全文获取类型
收费全文 | 3161篇 |
免费 | 140篇 |
国内免费 | 28篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 48篇 |
妇产科学 | 13篇 |
基础医学 | 516篇 |
口腔科学 | 43篇 |
临床医学 | 231篇 |
内科学 | 763篇 |
皮肤病学 | 242篇 |
神经病学 | 340篇 |
特种医学 | 169篇 |
外科学 | 396篇 |
综合类 | 13篇 |
预防医学 | 113篇 |
眼科学 | 38篇 |
药学 | 166篇 |
中国医学 | 7篇 |
肿瘤学 | 224篇 |
出版年
2023年 | 7篇 |
2022年 | 13篇 |
2021年 | 44篇 |
2020年 | 28篇 |
2019年 | 35篇 |
2018年 | 35篇 |
2017年 | 41篇 |
2016年 | 43篇 |
2015年 | 74篇 |
2014年 | 88篇 |
2013年 | 136篇 |
2012年 | 180篇 |
2011年 | 170篇 |
2010年 | 112篇 |
2009年 | 123篇 |
2008年 | 235篇 |
2007年 | 233篇 |
2006年 | 236篇 |
2005年 | 204篇 |
2004年 | 204篇 |
2003年 | 220篇 |
2002年 | 185篇 |
2001年 | 51篇 |
2000年 | 40篇 |
1999年 | 45篇 |
1998年 | 52篇 |
1997年 | 41篇 |
1996年 | 29篇 |
1995年 | 38篇 |
1994年 | 15篇 |
1993年 | 25篇 |
1992年 | 15篇 |
1991年 | 25篇 |
1990年 | 16篇 |
1989年 | 15篇 |
1988年 | 15篇 |
1987年 | 17篇 |
1986年 | 23篇 |
1985年 | 13篇 |
1984年 | 7篇 |
1983年 | 13篇 |
1982年 | 17篇 |
1980年 | 8篇 |
1979年 | 15篇 |
1978年 | 11篇 |
1977年 | 8篇 |
1976年 | 8篇 |
1975年 | 7篇 |
1970年 | 10篇 |
1938年 | 6篇 |
排序方式: 共有3329条查询结果,搜索用时 31 毫秒
11.
12.
13.
Intra-operative quick insulin assay to confirm complete resection of insulinomas guided by selective arterial calcium injection (SACI) 总被引:1,自引:0,他引:1
Oliver Gimm Evelyn König Phuong Nguyen Thanh Michael Brauckhoff Wolfram Karges Henning Dralle 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(6):679-684
Background and aims Insulinomas are rare endocrine disorders. Pre-operatively, conventional imaging techniques often fail to localise the tumor.
In addition, due to the lack of quick insulin assays, intra-operative confirmation of complete resection was impossible until
recently.
Materials and methods Six patients with biochemical evidence of an insulinoma underwent pre-operative localisation studies and selective arterial
calcium injection (SACI). In addition, insulin was measured before surgery and every 10–15 min after resection of the tumor
using a quick insulin assay.
Results Pre-operative localisation studies identified the tumor correctly as follows: endosonography: three of four, magnetic resonance
imaging: two of four and SACI: six of six. Tumors in the head and body were enucleated while those in the tail were resected
(n = 2, each). Those three patients, in whom magnetic resonance imaging and/or endosonography could localise the tumors pre-operatively,
underwent laparoscopic surgery while the remaining three patients underwent open surgery. Intra-operatively, insulin dropped
to normal levels within 20 min in all cases. After a follow-up of 0.8–3 years, all patients remained biochemically cured.
Conclusions Pre-operatively, SACI appears to be a very sensitive localisation technique and may be most helpful in guiding the surgeon
if conventional imaging techniques fail to localise the tumor. Complete removal of an insulinoma can be reliably predicted
using a quick insulin assay.
This paper was presented at the 2nd Biennial Meeting of the European Society of Endocrine Surgeons (ESES), May 18–20, 2006,
Krakow, Poland. 相似文献
14.
Wolfram Grimm Jens Winzenburg Ursula Knop Jürgen Hoffmann Volker Menz Frank Grote Bernhard Maisch 《Annals of noninvasive electrocardiology》1997,2(1):20-26
Objective: This prospective study was designed to compare incidence and clinical significance of ventricular late potentials between patients with idiopathic dilated cardiomyopathy (IDC) and postinfarct patients (CAD) using exactly the same method of signal-averaged electrocardiography (SAECG) in both patient groups. Methods: Time-domain analysis of SAECG was performed in 120 consecutive patients with IDC, 120 patients with CAD, and 60 healthy controls. Ventricular late potentials were detected in 27 of 120 patients with IDC (23%) compared to 41 of 120 patients with CAD (34%; P < 0.05). Results: Ventricular late potentials were found in 2 of 60 controls (3%). During 15 ± 7 months follow-up, serious arrhythmic events occurred in 17 of 120 patients with IDC (14%) and in 13 of 120 patients with CAD (11%). The sensitivity of ventricular late potentials for future arrhythmic events was 35% for IDC compared to 77% for CAD (P < 0.05). The positive predictive value of late potentials detected by time-domain analysis was 22% for IDC versus 24% for CAD (P = ns). Conclusion: In this selected patient population with IDC and CAD, time-domain analysis of SAECG revealed a lower incidence of ventricular ate potentials in patients with IDC as compared to postinfarct patients. Whereas ventricular late potentials had a high sensitivity but a low positive predictive value for identification of postinfarct patients with serious arrhythmic events during follow-up, both sensitivity and positive predictive value of ventricular late potentials for future serious arrhythmic events were low in the setting of IDC. 相似文献
15.
Bojana Stefanovic Wolfram Schwindt Mathias Hoehn Afonso C Silva 《Journal of cerebral blood flow and metabolism》2007,27(4):741-754
The cerebrovascular coupling under neuronal nitric oxide synthase (nNOS) inhibition was investigated in alpha-chloralose anesthetized rats. Cerebral blood flow (CBF), cerebral blood volume (CBV), and blood oxygenation level dependent (BOLD) responses to electrical stimulation of the forepaw were measured before and after an intraperitoneal bolus of 7-nitroindazole (7-NI), an in vivo inhibitor of the neuronal isoform of nitric oxide synthase. Neuronal activity was measured by recording somatosensory-evoked potentials (SEPs) via intracranial electrodes. 7-Nitroindazole produced a significant attenuation of the activation-elicited CBF (P<10(-6)), CBV (P<10(-6)), and BOLD responses (P<10(-6)), without affecting the baseline perfusion level. The average DeltaCBF was nulled, while DeltaBOLD and DeltaCBV decreased to approximately 30% of their respective amplitudes before 7-NI administration. The average SEP amplitude decreased (P<10(-5)) to approximately 60% of its pretreatment value. These data describe a pharmacologically induced uncoupling between neuronal and hemodynamic responses to functional activation, and provide further support for the critical role of neuronally produced NO in the cerebrovascular coupling. 相似文献
16.
Diehl P Hantke B Hennig M Tschesche H Mittelmeier W Schmitt M Muehlenweg B 《International journal of molecular medicine》2004,13(5):711-715
Matrix metalloproteinase 13 (MMP-13), urokinase type plasminogen activator (uPA), and plasminogen activator inhibitor type-1 (PAI-1) have been reported to be involved in aseptic loosening of artificial hip joints. This study for the first time presents the protein levels of all of these factors in synovial-like interfaces between bone and prosthesis and in pseudocapsular tissues surrounding the artificial joint in patients with aseptic loosening (n=17) measured by ELISA. No differences were observed in the antigen expression of MMP-13, uPA, and PAI-1, comparing interface and pseudocapsular tissue. Also, no significant correlation between the protein expression of these factors and years from arthroplasty to revision or to type of fixation (cemented vs. cementless) was observed. As control, MMP-13, uPA, and PAI-1 antigen levels were also determined in the synovium of patients with osteoarthritis (n=10). Yet, the antigen levels of MMP-13, uPA, and PAI-1 in tissue specimens from patients with aseptic loosening of artificial hip joints were significantly higher compared to their expression in synovial capsular tissues obtained from patients with osteoarthritis. In conclusion, this study shows that elevated protein levels of uPA, PAI-1, and MMP-13 in periprosthetic pseudocapsular and interface tissues from patients after total hip replacement due to aseptic loosening seem not to be associated with the patient outcome. 相似文献
17.
Adolf Dörge Franz X. Beck Roger Rick Wolfram Nagel Klaus Thurau 《Pflügers Archiv : European journal of physiology》1990,416(3):335-338
The role of mitochondria-rich cells (MR cells) in transepithelial Na transport was investigated by determining electrolyte concentrations and Rb uptake in individual cells of frog skin epithelium using electron microprobe analysis. Measurements were performed under control conditions and after blocking the transepithelial Na transport with amiloride. Under control conditions, Na and Cl concentrations of MR cells scattered much more than those of principal cells and ranged from a few up to more than 30 mmol/kg wet weight. Rb uptake from the basal side into individual MR cells also showed a large variation and was, on the average, much less pronounced than into the principal cells. In principal cells, amiloride reduced the Na concentration and Rb accumulation. In contrast, no effect was observed upon electrolyte concentration and Rb uptake of MR cells. Rb uptake was correlated to the Na concentration of MR cells both under control conditions and after amiloride. It is concluded that, in contrast to the principal cells, MR cells are not involved in amiloride-sensitive transepithelial Na transport and that their Na/K-pump activity is very low. 相似文献
18.
Herzog BA Ott PA Dittrich MT Quast S Karulin AY Kalbacher H Karges W Tary-Lehmann M Lehmann PV Boehm BO Durinovic-Belló I 《Journal of autoimmunity》2004,23(1):45-54
Active T cell recognition of islet antigens has been postulated as the pathogenic mechanism in human type 1 diabetes, but evidence is scarce. If T cells are engaged, they are expected to display increased clonal size and exhibit a T helper (Th)1/Th2 differentiation state. We used a peptide library that covers tyrosine phosphatase IA-2, a target antigen expressed in pancreatic beta cells, to probe 8 diabetic patients and 5 HLA-matched controls. When tested in a high resolution IFNgamma/IL-4 double color ELISPOT assay directly ex vivo, the number of IA-2-reactive IFNgamma producing cells was 17-fold higher in patients than in controls and IL-4 producing cells were not present. An average of 9 peptides was recognized in the patients vs. one in the controls. Determinant recognition primarily involved CD4+ cells and showed high variability among the patients. Furthermore, anti-CD28 antibody signal enhances quantitative assessment of effector T cells in T1D patients. In vitro expansion with peptides and IL-2 results in detection of responding cells in the controls and loss of disease specificity of the T cell response. Together these data provide strong evidence for the active targeting of IA-2 by Th1 memory effector cells in human type 1 diabetes. 相似文献
19.
Depolarization-induced retrograde synaptic inhibition in the mouse cerebellar cortex is mediated by 2-arachidonoylglycerol 总被引:3,自引:0,他引:3
Bela Szabo Michal J. Urbanski Tiziana Bisogno Vincenzo Di Marzo Aitziber Mendiguren Wolfram U. Baer Ilka Freiman 《The Journal of physiology》2006,577(1):263-280
Endocannabinoids acting on CB1 cannabinoid receptors are involved in short- and long-term depression of synaptic transmission. The aim of the present study was to determine which endocannabinoid, anandamide or 2-arachidonoylglycerol (2-AG), is involved in depolarization-induced suppression of inhibition (DSI) in the cerebellar cortex, which is the most widely studied form of short-term depression. Depolarization of Purkinje cells in the mouse cerebellum led to an increase in intracellular calcium concentration and to suppression of the inhibitory input to these neurons (i.e. DSI occurred). Orlistat and RHC80267, two blockers of sn -1-diacylglycerol lipase, the enzyme catalysing 2-AG formation, abolished DSI by acting downstream of calcium influx. In contrast, DSI occurred also in the presence of a phospholipase C inhibitor. Intact operation of the calcium-dependent messengers calmodulin and Ca2+ –calmodulin-dependent protein kinase II were necessary for DSI. DSI was potentiated by an inhibitor of the main 2-AG-degrading enzyme, monoacylglycerol lipase. Interference with the anandamide metabolizing enzyme, fatty acid amide hydrolase, did not modify DSI. Thus, three kinds of observations identified 2-AG as the endocannabinoid involved in DSI in the mouse cerebellum: DSI was abolished by diacylglycerol lipase inhibitors; DSI was potentiated by a monoglyceride lipase inhibitor; and DSI was not changed by an inhibitor of fatty acid amide hydrolase. Further experiments indicated that 2-AG is the endocannabinoid mediating short-term retrograde signalling also at other synapses: orlistat abolished DSI in the rat cerebellum, DSI in the mouse substantia nigra pars reticulata and depolarization-induced suppression of excitation in the mouse cerebellum. 相似文献
20.