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31.
Fluphenazine decanoate is commonly used as part of maintenance treatment of schizophrenia, but its pharmacokinetics are poorly understood. We administered a single intramuscular dose of fluphenazine decanoate to nine patients and found that plasma fluphenazine level did not decline to 50% of the peak level by day 26 in any of the patients. This means that it has a long half-life measurable in months rather than weeks.  相似文献   
32.
Obesity in youth and middle age and risk of colorectal cancer in men   总被引:5,自引:0,他引:5  
To investigate an association between colon cancer and obesity during early adulthood—a potentially important period in the etiology of this disease—the authors assembled, by computer linkage, a population-based historical cohort of 52,539 men born between 1913 and 1927 residing in Hawaii (USA), for whom weight and height had been recorded in 1942–43 and 1972. Linkage of this cohort to the Hawaii Tumor Registry resulted in the identification of 737 incident cases of colorectal cancer for 1972–86. An average of 3.8 cancer-free controls were matched to each case on month and year of birth and ethnicity of the parents. A case-control analysis in each anatomic subsite of the large bowel revealed that both early and middle-age body mass increased the risk of sigmoid cancer in men in a dose-dependent fashion. The odds ratios (OR) for sigmoid cancer for the highest compared with the lowest tertiles of Quetelet index were: 2.1 (95 percent confidence interval [CI]=1.4–3.2) and 1.7 (CI=1.1–2.5), at ages 15–29 and in prediagnostic years, respectively. These associations were additive and idependent of socioeconomic status. Men who were above the median Quetelet index in 1942 and 1972 had an OR of 2.7 (CI=1.8–4.0), compared with those who were below the median in both periods. This study provides further evidence for an association of obesity with colon cancer in men and suggests that this association is limited to the sigmoid colon and may be related to both early and late events of colon carcinogenesis.The authors are with the Epidemiology Program, Cancer Research Center of Hawaii, University of Hawaii. Address correspondence to Dr Le Marchand, Epidemiology Program, Cancer Research Center of Hawaii, 1236 Lauhala Street, Suite 407, Honolulu, HI 96813, USA. This work was supported in part by Public Health Service grant 5-R29-CA44503 and contract NO1-CN-55424 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services.  相似文献   
33.
BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors.  相似文献   
34.
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA.  相似文献   
35.
Tumor necrosis factor-alpha (TNFalpha) and Fas are induced after traumatic brain injury (TBI); however, their functional roles are incompletely understood. Using controlled cortical impact (CCI) and mice deficient in TNFalpha, Fas, or both (TNFalpha/Fas-/-), we hypothesized that TNFalpha and Fas receptor mediate secondary TBI in a redundant manner. Compared with wild type (WT), TNFalpha/Fas-/- mice had improved motor performance from 1 to 4 days (P<0.05), improved spatial memory acquisition at 8 to 14 days (P<0.05), and decreased brain lesion size at 2 and 6 weeks after CCI (P<0.05). Protection in TNFalpha/Fas-/- mice from histopathological and motor deficits was reversed by reconstitution with recombinant TNFalpha before CCI, and TNFalpha-/- mice administered anti-Fas ligand antibodies had improved spatial memory acquisition versus similarly treated WT mice (P<0.05). Tumor necrosis factor-alpha/Fas-/- mice had decreased the numbers of cortical cells with plasmalemma damage at 6 h (P<0.05 versus WT), and reduced matrix metalloproteinase-9 activity in injured brain at 48 and 72 h after CCI. In immature mice subjected to CCI, genetic inhibition of TNFalpha and Fas conferred beneficial effects on histopathology and spatial memory acquisition in adulthood (both P<0.05 versus WT), suggesting that the beneficial effects of TNFalpha/Fas inhibition may be permanent. The data suggest that redundant signaling pathways initiated by TNFalpha and Fas play pivotal roles in the pathogenesis of TBI, and that biochemical mechanisms downstream of TNFalpha/Fas may be novel therapeutic targets to limit neurological sequelae in children and adults with severe TBI.  相似文献   
36.
BACKGROUND: Wounds, especially in the elderly, can be life threatening. One modality which allegedly increases blood flow (BF) as an aid to heal chronic wounds is electrical stimulation. This technique applies electrical current (ES) across wounds. However, while many studies show positive findings, others do not. The purpose of this investigation was to investigate some of this inconsistency in results by determining the effect of environmental temperature on the circulation of the skin which may negate the effects of electrical stimulation in a clinical setting. MATERIAL/METHODS: Ten people with no wounds, controls (C), and 12 people with wounds (W) were examined in a thermally neutral or cool room (20 degrees C) and a warm room (34 degrees C) to observe the effect of reducing sympathetic vasoconstrictor activity on the response to 5 and 15 mA sine wave biphasic ES delivered by 2x2 cm surface electrodes. RESULTS: C and W subjects showed a greater BF in the skin in a warm room. In group C, after 30 minutes of stimulation at a current of 15 milliamps, BF increased significantly (p<0.05) but by an average of only 4 flux in the cool room. In the warm environment, BF increased significantly (p<0.01) by 19.3+/-7 flux and increased further during the 60 minute recovery phase. In the W group, BF during ES increased much more during stimulation in a warm room compared to a cool room. CONCLUSIONS: The results show that local vasoconstriction due to exposure to a warm global temperature greatly increases the response of the skin the ES.  相似文献   
37.
Nucleotide sequence of the leukotoxin genes of Pasteurella haemolytica A1.   总被引:64,自引:38,他引:26  
A 4.4-kilobase-pair DNA fragment coding for the leukotoxin of Pasteurella haemolytica A1 has been isolated, and its nucleotide sequence has been determined. Two open reading frames, designated lktC and lktA, coding for proteins of 19.8 and 101.9 kilodaltons, respectively, were identified. Expression of the two genes in minicell-labeling experiments resulted in the production of the predicted proteins LKTC and LKTA. By using an antiserum against the soluble antigens of P. haemolytica A1 in Western blot (immunoblot) analysis of total cellular proteins from the Escherichia coli clones, LKTA was identified as an additional antigenic protein. Results from subcloning of the DNA fragment suggested that expression from both lktC and lktA is required for leukotoxin activity, indicating that the leukotoxin of P. haemolytica A1 is encoded by two genes. A comparison of the organization and the DNA sequence of the leukotoxin genes with those of the E. coli alpha-hemolysin genes showed a significant degree of homology between the two loci. This analysis suggested that the leukotoxin genes of P. haemolytica A1 and the E. coli alpha-hemolysin genes may have evolved from a common ancestor and that the two toxins may share similar activities or functional domains or both.  相似文献   
38.
Thirteen amidoderivatives of 3-methyl-3,4-dihydro-6-R-benzo-1,2,4-triazin-3-yl-acetic acids and of 3-methyl-3,4-dihydro-pyrido [3,2-e]/[3,4-e]-1,2,4-triazin- 3-yl-acetic acids were prepared and submitted to a wide pharmacological screening. The dihydrobenzotriazine and dihydropyridotriazine moieties were endowed with a wide pharmacogenic capacity; in fact, several compounds exhibited high antiinflammatory [(I c), (I d), (II d), (V f), (VI f)], diuretic [(I f), (I g), (I h)] and antihypertensive activities [(I d), (III d)], as well as minor effects on the C.N.S.  相似文献   
39.
Summary To define the glucose to insulin dose-response relationship before the onset of diabetes, we studied 22 nondiabetic co-twins of patients with Type 1 (insulin-dependent) diabetes mellitus and nine control subjects. All had intravenous glucose tests at 0.02, 0.1 and 0.5 g/kg and were followedup prospectively for at least 6 years. Seven twins developed diabetes a mean of 7 months later; the remaining 15 are now unlikely to develop diabetes. The seven pre-diabetic twins had higher fasting insulin levels than control subjects (4.2±2.0 vs 1.8±1.8 nmol/l; p<0.05); but lower glucose clearance (1.0±0.5 vs 1.9±0.7 %/min; p<0.05), first phase insulin response at 0.5 g/kg (21.1±23.2 vs 143±50 nmol/l; p<0.0001), and total insulin responses at 0.1 g/kg (p<0.05) and 0.5 g/kg (p<0.00005). Using a curve-fitting programme, the normal glucose to insulin relationship was lost in prediabetic twins who had lower coefficient of determination (R2) than control subjects (p<0.01). In contrast, 15 low-risk twins and their nine control subjects had similar fasting glucose and insulin levels, glucose clearance, R2 and insulin secretory responses to different glucose loads. The positive predictive values of subnormal R2 and subnormal first phase insulin response were 67 % and 58 % respectively. These observations demonstrate an altered glucose to insulin dose-response relationship and loss of maximum insulin secretory response to glucose before the onset of Type 1 diabetes.  相似文献   
40.
C M Lo  S T Fan  C L Liu  W I Wei  R J Lo  C L Lai  J K Chan  I O Ng  A Fung    J Wong 《Annals of surgery》1997,226(3):261-270
OBJECTIVE: The authors report their experience with living donor liver transplantation (LDLT) using extended right lobe grafts for adult patients under high-urgency situations. SUMMARY BACKGROUND DATA: The efficacy of LDLT in the treatment of children has been established. The major limitation of adult-to-adult LDLT is the adequacy of the graft size. A left lobe graft from a relatively small volunteer donor will not meet the metabolic demand of a larger recipient. METHODS: From May 1996 to November 1996, seven LDLTs, using extended right lobe grafts, were performed under high-urgency situations. All recipients were in intensive care units before transplantation with five having acute renal failure, three on mechanical ventilation, and all with hepatic encephalopathy. The median body weight for the donors and recipients was 58 kg (range, 41-84 kg) and 65 kg (range, 53-90 kg), respectively. The body weights of four donors were less than those of the corresponding recipients, and the lowest donor-to-recipient body weight ratio was 0.62:1. The extended right lobe graft was chosen because the left lobe volume was <40% of the ideal liver mass of the recipient. RESULTS: Median blood loss for the donors was 900 mL (range, 700-1600 mL) and hospital stay was 19 days (range, 8-22 days). Homologous blood transfusion was not required. Two donors had complications (one incisional hernia and one bile duct stricture) requiring reoperation after discharge. All were well with normal liver function 5 to 10 months after surgery. The graft weight ranged from 490 g to 1140 g. All grafts showed immediate function with normalization of prothrombin time and recovery of conscious state of the recipients. There was no vascular complication, but six recipients required reoperation. One recipient died of systemic candidiasis 16 days after transplantation and 6 (86%) were alive with the original graft at a median follow-up of 6.5 months (range, 5-10 months). CONCLUSIONS: When performed by a team with experience in hepatectomy and transplantation, LDLT, using an extended right lobe graft, can achieve superior results. The technique extends the success of LDLT from pediatric recipients to adult recipients and opens a new donor pool for adults to receive a timely graft of adequate function.  相似文献   
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