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31.
To determine if cardiac allograft outcome is improved among patients with fewer HLA-DR mismatches with their donors, we studied 132 recipients of a primary cardiac allograft who were transplanted between December 1985 and December 1991. These recipients and their donors all had high-confidence-level serological HLA-DR typing, previously shown to correlate highly with DNA DR typing. Patients were divided in two groups based on the HLA-DR mismatch with their donors. Group I consisted of 78 patients with 1 or zero DR mismatch and group II of 54 patients with 2 DR mismatches. Allograft outcome measurements included incidence of moderate rejection, incidence of allograft vasculopathy at 12 months, cardiac function measured as left ventricular ejection fraction (LVEF) and cardiac index (CI), and actuarial graft survival up to 7 years. Groups I and group II were not different with regard to recipient age, donor age, ischemia time, pulmonary vascular resistance, sex, or PRA greater than 0%. Group II had a higher incidence of moderate rejection on the first-week biopsy (47% vs. 25%, P = 0.019), and during the first month (84% vs. 58%, P = 0.006), but no difference was found in frequency of rejection from months 2 to 12. LVEF was not different in the groups at any point. CI was better in group I at 12 months (2.76 vs. 2.5, P = 0.03). No statistically significant difference was found in incidence of allograft vasculopathy (17% vs. 26%, P = 0.204). Actual graft survival at 1 year was better for group I (91% vs. 74%, P = 0.008), and actuarial graft survival at 6 years also favored group I (76% vs. 56%, P = 0.04). Using high-confidence-level serological HLA-DR typing assignments we demonstrated that HLA-DR mismatching correlates highly with cardiac allograft outcome. Implications are that heart transplant survival could be improved if prospective matching were feasible and prioritized or if immunosuppression were tailored to the HLA-DR match.  相似文献   
32.
We have examined acetaminophen (paracetamol) dosing for outpatient management of posttonsillectomy pain in children. Forty children, 5-15 years of age, undergoing tonsillectomy and their parents were randomly assigned to use a scheduled administration of acetaminophen in weight appropriate doses, 60 mg.kg-1.24h-1 orally, 90 mg.kg-1.24h-1 rectally, or to use acetaminophen 'as needed' according to present standards (control group). Postoperative pain was assessed by the child using the poker chip tool for the first three days after discharge. The prevalence of pain amongst all the children was high. The second day after discharge 22%-64% of the children in the study group and 36%-73% of the children in the control group rated severe pain. Recommended dose ranges of acetaminophen do not provide sufficient pain relief in children following tonsillectomy. Further studies are required to determine, whether higher doses of acetaminophen or analgesics with different analgesic properties will lead to improved analgesia in children following tonsillectomy.  相似文献   
33.
Self-selected food intake of 15 reduced-obese women living in a metabolic ward was studied for 14 consecutive days to determine the effect of exercise and other metabolic and behavioral variables on energy intake. A choice of prepared food items were offered at breakfast, lunch and dinner, and a variety of additional food items were available continuously 24 h/day. Subjects performed either moderate intensity aerobic exercise (A-EX) (n = 8) expending 354 +/- 76 kcal/session or low intensity resistance weight training (R-EX)(n =7) expending 96 +/- kcal/session, 5 days/week. Mean energy intakes (kcal/day, +/- SEM) of the exercise groups were similar: 1867 +/- 275 for A-EX, 1889 +/- 294 for R-EX. Mean energy intakes of individuals ranged from 49 to 157% of the predetermined level required for weight maintenance. Resting metabolic rate per kg 0.75 and the Eating Inventory hunger score contributed significantly to the between subject variance in energy intake, whereas exercise energy expenditure did not. Regardless of exercise, eight women consistently restricted their energy intake (undereaters), and seven other consumed excess energy (overeaters). Overeaters were distinguished by higher Eating Inventory disinhibition (P = 0.023) and hunger (p = 0.004) scores. The overeaters' diet had a higher fat content 34 +/- 1% (p = 0.007). Also, overeaters took a larger percentage of their daily energy, than that of undereaters, 27 +/- 1 energy intake in the evening, 13 +/- 2%, compared to undereaters, 7 +/- 1% (p = 0.005). We conclude that the Eating Inventory is useful for identifying reduced-obese women at risk of overeating, and these individuals may benefit from dietary counseling aimed at reducing fat intake and evening snacking.  相似文献   
34.
Regeneration of skeletal muscle was studied in the sea bream Sparus aurata, in which extensive post-larval muscle hyperplasia contributes to its large adult size, and in the zebrafish Brachydanio rerio, which shows little post-larval hyperplasia and reaches only a small adult size. Small mechanical lesions of body wall muscle were made under general anaesthesia, and the progress of subsequent regeneration was assessed at various intervals by histology and electron microscopy (for general morphology), by immunostaining for desmin and myosin isoforms (to identify the phenotype of new fibres), and by 5'-bromo-2'-deoxyuridine (BrdU) incorporation (to identify proliferating cells). Despite the difference in normal growth-related hyperplasia in these fish, a vigorous regeneration occurred in both species, giving rise to new fibres with an initial myosin composition that differed from that in mature fast-white fibres. However, species differences in myosin expression in these fibres suggest that they may have derived from different myoblast populations. In sea bream, myosin expression in regenerating fibres resembled that seen in new fibres produced in post-larval white muscle, whereas in the zebrafish it resembled that of the primitive monolayer fibres formed during embryonic development. Subsequently, most regenerating fibres gradually transformed into the mature fast-white phenotype in both species.  相似文献   
35.
36.
The disease management approach to patient care seeks to coordinate resources across the healthcare delivery system. The growing interest in evidence based medicine and outcomes, and a commitment to integrated care across the primary, secondary, and community care sectors, all contribute to making disease management an attractive idea. A combination of patient education, provider use of practice guidelines, appropriate consultation, and supplies of drugs and ancillary services all come together in the disease management process. But its effectiveness is largely untested, so evaluation is essential.  相似文献   
37.
The present study proposes a detection technique for delaminations in a laminated beam. The proposed technique optimizes the spatial distribution of harmonic excitation so as to magnify the difference in response between the delaminated and intact beam. The technique is evaluated by numerical simulation of two-layered aluminum beams. Effects of measurement and geometric noise are included in the analysis. A finite element model for a delaminated composite, based on a layer-wise laminated plate theory is used in conjunction with a step function to simulate delaminations  相似文献   
38.
Cerebral malaria     
There is no established protocol for selection among the different retentive material-attachment combinations for clasps other than tradition or laboratory preference. Various wrought-wire, cast-metal, and thermoplastic materials were subjected to several fabrication procedures and tested in a custom-designed force displacement apparatus. The wrought wires included ADA Spec. No. 7 type I and type II alloys and other precious and nonprecious alloys. A graphic means was devised to allow the rational selection of wrought-wire clasp-arm combinations for placing clasps on canine and premolar teeth. Guidelines for using straight wire data for curved wire applications are indicated.  相似文献   
39.
A prospectively studied group of 55 uncemented Press Fit Condylar total knee arthroplasties was compared retrospectively with a matched group of 51 cemented Press Fit Condylar total knee arthroplasties at a mean of 10 years after operation. For the cemented group, the pain and function scores improved from 32 and 45 preoperatively to 95 and 77, respectively. For the uncemented group the scores improved from 33 and 50 preoperatively to 93 and 60, respectively. There were 10 revisions in the uncemented group for femoral or tibial aseptic loosening or osteolysis compared with two revisions in the cemented group. Exclusive of problems related to patellar metal backing, survival to revision for aseptic failure or radiographic loosening was 72% in the uncemented group and 94% in the cemented group at 10 years. A significantly higher revision rate was found in the uncemented compared with cemented total knee arthroplasty of the Press Fit Condylar design.  相似文献   
40.
The multiple genetic hit model of cancer predicts that normal individuals should have stable populations of cancer-prone, but noncancerous, mutant cells awaiting further genetic hits. We report that whole-mount preparations of human skin contain clonal patches of p53-mutated keratinocytes, arising from the dermal-epidermal junction and from hair follicles. These clones, 60-3000 cells in size, are present at frequencies exceeding 40 cells per cm2 and together involve as much as 4% of the epidermis. In sun-exposed skin, clones are both more frequent and larger than in sun-shielded skin. We conclude that, in addition to being a tumorigenic mutagen, sunlight acts as a tumor promoter by favoring the clonal expansion of p53-mutated cells. These combined actions of sunlight result in normal individuals carrying a substantial burden of keratinocytes predisposed to cancer.  相似文献   
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