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Surgery in the prone position is often a necessity when access to posterior anatomic structures is required. However, many complications are known to be associated with this type of surgery, as physiologic changes occur with increased pressure to anterior structures. While several studies have discussed postoperative vision loss, much fewer studies with lower levels of evidence have addressed other complications. A systematic literature review was conducted using 2 different databases, and 53 papers were regarded as appropriate for inclusion. Qualitative and quantitative analysis was performed. Thirteen complications were identified. Postoperative vision loss and cardiovascular complications, including hypovolemia and cardiac arrest, had the most number of studies and highest level of evidence. Careful planning for optimal positioning, padding, timing, as well as increased vigilance are evidence-based recommendations where operative prone positioning is required.Key words: Prone, Surgery, Trunk, Supine, Retinal, Complications, Evidence based medicine, Qualitative and quantitative methodsProne positioning is a common position used for access to the posterior head, neck, and spine during spinal surgery, access to the retroperitoneum and upper urinary tracts and access to posterior structures when required during plastic surgery.1,2 Prone surgery is associated with a variety of complications many of which are derived from increased pressure on anterior structures. Rates of pressure sores as an intraoperative complication have been reported to be between 5% and 66%. As such, pressure sores incur longer hospital stays and healthcare costs.3 Postoperative vision loss can result from inappropriate orbital pressure and can also be a permanently debilitating condition. Lateral femoral cutaneous nerve neuropathy in 20% of spinal surgery cases causing pain and dysesthesia in the anterolateral thigh.4 Inappropriate pressure on vital structures of the abdomen can cause ischemia and organ failure, resulting in prolonged hospitalization, permanent disability, or death.5 Cardiovascular changes associated with prone surgery increase risk of intraoperative cardiac arrest. At the same time, prone surgery is also associated with airway management and CPR issues as access to anterior structures is limited.6 相似文献
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Structuring a safer donor-replacement program 总被引:1,自引:0,他引:1
BACKGROUND: Replacement donors are more likely than volunteer donors to have positive or abnormal tests for transfusion-transmissible disease. In an effort to increase the donor pool, workers sought to identify a safer replacement-donor subgroup that may be acceptable for routine donations. STUDY DESIGN AND METHODS: In a retrospective review and cohort study, the replacement-donor effect was separated from the new- donor effect. The relative effect the replacement donor has on the risk of transfusion-transmissible diseases, donor retention, and frequency of returning donations was then quantified by comparison against the effect of repeat volunteer donors. RESULTS: The replacement donor had 3.1 times the risk and 0.72 times the donor retention rate and made 0.81 times as many returning donations as the repeat volunteer donor. The figures for the new-donor effect were similar. The two risks were additive, making a new replacement donor particularly hazardous. If replacement donations only from repeat replacement donors were considered, the donor risk and the number of donations per returning donor were made comparable to those for the general (combined) volunteer donor. CONCLUSION: The negative effect of the replacement donor is similar in magnitude to that of the new volunteer donor. A replacement-donation program targeting repeat replacement donors has an acceptable risk profile and may be a valuable adjunct to the collection of blood from general volunteer donors. 相似文献
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D'Sa S Peggs K Pizzey A Verfuerth S Thuraisundaram D Watts M White H Hale G Waldmann H Goldstone A Mackinnon S Yong K 《British journal of haematology》2003,123(2):309-322
Summary. Immune reconstitution after conventional allogeneic transplantation is a major determinant of survival. We conducted a detailed investigation of T‐ and B‐cell immune reconstitution and clinical outcome in 19 patients with multiple myeloma undergoing reduced‐intensity stem cell transplantation using in vivo T‐cell depletion with alemtuzumab. These patients experienced delayed T‐cell recovery, particularly in the naïve (CD45 RA+) CD4 compartment. T‐cell receptor spectratype analysis showed a reduced repertoire diversity, which improved rapidly after the administration of donor leucocyte infusions and subsequent conversion to full donor T‐cell chimaerism. Post‐transplant recovery of CD19+ B cells was also delayed for up to 18 months. Spectratype analysis of IgH CDR3 repertoire revealed a gradual normalization in IgM spectratype complexity by 6–12 months after transplant. There was a high incidence of viral infection, particularly cytomegalovirus reactivation, but the regimen‐related mortality was low, perhaps because of the very low incidence of acute graft‐versus‐host disease (GVHD; grade I‐II skin GVHD was seen in 5/19 patients). Over 80% of all patients have relapsed at a median of 283 (range 153–895) d after transplant, suggesting that the initially low rate of GVHD comes at a high price with regard to the desired graft‐versus‐myeloma effect. 相似文献
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Prognostic superiority of the National Comprehensive Cancer Network International Prognostic Index over pretreatment whole‐body volumetric–metabolic FDG‐PET/CT metrics in diffuse large B‐cell lymphoma 下载免费PDF全文
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J. S. F. Zeinstra R. M. Kwee E. C. Kavanagh W. L. W. van Hemert M. E. A. P. M. Adriaensen 《Skeletal radiology》2013,42(3):447-450
In this study, we present the rare case of a patient with a multifocal giant cell tumor of the tendon sheath occurring at three different localizations along the same tendon. We review radiographic, ultrasonographic, and magnetic resonance imaging findings, and discuss previously reported cases. 相似文献
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