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排序方式: 共有1384条查询结果,搜索用时 15 毫秒
1.
Effect on mortality of inhalation injury   总被引:5,自引:0,他引:5  
A retrospective analysis of 1,018 consecutive admissions with cutaneous burn injury over 32 months was carried out. Mortality probabilities as related to age, per cent TBSA burn, and presence of inhalation injury are presented. Incidence of and mortality from inhalation injury both rose with increasing burn area. The incidence of inhalation injury also rose with advancing age; mortality was lowest in the 5- to 14-year old age group and highest in those more than 59 years of age.  相似文献   
2.
In this study we have assessed the hypothesis that there is a postreceptor defect in glucose metabolism that makes the severely burned patient unable to oxidize glucose efficiently as an energy source. The intracellular pyruvate pool was labeled by the infusion of 3-13C-lactate, and expired CO2 production and isotopic enrichment of both pyruvate and CO2 were determined to calculate the rate of pyruvate production and oxidation. 6,6-d2-Glucose and 15N-alanine were infused simultaneously to relate pyruvate kinetics and oxidation to glucose and alanine kinetics. Five normal volunteers and 10 severely burned patients (mean of 80% +/- 5% body surface burned) were studied in the basal state and during continuous (unlabeled) glucose infusion. Also, the effect of dichloroacetate, which normally stimulates pyruvate dehydrogenase activity, was assessed in both volunteers and patients. The burned patients had many of the classic metabolic responses to severe injury, including significant increases in resting energy expenditure, glucose production, and alanine release from protein breakdown. However, rather than being inhibited, the rate of pyruvate oxidation was increased approximately 300% in burned patients. Although the patients had an elevated mean concentration of lactate, stemming from increased lactate production, no deficit in pyruvate dehydrogenase activity was evident. Rather, the high rate of lactate production was apparently a consequence of the high rate of glycolysis. On the other hand, the direct pathway for synthesis of glycogen from infused glucose appeared to be impaired in burned patients. In both volunteers and patients, dichloroacetate stimulated the percent of pyruvate directed to oxidation, thereby reducing the conversion of pyruvate to other fates, including lactate. However, because there was no deficit in pyruvate dehydrogenase activity in the patients compared with normal volunteers before dichloroacetate treatment, no unique effect of dichloroacetate on glucose or protein kinetics was observed in burned patients. From these results we conclude that if there is a postreceptor defect in glucose metabolism in burned patients, it involves the pathway of direct glycogen synthesis and not the pathway of oxidation.  相似文献   
3.
The hypercatabolism after massive pediatric burns has been effectively treated with recombinant human growth hormone, an anabolic agent that stimulates protein synthesis and abrogates growth arrest. While experimental studies have shown increased potential for fibrosis induced by growth hormone therapy, adverse effects on human scars have not been investigated. Our aim was to evaluate hypertrophic scar formation in 62 patients randomized to receive injections of 0.05 mg/kg/day of recombinant human growth hormone or placebo, from discharge until 1 year after burn. Scar scales were used to evaluate scar-severity at discharge, 6, 9, 12, and 18-24 months after burn, by three observers blinded to treatment. Computer-assisted planimetry allowed quantification of percentage of hypertrophic scar formation. Types I and III collagens were localized and quantified in scars and normal skin of patients from both groups, using immunohistochemistry with confocal laser microscopy analysis. Insulin-like growth factor-1 blood levels helped assess compliance. Statistical analysis showed that scar hypertrophy significantly increased from 6 to 12 months after injury in both groups, while decreasing at 18-24 months postburn. Types I and III collagens were statistically increased in the reticular layer of scars from both groups when compared to paired normal skin. Insulin-like growth factor-1 was significantly increased in the recombinant human growth factor-treated group. No differences were seen when recombinant human growth factor and control groups were compared using the scar scales, planimetry, or immunohistochemistry. We concluded that recombinant human growth hormone therapy did not adversely affect scar formation and should not contraindicate the administration of recombinant human growth hormone as a therapeutic approach to severely burned children.  相似文献   
4.
OBJECTIVE: Two forms of recombinant growth hormone that accelerate the healing of skin graft donor sites in severely burned children were evaluated. SUMMARY BACKGROUND DATA: Growth hormone has been shown to reduce wound healing times in burned pediatric patients. Through genetic engineering, several different forms have been synthesized; however, not all are marketed currently. Two forms of growth hormone were used in these studies, Protropin (Genentech, Inc., San Francisco, CA), a commercially available product that possesses a N-terminal methionine residue not found in the second form Nutropin (Genentech, Inc., San Francisco, CA), which, as yet, is not commercially available. Through the use of recombinant human growth hormone, rapid wound healing may reduce the hypermetabolic period, the risk of infection, and accelerate the healing of donor sites used for grafting onto burned areas. The two structurally different forms of growth hormone were tested for their efficacy in healing donor sites in severely burned children. METHODS: Forty-six children, with a > 40% total body surface area and > 20% total body surface area full-thickness burn were entered in a double-blind, randomized study to receive rhGH within 8 days of injury. Twenty received (0.2 mg/kg/day) Nutropin or placebo by subcutaneous or intramuscular injection beginning on the morning of the initial excision. Eighteen patients who failed the entry criteria for receiving Nutropin received Protropin therapeutically (0.2 mg/kg/day). Donor sites were harvested at 0.006 to 0.010 inches in depth and dressed with Scarlet Red impregnated fine mesh gauze (Sherwood Medical, St. Louis, MO). The initial donor site healing time, in days, was reached when the gauze could be removed without any trauma to the healed site. RESULTS: Donor sites in patients receiving Nutropin (n = 20) or Protropin (n = 18) healed at 6.8 +/- 1.5 and 6.0 +/- 1.5 (mean +/- SD) days, respectively, whereas those receiving placebo (n = 26) had a first donor site healing time of 8.5 +/- 2.3 days. Both groups receiving rhGH showed a significant reduction in donor site healing time compared with placebo at p < 0.01. When subgroups were compared, no difference in healing times could be shown with regards to age or time of admission after injury. CONCLUSION: Our results indicate that both forms of rhGH are effective in reducing donor site healing time compared with placebo and suggest that accelerating wound healing is of clinical benefit because the patients' own skin becomes rapidly available for harvest and autografting. With this increase in the rate of wound healing, the total length of hospital stay can be reduced by more than 25%.  相似文献   
5.
This randomized phase II study was designed to evaluate the activity of intravenous 6-thioguanine (6-TG) as a single agent and the combination of cisplatin and 5-fluorouracil (5-Fu) modulated by oral leucovorin (PFL) in patients with advanced non-small cell lung cancer (NSCLC). Eligible patients had measurable or evaluable stage III B or IV NSCLC, had no received prior chemotherapy and had a performance status of 0-2. Patients were randomized to treatment with intravenous 6-TG at 55 mg/m2 administered over 30 minutes for 5 consecutive days and repeated every 35 days, or PFL chemotherapy with cisplatin 100 mg/m2 on day 1, 5-FU 800 mg/m2/day as a continuous intravenous infusion over 5 days and oral leucovorin administered at 100 mg every 4 hours during the entire duration of the cisplatin and 5-FU infusions. PFL was repeated every three weeks. Ninety-five eligible patients were randomized, 46 to 6-TG and 49 to PFL. Response rates were 4% for 6-TG (95% confidence interval 0.5%-14.8%, 1 partial, and 1 complete response) and 29% (16.6%-43.3%) for PFL (all partial). The median time to treatment failure was 2 and 4 months, respectively, and the median survival times were 6 and 10 months, respectively. Toxicities with 6-TG were, generally, mild to moderate but severe or life-threatening granulocytopenia was observed in 21% of patients. With PFL, mucositis was dose-limiting, and 78% of patients had severe or life-threatening mucositis. This led to dose reduction of 5-FU and leucovorin during subsequent cycles or treatment termination in 82% of patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
6.
Early excision of deep burns has been advocated; however, it is difficult to clinically determine the depth of scald burns during the early postburn period. This prospective, randomized study was designed to determine whether early excision was superior to conservative treatment of scald injuries. Patients with scald injuries (which were not caused by grease) of clinically indeterminant depth were randomized to early (n = 12) or late (n = 12) excision; all patients with obvious superficial and full-thickness injuries were excluded. In the early excision group, all deep wounds were tangentially excised and grafted within 72 hours of admission, whereas in the late treatment group wounds were excised and grafted after 2 weeks had passed since injury. Area excised, postburn day of excision, percent graft take, operating-room time, blood replacement, incidence of infection, and length of hospital stay were compared. No patient experienced a significant wound infection or systemic sepsis. A significantly smaller area of excision was necessary for those patients who were treated with delayed surgery, and concomitant decreases in operating-room time and blood loss were observed. Notably, only one half of the patients who were randomized to the delayed excision group ultimately required surgical intervention to achieve wound closure. Graft take was comparable for both groups, as was length of hospital stay. Early clinical evaluation of scald injuries appears to be equivocal, and later evaluations reveal a less severe injury. Financial gains can be made when surgical excision of scald injuries is delayed until 2 weeks after injury because of a related reduction in hospital expenditures.  相似文献   
7.
OBJECTIVE Little information is available regarding the regulation of serum acid-labile subunit (ALS) in human disease. We have studied alterations in serum ALS of the insulin-like growth factor (IGF) ternary complex in children with untreated insulin-dependent diabetes mellitus (IDDM) and subjects with severe burns before and after insulin therapy. In addition, we have investigated the effect of insulin plus GH on serum ALS in burn patients. DESIGN Serum samples were obtained from children with newly diagnosed and untreated IDDM before the initiation of insulin therapy and 1 month thereafter. Serum samples were also obtained from adult patients with severe burns who were on a continuous infusion of a carbohydrate-rich enteral diet via nasogastric and duodenal catheters under basal conditions, after a 1-week period of continuous insulin infusion, and after an additional week of insulin plus recombinant GH. PATIENTS Twenty children and adolescents with untreated IDDM, aged 1.2–16 years, and 6 young adult patients with severe burns aged 17–28 years were studied longitudinally. Control sera were obtained from age, sex and pubertal status matched subjects (for children with IDDM) and from fed healthy adults. MEASUREMENTS Serum insulin, GH, cortisol and IGF-I were measured by radioimmunoassay, and serum ALS levels were assessed by Western immunoblot before and after treatment periods. RESULTS Serum ALS levels were lower in untreated children with IDDM (69 ± 6% of control children). Insulin therapy significantly increased serum ALS (79 ± 5%, P<0.05) in these children. Patients with severe burns also had lower serum ALS levels (79 ± 10% of control adults). After one week of insulin therapy serum ALS levels increased to 90 ± 15% of control values (P<0.05). Addition of GH to insulin therapy for another week did not significantly further increase serum ALS levels (95 ± 27%). Serum IGF-I concentrations increased nearly 2.5-fold in diabetic subjects and fourfold in burn subjects at the end of the study periods. There were no proteolytic fragments of ALS in the sera studied. The deglycosylation pattern of ALS did not differ between diabetic and control sera. CONCLUSION Serum ALS levels were diminished in children with untreated IDDM and were partially restored after the initiation of insulin therapy. Serum ALS levels were also diminished in patients with severe burn injury and restored by insulin treatment. Addition of GH to insulin therapy did not significantly increase serum ALS levels over levels obtained during insulin therapy alone. These decreases in serum ALS were smaller than the decrease in serum IGF-I concentrations in both conditions, suggesting that IGF-I is the limiting factor for the ternary complex formation in the catabolic states. Insulin may regulate circulating ALS levels in catabolic states and helps to restore the IGF system.  相似文献   
8.
9.
Neuronal population of area 4 during the life span of the rhesus monkey   总被引:1,自引:0,他引:1  
One right or left area 4 of each of 19 rhesus monkeys, ranging in age from 1 day to 35 years, was processed (frozen sectioned at 30 or 40 microns) for light microscopic analysis to assess age-related changes in the neuronal population. All neurons were examined regardless of their size. In addition, Betz cells were analyzed separately; to be regarded as Betz cells, pyramidal somata had to display a minimum height of 38 microns. A significant loss of approximately one-third was observed in the total number of neurons in maturing monkeys (less than 5.5 years). In contrast, in maturing rhesus monkeys significant increases with age were observed in the mean number of Betz cells, and in the means of Betz cell area, height, width, perimeter, and estimated volume. In adult monkeys (greater than 4.5 years), no age-associated loss of neurons was observed. Also, no loss of Betz cells occurred, although the perimeter, area, and estimated volume of Betz cells decreased slightly, but significantly, with increasing age in adult monkeys. Lipofuscin granules were discernable in Betz cells beginning at the age of 5 years and their number increased with increasing age. In the older rhesus monkeys, the lipofuscin granules were so large and numerous that in some Betz cell somata they displaced the nucleus from its usual location in the center of the cell. No age-related change in thickness of area 4 was found.  相似文献   
10.

Background  

Painless, rapid, controlled, minimally invasive molecular transport across human skin for drug delivery and analyte acquisition is of widespread interest. Creation of microconduits through the stratum corneum and epidermis is achieved by stochastic scissioning events localized to typically 250 μm diameter areas of human skin in vivo.  相似文献   
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