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961.
VDD起搏对缓慢性心律失常心力衰竭的血液动力学影响 总被引:2,自引:0,他引:2
为了评估VDD起搏对缓慢性心律失常心力衰竭的血液动力学影响,对21例心功能Ⅲ~Ⅳ级的缓慢性心律失常病人安置VDD起搏器,并用Swan-Ganz导管监测起搏前和起搏后30min、24h、48h、72h的心输出量(CO)、心脏指数(CI)、右房压(RAP)、平均肺动脉压(MPAP)和肺毛细血管楔嵌压(PCWP),并记录各时期的心房率(AR)和心室率(VR)。结果:VR在术后即时及各时期显著升高(P均<0.05),CO、CI在起搏后30min即显著升高〔分别为4.18±0.81L/minvs2.81±0.93L/min、2.36±0.66L/(minm2)vs1.18±0.63L/(minm2),P均<0.05〕,起搏48h达高峰;RAP、MPAP、PCWP在起搏后30min无显著改变(P>0.05),但24h开始显著性下降(分别为1.28±0.41kPavs1.41±0.34kPa、2.60±0.51kPavs3.40±0.56kPa、3.10±0.56kPavs3.54±0.68kPa,P均<0.05),72h后进一步降低。结果提示VDD起搏治疗能显著改善缓慢性心律失常心力衰竭的血液动力学,可作为治疗缓慢性心? 相似文献
962.
The incidence and severity of acute graft-versus-host disease (GVHD) after allogeneic transplantation using peripheral blood progenitor cells mobilized by granulocyte colony-stimulating factor (G-CSF) appear to be no worse than those after bone marrow transplantation, despite the presence of large numbers of T cells in the donor infusion. Experimental studies have shown that type-1 T cells (secreting interleukin-2 [IL-2] and interferon-gamma) mediate acute GVHD, whereas type-2 T cells (secreting IL-4 and IL-10) can prevent acute GVHD. We tested the hypothesis that G-CSF modulates T-cell function toward a type-2 response and thus reduces the severity of acute GVHD. B6 mice were injected with G-CSF or diluent for 4 days, and their splenic T cells were stimulated in vitro with alloantigen or mitogen in the absence of G-CSF. T cells from G-CSF-treated mice showed a significant increase in IL-4 production, with a simultaneous decrease in IL-2 and interferon-gamma production in response to both stimuli. We also examined the effect of G-CSF pretreatment of donors in a GVHD model (B6- ->B6D2F1). Survival was significantly improved in recipients of G-CSF- treated donors. Concanavalin-A-induced cytokine production at day 13 after transplantation also showed an increase in IL-4 along with a decrease in IL-2 and IFN-gamma production by splenocytes from recipients of G-CSF-treated bone marrow and T cells. These data show that pretreatment of donors with G-CSF polarizes donor T cells toward the production of type-2 cytokines, which is associated with reduced type-1 cytokine production and reduced severity of acute GVHD. 相似文献
963.
二尖瓣病变定位经食道超声检查与术中发现的对照研究 总被引:5,自引:1,他引:5
目的:应用经食道超声心动图序列二尖瓣病变定位切面与术中发现进行对照研究,寻找对应二尖瓣不同小叶分区的相应切面及标准化操作规程,以供临床决策及提高手术成功率。方法:二尖瓣脱垂并伴有中度以上的二尖瓣反流拟行外科手术患者53例。术前行食道超声检测瓣膜病变类型与小叶分区定位,与术中发现进行对照。二尖瓣的解剖定位采用Carpentier命名法,将前叶分为A1、A2及A3,后叶分为P1、P2及P3。术前1周及术中食道超声应用中食道四腔心切面、中食道5腔心切面、显示冠状静脉窦的短四腔心切面、两腔心切面、二尖瓣交界区两腔心切面、中食道左心室长轴切面及胃底左心室短轴切面进行二尖瓣病变的小叶分区定位。外科医生术中记录二尖瓣瓣膜脱垂、腱索断裂等病理类型及A1、A2及A3;P1、P2及P3病变部位。结果:46例资料完整的患者276个小叶被分析。在7个可以显示二尖瓣小叶分区定位的切面中,中食道五腔心切面、中食道四腔心切面、显示冠状静脉窦的短四腔切面、三腔心切面及结合彩色血流的胃底左心室短轴切面与术中发现的吻合率较高。结论:通过食道超声选择序列合理的切面可以在二尖瓣手术前进行较为准确的病变小叶分区定位,为外科手术,尤其是二尖瓣成形术提供必要的术前资料。 相似文献
964.
Jo Kamen KM Fung Hector WH Tsang Raymond CK Chung 《Geriatrics & Gerontology International》2012,12(3):372-382
We aimed to fill the literature gap by identifying the clinical benefits of aromatherapy in older adults with dementia, and its efficacy in reducing behavioral and psychological symptoms of dementia (BPSD) based on available randomized controlled trials (RCT). A systematic review of 11 clinical trials shortlisted from electronic databases from 1995 to 2011 was carried out. The RCT showed that aromatherapy had positive effects on reduction of BPSD, improvement in cognitive functions, increasing quality of life, enhancing independence of activities of daily living and so on. However, adverse effects were noted in some studies. Limitations on methodology are discussed and suggestions on directions of further studies are made. It is recommended that aromatherapy shows the potential to be applied as a therapeutic and safe complementary and alternative therapy for the management of BPSD on more evidence collected from better designed RCT. Geriatr Gerontol Int 2012; 12: 372–382. 相似文献
965.
Ajay Vallakati Yeruva Madhu Reddy Martin Emert Pramod Janga Moussa C. Mansour E. Kevin Heist Rhea Pimentel Raghuveer Dendi Donita Atkins Sudharani Bommana Srijoy Mahapatra Michael Heard Jeremy Ruskin Loren Berenbom Buddhadeb Dawn Dhanunjaya Lakkireddy 《Journal of interventional cardiac electrophysiology》2013,38(2):95-100
Background
Radiation exposure in the electrophysiology (EP) lab is a major concern to most electrophysiologists. A new technology, MediGuide? nonfluoroscopic catheter tracking system, has been used for the first time in the USA recently. We intended to evaluate the efficacy of this novel catheter tracking system in reducing radiation exposure.Methods
We performed a prospective observational study by comparing the radiation exposure with MediGuide? system to that of conventional mapping systems. The first 45 EP procedures performed with the MediGuide? system were compared to 45 matched patients undergoing similar procedures during the same time frame using conventional mapping systems (CARTO and NavX) and fluoroscopy. We collected and compared baseline characteristics, procedural variables including fluoroscopic exposure between both groups.Results
Forty-five patients underwent EP procedures using the MediGuide? technology. They were matched with an equal number of patients with conventional mapping systems. Of the 45 patients included in the study, 33 underwent right atrial flutter ablations, 5 underwent atrioventricular nodal reentrant tachycardia ablations, 4 underwent ablation of Wolf–Parkinson–White syndrome, and 3 underwent EP studies with no ablation. There were no differences in mean age, gender distribution, and body mass index between the groups. Procedure duration in the MediGuide? group was significantly lower than the duration in the conventional group (103 vs. 142 min, p?=?0.03). The fluoroscopic time was significantly less during the procedures performed with the MediGuide? technology when compared to the control group (8 vs. 21 min, p?<?0.001). No major complications occurred during the procedures in either group.Conclusion
MediGuide?, a new nonfluoroscopic catheter tracking system, is associated with more than a 50 % reduction in fluoroscopic time when compared to conventional mapping systems. 相似文献966.
In many orthopaedic operating rooms, anaesthesia providers routinely wear lead aprons for protection from radiation, but some studies have questioned whether this is needed. We conducted a systematic review to identify studies that measured the amount of radiation that anaesthetists were exposed to in the orthopaedic operating room. Multiple studies have shown that at 1.5 m from the source of radiation, anaesthetists received no radiation, or amounts so small that a person would have to be present in an unreasonable number of operations to receive cumulative doses of any significance. Radiation doses at this distance were often at the limits of the sensitivity of the measuring dosimeter. We question the need to wear lead protection for anaesthesia providers who are routinely at 1.5 m or a greater distance from standard fluoroscopy units. 相似文献
967.
T. Ptak D. Kihiczak J. N. Lawrason J. T. Rhea R. Sacknoff R. R. Godfrey R. A. Novelline 《Emergency radiology》2001,8(6):315-319
Purpose: CT scanners with helical capability are commonplace. Evaluation of multiple trauma patients using this technique is fast,
and easily performed as part of the radiological evaluation. Our purpose was to ascertain the clinical effectiveness of cervical
spine screening with helical CT in a large sample population of multitrauma patients. Materials and methods: A retrospective review was carried out using screening helical CT scans from multitrauma patients referred to the Massachusetts
General Hospital emergency department. The radiographic diagnosis was evaluated and tallied along with the clinical diagnosis
and outcome for each patient included in the study. Results: Six hundred seventy-six patients conformed to the inclusion criteria. In this series, 59 true-positive, 616 true-negative,
1 false-negative, and no false-positive findings were encountered. These data result in a sensitivity of 98.3 %, a specificity
of 100 %, and an accuracy of 99.9 %. Conclusions: Screening helical CT in the evaluation of trauma patients has a high diagnostic accuracy, and is sensitive and specific in
diagnosing clinically relevant fractures of the cervical spine. 相似文献
968.
Summary. Reticulocyte quantification in peripheral blood samples is a commonly used diagnostic indicator of erythropoietic activity. A methodology based on flow cytometry additionally separates reticulocytes into 3 groups by fluorescence staining of the residual RNA. This identifies cells as‘high (HFR), medium (MFR) and low (LFR) fluorescence intensity’reticulocytes. In Part II of the study we looked for the clinical applicability in paediatrics. Selected groups of patients with ineffective erythropoiesis, i.e. suffering from renal failure, oncologic patients with suppressed bone marrow activity caused by chemotherapy and anaemic new-born infants have been observed longitudinally for their reticulocyte maturity profiles. Data were compared to the commonly used parameters RBC, Hb and Hct. In all cases in which effective erythropoiesis returned documented by a normalization of standard blood parameters, HFR cells reacted significantly earlier than the traditional markers. These preliminary observations suggest the reticulocyte maturity pattern analysis can be used as an additional aid in diagnosis and as a helpful parameter for the monitoring of any anaemic situation. 相似文献
969.
970.
Norkasihan Ibrahim Ian CK Wong Susan Patey Stephen Tomlin Manish D Sinha Yogini Jani 《Pediatric nephrology (Berlin, Germany)》2013,28(1):25-31
Drug therapies in the management of chronic kidney disease (CKD) are complex and specialised and have a high potential for drug-related problem (DRP). In adult CKD populations, the identification and resolution of DRP has been shown to have beneficial effects on disease management, adherence and knowledge of treatment, patient??s quality of life, hospitalisation rate and length of stay and cost to the healthcare system. The focus of this article is the review of published studies on DRP in children with CKD. There is a lack of information on the epidemiology of DRP in this patient group, and research in this area is therefore needed to better understand and manage DRP in children with CKD. 相似文献