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61.
One biceps muscle of 8 patients with Duchenne muscular dystrophy was injected at 55 sites with a total of 55 million viable, purified, and contamination-free normal myoblasts (myoblast transfer). The other biceps of each patient was injected with a placebo to serve as a control. The procedure was blinded to the patients, parents, and investigators. Myoblasts derived from a biopsy specimen of the fathers were cultured and purified under strict conditions and carefully screened for microbial contamination. All patients received cyclophosphamide for immunosuppression for 6 or 12 months. No serious complications were observed after myoblast transfer, indicating that the procedure is safe. The overall therapeutic efficiency of myoblast transfer was poor as judged by the results in maximal voluntary force generation, dystrophin content of the muscle, magnetic resonance imaging of the muscle, and the lack of donor-derived DNA and dystrophin messenger RNA in the injected muscle. An improved efficiency of the take of myoblasts might be achieved by using younger cells and injecting the myoblasts with a myonecrotic agent (to increase the prevalence of regeneration) and a basal laminal fenestrating agent.  相似文献   
62.
The in vivo functional characteristics of continuous arteriovenous hemofiltration (CAVH) were studied in 21 intensive-care patients with acute renal failure. FH-66 hemofilters were applied. The relationships between prefilter blood pressure (BP), blood flow (QB) and filtration rate (QF) were evaluated by stepwise clamping of the arterial access and simultaneous measurements of these parameters. The correlations between BP and QB, and between QB and QF, were linear (p less than 0.001). The total pressure drop across the extracorporeal circuit was 90 +/- 12 mmHg with Scribner shunt and 70 +/- 13 mmHg with femoral catheters as vascular access. The relative pressure drops across arterial access, hemofilter and venous access for Scribner shunt and for femoral catheter were 30%, 43% and 27% and 12%, 74% and 14%, respectively. At a given BP, QB was lower and transmembrane filtration pressure (TMP) higher in CAVH with Scribner shunt. QB was 102 +/- 38 ml/min; QF was 20 +/- 7 ml/min. The effects of hemofilter geometry and membrane material on functional parameters of CAVH were evaluated by applying four hemofilters (Amicon D-20 HP, D-30 HP, Gambro FH-66, Fresenius AV-400) consecutively in the same patient. The filters were different with respect to hollow fiber length, its internal diameter, number of fibers and membrane material. BP, hematocrit (Hct) and plasma protein remained constant during measurements. QB increased with decreasing filter resistance. QF did not increase with increasing QB. QF was also not closely related to membrane surface area. The hydraulic permeability (Lp) had a major impact on QF.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
63.
Regional peripheral vascular resistance, transcutaneous oxygen pressure and blood pressure were studied in seven normotensive, chronically haemodialysed patients with renal anaemia before and after 3 and 12 months of rHuEpo therapy. Haematocrit increased from 21% to 33% within 3 months of commencing therapy, and remained stable throughout the following observation time. Though regional blood flow of the calf was markedly reduced after 3 and 12 months of rHuEpo compared to pretreatment values, transcutaneous oxygen pressure was significantly increased after 3 months and remained constantly elevated after 12 months. Mean arterial blood pressure increased significantly by 7.3 mmHg after 3 months of rHuEpo treatment but did not reach hypertensive values and was no longer different from pretreatment values 12 months after the start of rHuEpo. Results of peripheral haemodynamic studies were compared to those obtained by measurement of central haemodynamics in four further normotensive anaemic patients. In these patients cardiac output decreased, total peripheral vascular resistance increased and blood pressure increased slightly (by 5.5 mmHg) when a haematocrit of 37% was reached after 8 weeks of rHuEpo therapy. These effects were partly reversed when the maintenance haematocrit decreased to 32% (after 16 weeks of rHuEpo). In summary rHuEpo treatment induced a long-term increase of the total and regional peripheral resistance, an increase of blood pressure within the normal range, and a decrease in cardiac output. Despite these changes tissue oxygenation improved.  相似文献   
64.
The long-held belief that venous oxygen tension mirrored tissue oxygen tension became suspect in the 1960s when new instrumentation consistently showed that tissue oxygen tension was 10 to 30 torr less than venous oxygen tension. Moreover, a countercurrent of oxygen exchange between terminal arteries and veins was shown to exist. Despite this conflict in scientific theory, however, monitoring venous oxygen tension as a means to control hypothermic cardiopulmonary bypass has been repeatedly urged, since myocardial acidosis is clearly extremely detrimental. This study of the relationship between venous oxygen tension during hypothermic bypass and a concurrent increment in lactacidemia yields strong objective evidence to support the use of on-line venous oxygen tension monitoring to guide perfusion. In a random series of 36 patients, venous blood samples were drawn at five preselected intervals during operation and were analyzed for pH, carbon dioxide tension, oxygen tension, lactic acid, hematocrit, and base excess. Analysis of the data revealed that venous pH and base excess showed no correlation to venous oxygen tension. However, lactic acid showed a strong correlation with venous oxygen tension, with a correlation coefficient of 0.4338 at a confidence level of p less than 0.0001. If the patients were divided into three clinically pertinent groups based on the lowest venous oxygen tension recorded, a strong relationship between venous oxygen tension and lactic acid emerged. If the lowest measurement of venous oxygen tension was greater than 35 mm Hg (group A), the mean rise in lactic acid was only 0.12 microns/ml. If the lowest measurement was between 30 and 34 mm Hg (group B), the mean rise was 0.64 microns/ml. Whereas, if any venous oxygen tension value fell below 30 mm Hg (group C), the mean rise in lactic acid was 2.56 microns/ml. Analysis of variance showed that group C values were significantly different from groups A and B values (p less than 0.0002). A scientific hypothesis relating venous oxygen tension to adequate tissue oxygenation is proposed. Use of venous oxygen tension monitoring with the goal to maintain the level above 35 mm Hg is strongly supported by this study.  相似文献   
65.
Congenital epulis of the newborn is a rare gingival tumor that occurs along the alveolar ridge. We report the prenatal sonographic and postnatal MR imaging findings in an infant with maxillary and mandibular congenital epulides.  相似文献   
66.
Antagonism of the histamine (H2) receptor reduces antinociception induced by naloxone-resistant foot-shock, naloxone-sensitive foot-shock, and morphine with a rank-order potency similar to their H2 antagonism. The antimetabolic glucose analog 2-deoxy-D-glucose (2DG) produces antinociceptive and hyperphagic responses that dissociate from each other and are in part mediated by opioid systems. The present study determined the effects of the brain-penetrating H2 receptor antagonist zolantidine (ZOL) on 2DG antinociception on the tail-flick and jump tests, as well as on 2DG hyperphagia, in rats. ZOL (0.01-1 mg/kg) potentiated the antinociceptive responses induced by a moderate (450 mg/kg) dose of 2DG, but had lesser effects upon antinociception induced by a lower (100 mg/kg) 2DG dose. ZOL itself slightly increased jump thresholds, but not tail-flick latencies. Combinations of ZOL and 2DG produced supraadditive antinociception, even though ZOL failed to significantly shift the 2DG dose-response curve to the left. In contrast, ZOL failed to alter basal intake or 2DG hyperphagia, supporting previous evidence implicating the H1 but not the H2 receptor in these effects. These results further dissociate the antinociceptive and hyperphagic effects of 2DG, and also support previous results indicating both pro- and antinociceptive roles for H2 receptors.  相似文献   
67.
Summary Percutaneous angioplasty is a well-established method of treating arterial stenoses and occlusions in various regions. In the carotid area this technique is still under discussion. The successful application of angioplasty in eight patients with carotid artery stenoses is reported.Adapted from a paper presented at XII European Congress for Neuroradiology in Prague, 27–29 September, 1984  相似文献   
68.
In 73 healthy (group I) and 32 children and juveniles with insulin dependent diabetes mellitus (IDDM, group II) urinary albumin excretion is determined by radioimmunoassay (RIA). In both groups albumin excretion is observed in every urine sample when measured by RIA (mean +/- SD: group I: 7-19 h: 5.17 +/- 5.28 mg, 19-7 h: 3.86 +/- 4.00 mg, 24 h: 9.03 +/- 8.60 mg; group II: 7-19 h: 6.68 +/- 6.86 mg, 19-7 h: 3.46 +/- 2.82 mg, 24 h: 10.13 +/- 9.25 mg). No significant difference is detected between the values of the two groups. However in diabetic patients a significant difference is observed between diurnal and nocturnal urinary albumin excretion. Microalbuminuria is defined as an albumin excretion above 30 mg/d and is present in 6.9% of the values in group I and in 3.1% in group II. The physiological limits of microalbuminuria in children and juveniles compared to adults and several methods of urine sampling are discussed.  相似文献   
69.
Reductive activation of 2-nitroimidazoles in the presence of bovine serum albumin (BSA) led to binding of the nitroheterocycles to the protein. The binding was most efficient to BSA in which protein disulfides had been reduced to thiol groups. Protein thiols were at least twenty times more efficient than other protein, RNA or DNA nucleophiles in binding the reductively-activated nitroheterocycles. This result is of practical importance in the development of immunoassays for 2-nitroimidazoles as hypoxia markers in normal and tumor tissue.  相似文献   
70.
A woman with rheumatoid arthritis who underwent total knee arthroplasty is described. The implant became infected with Staphylococcus epidermidis and she received a prolonged course of postoperative antistaphylococcal antibiotics. Four months postoperatively she developed a calf ulcer that grew Pseudomonas aeruginosa and required further antibiotic therapy. One year later she presented with a painful, swollen knee with radiographic findings suggesting loosening of the prosthetic knee implant. Arthrocentesis cultures grew Candida albicans. She was treated with arthrodesis, amphotericin B, 5-fluorocytosine, and ketoconazole and remains free of infection 21 months after removal of the prosthesis. The clinical course of 6 other cases of Candida prosthetic joint infections is reviewed.  相似文献   
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