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1.
Cardiac transplantation was resumed at the University Health Center of Pittsburgh in 1980 after a hiatus of 12 years. Prior to April 15, 1986, 270 hearts had been transplanted. Participants have been forced to reorder personal, professional, and institutional commitments to adapt to new demands of pre- and post-operative care and to develop flexibility in the operative scheduling of routine cardiac surgical cases. The actuarial survival has been 78, 69, and 64% at 1, 2, and 3 years. Much has been learned about evolving immunosuppression based on cyclosporine and of the allogenic response. An increasing proportion of recipients are mortally ill (54%), and for these urgent patients the wait for a donor organ continues to lengthen. The cardiac surgeon performing transplantations will need to grow with allied developments in xenotransplantation and mechanical cardiac support devices in order to keep pace with his evolving specialty.  相似文献   
2.
Interleukin-6 (IL-6) is one of the cytokines produced by human alveolar macrophages, lung parenchyma, and other cells in response to injury and infection. We hypothesized that IL-6 is released from poorly preserved lung grafts and may serve as a marker of preservation injury. Sixteen patients who received lung allografts were enrolled in this study. The average ischemic time was 284 +/- 78 minutes. Serum IL-6 level was measured before and at 4 and 24 hours after reperfusion of the grafts by an enzyme-linked immunosorbent assay. Preservation injury was assessed by (1) the need for prolonged intubation (> 7 days), (2) the arterial/alveolar oxygen tension ratio (PaO2/PAO2 ratio) at 4 hours after graft reperfusion (only in heart-lung or double lung recipients), (3) the presence of diffuse alveolar damage on first lung biopsy, and (4) the 30-day graft survival rate. IL-6 level peaked at 4 hours after reperfusion and returned to baseline at 24 hours. The patients were divided into group I (n = 6) and group II (n = 10), depending on whether the 4-hour IL-6 level was more than 1000 pg/ml or less than 500 pg/ml, respectively. Group I patients required longer intubation (p < 0.01) and had a lower PaO2/PAO2 ratio (p < 0.001), more diffuse alveolar damage (p < 0.01), and a lower graft survival rate (p < 0.01) than those of group II. No bacterial, fungal, or viral infection was found during postoperative week 1 in either group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
The interrelationships between hemodynamic variables including right ventricular (RV) performance with filling/ejection dynamics of the Novacor left ventricular assist system (LVAS) were determined in 10 of 11 patients who received LVAS as a bridge to heart transplant. Nine were successfully transplanted. Data were obtained intraoperatively, at periodic intervals up to 48 h postimplant and at explant. The hypotheses investigated included (a) RV performance influences LVAS filling characteristics and (b) LVAS pump output is influenced by systemic vascular resistance (SVR). During the period of LVAS support (2-126 days), pumping characteristics included a mean filling volume of 51 ml (range, 24-70), residual volume of 4.9 ml (range, 1-18), pump rate of 113/min (range, 63-175), and pump output of 5.81/min (range, 2.8-8.2). Multiple regression analysis identified pulmonary vascular resistance (PVR), RV stroke work index (RVSWI), and pulmonary capillary wedge pressure, but not RV ejection fraction, pulmonary artery pressure, or central venous pressure (CVP) as the most important correlates with LVAS filling volume (p less than 0.001, R2 = 0.6). In addition, LVAS pump output was influenced mainly by RVSWI, PVR, and SVR (p less than 0.001, R2 = 0.7). It was concluded that LVAS performance is highly dependent on RV function and systemic/pulmonary vascular resistances.  相似文献   
4.
Endomyocardial biopsies from heart transplant patients were cultured in vitro in the presence of Interleukin-2 and irradiated feeder cells to propagate graft-infiltrating lymphocytes. A correlation was seen between the frequency of lymphocyte growth and the degree of cellular infiltration of the biopsies. In this study, 43 of 113 (38%) histologically negative biopsies obtained from 55 patients during the first month post-transplant yielded lymphocyte cultures. The cumulative incidence of subsequent histological rejection was considerably higher in patients with such "grower" biopsies than in patients with "nongrower" biopsies. In the grower group, we were able to obtain data on alloreactivity of 32 lymphocyte cultures assayed by primed lymphocyte testing (PLT). The presence of donor-specific PLT reactivity in the cultured lymphocytes was associated with an additional risk for subsequent histological rejection. These findings suggest that the in vitro culturing of histologically negative endomyocardial biopsies will identify patients at increased risk for developing heart transplant rejection.  相似文献   
5.
Neurosurgical Review - The current literature regarding surgical treatment for tumors in the sphenopetroclival (SPC) region is merely scarce. Through a comprehensive literature review, we...  相似文献   
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To compare the pathology and histologic grading of breast cancers detected with digital breast tomosynthesis to those found with conventional digital mammography. The institutional review board approved this study. A database search for all breast cancers diagnosed from June 2012 through December 2013 was performed. Imaging records for these cancers were reviewed and patients who had screening mammography with tomosynthesis as their initial examination were selected. Five dedicated breast imaging radiologists reviewed each of these screening mammograms to determine whether the cancer was visible on conventional digital mammography or whether tomosynthesis was needed to identify the cancer. A cancer was considered mammographically occult if all five radiologists agreed that the cancer could not be seen on conventional digital mammography. The size, pathology and histologic grading for all diagnosed breast cancers were then reviewed. The Mann–Whitney U and Fisher exact tests were utilized to determine any association between imaging findings and cancer size, pathologic type and histologic grade. Sixty‐five cancers in 63 patients were identified. Ten of these cancers were considered occult on conventional digital mammography and detected with the addition of tomosynthesis. These mammographically occult cancers were significantly associated with Nottingham grade 1 histologic pathology (p = 0.02), were smaller (median size: 6 mm versus 10 mm, p = 0.07) and none demonstrated axillary nodal metastases. Breast cancers identified through the addition of tomosynthesis are associated with Nottingham grade 1 histologic pathology and prognostically more favorable than cancers identified with conventional digital mammography alone.  相似文献   
9.
Periodate-oxidized 3' ends of 5S, 23S, and 16S rRNAs from Escherichia coli were allowed to react with fluorescein thiosemicarbazide, then labeled rRNAs were reconstituted into active ribosomal subunits. The fluorescein moiety on each of the rRNAs when reconstituted into ribosomal subunits was accessible to anti-fluorescein IgG as determined by fluorescence quenching and by sucrose gradient centrifugation. The region at which an antibody molecule bond to the labeled ribosomal subunits was determined by immunoelectron microscopy. The 3' end of the 5S RNA was localized on the central protuberance of the 50S subunit. The corresponding region for the 3' end of the 23S RNA was below the stalk on the noninterfacing surface. The 3' end of the 16S RNA was localized to the upper edge of the large lobe of 30S subunits, as reported previously.  相似文献   
10.
There are several treatment options for rigid fixation at C1–C2 including Brooks and Gallie type wired fusions and C1–2 transarticular screws. The use of a Goel–Harms type fusion, a construct with C1 lateral mass screws and C2 pedicle screws, has not been extensively described in pediatric patients. Here, we describe its relatively safe and effective use for treating pediatric patients by retrospective chart review of patients treated by the senior author for atlantoaxial instability with a Goel–Harms-type constructs during a 3-year period (2005–2007). Six patients were treated using Goel–Harms-type constructs. Five patients were treated utilizing a construct containing C1 lateral mass screws and C2 pedicle screws; one patient was treated using construct containing C1 lateral mass screws and C2 trans-laminar screws. The patients ranged in age from 7 to 17 years old (mean 12.7). All patients had findings of an os odontoideum on CT scans and three of the six patients had T2 hyperintensity on MRI. Three of the six patients presented with transient neurologic deficits: quadraplegia in two patients and paresthesias in two patients. In each patient C1 lateral mass and C2 screws were placed and the subluxation was reduced to attain an anatomical alignment. No bone grafts were harvested from the iliac crest or rib. Local morsalized bone and sub-occipital skull graft was used. All patients tolerated the procedure well and were discharged home on post-operative day 3–4. The patients wore a hard cervical collar and no halo-vests were needed. All patients had solid fusion constructs and normal alignment on post-operative imaging studies performed on average 14 months post-operatively (range: 7–29). The results demonstrated that Goel–Harms fusions are a relatively safe and effective method of treating pediatric patients with atlantoaxial instability and are not dependent on vertebral anatomy or an intact ring of C1. Follow-up visits and studies in this limited series of patients demonstrated solid fusion constructs and anatomical alignment in all patients treated.  相似文献   
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