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71.
To evaluate the effects of grape polyphenols on plasma lipids, inflammatory cytokines, and oxidative stress, 24 pre- and 20 postmenopausal women were randomly assigned to consume 36 g of a lyophilized grape powder (LGP) or a placebo for 4 wk. The LGP consisted of 92% carbohydrate and was rich in flavans, anthocyanins, quercetin, myricetin, kaempferol, and resveratrol. After a 3-wk washout period, subjects were assigned to the alternate treatment for an additional 4 wk. The placebo consisted of an equal ratio of fructose and dextrose and was similar in appearance and energy content (554 kJ) to LGP. Plasma triglyceride concentrations were reduced by 15 and 6% in pre- and postmenopausal women, respectively (P < 0.01) after LGP supplementation. In addition, plasma LDL cholesterol and apolipoproteins B and E were lower due to LGP treatment (P < 0.05). Further, cholesterol ester transfer protein activity was decreased by approximately 15% with intake of LGP (P < 0.05). In contrast to these beneficial effects on plasma lipids, LDL oxidation was not modified by LGP treatment. However, whole-body oxidative stress as measured by urinary F(2)-isoprostanes was significantly reduced after LGP supplementation. LGP also decreased the levels of plasma tumor necrosis factor-alpha, which plays a major role in the inflammation process. Through alterations in lipoprotein metabolism, oxidative stress, and inflammatory markers, LGP intake beneficially affected key risk factors for coronary heart disease in both pre- and postmenopausal women.  相似文献   
72.
A prospective, randomized, controlled, multi-centre clinical trial was performed to test the effectiveness of an antimicrobial central venous catheter (CVC) made of polyurethane integrated with silver, platinum and carbon black (Vantex). Adults expected to require a CVC for more than 60 h were eligible, and were randomized to receive the test or control catheter. All CVCs were inserted with new venipunctures using full aseptic technique. Following catheter removal, the distal tip and an intracutaneous segment were removed and cultured using semiquantitative and quantitative methods. Peripheral blood samples were obtained and cultured to confirm cases of catheter-related bloodstream infection (CRBSI). Bacterial and fungal organisms were identified by standard microbiological methods. Catheter placement was performed primarily in the intensive care unit (50%) or operating theatre (42%). Complete data could be evaluated for 539 patients (77%). The mean duration of CVC placement was 149.3h (six days). There were no significant differences in colonization or bacteraemia rates between the test and control catheters. The overall colonization rate was not particularly low (24.5%), and yet CVC-related bacteraemia occurred in only 1.4% of patients, and CRBSI occurred in only one patient from the control group (0.2%). Insertion site and dressing change frequency were significantly associated with the colonization rate. Although CVCs with antimicrobial features have been associated with a decrease in catheter-related colonization and bacteraemia, this study demonstrated that infection rates may depend more on non-catheter-related factors, such as adherence to infection control standards, selection of insertion site, duration of CVC placement, and dressing change frequency. As microbial resistance increases, clinicians should make maximal use of these processes to reduce catheter-related infections.  相似文献   
73.
The germinal center (GC) is an important anatomical site for the development of high affinity antibodies during T-cell dependent B cell responses. Although the importance of the GC response to humoral immunity is well known, much remains to be elucidated about GC induction, maintenance and regulation. Recent studies examining the GC response in mice have identified key molecules expressed on follicular dendritic cells that support the differentiation of GC B cells, revealed essential chemokines that direct the organization of light and dark zones, and demonstrated potentially novel roles for TNF family members in the differentiation of GC B cells.  相似文献   
74.
BACKGROUND: Chronic hepatitis C is often a mild disease in children, but whether this is related to younger age or shorter duration of infection is unclear. Histologic severity has been shown to correlate with duration of infection regardless of age. OBJECTIVES: We compared histologic findings in children and adults with chronic hepatitis C while controlling for sex, duration of infection, hepatitis C virus (HCV)-RNA level, and genotype. METHODS: Twenty-one children and 52 adults whose infection was less than 20 years in duration and who had undergone a liver biopsy were included. Two blinded liver pathologists reviewed the liver biopsies and scored inflammatory activity and fibrosis using the modified Knodell scoring system. RESULTS: The groups were the same with respect to HCV-RNA level (P=0.8), and genotype (P=0.6) but differed in duration of disease (P=0.01) and sex composition (P=0.005). Covariate analysis showed no influence of genotype, duration of infection, or HCV-RNA level on outcome. In controlling for sex, children had significantly milder liver disease and alanine aminotransferase (ALT) elevations. CONCLUSIONS: With equal duration of infection, HCV-RNA level, and genotype, children have lower serum ALT levels and less severe liver disease than adults infected with HCV.  相似文献   
75.
In lieu of traditional training of examiners to identify cerebral palsy on a neurologic examination at age 1 year, we proposed an alternative approach using a multimedia training video and CD-ROM we developed after a two-step validation process. We hypothesized that use of CD-ROM interactive training will lead to reliable and valid performance of the neurologic examination by both pediatric neurologists and nonpediatric neurologists. All examiners were asked to take one of six interobserver variability tests found on the CD-ROM on two occasions. In the first interobserver variability evaluation, 89% (531 of 594) of the responses agreed with the gold standard responses. Following annotated feedback to the examiners about the two items that had a 60% correct rate, the correct response rate rose to 93% (114 of 123). In the second interobserver variability evaluation, 88% (493 of 560) of the responses agreed with the gold standard responses. Following annotated feedback to the examiners about the four items that had a 70% correct rate, the correct response rate rose to 96% (104 of 108). Interactive CD-ROM examination training is an efficient and cost-effective means of training both neurologists and non-neurologists to perform structured neurologic examinations in 1-year-old children. It provides an effective means to evaluate interobserver variability, offers a route for feedback, and creates an opportunity to reevaluate variability, both immediately and at periodic intervals.  相似文献   
76.
Cranial suture simulator for ultrasound diagnosis of craniosynostosis   总被引:1,自引:0,他引:1  
Background: In evaluating the effectiveness of ultrasound as a screening tool for craniosynostosis it was discovered that sonologists and sonographers needed more experience scanning and visualizing cranial sutures on ultrasound. Objective: To create an ultrasound simulator to train radiologists and technologists to locate and recognize patent and fused cranial sutures in children. Materials and methods: The hypoechoic appearance of patent sutures was simulated by cutting lines into life-sized plastic doll heads and filling them with a commercial hypoechogenic material. Fused hyperechoic sutures were simulated by not cutting into the hard plastic region of a suture. The simulators teaching value was evaluated on three radiology residents and three fellows. Subjects performed pre-training scans on unknown simulators, received feedback and an opportunity to scan a training simulator, and then performed post-training scans on random unknown simulators. Accuracy was recorded as percentage of correctly demonstrated sutures. Results: The suture simulator reproduces the sonographic appearance of patent and fused cranial sutures. Accuracy of acquisition, interpretation, and overall diagnosis increased from 64 to 91%, 79 to 91%, 61 to 97%, respectively, between pre and post training scans. Conclusion: An ultrasound simulator can reproduce the appearance of patent and fused cranial sutures in children and can be used to train radiologists and technologists in the performance of a screening protocol.  相似文献   
77.
Nearly 50,000 new cases of primary hyperparathyroidism (PHPT) are diagnosed annually in the United States. Most information about the disease focuses on the white population. We evaluated African American (AA) and white patients at our tertiary care university medical center to determine whether there was a racial difference in presentation of PHPT. A retrospective chart review of patients treated surgically for PHPT between 1997 and 2002 was performed. Demographic data, laboratory values, objective symptoms, surgical procedure, and histologic findings were recorded. The AA participants were matched to whites by age and gender. The effect of race was adjusted for the matching variables by including them in regression models. ANOVA chi2 tests were performed on the race effects. Thirty-six (14.4%) of the 286 patients treated for PHPT at Wake Forest University Baptist Medical Center during this 5-year period were AA. There was no difference in serum calcium or presence of objective symptoms, but PTH levels were significantly higher for blacks (207.5 vs 143.5 pg/mL; P = 0.02). In our study, AA patients had significantly higher parathyroid hormone levels at time of surgical intervention but did not present with a difference in symptoms or more advanced disease. Further research is recommended to characterize ethnic differences in patients with PHPT.  相似文献   
78.
The use of intercalary allografts has been an important innovation for use in limb-salvage surgery. However, the principal disadvantage of intercalary allografts is a high incidence of nonunion, fracture, and infection. With a recent trend toward higher doses of chemotherapy, an increased incidence of nonunion and healing problems can be anticipated with the use of allografts. In this article, the authors report two cases in which a vascularized fibula bone flap was used with an intercalary allograft, utilising an intramedullary approach, for immediate femur reconstruction following sarcoma resection. The rationale for this approach is to combine the mechanical strength of an allograft with the biologic activity of a vascularized bone flap. The allograft provides bone stock and early stability, while the addition of the vascularized bone flap substantially facilitates the host-allograft union.  相似文献   
79.
Catheterization is considered to be a mandatory procedure for adequate bladder drainage following an anti-incontinence operation until the recovery of normal voiding function occurs. We conducted this prospective study to challenge this practice. A total of 86 patients with genuine stress incontinence who underwent a modified Burch coplosuspension were randomized into two groups based on the day of operation. The study group consisted of 42 patients who had the transurethral Foley catheter removed postoperatively the next morning (Group A). The control group was composed of 43 patients who had the transurethral indwelling catheter left in place until the fifth postoperative day (Group B). The percentages of immediate voiding difficulties in Groups A and B were 7.1% and 0%, respectively (P >0.05). The postoperative urinary tract infection rates of Groups A and B were 16.6% and 23.3%, respectively (P >0.05). The success rates of our patients were not compromised after our modified operative procedures (78.6% with dry results and 19.0% with improved symptoms in Group A vs. 74.4% with dry results and 20.9% with improved symptoms in Group B, P >0.05). Our results imply that it is not necessary that an indwelling catheter, for bladder drainage, be left in place until the fifth postoperative day to prevent immediate voiding difficulties. Editorial Comment: The authors have performed a prospective randomized clinical trial of two different bladder management schemes involving a urethral catheter following a modified Burch colposuspension. Group A began their voiding trial on Day 1, Group B began their voiding trial on Day 5 after a 2-day clamped catheter bladder training program. Patients were not discharged until they had normal residuals (<100 ml). There were low, not statistically different, rates of immediate voiding difficulty in either group (7.1% vs. 0%) and therefore the only significant difference between the two groups was the length of hospitalization (5.3 days for Group A and 7.4 days for Group B). They conclude that it is not necessary for a urethral catheter to be left in for 5 days. Very few urogynecologists would disagree with this conclusion. The authors should be commended for performing a prospective randomized study of voiding trials. However, the relevance of this study to clinical practice is extremely limited since most urogynecologists do not perform urethral catheter clamping bladder training programs, nor wait 5 days to start a voiding trial  相似文献   
80.
IL-12 and IFN-gamma play key roles in murine lupus and planted antigen models of glomerulonephritis. However, their roles in renal organ-specific autoimmunity are unknown. To establish the roles of endogenous IFN-gamma and IL-12 in experimental autoimmune anti-glomerular basement membrane (GBM) glomerulonephritis (EAG), EAG was induced in normal C57BL/6 mice (WT), IL-12p40-deficient (IL-12p40-/-) mice, and IFN-gamma-deficient (IFN-gamma-/-) mice by immunization with alpha3-alpha5(IV)NC1 heterodimers. At 13 wk, WT mice developed EAG with linear mouse anti-GBM antibody deposition, histologic injury, proteinuria, and mild tubulointerstitial disease. Compared with WT mice, IL-12p40-/- mice had decreased histologic injury and trends to decreased leukocyte infiltrates. In contrast, 40% (4 of 10) of IFN-gamma-/- mice developed significant crescent formation and focal or diffuse interstitial infiltrates (WT, 0 of 8). Compared with WT and/or IL-12p40-/- mice, IFN-gamma-/- mice developed increased injury: histologic injury, total glomerular cell numbers, leukocytes in glomeruli, and renal expression of P-selectin and intercellular adhesion molecule 1. All groups developed similar serum anti-alpha3-alpha5(IV)NC1 antibodies and glomerular Ig deposition, but IFN-gamma-/- mice had decreased anti-alpha3-alpha5(IV)NC1 IgG2a. Therefore, IFN-gamma-/- mice developed increased cellular reactants despite a potentially less damaging antibody response. Dermal delayed-type hypersensitivity was increased in alpha3-alpha5(IV)NC1 immunized IFN-gamma-/- mice and was suppressed by recombinant murine IFN-gamma. CD4+ cells from draining nodes of immunized IFN-gamma-/- mice showed increased proportions of proliferating CD4+ cells but similar numbers of apoptotic cells. These studies demonstrate that in renal organ-specific autoimmunity, IL-12 is pathogenetic but IFN-gamma is protective. They lend weight to the hypothesis that depending on the context/severity of the nephritogenic immune response IFN-gamma has different effects.  相似文献   
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