全文获取类型
收费全文 | 7508篇 |
免费 | 357篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 42篇 |
儿科学 | 114篇 |
妇产科学 | 149篇 |
基础医学 | 1107篇 |
口腔科学 | 227篇 |
临床医学 | 607篇 |
内科学 | 1480篇 |
皮肤病学 | 183篇 |
神经病学 | 811篇 |
特种医学 | 412篇 |
外科学 | 1054篇 |
综合类 | 71篇 |
一般理论 | 3篇 |
预防医学 | 360篇 |
眼科学 | 313篇 |
药学 | 487篇 |
中国医学 | 16篇 |
肿瘤学 | 462篇 |
出版年
2024年 | 26篇 |
2023年 | 30篇 |
2022年 | 97篇 |
2021年 | 138篇 |
2020年 | 82篇 |
2019年 | 108篇 |
2018年 | 114篇 |
2017年 | 110篇 |
2016年 | 141篇 |
2015年 | 177篇 |
2014年 | 249篇 |
2013年 | 312篇 |
2012年 | 464篇 |
2011年 | 534篇 |
2010年 | 336篇 |
2009年 | 306篇 |
2008年 | 544篇 |
2007年 | 548篇 |
2006年 | 507篇 |
2005年 | 505篇 |
2004年 | 489篇 |
2003年 | 496篇 |
2002年 | 472篇 |
2001年 | 89篇 |
2000年 | 53篇 |
1999年 | 103篇 |
1998年 | 97篇 |
1997年 | 90篇 |
1996年 | 55篇 |
1995年 | 54篇 |
1994年 | 43篇 |
1993年 | 39篇 |
1992年 | 42篇 |
1991年 | 27篇 |
1990年 | 27篇 |
1989年 | 18篇 |
1988年 | 14篇 |
1987年 | 19篇 |
1985年 | 13篇 |
1984年 | 19篇 |
1983年 | 22篇 |
1982年 | 17篇 |
1981年 | 22篇 |
1980年 | 14篇 |
1978年 | 18篇 |
1977年 | 17篇 |
1976年 | 12篇 |
1974年 | 15篇 |
1973年 | 8篇 |
1965年 | 8篇 |
排序方式: 共有7898条查询结果,搜索用时 15 毫秒
81.
Daniela Woide Veronika Mayer Thorsten Wachtmeister Norbert Hoehn Albert Zink Udo Koehler Stefan Thalhammer 《Biomedical microdevices》2009,11(3):609-614
Here we present a novel approach for horizontal transfer of single particles after laser microdissection. The developed technique is a single particle adsorbing system for highly selective and gentle horizontal transfer of microdissected fixed and living material. As mediated via low-pressure technology, the transfer process can be precisely controlled, thus facilitating horizontal particle transfer of any isolated material, e.g. tissue material, single cells or chromosomes, in addition to precise positioning for sample release. This collection method allows one to predefine target positions and enables material transfer without contamination to any planar microchip device. This contamination free transfer is indispensable for novel lab-on-a-chip systems performing nanoscale polymerase chain reaction analyses. Using virtual reaction chamber microdevices, small amounts of microdissected material—as little as one single cell—can be directly transmitted and immediately used for single cell analysis. Daniela Woide and Veronika Mayer contributed equally to this paper. 相似文献
82.
83.
84.
Kröger N Einsele H Wolff D Casper J Freund M Derigs G Wandt H Schäfer-Eckart K Wittkowsky G Schmitz N Krüger W Zabelina T Renges H Ayuk F Krüll A Zander A;German Study-group Multiple Myeloma 《Bone marrow transplantation》2003,31(11):973-979
We investigated toxicity and efficacy of in vivo T-cell depletion with anti-thymocyte globulin (ATG) as part of an intensified myeloablative conditioning regimen followed by allogeneic stem cell transplantation in patients with advanced multiple myeloma. The conditioning regimen consisted of modified total body irradiation, busulfan and cyclophosphamide (n=15) or in the case of prior dose-limiting radiotherapy of busulfan and cyclophosphamide (n=3). The median age was 44 years (range, 29-53) and the median time from diagnosis to transplant was 12 months (range, 6-144). Grade II-IV acute graft-versus-host disease (GvHD) occurred in six patients (35%). Severe grade III/IV GvHD developed in one patient (6%). Three patients died of therapy-related causes (17%). A complete remission (CR) with negative immunofixation after allogeneic transplantation was seen in eight of the evaluable patients (53%). After a median follow-up of 41 months (range, 8-84), the estimated overall survival at 6 years for all patients is 77% (CI 95%: 58-96%). The estimated progression-free survival at 6 years for all patients is 31% (CI 95%: 2-59%) and 46% (CI 95%: 9-83%) for patients with CR. In vivo T-cell depletion with ATG resulted in a low rate of severe GvHD with low treatment-related mortality, and a substantial number of long-term survivors. 相似文献
85.
Increased insulin clearance in peroxisome proliferator-activated receptor gamma2 Pro12Ala 总被引:2,自引:0,他引:2
Tschritter O Fritsche A Stefan N Haap M Thamer C Bachmann O Dahl D Maerker E Teigeler A Machicao F Häring H Stumvoll M 《Metabolism: clinical and experimental》2003,52(6):778-783
The Pro12Ala polymorphism of the peroxisome proliferator-activated receptor (PPARgamma(2)) is associated with reduced risk for type 2 diabetes. Although increased insulin sensitivity of glucose disposal and lipolysis has been reported, the exact mechanism by which the risk reduction is conferred is not clear. Because the conclusion of greater insulin sensitivity hinged upon lower insulin levels in some studies, it is possible that more efficient insulin clearance is involved. We therefore estimated insulin clearance during a euglycemic hyperinsulinemic clamp (insulin infusion rate divided by steady-state insulin concentration, 229 normal glucose tolerant [NGT] subjects), an oral glucose tolerance test (OGTT) (mean C-peptide divided by mean insulin concentrations, 406 NGT, 54 impaired glucose tolerant or mildly diabetic subjects), and a hyperglycemic clamp (120 minutes, 10 mmol/L, C-peptide divided by insulin in the steady-state, 56 NGT subjects). In the carriers of the Ala allele (prevalence approximately 24%), insulin clearance in all 3 protocols was significantly greater ( approximately 10%), than in controls. While the results from the euglycemic clamp reflect both hepatic and peripheral insulin clearance, those from the OGTT and the hyperglycemic clamp reflect mainly hepatic insulin extraction. Free fatty acids (FFA) during the steady state of the euglycemic hyperinsulinemic clamp were significantly lower in carriers of the Ala allele (26 +/- 5 micromol/L) than in controls (46 +/- 3 micromol/L, P =.02). In conclusion, the Pro12Ala polymorphism is associated with increased insulin clearance. This could be the result of reduced FFA delivery, which has been shown to improve hepatic insulin removal and sensitivity. Because PPARgamma(2) is mainly expressed in adipose tissue, one of the main regulatory effects of the polymorphism may well be the more efficient suppression of (possibly intra-abdominal) lipolysis. 相似文献
86.
Acute hepatitis C: high rate of both spontaneous and treatment-induced viral clearance 总被引:17,自引:0,他引:17
Gerlach JT Diepolder HM Zachoval R Gruener NH Jung MC Ulsenheimer A Schraut WW Schirren CA Waechtler M Backmund M Pape GR 《Gastroenterology》2003,125(1):80-88
BACKGROUND & AIMS: Acute hepatitis C virus infection accounts for approximately 20% of cases of acute hepatitis today. The aim of this study was to define the natural course of the disease and to contribute to the development of treatment strategies for acute hepatitis C virus. METHODS: The diagnosis of acute hepatitis C virus in 60 patients was based on seroconversion to anti-hepatitis C virus antibodies or clinical and biochemical criteria and on the presence of hepatitis C virus RNA in the first serum sample. RESULTS: Fifty-one of 60 (85%) patients presented with symptomatic acute hepatitis C virus. In the natural (untreated) course of acute symptomatic hepatitis C (n = 46), spontaneous clearance was observed in 24 patients (52%), usually within 12 weeks after the onset of symptoms, whereas all asymptomatic patients (n = 9) developed chronic hepatitis C. The start of antiviral therapy (interferon-alpha with or without ribavirin) beyond 3 months after the onset of acute hepatitis induced sustained viral clearance in 80% of treated patients. CONCLUSIONS: The management of acute hepatitis C has to take into account the high rate of spontaneous viral clearance within 12 weeks after the onset of symptomatic disease. Treatment of only those patients who remain hepatitis C virus RNA positive for more than 3 months after the onset of disease led to an overall viral clearance (self-limited and treatment induced) in 91% of patients, and unnecessary treatment was avoided in those with spontaneous viral clearance. Patients with asymptomatic acute hepatitis C virus infection are unlikely to clear the infection spontaneously and should be treated as early as possible. 相似文献
87.
Andreas Pfützner Itamar Raz Gabriel Bitton David Klonoff Ron Nagar Norbert Hermanns Thomas Haak 《Journal of diabetes science and technology》2015,9(1):116-122
Temperature changes on the surface of the skin lead to modifications of subcutaneous microcirculation. This phenomenon is employed in a standardized way by the InsuPad device to stabilize skin conditions before injections, which is associated with enhanced prandial insulin absorption. Three programmed warming cycles to 40°C within 50 minutes are resulting in faster insulin appearance in the plasma. Early standardized meal tolerance studies indicated a substantial improvement in postprandial glucose control when the same short-acting insulin analog dose was applied using InsuPad, and a dose reduction by 20% resulted in comparable glucose excursions. Similar results were obtained when patients applied the device under real-world conditions for 1 month. The InsuPad device was also tested in a prospective, controlled, parallel 3-month real-world study with 145 well-controlled but insulin-resistant patients with type 1 or type 2 diabetes. Patients were treated to target in both treatment arms (6.2 ± 0.5% in each group), with or without the device. However, patients with InsuPad needed 28% less prandial insulin, needed 12.5% less total insulin, and had 46% less confirmed hypoglycemic events (blood glucose < 63 mg/dL) as compared to the control group. Except for very few inflammatory or allergic skin reactions, there were no device-specific adverse events reported from these studies. In conclusion, use of InsuPad when applying prandial insulin doses may result in a safer and more efficient treatment of type 1 or type 2 diabetes. 相似文献
88.
I-Jun?LauEmail author Dean?Smith Robin?Aitchison Norbert?Blesing Pamela?Roberts Andrew?Peniket Kwee?Yong Neil?Rabin Karthik?Ramasamy 《Annals of hematology》2015,94(4):643-649
Treatment options are limited in myeloma relapsed or refractory to both bortezomib and lenalidomide (double-relapsed/refractory multiple myeloma; DRMM). Bendamustine is an antitumour agent that has efficacy in relapsed myeloma. We retrospectively analysed data from 30 DRMM patients who received a combination of bendamustine, thalidomide and dexamethasone (BTD) in 28-day treatment cycles. Bendamustine was administered with a cumulative dose of up to 200 mg/m2. Thalidomide (50–150 mg) was given daily as tolerated, and dexamethasone was given at an equivalent dose of up to 160 mg per cycle. A median of 5 (2–9) treatment cycles were administered per patient. Twenty-six patients (87 %) achieved stable disease or better. At a median follow-up time of 12.1 (2.3–21.5) months, median (95 % CI) progression-free survival and overall survival were 4.0 (2.6–5.3) months and 7.2 (5.2–9.2) months, respectively. The most common grade 3–4 adverse events were haematological: anaemia (n?=?8, 34.8 %), neutropenia (n?=?16, 69.6 %) and thrombocytopenia (n?=?10, 43.5 %). Non-haematological toxicities included pain (n?=?3, 13.0 %), infection (n?=?7, 30.4 %) and sensory neuropathy (n?=?1, 4.3 %). We propose that BTD is a viable salvage treatment option for DRMM patients. 相似文献
89.
Jill?Vanmassenhove Norbert?Lameire Annemieke?Dhondt Raymond?Vanholder Wim?Van BiesenEmail author 《BMC nephrology》2015,16(1):112
Background
It is unclear how modifications in the way to calculate serum creatinine (sCr) increase and in the cut-off value applied, influences the prognostic value of Acute Kidney Injury (AKI). We wanted to evaluate whether these modifications alter the prognostic value of AKI for prediction of mortality at 3 months, 1 and 2 years.Methods
We prospectively included 195 septic patients and evaluated the prognostic value of AKI by using three different algorithms to calculate sCr increase: either as the difference between the highest value in the first 24 h after ICU admission and a pre-admission historical (ΔHIS) or an estimated (ΔEST) baseline value, or by subtracting the ICU admission value from the sCr value 24 h after ICU admission (ΔADM). Different cut-off levels of sCr increase (0.1, 0.2, 0.3, 0.4 and 0.5 mg/dl) were evaluated.Results
Mortality at 3 months, 1 and 2 years in AKI defined as ΔADM?>?0.3 mg/dl was 48.1 %, 63.0 % and 63.0 % vs 27.7 %, 39.8 % and 47.6 % in no AKI respectively (OR(95%CI): 2.42(1.06-5.54), 2.58(1.11-5.97) and 1.87(0.81-4.33); 0.3 mg/dl was the lowest cut-off value that was discriminatory. When AKI was defined as ΔHIS?>?0.3 mg/dl or ΔEST?>?0.3 mg/dl, there was no significant difference in mortality between AKI and no AKI.Conclusions
The prognostic value of a 0.3 mg/dl increase in sCr, on mortality in sepsis, depends on how this sCr increase is calculated. Only if the evolution of serum creatinine over the first 24 h after ICU admission is taken into account, an association with mortality is found.90.
Direct detection and differentiation of Legionella spp. and Legionella pneumophila in clinical specimens by dual-color real-time PCR and melting curve analysis
下载免费PDF全文

Reischl U Linde HJ Lehn N Landt O Barratt K Wellinghausen N 《Journal of clinical microbiology》2002,40(10):3814-3817
A dual-color LightCycler PCR assay targeting the 16S rDNA gene of Legionella spp. was established. By using two pairs of hybridization probes, Legionella spp. and Legionella pneumophila could be detected and differentiated simultaneously. With 26 culture-positive and 42 culture-negative respiratory specimens from patients with atypical pneumonia, 100% sensitivity and specificity was observed for L. pneumophila. 相似文献