is an electrophysiological phenomenon mainly mediated via NMDA receptors. However, according to case reports in humans, visual aura in migraine can be alleviated by vasodilator substances, such as amyl nitrite and isoprenaline. There is also circumstantial evidence that brainstem nuclei (dorsal raphe nucleus and locus coeruleus) may play a pivotal role in the initiation of aura. In this study, CSD was elicited in alpha-chloralose anesthetized cats by cortical needle stab injury and monitored by means of laser Doppler flowmetry. Topical application of isoprenaline (0.1-1%) and amyl nitrite (0.05%) onto the exposed cortex had no effect on the elicitation or propagation of CSD. Also, after supracollicular transection, subsequent CSDs showed no differences in the speed of propagation and associated flow changes. We conclude from these data that--given CSD probably exists in humans during migraine--spreading neurological deficits during migraine aura are independent of brainstem influence and have a primarily neuronal rather than vascular mechanism of generation. 相似文献
74.
75.
76.
77.
Hans Bosma Martin PJ van Boxtel Gertrudis IJM Kempen Jacques ThM van Eijk Jelle Jolles 《BMC public health》2007,7(1):179
Background
The aims of this study were to examine the extent to which higher intellectual abilities protect higher socio-economic groups from functional decline and to examine whether the contribution of intellectual abilities is independent of childhood deprivation and low birth weight and other socio-economic and developmental factors in early life. 相似文献78.
M. Trent Herdman Natthida Sriboonvorakul Stije J. Leopold Sam Douthwaite Sanjib Mohanty M. Mahtab Uddin Hassan Richard J. Maude Hugh WF Kingston Katherine Plewes Prakaykaew Charunwatthana Kamolrat Silamut Charles J. Woodrow Kesinee Chotinavich Md. Amir Hossain M. Abul Faiz Saroj Mishra Natchanun Leepipatpiboon Nicholas J. White Nicholas PJ Day Joel Tarning Arjen M. Dondorp 《Critical care (London, England)》2015,19(1)
IntroductionSevere falciparum malaria is commonly complicated by metabolic acidosis. Together with lactic acid (LA), other previously unmeasured acids have been implicated in the pathogenesis of falciparum malaria.MethodsIn this prospective study, we characterised organic acids in adults with severe falciparum malaria in India and Bangladesh. Liquid chromatography-mass spectrometry was used to measure organic acids in plasma and urine. Patients were followed until recovery or death.ResultsPatients with severe malaria (n=138), uncomplicated malaria (n=102), sepsis (n=32) and febrile encephalopathy (n=35) were included. Strong ion gap (mean±SD) was elevated in severe malaria (8.2 mEq/L±4.5) and severe sepsis (8.6 mEq/L±7.7) compared with uncomplicated malaria (6.0 mEq/L±5.1) and encephalopathy (6.6 mEq/L±4.7). Compared with uncomplicated malaria, severe malaria was characterised by elevated plasma LA, hydroxyphenyllactic acid (HPLA), α-hydroxybutyric acid and β-hydroxybutyric acid (all P<0.05). In urine, concentrations of methylmalonic, ethylmalonic and α-ketoglutaric acids were also elevated. Multivariate logistic regression showed that plasma HPLA was a strong independent predictor of death (odds ratio [OR] 3.5, 95 % confidence interval [CI] 1.6–7.5, P=0.001), comparable to LA (OR 3.5, 95 % CI 1.5–7.8, P=0.003) (combined area under the receiver operating characteristic curve 0.81).ConclusionsNewly identified acids, in addition to LA, are elevated in patients with severe malaria and are highly predictive of fatal outcome. Further characterisation of their sources and metabolic pathways is now needed.
Electronic supplementary material
The online version of this article (doi:10.1186/s13054-015-1023-5) contains supplementary material, which is available to authorized users. 相似文献79.
Genetic factors affecting the consistency and magnitude of changes in plasma cholesterol in response to dietary challenge 总被引:3,自引:0,他引:3
Humphries SE; Talmud PJ; Cox C; Sutherland W; Mann J 《QJM : monthly journal of the Association of Physicians》1996,89(9):671-680
We examined the role of common genetic variation in determining the
consistency and magnitude of change in plasma total cholesterol (TC) levels
in response to two separate changes from a high-saturated (SFA) to a
low-saturated/high-polyunsaturated-fat (PUFA) diet, in a group of
free-living healthy men and women. Consistent responders were defined as
those whose mean difference in the change in TC was within one SD of the
mean for all participants, and the remainder were defined as variable
responders. DNA was obtained from 55 individuals and genotype determined at
the apolipoprotein (apo) B locus (signal peptide, SP), apoCIII (C1100-T)
and lipoprotein lipase (LPL) gene loci (HindIII). In the 38 consistent
responders, the apoBSP24 allele was significantly more common than in the
17 individuals with a variable response (0.29 vs. 0.12; p < 0.05). No
other polymorphism showed a significant frequency difference between
groups. In the group as a whole, the correlation between the change in TC
level in response to the first and second dietary change was 0.28 (p =
0.05), but those with one or more apoB SP24 alleles and those with the
apoCIII genotype CC had a significantly higher correlation than those with
other genotypes (0.46 (p = 0.05) vs. 0.12 (NS) and 0.31 (p = 0.05) vs. 0.02
(NS), respectively). In the group as a whole, mean response left TC 10%
higher on the SFA than on the PUFA diet, and neither apoB nor apoCIII
genotypes affected the magnitude of this response. However, individuals
with the LPL HindIII genotype H+ H+ had a significantly smaller change in
mean TC in response to diet than those with one or more H- allele (9.3% vs.
14.4%; p = 0.03). Thus variation at the apoB and apoCIII loci affects the
consistency of response to change in dietary fat content, while variation
at the LPL gene locus affects magnitude of response.
相似文献
80.
Neuropeptides in migraine and cluster headache 总被引:5,自引:0,他引:5
The cerebral circulation is invested by a rich network of neuropeptide Y (NPY) and noradrenaline containing sympathetic nerve fibers in arteries, arterioles and veins. However, the nerve supply of vasoactive intestinal peptide (VIP), substance P (SP) and calcitonin gene-related peptide (CGRP) containing fibers is sparse. While noradrenaline and NPY cause vasoconstriction, VIP, SP and CGRP are potent vasodilators. Stimulation of the trigeminal ganglion in cat and man elicits release of SP and CGRP. Subjects with spontaneous attacks of migraine show release of CGRP in parallel with headache. Cluster headache patients have release of CGRP and VIP during bouts. Treatment with sumatriptan aborts headache in migraine and cluster headache as well as the concomitant peptide release. 相似文献