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51.
52.
Although ultra high-performance concrete (UHPC) has great performance in strength and durability, it has a disadvantage in the environmental aspect; it contains a large amount of cement that is responsible for a high amount of CO2 emissions from UHPC. Supplementary cementitious materials (SCMs), industrial by-products or naturally occurring materials can help relieve the environmental burden by reducing the amount of cement in UHPC. This paper reviews the effect of SCMs on the properties of UHPC in the aspects of material properties and environmental impacts. It was found that various kinds of SCMs have been used in UHPC in the literature and they can be classified as slag, fly ash, limestone powder, metakaolin, and others. The effects of each SCM are discussed mainly on the early age compressive strength, the late age compressive strength, the workability, and the shrinkage of UHPC. It can be concluded that various forms of SCMs were successfully applied to UHPC possessing the material requirement of UHPC such as compressive strength. Finally, the analysis on the environmental impact of the UHPC mix designs with the SCMs is provided using embodied CO2 generated during the material production. 相似文献
53.
Arizono N; Kasugai T; Yamada M; Okada M; Morimoto M; Tei H; Newlands GF; Miller HR; Kitamura Y 《Blood》1993,81(10):2572-2578
Ws/Ws rats have a small deletion at the tyrosine kinase domain of the c- kit gene and are deficient in both mucosal mast cells (MMC) and connective tissue-type mast cells (CTMC). The role of the c-kit receptor in the development of MMC and CTMC was investigated by infecting Ws/Ws and control +/+ rats with Nippostrongylus brasiliensis (NB), which induces T-cell-dependent mast cell proliferation. Although mast cells did not develop in the skin of Ws/Ws rats, a significant number of mast cells developed in the jejunum after NB infection. These mast cells had the MMC protease phenotype (rat mast cell protease [RMCP] I-/II+) and lacked heparin because they were not stained with berberine sulfate. Globule leukocytes were also detected in the mucosal epithelium of these rats. However, the number of MMC and the serum concentration of RMCP II in NB-infected Ws/Ws rats were only 13% and 7% of those of NB-infected +/+ rats, respectively. A small number of mast cells also developed in the lung, liver, and mesenteric lymph nodes of Ws/Ws rats after NB infection. Although mast cells in these tissues had the MMC phenotype throughout the observation period, the increased mast cells in the lung and liver of +/+ rats acquired a CTMC-like phenotype and were RMCP I+/II+, berberine sulfate+, and formalin resistant. These results indicate that the need for the stimulus through the c-kit receptor appears to be greater in the development of CTMC in the skin as well as for CTMC-like mast cells in the lung and liver than for the development of MMC. 相似文献
54.
Nisharahmed I. Kherada Samantha SartoriMatthew I. Tomey Marco G. MennuniOmar A. Meelu Swathi RoyBibhu D. Mohanty Usman BaberRobert Pyo Jason C. KovacicJoseph Sweeny Pedro MorenoPrakash Krishnan George D. DangasRoxana Mehran Samin K. SharmaAnnapoorna S. Kini 《International journal of cardiology》2014
Objectives
To compare the outcomes of initial one-stent (1S) versus dedicated two-stent (2S) strategies in complex bifurcation percutaneous coronary intervention (PCI) using everolimus-eluting stents (EES).Background
PCI of true bifurcation lesions is technically challenging and historically associated with reduced procedural success and increased restenosis. Prior studies comparing initial one-stent (1S) versus dedicated two-stent (2S) strategies using first-generation drug-eluting stents have shown no reduction in ischemic events and more complications with a 2S strategy.Methods
We performed a retrospective study of 319 consecutive patients undergoing PCI at a single referral center with EES for true bifurcation lesions, defined by involvement of both the main vessel (MV) and side branch (SB). Baseline, procedural characteristics, quantitative coronary angiography and clinical outcomes in-hospital and at one year were compared for patients undergoing 1S (n = 175) and 2S (n = 144) strategies.Results
Baseline characteristics were well-matched. 2S strategy was associated with greater SB acute gain (0.65 ± 0.41 mm vs. 1.11 ± 0.47 mm, p < 0.0001). In-hospital serious adverse events were similar (9% with 2S vs. 8% with 1S, p = 0.58). At one year, patients treated by 2S strategy had non-significantly lower rates of target vessel revascularization (5.8% vs. 7.4%, p = 0.31), myocardial infarction (7.8% vs. 12.2%, p = 0.31) and major adverse cardiovascular events (16.6% vs. 21.8%, p = 0.21).Conclusion
In this study of patients undergoing PCI for true coronary bifurcation lesions using EES, 2S strategy was associated with superior SB angiographic outcomes without excess complications or ischemic events at one year. 相似文献55.
Cho Soo Hyun Choe Yeong Sim Kim Hee Jin Jang Hyemin Kim Yeshin Kim Si Eun Kim Seung Joo Kim Jun Pyo Jung Young Hee Kim Byeong C. Baker Suzanne L. Lockhart Samuel N. Na Duk L. Park Seongbeom Seo Sang Won 《European journal of nuclear medicine and molecular imaging》2020,47(8):1938-1948
European Journal of Nuclear Medicine and Molecular Imaging - We developed a new method to directly calculate Centiloid (CL) units of 18F-florbetaben (FBB) and 18F-flutemetamol (FMM) without... 相似文献
56.
57.
Background We compared outcomes of surgery and radiofrequency thermal ablation (RFA) in patients with metachronous liver metastases.
Methods Between October 1995 and December 2005, 59 patients underwent hepatic resection and 30 underwent RFA for metachronous liver
metastases. Patients with extra-hepatic metastases, those who underwent both types of treatment, and those with synchronous
hepatic metastasis were excluded.
Results The two groups had similar mean age, sex ratio, comorbid medical conditions, primary disease stage, and frequency of solitary
metastases. Preoperative mean serum carcinoembryonic antigen (CEA) level was significantly higher in the RFA group (13.4 ng/mL
vs. 7.7 ng/mL; p = 0.02). Mean diameter of hepatic metastases was significantly greater in the resection than in the RFA group (3.1 cm vs.
2.0 cm; p = 0.001). Recurrence after treatment of metastasis was observed in 18 of 30 (60.0%) RFA and 33 of 59 (56%) resection patients.
Local recurrence at the RFA site was observed in 7 of 30 (23%) patients. Time to recurrence (15 vs. 8 months, p = 0.02) and overall survival (56 vs. 36 months, p = 0.005) were significantly longer in the resection than in the RFA group. In the 69 patients with solitary metastases of
diameter ≤3 cm, time to recurrence (p = 0.004) and overall survival were significantly greater in the resection group.
Conclusions Compared with hepatic resection, RFA for metachronous hepatic metastases from colorectal cancer was associated with higher
local recurrence and shorter recurrence-free and overall survival rates, even in patients with solitary, small (≤3 cm) lesions. 相似文献
58.
Nitric oxide expression in airway epithelial cells in response to tubercle bacilli stimulation 总被引:1,自引:0,他引:1
O Jung KWON Jung Hee KIM Ho Cheol KIM Gee Young SUH Jung Woong PARK Man Pyo CHUNG Hojoong KIM Chong H RHEE 《Respirology (Carlton, Vic.)》1998,3(2):119-124
Abstract In order to investigate the role of airway epithelial cells in pulmonary tuberculosis, inducible nitric oxide synthetase (iNOS) expression and nitric oxide (NO) production were studied in A549 cells. Peripheral blood mononuclear cells (PBMC) from normal volunteers were separated and cultured for 24h with LPS or tubercle bacilli (H37Rv, H37Ra). Thereafter, A549 cells were stimulated for another 24h with culture supernatant fluids of PBMC. iNOS messenger RNA (mRNA) expression was measured with Northern blot analysis and NO production was measured with the Griess reaction, which can measure nitrite concentration. iNOS mRNA expression and NO production were minimal in the control cells. iNOS mRNA expression and NO production were significantly increased with LPS ( P < 0.05) or tubercle bacilli ( P < 0.01) stimulation. However, there was no difference in iNOS mRNA expression and NO production between H37Rv and H37Ra stimulations. Interestingly, iNOS mRNA expression and NO production were greater in A549 cells stimulated with tubercle bacilli-conditioned media than in the cells stimulated with LPS-conditioned media. IL-1β, tumour necrosis factor-alpha and interferon gamma concentrations were increased in culture supernatant fluids of PBMC stimulated with tubercle bacilli. These findings suggest that airway epithelial cells may play a certain role in the pathogenesis of pulmonary tuberculosis by producing NO. However, the role of airway epithelial cells, regarding the virulence of tubercle bacilli, was not clear in this study. 相似文献
59.
Nontuberculous mycobacteria (NTM) are intracellular pathogens that elicit a specific T-cell response characterized by the
production of proinflammatory cytokines, including interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and interleukin (IL)-12.
However, little information exists regarding the levels of specific cytokines in patients with NTM lung disease. Therefore,
we compared cytokine production in peripheral blood mononuclear cells (PBMCs) from patients with NTM lung disease with that
in PBMCs from healthy controls. Pro- and anti-inflammatory cytokine production was measured by enzyme-linked immunosorbent
assay in the PBMCs of 29 patients with NTM lung disease and 15 healthy controls. Phytohemagglutinin (PHA)-induced IFN-γ production
and lipopolysaccharide (LPS)-induced production of TNF-α and IL-12p40 were significantly lower in the PBMCs of patients with
NTM lung disease than in those of the healthy controls. The production of these cytokines did not differ significantly between
patients infected with Mycobacterium avium complex (MAC) and those infected with Mycobacterium abscessus; however, IL-10 production was lower in patients infected with M. abscessus than in those infected with MAC. Decreased IFN-γ, TNF-α, and IL-12 production may be associated with host susceptibility
to the development of MAC and M. abscessus lung disease. 相似文献
60.
背景和目的:最近的研究结果表明,对其他一线药物和注射类药物(如卡那霉素、卷曲霉素)等耐药是影响耐多药结核病(MDR-TB)患者治疗效果的独立危险因素.本研究旨在明确耐其他一线药物和注射类药物对韩国不合并人免疫缺陷病毒(HIV)感染的MDR-TB患者临床疗效的影响.方法:采用回顾性队列研究分析1996年1月至2005年12月首尔国家大学附属医院治疗的211例MDR-TB患者治疗效果,排除7例丢失和7例迁出,对197例患者进行了最终分析. 相似文献