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1.
Background: Neuraxial blockade is used as primary anesthetic technique in one third of surgical procedures. The authors tested whether bisoprolol would protect patients at risk for cardiovascular complications undergoing surgery with spinal block.

Methods: The authors performed a double-blinded, placebo-controlled, multicenter trial to compare the effect of bisoprolol with that of placebo on 1-yr composite outcome including cardiovascular mortality, nonfatal myocardial infarction, unstable angina, congestive heart failure, and cerebrovascular insult. Bisoprolol was given orally before and after surgery for a maximum of 10 days. Adrenergic receptor polymorphisms and safety outcome measures of bisoprolol therapy were also determined.

Results: A total of 224 patients were enrolled. Spinal block could not be established in 5 patients. One hundred ten patients were assigned to the bisoprolol group, and 109 patients were assigned to the placebo group. The mean duration of treatment was 4.9 days in the bisoprolol group and 5.1 days in the placebo group. Bisoprolol therapy reduced mean heart rate by 10 beats/min. The primary outcome was identical between treatment groups and occurred in 25 patients (22.7%) in the bisoprolol group and 24 patients (22.0%) in the placebo group during the 1-yr follow-up (hazard ratio, 0.97; 95% confidence interval, 0.55-1.69; P = 0.90). However, carriers of at least one Gly allele of the [beta]1-adrenergic receptor polymorphism Arg389Gly showed a higher number of adverse events than Arg homozygous (32.4% vs. 18.7%; hazard ratio, 1.87; 95% confidence interval, 1.04-3.35; P = 0.04).  相似文献   

2.
To evaluate the reliability of Doppler ultrasonography (US) in identifying children with renal artery stenosis (RAS) among those with hypertension, we compared Doppler US results in 22 hypertensive children (mean age 8.9±4.3 years), with (13 cases) and without RAS at angiography, and in 33 normotensive children (mean age 8.8±4.7 years). We observed 2 false-negatives and 2 false-positives with Doppler US. Of the 2 false-negative diagnoses, 1 had RAS on an accessory renal artery located behind a normal upper polar artery and the other was observed in a patient with bilateral multiple stenosis of the very distal segments of renal arteries. The 2 false-positive diagnoses were due to sinuous left renal artery and to technical reasons, respectively. In another patient, Doppler US showed a tight RAS, while arteriography was normal. RAS was subsequently confirmed by a second arteriography. Peak systolic velocity values of Doppler US were significantly higher in patients with proven angiographic RAS (3.44±0.66 m/s) than in hypertensive patients with normal renal arteries at angiography (0.99±0.35 m/s, P <0.0001) and normotensive healthy children (1.04±0.23 m/s, P <0.0001). With the use of multiple views, and the experience acquired with practice, false-negatives or false-positives due to the geometry of the renal artery can be avoided. Nevertheless, very distal stenosis can be missed by Doppler US. Received October 30, 1995; received in revised form April 16, 1996; accepted May 14, 1996  相似文献   
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目的:研究阈值下经瞳孔温热疗法(TTT)对视网膜组织学的效应。方法:对正常视网膜色素的兔眼进行TTT,通过1个810nm激光二极管产生直径为1.2mm能量为50mW的光斑,持续时间为15、30和60秒。4周后进行荧光血管造影并摘除眼球,通过电子显微镜和免疫组化染色来检查。  相似文献   
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Two anti-tumor monoclonal antibodies, L6 (anticarcinoma) and 1F5 (anti-B lymphoma), were covalently linked to alkaline phosphatase (AP), forming conjugates that could bind to the surface of antigen-positive tumor cells. The conjugates were capable of converting a relatively noncytotoxic prodrug, etoposide phosphate (EP), into etoposide--a drug with significant antitumor activity. In vitro studies with a human colon carcinoma cell line, H3347, demonstrated that while EP was less toxic than etoposide by a factor of greater than 100, it was equally toxic when the cells were pretreated with L6-AP, a conjugate that bound to the surface of H3347 cells. The L6-AP conjugate localized in H3347 tumor xenografts in nude mice and histological evaluation indicated that the targeted enzyme (AP) was distributed throughout the tumor mass. A strong antitumor response was observed in H3347-bearing mice that were treated with L6-AP followed 18-24 hr later by EP. This response, which included the rejection of established tumors, was superior to that of EP (P less than 0.005) or etoposide (P less than 0.001) given alone. The IF5-AP conjugate did not bind to H3347 cells and did not enhance the toxicity of EP on these cells in vitro. In addition, IF5-AP did not localize to H3347 tumors in nude mice and did not demonstrate enhanced antitumor activity in combination with the prodrug.  相似文献   
6.
Sixty vancomycin-resistant vanA mutant Enterococcus faecium (VRE) isolates, collected during a 40-month period from 48 patients hospitalized in a French Cancer Referral Center, were typed by using random amplified polymorphic DNA (RAPD), and the results were compared with those previously obtained by typing with SmaI pulsed-field gel electrophoresis (PFGE), which is currently recognized as the "gold standard." The discriminating power of RAPD typing, with seven primers and 11 combinations of primers, was tested on 18 strains, and only the most discriminating combination was further tested on the whole collection. We compared the epidemiological usefulness of RAPD typing of 60 clinical VRE isolates with that of SmaI PFGE typing. With primers AP4 and ERIC1R, RAPD generated 30 patterns versus the 36 patterns generated by SmaI PFGE. However, this did not hamper the epidemiologically correct clustering of 15 related strains and the detection of multiple colonization in nine patients. We conclude that this simple RAPD technique is well suited to the epidemiological typing of VRE and the monitoring of its nosocomial spread.  相似文献   
7.
PURPOSE: The aim of this study was to document the surgical and intensive care methods used in six extensively burned children (EBC), ie, total body surface area (TBSA) burned over 70% or TBSA with deep burns over 60%, treated with cultured epidermal autografts (CEA). METHODS: Six EBC, with a mean age of 7.5 years (range, 2.5 to 12) received CEA. Their mean TBSA burned was 82% (range, 70-94) with 74% (range, 60-90) of TBSA with deep burns. All sustained flame burns and inhalation injuries. RESULTS: The survival rate was six of six. The average initial and final engraftment rates of CEA were, respectively, 79% (range, 70 to 95) and 84% (range, 72 to 100). CEA definitively covered 45% (range, 18 to 57) of TBSA for a mean cost per child of $80,000 (range, 55,000 to 110,000). CONCLUSION: Even if CEA are expensive, such engraftment rates and survival ratio results make them an excellent alternative wound covering method for EBC when donor sites for widely meshed autografts are exhausted.  相似文献   
8.
Liver slice viability is extended to 96 h for rat, expanding the use of this in vitro model for studying mechanisms of injury and repair, including pathways of fibrosis. The contributing factors to increased organ slice survival consist of the use of a preservation solution for liver perfusion and slice preparation, obtaining rats that are within the weight range of 250-325 g, placing a cellulose filter atop the titanium mesh roller-insert to support the slice, and maintaining the slices in an optimized culture medium which is replaced daily. The liver slices remain metabolically active, synthesizing adenosine triphosphate (ATP), glutathione, and glycogen, and exhibit preserved organelle integrity and slice morphology. Slice preparation results in 2-cut surfaces which likely triggers a repair and regenerative response. The fibrogenic pathways are evident by the activation of stellate cells, the proliferation of myofibroblast-like cells, and an increased collagen deposition by 48 h. Markers indicative of activated stellate cells, alpha-smooth muscle actin, collagen 1a1, desmin, and HSP47 are substantiated by real time-PCR. Increased staining of alpha-smooth muscle actin initially around the vessels and by 72-96 h in the tissue is accompanied by increased collagen staining. Microarray gene expression revealed extracellular matrix changes with the up-regulation of cytoskeleton, filaments, collagens, and actin genes; and the down-regulation of genes linked with lipid metabolism. The improvements in extending liver slice survival, in conjunction with its three-dimensional multi-cellular complexity, increases the application of this in vitro model for investigating pathways of injury and repair, and fibrosis.  相似文献   
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