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11.
BACKGROUND: Endothelin, a peptide with strong vasoconstrictive and mitogenic properties, has been found to increase after cardiac transplantation. We therefore assessed the association between its precursor peptide, big endothelin-1, and intimal hyperplasia and coronary flow reserve after heart transplantation. METHODS: Thirty-five patients without hemodynamically significant coronary artery disease after heart transplantation were investigated: Average peak flow velocity in the left anterior descending artery (LAD) was assessed by intracoronary Doppler at baseline as well as after injection of adenosine; coronary flow reserve was calculated as a ratio of both and was corrected for patient age and baseline average peak flow velocity. Lumen, intima + media and total vessel area were measured by intracoronary ultrasound. The plasma concentration of big endothelin-1 in venous blood was determined by radioimmunoassay. RESULTS: Patients with elevated big endothelin-1 levels (>2 fmol/ml) tended to have a decreased corrected coronary flow reserve (2.60 +/- 0.9 vs 3.21 +/- 1.0, p = 0.078). They also had a significantly larger intima + media area (5.82 +/- 2.9 vs 2.37 +/- 2.9 mm(2), p = 0.004) and total vessel area (18.36 +/- 5.8 vs 12.81 +/- 4.8 mm(2), p = 0.012) than those with normal plasma concentrations. CONCLUSIONS: Our study suggests an association between elevated big endothelin-1 plasma levels and the development of intimal hyperplasia and reduction of coronary flow reserve after cardiac transplantation.  相似文献   
12.
The purpose of this study was to evaluate a single-session peer-led safer sex intervention, based on the Information-Motivation-Behavioral Skills theoretical model, for college students residing in campus residence halls. Participants (N = 108) were assigned to either an hour long control or 5-module intervention session. Compared to the control condition, the intervention increased participants’ information and women’s subjective norms about preventative behavior. Both the control and intervention sessions increased intentions to perform preventative behaviors (e.g., keep condoms available). These preliminary results suggest that this intervention is promising for increasing constructs associated with safer sexual behavior and could easily be implemented by residence hall staff.  相似文献   
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14.
OBJECTIVE: To assess the impact of activity restriction (AR) on the incidence of preterm birth in women treated for preterm labor testing negative for fetal fibronectin (fFN). STUDY DESIGN: Women who were diagnosed with preterm labor and tocolyzed with magnesium sulfate were concurrently screened with fFN for the purpose of subsequent management. Included were consenting patients with negative fFN, gestational age 23 0/7-33 6/7 weeks, cervical dilation < or =3 cm, and minimal vaginal bleeding. Patients were randomized to AR or no AR. Primary study outcome was incidence of preterm delivery and interval from randomization to delivery. RESULTS: A total of 73 women with negative fFN were randomized (36 with AR, 37 without AR). The overall preterm birth rate was 40%, with 44.4% of patients with AR and 35.1% of patients without AR delivering preterm, p=0.478. CONCLUSION: Maternal AR did not impact pregnancy outcome. The incidence of preterm birth in symptomatic women testing fFN negative was higher than previously reported.  相似文献   
15.
Thirty-five children with autistic disorder and 17 with autistic-like conditions underwent an exhaustive neurobiological evaluation, and the findings were contrasted with those obtained from various comparison groups. Almost 90 per cent of the children with autistic disorder and autistic-like conditions had major indications of brain damage or dysfunction. Some of those who did not show such abnormalities had a first-degree relative with Asperger syndrome. The rate of abnormality was similar to that of severely mentally retarded children, but in excess of that of normal children. Within the autism group, abnormality rate did not correlate with degree of mental retardation. It is concluded that autism has multiple biological aetiologies and that autistic symptoms in a child should always prompt a thorough medical/neurobiological evaluation.  相似文献   
16.
Research suggests that end-stage renal disease patients with elevated body mass index (BMI) have superior outcomes on dialysis. In contrast, low and high BMI patients represent the highest risk cohorts for kidney transplant recipients. The important question remains concerning how to manage transplant candidates given the potentially incommensurate impact of BMI by treatment modality. We conducted a retrospective analysis of waitlisted and transplanted patients in the United States from 1990 to 2003. We constructed Cox models to evaluate the effect of BMI on mortality of waitlisted candidates and identified risk factors for rapid weight change. We then assessed the impact of weight change during waitlisting on transplant outcomes. Decline in BMI on the waiting list was not protective for posttransplant mortality or graft loss across BMI strata. Substantial weight loss pretransplantation was associated with rapid gain posttransplantation. The highest risk for death was among listed patients with low BMI (13-20 kg/m(2), adjusted hazard ratio = 1.47, p < 0.01). Approximately one-third of candidates had a change in BMI category prior to transplantation. While observed declines in BMI may be volitional or markers of disease processes, there is no evidence that candidates have improved transplant outcomes attributable to weight loss. Prospective trials are needed to evaluate the efficacy of weight loss protocols for candidates of kidney transplantation.  相似文献   
17.
PURPOSE: To compare measured visual field extent for a 6 degrees stimulus (typical size used in studies of infants) with a 1.5 degrees stimulus (similar to the largest size used in Goldmann perimetry) in young infants. METHODS: A total of 120 infants (60 each at 3.5 months and 7 months of age) and 24 adults were tested monocularly with a kinetic perimetry procedure using a black double-arc perimeter. Each subject was tested with either a 6 degrees or 1.5 degrees white sphere, which was mounted on a black wand and moved smoothly toward the intersection of the perimeter arms at 3.4 degrees /s. Visual field extent along each perimeter arm was defined as the median of 2 to 3 measurements of the position of the leading edge of the stimulus when the subject made an eye movement toward the stimulus. RESULTS: The 6 degrees stimulus produced larger measured visual field extent than the 1.5 degrees stimulus in 3.5-month olds (temporal field only) and in 7-month olds (nasal and temporal field), but not in adults. CONCLUSIONS: Using the testing conditions of the present study, increasing stimulus size beyond the largest used in a Goldmann perimeter (approximately 2 degrees) increases measured visual field extent in young infants, but not in adults. This may relate to differences in peripheral summation areas or to differences in attentional factors between infants and adults.  相似文献   
18.
Objective Changes in serum albumin may reflect systemic immunoinflammation and hypermetabolism in response to insults such as trauma and sepsis. Esophagectomy is associated with a major metabolic stress, and the aim of this study was to determine if the absolute albumin level on the first postoperative day was of value in predicting in-hospital complications. Methods A retrospective study of 200 patients undergoing esophagectomy for malignant disease at St. James Hospital between 1999 and 2005 was performed. Patients who had pre and postoperative (days 1, 3, and 7) serum albumin levels measured were included in the study. Patients were subdivided into three postoperative albumin categories <20 g/l, 20–25 g/l, >25 g/l. Logistic regression analysis was performed to calculate the odds of morbidity and mortality according to the day 1 albumin level. Results Patients with an albumin of less than 20 g/l on the first postoperative day were twice as likely to develop postoperative complications than those with an albumin of greater than 20 g/l (54 vs 28% respectively, p < 0.011). Correspondingly, these patients also had a significantly higher rate of Adult Respiratory Distress Syndrome (22 vs 5%, p < 0.001), respiratory failure (27 vs 8%, p < 0.01) and in-hospital mortality (27 vs 6% (p < 0.001). On multivariate logistic regression analysis, day 1 albumin level was independently related to postoperative complications (odds ratios, 0.89: 95%; confidence intervals, 0.83–0.96; p < 0.005). In addition, albumin <20 g/l on the first postoperative day was associated with the need for further surgery and a return to ICU. Conclusion Serum albumin concentration on the first postoperative day is a better predictor of surgical outcome than many other preoperative risk factors. It is a low cost test that may be used as a prognostic tool to detect the risk of adverse surgical outcomes.  相似文献   
19.
Study Objectives . To characterize patient sociodemographics and health, describe vancomycin treatment parameters and clinician-rated outcomes, and determine costs associated with treatment including preparation and administration, adverse events, and toxicity. Design . A prospective study to develop a model for costs associated with antibiotic treatment (vancomycin). Setting . A community hospital. Patients . One hundred adults with active infections. Interventions . Mean duration of therapy was 10 days, and most patients received 2000 mg/day. Serum concentrations were monitored in two of three patients. Detailed cost analyses were completed on a subset of 26 patients selected at random from the overall sample. Measurements and Main Results . Sepsis and skin and skin structure infections were the most common indications for vancomycin therapy. Treatment was effective in 81 patients, failed in 9, and was not evaluable in 10. Thirty-eight percent of patients experienced adverse events attributable to the drug. Phlebitis was common, and red man syndrome, nephrotoxicity, and ototoxicity were infrequent. Conclusions . Total cost of vancomycin treatment for 100 patients was $30,251: $23,855 for preparation and administration, $1710 for monitoring serum concentrations, and $4686 for treating adverse reactions. Drug costs accounted for only 55% of the total cost. Vancomycin is safe and effective, but phlebitis is underreported and significantly affects cost.  相似文献   
20.
Multiple prior administrations of donor-strain blood while under limited cyclosporine cover, consistently induce extensive rat renal allograft survival and transplantation tolerance. Yet it was hypothesized that some chronic rejection mechanisms were nevertheless operative since consistent but nonprogressive minor renal dysfunction was observed long-term. A histopathologic study on these putative tolerant rats was undertaken to test this hypothesis. Twenty long-term LEW recipients of BN renal allografts receiving the blood-CsA regimen were examined histopathologically at day 100 post-transplant. Sixteen control LEW recipients receiving only a BN renal allograft were studied acutely at day 7 posttransplant. The control recipients demonstrated a range of lesions consistent with previous studies on acute renal allograft rejection in the rat. However, tolerant recipients demonstrated mild-to-moderate lesions consistent with chronic mechanisms of rejection including the following: moderate focal interstitial mononuclear inflammatory cellular infiltration, with periglomerular and perivascular accumulation; occasional arteriolar luminal obliteration and glomerular atrophy; focal areas of moderate interstitial fibrosis; mild interstitial hemorrhage; mild-to-moderate tubular atrophy; and focal tubular necrosis. Previously our laboratory has documented that tissue-specific renal basement membrane antigens may be responsible for inciting this pattern of focal chronic interstitial inflammation. However, from the present histopathologic studies, it would appear likely that chronic rejection mechanisms in these recipients, which were defined as tolerant by immunologic criteria, involve both tissue-specific and MHC determinants. Therefore, induction of transplantation tolerance in these indefinite survivors is partial or incomplete.  相似文献   
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