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51.
OBJECTIVE: To evaluate the role of target temperature (28 degrees or 34 degrees C) in cardiac surgery on regional oxygenation during hypothermia and rewarming and systemic inflammatory response. DESIGN: Prospective, controlled, and randomized clinical study. SETTING: University hospital. PARTICIPANTS: Elderly patients (mean age 70 +/- 2 years) with acquired heart disease with an anticipated bypass time exceeding 120 minutes (n = 30). INTERVENTIONS: The patients were cooled to either 28 degrees C (n = 15) or 34 degrees C (n = 15). At hypothermia, bypass blood flow was reduced twice from full flow (2.4 L/min/m(2) body surface area [BSA]) to 2.0 L/min/m(2). MEASUREMENTS AND MAIN RESULTS: Hepatic and jugular venous oxygen tension and saturation were higher at 28 degrees C than at 34 degrees C. In comparison with the preoperative values, at 28 degrees C hepatic venous values were higher; whereas at 34 degrees C, they were lower. The reduction of pump blood flow during hypothermia, from 2.4 to 2.0 L/min/m(2)was accompanied by reductions of central, jugular, and hepatic oxygenation at both target temperatures. During rewarming, central and regional venous oxygenation decreased irrespective of the preceding temperature. The decrease was most pronounced in hepatic venous blood, with the lowest individual values <10%. Serum concentrations of C3a and IL-6 increased during hypothermia and increased further during rewarming irrespective of the preceding temperature. CONCLUSION: During cardiopulmonary bypass, hypothermia at 28 degrees C increases regional and central venous oxygenation better than at 34 degrees C. In contrast, venous oxygenation decreases during rewarming irrespective of the preceding temperature. No significant difference in the systemic inflammatory response associated with target temperature was detected.  相似文献   
52.
This article describes the outcome of 1,508 patients with traumatic brain injuries (TBI) treated in a single neurosurgical unit over an 8-year period. Our aim has been to compare those outcomes with our previous results and with other large patient series. Another important goal was to evaluate the effect of the introduction of a 4-year ongoing study initiated in January 1993 using a new strategy of prehospital care on postresuscitation Glasgow Coma Score (GCS) and Glasgow Outcome Score (GOS). Results from the 1,508 patients showed good recovery or moderate disability in 69%, severe disability or vegetative state in 11%, and a mortality rate of 20%. When outcome of the most severely injured patients (GCS < or = 8) was compared with those of our previous and other large international patient series, more favorable outcome figures were shown in the present study. To evaluate the impact of the improved prehospital care after half of the study period, a logistic regression analysis showed after January 1993 a significantly increased expected odds/ratio for a postresuscitation GCS 8-15 rather than a GCS 3-4 (odds/ratio: 2.2; p < 0.001). For patients with postresuscitation GCS 5-7 and 8-15, the expected odds/ratio for a GOS 4-5 instead of GOS 1 increased significantly (odds/ratio: 2.2 and 1.7, respectively; p < 0.05-0.01). For patients with GCS 3-4, an increased expected odds/ratio (2.0; p < 0.05) for a GOS 2-3 rather than a GOS 1 was seen. The principal conclusion is that outcome for the severely injured patients in the present study is more favorable than in other large series of TBI. We posit that the introduction of effective prehospital care most likely contributed to the improved postresuscitation neurological status and consequently to the better outcome observed after January 1993.  相似文献   
53.
BACKGROUND: Six men and seven women, aged 62 years, bedridden due to back pain from a septic spondylitis in the thoracolumbar region and not responding to conservative treatment, were operated on with transpedicular stabilisation of the affected segments to enhance mobilisation. All patients experienced immediately reduced back pain, allowing them to leave their bed and start mobilisation during the first postoperative day. At follow-up after a mean of 29 months (range 13-60 months) only one was using analgesics. RESULTS: Nine of the 11 patients with pathological neurology at surgery had improved, none had deteriorated, and all were ambulatory without bladder or bowel disturbances. Seven had achieved a solid interbody fusion, with a continued radiographic decrease in the spondylitic change in the rest, indicating that a progressive interbody fusion was in progress. Three individuals had increased kyphosis, a mean of 11 deg compared with the postoperative radiographs.  相似文献   
54.
This 2-year prospective controlled exercise intervention trial in 99 girls at Tanner stage 1, evaluating a school curriculum-based training program on a population-based level, showed that the annual gain in BMC, aBMD, and bone size was greater in the intervention group than in the controls. INTRODUCTION: Most exercise intervention studies in children, evaluating the accrual of BMD, include volunteers and use specifically designed osteogenic exercise programs. The aim of this study was to evaluate a 2-year general school-based exercise intervention program in a population-based cohort of girls at Tanner stage 1. MATERIALS AND METHODS: Forty-nine girls 7-9 years of age in grades 1 and 2 in one school were included in a school curriculum-based exercise intervention program of general physical activity for 40 minutes per school day (200 minutes/week). Fifty healthy age-matched girls in three neighboring schools, assigned to the general Swedish school curriculum of physical activity (60 minutes/week), served as controls. All girls were premenarchal, remaining in Tanner stage 1 during the study. BMC (g) and areal BMD (aBMD; g/cm2) were measured with DXA of the total body (TB), the lumbar spine (L2-L4 vertebrae), the third lumbar vertebra (L3), the femoral neck (FN), and the leg. Volumetric BMD (vBMD; g/cm3) and bone size were calculated at L3 and FN. Total lean body mass and total fat mass were estimated from the total body scan. Height and weight were also registered. Baseline measurements were performed before the intervention was initiated. Follow-up was done after 2 years. RESULTS: No differences between the groups were found at baseline in age, anthropometrics, or bone parameters. The annual gain in BMC was greater in the intervention group than in the controls: L2-L4, mean 3.8 percentage points (p = 0.007); L3 vertebra, mean 7.2 percentage points (p < 0.001); legs, mean 3.0 percentage points (p = 0.07). The intervention group had a greater annual gain in aBMD: total body, mean 0.6 percentage points (p = 0.006), L2-L4, mean 1.2 percentage points (p = 0.02), L3 vertebra, mean 1.6 percentage points (p = 0.006); legs, mean 1.2 percentage points (p = 0.007). There was also a greater mean annual gain in bone size in the L3 vertebra (mean 1.8 percentage points; p < 0.001) and in the FN (mean 0.3 percentage points; p = 0.02). CONCLUSIONS: A general school-based exercise program for 2 years for 7- to 9-year-old girls (baseline) enhances the accrual of BMC and BMD and increases bone size.  相似文献   
55.
A role for decorin in cutaneous wound healing and angiogenesis   总被引:2,自引:0,他引:2  
Decorin is known to influence tissue tensile strength and cellular phenotype. Therefore, decorin is likely to have an impact on tissue repair, including cutaneous wound healing. In this study, cutaneous healing of both excisional and incisional full‐thickness dermal wounds was studied in decorin‐deficient (Dcn?/?) animals. A statistically significant delay in excisional wound healing in the Dcn?/? mice occurred at 4 and 10 days postwounding and, in incisional wounds at 4, 10, and 18 days when compared with wild‐type (Dcn?/?) controls. Fibrovascular invasion into polyvinylalcohol sponges was significantly increased by day 18 in Dcn?/? mice relative to Dcn+/+ mice. The 18‐day sponge implants in the Dcn?/? mice showed a marked accumulation of biglycan when compared with the corresponding implants in Dcn+/+ mice. Thus, regulated production of decorin may serve as an excellent therapeutic approach for modifying impaired wound healing and harmful foreign body reactions.  相似文献   
56.
57.
OBJECTIVE: To investigate the geographical variation in prostate cancer incidence in Sweden, in particular the incidences of screening-detected tumours and curative treatment of prostate cancer. MATERIAL AND METHODS: Data were retrieved from the National Prostate Cancer Register of Sweden for all cases of prostate cancer diagnosed in the year 2000-01. There were a total of 14 376 cases of prostate cancer and the mean total annual age-adjusted incidence was 197/100 000 men. There were 3318 cases in tumour category T1c, i.e. non-palpable tumours diagnosed during work-up for an elevated serum level of prostate-specific antigen, 1006 of which (30%) were asymptomatic and detected at a health check-up. RESULTS: The difference between the counties with the lowest and highest age-adjusted incidences per 100 000 men of total prostate cancer was almost twofold (128 vs 217). The corresponding variation in incidence of category T1c tumours was more than fourfold (13 vs 60); the difference in incidence of T1c tumours detected in asymptomatic men was up to 10-fold (2 vs 20); and there was more than a fourfold variation in incidence of curative treatment between counties (13 vs 67). Measured incidences were mostly highest in urban regions and in counties with university hospitals. CONCLUSION: There are large geographical variations in prostate cancer incidence and in the frequency of curative treatment for prostate cancer in Sweden and there appear to be large geographical variations in the uptake of prostate cancer screening.  相似文献   
58.
New blood vessel formation in transplanted islets occurs within 7–14 days post-transplantation through both the expansion of donor islet endothelium and ingrowth of blood vessels from the implantation organ. However, several studies indicate that although the islets attract recipient blood vessels, the formed intra-islet vascular network is insufficient, which affects islet post-transplant function. This study aimed to develop an in vitro model to investigate the migration and proliferation properties of isolated liver and islet endothelium. Rat islet or liver endothelium was purified using Bandeiraea simplicifolia (BS-1)-coated Dynabeads. The liver endothelium displayed an increased migration and proliferation to islet-conditioned medium. These effects were fully prevented by adding a neutralizing vascular endothelial growth factor (VEGF)-antibody. In contrast, islet-produced VEGF failed to induce islet endothelial cell migration and only had marginal effects on islet endothelial cell proliferation. These properties could, however, be activated through blocking the effects of either endostatin, thrombospondin-1 or α1-antitrypsin. In conclusion, VEGF may attract recipient blood vessels towards intrahepatically transplanted islets, but intra-islet vascular expansion is hampered by angiostatic factors present within the islets and the islet endothelium. Inhibition of angiostatic factors early after transplantation may provide a strategy to restore the islet vascular network and improve islet graft function.  相似文献   
59.

Summary

The association between depression and loss of bone mineral density (BMD) has been reported inconsistently. This meta-analysis, which pooled results from 14 qualifying individual studies, found that depression was associated with a significantly decreased BMD, with a substantially greater BMD decrease in depressed women and in cases of clinical depression.

Introduction

The reported association between depression and loss of BMD has been controversial. This meta-analysis was conducted to determine whether depression and BMD are associated and to identify the variation in some subgroups.

Methods

English-language articles published before October 2008 were used as the data source. A total of six case-controlled and eight cross-sectional studies met prestated inclusion criteria (N?=?10,523). Information on study design, participant characteristics, measurements of BMD and depression, and control for potential confounders was abstracted independently by two investigators using a standardized protocol.

Results

Overall, depression was associated with a significant decrease in mean BMD of spine (?0.053 g/cm2 [95% confidence interval {CI} ?0.087 to ?0.018 g/cm2]) and hip (?0.052 g/cm2 [95% CI ?0.083 to ?0.022 g/cm2]). A substantially greater BMD decrease was observed in depressed women (?0.076 g/cm2 in spine; ?0.059 g/cm2 in hip) and in cases of clinical depression (?0.074 g/cm2 in spine; ?0.080 g/cm2 in hip).

Conclusion

Depression is associated with low BMD, with a substantially greater BMD decrease in depressed women and in cases of clinical depression. Depression should be considered as an important risk factor for osteoporosis.  相似文献   
60.
Gregg W. Stone, MD; James H. Ware, PhD; Michel E. Bertrand, MD; A. Michael Lincoff, MD; Jeffrey W. Moses, MD; E. Magnus Ohman, MD; Harvey D. White, MD; Frederick Feit, MD; Antonio Colombo, MD; Brent T. McLaurin, MD; David A. Cox, MD; Steven V. Manoukian, MD; Martin Fahy, MSc; Tim C. Clayton, MSc; Roxana Mehran, MD; Stuart J. Pocock, PhD; for the ACUITY Investigators

JAMA. 2007;298(21):2497-2506.

Context  At 30-day follow-up, patients with moderate- and high-risk acute coronary syndromes (ACS) undergoing early invasive treatment in the ACUITY trial with bivalirudin monotherapy vs heparin plus glycoprotein (GP) IIb/IIIa inhibitors had noninferior rates of adverse ischemic events with reduced rates of major bleeding. Deferred upstream use of GP IIb/IIIa inhibitors for selective administration to patients undergoing percutaneous coronary intervention (PCI) resulted in a significant reduction in major bleeding, although a small increase in composite ischemia could not be excluded.

Objective  To determine 1-year ischemic outcomes for patients in the ACUITY trial.

Design, Setting, and Patients  A prospective, randomized, open-label trial with 1-year clinical follow-up at 450 academic and community-based institutions in 17 countries. A total of 13 819 patients with moderate- and high-risk ACS undergoing invasive treatment were enrolled between August 23, 2003, and December 5, 2005.

Interventions  Patients were assigned to heparin plus GP IIb/IIIa inhibitors (n = 4603), bivalirudin plus GP IIb/IIIa inhibitors (n = 4604), or bivalirudin monotherapy (n = 4612). Of these patients, 4605 were assigned to routine upstream GP IIb/IIIa administration and 4602 were deferred to selective GP IIb/IIIa inhibitor administration.

Main Outcome Measure  Composite ischemia (death, myocardial infarction, or unplanned revascularization for ischemia) at 1 year.

Results  Composite ischemia at 1 year occurred in 15.4% of patients assigned to heparin plus GP IIb/IIIa inhibitors and 16.0% assigned to bivalirudin plus GP IIb/IIIa inhibitors (compared with heparin plus GP IIb/IIIa inhibitors, HR, 1.05; 95% CI, 0.95-1.16; P = .35), and 16.2% assigned to bivalirudin monotherapy (HR, 1.06; 95% CI, 0.95-1.17; P = .29). Mortality at 1 year occurred in an estimated 3.9% of patients assigned to heparin plus GP IIb/IIIa inhibitors, 3.9% assigned to bivalirudin plus GP IIb/IIIa inhibitors (HR, 0.99; 95% CI, 0.80-1.22; P = .92), and 3.8% assigned to bivalirudin monotherapy (HR, 0.96; 95% CI, 0.77-1.18; P = .67). Composite ischemia occurred in 16.3% of patients assigned to deferred use compared with 15.2% of patients assigned to upstream administration (HR, 1.08; 95% CI, 0.97-1.20; P = .15).

Conclusions  At 1 year, no statistically significant difference in rates of composite ischemia or mortality among patients with moderate- and high-risk ACS undergoing invasive treatment with the 3 therapies was found. There was no statistically significant difference in the rates of composite ischemia between patients receiving routine upstream administration of GP IIb/IIIa inhibitors vs deferring their use for patients undergoing PCI.

Trial Registration  clinicaltrials.gov Identifier: NCT00093158

  相似文献   

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