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971.
Obesity-related hepatic steatosis is a major risk factor for metabolic and cardiovascular disease. Fat reduced hypocaloric diets are able to relieve the liver from ectopically stored lipids. We hypothesized that the widely used low carbohydrate hypocaloric diets are similarly effective in this regard. A total of 170 overweight and obese, otherwise healthy subjects were randomized to either reduced carbohydrate (n = 84) or reduced fat (n = 86), total energy restricted diet (-30% of energy intake before diet) for 6 months. Body composition was estimated by bioimpedance analyses and abdominal fat distribution by magnetic resonance tomography. Subjects were also submitted to fat spectroscopy of liver and oral glucose tolerance testing. In all, 102 subjects completed the diet intervention with measurements of intrahepatic lipid content. Both hypocaloric diets decreased body weight, total body fat, visceral fat, and intrahepatic lipid content. Subjects with high baseline intrahepatic lipids (>5.56%) lost ≈7-fold more intrahepatic lipids compared with those with low baseline values (<5.56%) irrespective of diet composition. In contrast, changes in visceral fat mass and insulin sensitivity were similar between subgroups, with low and high baseline intrahepatic lipids. CONCLUSION: A prolonged hypocaloric diet low in carbohydrates and high in fat has the same beneficial effects on intrahepatic lipid accumulation as the traditional low-fat hypocaloric diet. The decrease in intrahepatic lipids appears to be independent of visceral fat loss and is not tightly coupled with changes in whole body insulin sensitivity during 6 months of an energy restricted diet.  相似文献   
972.
Autotransplantation is considered a standard procedure with a poorer prognosis for mature than for immature teeth. In this case report, the root tip of an almost fully developed tooth was resected during autotransplantation to fit into a deficient recipient site. As a positive side effect, the apical foramen was enlarged, with potential improvement of the probability of revascularization. Clinical and radiologic follow-up examinations up to 18 months indicated revascularization and uneventful periodontal regeneration and thus successful autotransplantation. This case supports the hypothesis that intraoperative apicoectomy can improve the prognosis for revascularization of mature autotransplanted teeth. Further prospective controlled clinical studies are needed to confirm this innovative surgical approach.  相似文献   
973.
Background: Patients with acute low back pain may require emergency transport because of pain and immobilization. Transcutaneous electrical nerve stimulation (TENS) is a nonpharmaceutical therapy for patients with low back pain. Objective: To evaluate the efficacy of paramedic‐administered TENS in patients with acute low back pain during emergency transport. Methods: This was a prospective, randomized study involving 74 patients transported to hospital. The patients were randomly assigned to two groups: group 1 (n= 36) was treated with true TENS, while group 2 (n= 36) was treated with sham TENS. The authors recorded pain and anxiety as the main outcome variables using a visual analog scale (VAS). Results: The authors recorded a significant (p < 0.01) pain reduction (mean ± standard deviation) during transport in group 1 (79.2 ± 6.5 mm VAS to 48.9 ± 8.2 mm VAS), whereas pain scores remained unchanged in group 2 (75.9 ± 16.4 mm VAS and 77.1 ± 11.2 mm VAS). Similarly, the scores for anxiety were significantly reduced (p < 0.01) in group 1 (81.7 ± 7.9 mm VAS to 69.2 ± 12.1 mm VAS) after treatment. No significant change was noted (84.5 ± 5.8 mm VAS and 83.5 ± 8.9 mm VAS, respectively) in group 2. Conclusions: TENS was found to be effective and rapid in reducing pain during emergency transport of patients with acute low back pain and should be considered due to its ease of use and lack of side effects in the study population.  相似文献   
974.
BACKGROUND: In the Netherlands, 500,000 blood donors are active. Blood of all donors is currently typed serologically for ABO, the Rh phenotype, and K. Only a subset of donors is typed twice for a larger set of red cell (RBC) and/or platelet (PLT) antigens. To increase the direct availability of typed RBCs and PLTs, a high-throughput technique is being developed to genotype the whole donor cohort for all clinically relevant RBC and PLT antigens. STUDY DESIGN AND METHODS: A multiplex polymerase chain reaction was developed to both amplify and fluorescently label 19 gene fragments of RBC and PLT antigens in one reaction. To test the setup of the genotyping method by microarray, a pilot study with human PLT antigen (HPA)-typed donor samples was performed. On each slide, 12 arrays are present containing 20 probes per PLT antigen system (28 for HPA-3). The allele-specific oligohybridization method was used to discriminate between two different alleles. RESULTS: Two blinded panels encompassing 94 donors were genotyped for HPA-1 through -5 and -15; no discrepancies were found compared to their serologic typing (HPA-1, -2, -3, -4, and -5) and genotyping (HPA-15; TaqMan, Applied Biosystems). CONCLUSION: This study shows that the HPA microarray provides a reliable and fast genotyping procedure. With further development an automated throughput for complete typing of large donor cohorts can be obtained.  相似文献   
975.
BACKGROUND: Nucleic acid testing (NAT) of pooled plasma samples from individual blood donations for viral nucleic acids has become widely established. Full automation of such sample processing can overcome many of the problems associated with methods used so far. STUDY DESIGN AND METHODS: In this study an automated extraction method for viral nucleic acids (parvovirus [PAV] B19 DNA, hepatitis B virus [HBV] DNA, and hepatitis A virus [HAV] RNA), starting directly from the minipool sample (n = 96, 9.6 mL), was evaluated. A magnetic separation module I (chemagic, Polymer Laboratories) in combination with the chemagic viral DNA and RNA kit special based on the use of magnetic beads was used for this purpose. More than 144 pools spiked with defined concentrations of reference material and an additional 102 pools negative for the analyte were extracted and amplified. The isolated viral nucleic acids were detected by polymerase chain reaction (PCR). RESULTS: The assays were highly specific and obtained a 95 percent detection limit of 875 IU per mL of pooled single donation for PAV B19, 260 IU per mL for HAV, and 1274 IU per mL for HBV, respectively. The crossing points showed variation coefficients from 1.49 to 2.76 percent. The turnaround time for the whole process was 3 hours. Testing of subpools to determine an infected single donation would be possible with the same general extraction method. A total of 102 unspiked minipools (96 x 100 microL per donation) were analyzed and none tested positive. CONCLUSION: The automated magnetic bead-based extraction in combination with real-time PCR detection can be used to routinely screen blood donations for viremic donors to further increase the safety of blood products. Minipools as well as subpools can be directly processed.  相似文献   
976.
Right-sided endocarditis usually involves the tricuspid valve, predominantly in intravenous drug abusers, in patients with anti-arrhythmic devices or central venous lines, and in patients with skin or genitourinary infection and with congenital heart disease 1. We describe a case of a 15-y-old patient, who had tricuspid valve endocarditis in a morphologically normal valve after having his ear pierced, without history of parenteral drug addiction and vascular catheter use. Progression of vegetation size and development of tricuspid valve regurgitation in spite of the intensive antibiotic treatment eventually required surgical intervention.  相似文献   
977.
Patients with imported highly contagious diseases like viral hemorrhagic fever (VHF), pneumonic plague or anthrax require special preventive measures and strict isolation. In addition, new emerging infections like severe acute respiratory syndrome (SARS) and epidemic influenza also have to be taken into account. At present five high security infectious disease units for patient care are available in Germany. Due to the relatively nonspecific symptoms, a patient with one of these infections may also be admitted to any other hospital. Therefore each hospital should develop a concept for the management and control of these lifethreatening highly contagious diseases. The present article describes the current emergency plan developed for the management of patients with highly contagious diseases at Hannover Medical School.  相似文献   
978.

OBJECTIVE

To determine whether pharmacological treatment of depression in low-income minorities with diabetes improves A1C and quality of life (QOL).

RESEARCH DESIGN AND METHODS

This was a 6-month, randomized, double-blind, placebo-controlled trial. Patients were screened for depression using Whooley''s two-question tool at a county diabetes clinic. Depression was confirmed (or not) with the Computerized Diagnostic Interview Survey (CDIS) software program, and the severity of depression was assessed monthly by the Hamilton Depression Scale (HAM-D). Depressed subjects with A1C levels ≥8.0% were randomly assigned to receive either sertraline or placebo. Diabetes care was provided by nurses following detailed treatment algorithms who were unaware of therapy for depression.

RESULTS

A total of 150 subjects answered positively to at least one question on Whooley''s questionnaire. The positive predictive value for depression diagnosed by CDIS was 69, 67, and 84% for positive answers to question 1 only, question 2 only, or both, respectively. Of the 89 subjects who entered the study, 75 completed. An intention-to-treat analysis revealed significant differences between baseline and 6 months in HAM-D and pain scores, QOL, and A1C and systolic blood pressure levels in both groups, with no differences between groups for the first three but a significantly greater decrease with sertraline in A1C and systolic blood pressure levels. Changes in HAM-D scores and A1C levels were significantly correlated in all subjects (P = 0.45 [P < 10−6]).

CONCLUSIONS

In this low-income minority population, pharmacological treatment of depression significantly improved A1C and systolic blood pressure levels compared with placebo.The prevalence of depression among people with diabetes is more than twice that of the general population (1). Coexistence of depression in persons with diabetes is associated with worse glycemic control (2), which may be due to less adherence to self-care behaviors and medications (3). Eventually, there is increased morbidity (4) and mortality (5) and higher medical costs (6).The prevalence of untreated depression in people with diabetes is higher in minorities (1). Yet, screening for and treating depression are less common in this population (7). Very little research has been published on diabetes and depression with a focus on minority populations, who have significant disparities in outcomes (8), such as higher A1C levels (9), increased rates of complications (10), and more severe depression (8).Depression is associated with worse glycemic control (2). Some studies have evaluated whether treatment of depression will improve A1C levels (1120). However, these drug studies were open label, were of short duration, and/or were conducted in highly educated (more than high school education) Caucasian populations. Most showed that although depression was improved, A1C levels were not. We sought to determine whether use of antidepressants in a minority population with uncontrolled diabetes improved their A1C levels, quality of life (QOL), and depression compared with placebo.  相似文献   
979.
By injecting a few cubic centimeters of saline into the coronary artery and using thermodilution principles, mean transit time (T(mn)) of the injectate can be calculated and is inversely proportional to coronary blood flow. Because microvascular resistance equals distal coronary pressure (P(d)) divided by myocardial flow, the product P(d). T(mn) provides an index of myocardial resistance (IMR). In this in vitro study in a physiologic model of the coronary circulation, we compared IMR to true myocardial resistance (TMR) at different degrees of myocardial resistance and at different degrees of epicardial stenosis. Absolute blood flow was varied from 42 to 203 ml/min and TMR varied from 0.39 to 1.63 dynes. sec/cm(5). Inverse mean transit time correlated well to absolute blood flow (R(2) = 0.93). Furthermore, an excellent correlation was found between IMR and TMR (R(2) = 0.94). IMR was independent on the severity of epicardial stenosis and thus specific for myocardial resistance. Thus, using one single guidewire, both fractional flow reserve and IMR can be measured simultaneously as indexes of epicardial and microvascular disease, respectively, enabling separate assessment of both coronary arterial and microvascular disease.  相似文献   
980.
Abstract Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a major cause of sudden cardiac death and ventricular tachyarrhythmias in young, apparently healthy individuals and athletes. Myocardial atrophy with subsequent fibrofatty replacement predominantly affects right ventricular myocardium and results in global and regional dysfunction as well as areas of slow conduction and dispersion of refractoriness which are prerequisites for reentrant ventricular tachyarrhythmias.Patients affected with ARVC should be excluded from competitive sports and vigorous training. To provide optimal treatment, a detailed diagnostic evaluation and risk stratification are mandatory. Tailored treatment strategies aim at the suppression or effective termination of recurrent ventricular tachyarrhythmias and prevention of sudden death by antiarrhythmic drug therapy, catheter ablation, or implantation of a cardioverter defibrillator (ICD).Antiarrhythmic drugs may be used as a stand-alone treatment to suppress ventricular tachycardia (VT) recurrences in patients with ARVC and low risk of sudden death. Sotalol (preferred) or amiodarone in combination with -blockers showed the highest efficacy rates. In patients at higher risk, an ICD should be implanted and antiarrhythmic drugs be used only as an adjunct to prevent or suppress frequent VT recurrences and ICD discharges.Catheter ablation using conventional or electroanatomic mapping techniques yields good acute results for eliminating the targeted arrhythmia substrate. However, during the progressive long-term course of ARVC, VT recurrences from new arrhythmia foci are frequent and therefore limit the curative value of catheter ablation. In patients with frequent VT recurrences and ICD discharges, however, catheter ablation plays an important role as a palliative and adjunctive treatment option for arrhythmia suppression.ICD therapy has been increasingly used for secondary and also primary prevention of sudden death in patients with ARVC. In secondary prevention, the ICD has shown to improve the long-term prognosis of patients at high risk of sudden death by effective termination of life-threatening recurrences of ventricular tachyarrhythmias. However, adequate lead placement may be difficult and lead-related complications during long-term follow-up must be taken into account. The role of ICD therapy for primary prevention of sudden death in ARVC is not yet adequately defined.Ongoing international registries will provide important additional data to improve risk stratification and refine treatment algorithms in order to select the best individual treatment for arrhythmia suppression and prevention of sudden death in patients with ARVC.  相似文献   
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