全文获取类型
收费全文 | 1692583篇 |
免费 | 124276篇 |
国内免费 | 2484篇 |
专业分类
耳鼻咽喉 | 24298篇 |
儿科学 | 57963篇 |
妇产科学 | 46124篇 |
基础医学 | 250018篇 |
口腔科学 | 46136篇 |
临床医学 | 147454篇 |
内科学 | 331260篇 |
皮肤病学 | 37873篇 |
神经病学 | 129625篇 |
特种医学 | 65869篇 |
外国民族医学 | 714篇 |
外科学 | 258130篇 |
综合类 | 34223篇 |
现状与发展 | 1篇 |
一般理论 | 480篇 |
预防医学 | 128039篇 |
眼科学 | 38189篇 |
药学 | 127451篇 |
2篇 | |
中国医学 | 3241篇 |
肿瘤学 | 92253篇 |
出版年
2018年 | 16885篇 |
2016年 | 14057篇 |
2015年 | 15857篇 |
2014年 | 21994篇 |
2013年 | 33792篇 |
2012年 | 46133篇 |
2011年 | 49316篇 |
2010年 | 29337篇 |
2009年 | 27909篇 |
2008年 | 47397篇 |
2007年 | 50741篇 |
2006年 | 51310篇 |
2005年 | 49828篇 |
2004年 | 48735篇 |
2003年 | 46916篇 |
2002年 | 46276篇 |
2001年 | 82200篇 |
2000年 | 85481篇 |
1999年 | 72061篇 |
1998年 | 19405篇 |
1997年 | 17414篇 |
1996年 | 18109篇 |
1995年 | 17000篇 |
1994年 | 16091篇 |
1993年 | 14976篇 |
1992年 | 56736篇 |
1991年 | 56191篇 |
1990年 | 55089篇 |
1989年 | 52758篇 |
1988年 | 48644篇 |
1987年 | 47943篇 |
1986年 | 44731篇 |
1985年 | 42888篇 |
1984年 | 31970篇 |
1983年 | 26959篇 |
1982年 | 15431篇 |
1981年 | 14135篇 |
1980年 | 12799篇 |
1979年 | 29185篇 |
1978年 | 20526篇 |
1977年 | 17356篇 |
1976年 | 16375篇 |
1975年 | 18007篇 |
1974年 | 21207篇 |
1973年 | 20244篇 |
1972年 | 18928篇 |
1971年 | 17541篇 |
1970年 | 16450篇 |
1969年 | 15222篇 |
1968年 | 14032篇 |
排序方式: 共有10000条查询结果,搜索用时 12 毫秒
11.
12.
J. Rodríguez-Carrio A. Martínez-Zapico I. Cabezas-Rodríguez L. Benavente Á.I. Pérez-Álvarez P. López J.B. Cannata-Andía M. Naves-Díaz A. Suárez 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(2):135-143
Background and aims
Since accelerated atherosclerosis has been reported in systemic lupus erythematosus (SLE), predictive biomarkers of cardiovascular disease (CVD) are needed. Among non-traditional risk factors, bone mineral density (BMD) has been related to CVD. However, its role in SLE remains controversial. This study aims to analyze the associations of subclinical atherosclerosis with traditional and non-traditional CV risk factors.Methods and results
In a cross-sectional study, atherosclerosis burden was compared between 112 female SLE patients and 31 controls. Plaque number and carotid intima-media wall thickness (cIMT) were assessed by ultrasonography. In a retrospective study, BMD determinations obtained 5-years before the ultrasonography assessment were analyzed in a subgroup of 62 patients. Plaque frequency was increased in SLE, even in patients without CV events or carotid wall thickening. cIMT was increased in patients with CVD, positively correlated with body mass index (BMI). Interestingly, a paradoxical effect of BMI on carotid parameters was observed. Whereas underweight patients (BMI < 20) showed increased prevalence of carotid plaques with low cIMT, those with BMI > 30 showed higher cIMT and plaque burden. Overweight patients (25 < BMI<30) exhibited both elevated cIMT and plaque number. BMI was an independent predictor of BMD. In our retrospective study, patients with either clinical or subclinical CVD exhibited lower BMD levels than their CV-free counterparts. A low lumbar spine BMD independently predicted CVD development after adjusting for confounders.Conclusion
SLE was associated with a higher subclinical atherosclerosis burden, a bimodal effect being observed for BMI. Decreased BMD can be a CV risk biomarker in SLE. 相似文献13.
N. SUVAJD
I V. EMERIKI‐MARTINOVI . ARANOVI M. PETROVI M. POPOVI V. ARTIKO M. UPI I. ELEZOVI 《International journal of laboratory hematology》2006,28(5):317-320
We report the case of a littoral‐cell angioma of the spleen, a recently described benign vascular tumour, whose imaging and pathological characteristics have been discussed only by a few authors. The diagnosis was made after elective splenectomy. The CT images, scintigraphy and histological specimens are presented, and differential diagnoses discussed. 相似文献
14.
Bernard–Soulier syndrome (BSS) is a rare autosomal recessively inherited bleeding disorder. Pregnancy in patients with BSS is characterized by ante‐, intra‐, or postpartum haemorrhage, which may be delayed and severe. There is no consensus in the management of BSS in pregnancy and so far only 16 pregnancies in nine patients have been described. We report a further three pregnancies in two women with the syndrome. We also outline our management of pregnant patients with BSS. 相似文献
15.
16.
ZusammenfassungHintergrund Bedingt durch die intraoperative Katecholaminsekretion mit hämodynamischen Veränderungen, einem größeren Tumordurchmesser und einer deutlichen Neovaskularisation ist die Adrenalektomie beim Phäochromozytom im Vergleich zu anderen Nebennierenerkrankungen schwieriger und potenziell komplikationsträchtiger. Ziel unserer Studie war die Frage, ob das Risiko intraoperativer kardiovaskulärer Komplikationen durch das minimal-invasive Vorgehen potenziert wird.Patienten und Methodik Im Zeitraum zwischen Februar 1992 und Mai 2005 wurden in unserer Klinik 82 Eingriffe wegen eines Phäochromozytoms bei 71 Patienten durchgeführt. Davon wurden 8 (1) Patient(en) bi-(tri-)lateral adrenalektomiert und bei 2 Patienten erfolgte eine ipsilaterale Rezidivoperation. Eingeschlossen sind 5 weitere Patienten mit Rezidiv nach Erstoperation vor 1992. Sechsunddreißig Eingriffe erfolgten konventionell (transperitoneal n=35, retroperitoneal n=1) und 46 Operationen endoskopisch (transperitoneal n=28, retroperitoneal n=18), davon keine Konversion zum offenen Vorgehen.Ergebnisse Das mediane Alter zum Zeitpunkt der Operation betrug 45 (24–75) Jahre bei einer Anamnesedauer von 12 (0–180) Monaten. Die offen operierten Phäochromozytome waren mit 5,5 (1–19) cm vs. 3,5 (0,5–8) cm (endoskopisch) signifikant größer (p=0,0011). Patienten mit endoskopischer, insbesondere mit retroperitoneoskopischer Adrenalektomie hatten im Vergleich zum konventionellen Vorgehen intraoperativ höhere systolische und diastolische maximale Blutdruckwerte sowie Spitzen über 200 mmHg (statistisch nicht signifikant). Faktoren mit möglichem Einfluss auf intraoperative hämodynamische Veränderungen waren in der multivariaten Analyse das Geschlecht (p=0,0107), der operative Zugangsweg (p=0,0153), das Patientenalter (p=0,0364) und die Tumorgröße (p=0,0484). Die postoperative stationäre Verweildauer war nach endoskopischer Operation signifikant kürzer (p<0,0001).Schlussfolgerung Die endoskopische Adrenalektomie beim Phäochromozytom ist in der Routine ohne vermehrtes Risiko kardiovaskulärer Komplikationen die Methode der Wahl. Das offene Vorgehen sollte extraadrenalen Befunden oder sehr großen Tumoren mit Malignitätsverdacht vorbehalten bleiben. 相似文献
17.
18.
B Dederichs M Dietlein B Jenniches-Kloth M Schmidt P Theissen D Moka H Schicha 《Experimental and clinical endocrinology & diabetes》2006,114(7):366-370
BACKGROUND: Radioiodine therapy (RIT) combined with glucocorticoids is an effective therapy for Graves' disease, but it is debatable whether glucocorticoids should be applied in patients without Graves' ophthalmopathy (GO). METHODS: The effect of 0.4 - 0.5 mg prednisone every second day over a period of 5 weeks after RIT was monitored over a follow-up period of at least 12 months after RIT. A questionnaire was sent to 186 consecutive patients without GO concerning eye symptoms after RIT. 148 patients (80 %) answered. If eye symptoms had occurred after RIT, additional clinical examination was carried out at our outpatient clinic. The primary endpoint was the absence or onset of GO within the first year after RIT. RESULTS: Within 12 months after RIT the examination confirmed GO in 5 out of 148 patients (3.4 %). In all cases the symptoms were transient. No adverse reaction to the use of prednisone after RIT was noted. CONCLUSIONS: The risk of new GO in the first year after RIT was low and the clinical course of GO was mild when RIT was combined with a low-dose glucocorticoid regimen. Preventive administration of glucocorticoids can therefore be recommended in patients with Graves' disease even without evident GO. 相似文献
19.
M Vitacca M Paneroni L Bianchi E Clini A Vianello P Ceriana L Barbano B Balbi S Nava 《The European respiratory journal》2006,27(2):343-349
The present study compared four different sites and conditions for the measurement of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) in 38 spontaneous breathing tracheotomised patients. Of the patients, 28 had chronic obstructive pulmonary disease (COPD). The four different conditions were: 1) through a cuff inflated cannula (condition A); 2) through the mouth with a deflated cannula (condition B); 3) through the mouth with a phonetic uncuffed cannula (condition C); and 4) through the mouth after stoma closure (condition D). Five trials in each condition were performed using a standardised method. The measurement of both MIP and MEP differed significantly depending on the condition of measurement. MIP taken in condition A was significantly higher when compared with conditions B, C and D. MEP in condition A was significantly higher when compared with condition B and D. In condition A the highest frequency of the best measurement of MIP and MEP was observed at the fourth and fifth effort, respectively. The same results were obtained after the selection of only COPD patients. In conclusion, respiratory muscle assessment differs significantly depending on measurement condition. Measurement through inflated cannula tracheotomy yields higher values of both maximal inspiratory and maximal expiratory pressure. 相似文献
20.
A I D'hulst K R Bracke T Maes J L De Bleecker R A Pauwels G F Joos G G Brusselle 《The European respiratory journal》2006,28(1):102-112
Chronic obstructive pulmonary disease (COPD) is characterised by a local pulmonary inflammatory response to respiratory pollutants and by systemic inflammation. Tumour necrosis factor (TNF)-alpha has been implicated in systemic effects of COPD and operates by binding the p55 (R1) and p75 (R2) TNF-alpha receptors. To investigate the contribution of each TNF-alpha receptor in the pathogenesis of COPD, the present study examined the effects of chronic air or cigarette smoke (CS) exposure in TNF-alpha R1 knockout (KO) mice, TNF-alpha R2 KO mice and wild type (WT) mice. CS was found to significantly increase the protein levels of soluble TNF-alpha R1 (by four-fold) and TNF-alpha R2 (by 10-fold) in the bronchoalveolar lavage of WT mice. After 3 months, CS induced a prominent pulmonary inflammatory cell influx in WT and TNF-alpha R1 KO mice. In TNF-alpha R2 KO mice, CS-induced pulmonary inflammation was clearly attenuated. After 6 months, no emphysema was observed in CS-exposed TNF-alpha R2 KO mice in contrast to WT and TNF-alpha R1 KO mice. CS-exposed WT and TNF-alpha R1 KO mice failed to gain weight, whereas the body mass of TNF-alpha R2 KO mice was not affected. These current findings suggest that both tumour necrosis factor-alpha receptors contribute to the pathogenesis of chronic obstructive pulmonary disease, but tumour necrosis factor-alpha receptor-2 is the most active receptor in the development of inflammation, emphysema and systemic weight loss in this murine model of chronic obstructive pulmonary disease. 相似文献