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91.
The quality of referrals of four general practitioners, two with high and two with average rates of referral to the department of internal medicine, was judged by an independent expert panel. The panel, consisting of two general practitioners and one specialist, reviewed a set of information about the referrals blindly and in random sequence. The same distribution of quality of referrals was found among the referrals of the two high referring general practitioners (n = 192) as among those of the general practitioners with average rates (n = 88); that is, 57% and 55% respectively, of the cases had clear medical indications for referral, while the data did not permit a conclusion in 15% and 10%, respectively, of the cases. Controlling for sex, age and status of the referral (first or repeat referral) did not alter the results. We conclude that using referral rates to judge referral quality is misleading. However, a blind and randomly performed panel review of referrals is a time consuming but feasible method of quality assessment.  相似文献   
92.
Five patients with McArdle's disease entered a double-blind, placebo-controlled, cross-over study of dantrolene sodium. None of the patients experienced beneficial effect of dantrolene sodium medication. Each patient performed 2 exercise tests. Surface EMG during exercise tests without medication showed a temporary increase in EMG activity during the adaptation phase. Quite unexpectedly however, in view of the negative clinical results, this electrophysiological manifestation of muscle fatigue during the adaptation phase diminished or disappeared in all patients investigated when dantrolene sodium was used.  相似文献   
93.
To achieve a disease-regulated transgene expression for physiologically responsive gene therapy of arthritis, a hybrid promoter was constructed. The human IL-1 beta enhancer region (-3690 to -2720) upstream of the human IL-6 promoter region (-163 to +12) was essential in mounting a robust response in HIG-82 synovial fibroblasts and in RAW 264,7 macrophages. A replication-deficient adenovirus was engineered with luciferase (Luc) controlled by the IL-1/IL-6 promoter (Ad5.IL-1/IL-6-Luc). LPS caused a 23- and 4.6-fold induction of Luc. activity in RAW cells infected with Ad5.IL-1/IL-6-Luc or the conventional Ad5.CMV-Luc construct, respectively. Next, adenoviruses (10(6) ffu) were injected into the knees of C57Bl/6 mice. An intra-articular injection of zymosan, 3 days after Ad5.IL-1/IL-6-Luc, increased Luc. activity by 39-fold but had no effect in the Ad5.CMV-Luc joints. The constitutive CMV promoter was rapidly silenced and could not be reactivated in vivo. In contrast, the IL-1/IL-6 promoter could be reactivated by Streptococcal cell wall (SCW)-induced arthritis up to 21 days after infection. Next the IL-1/IL-6 promoter was compared to the C3-Tat/HIV-LTR two-component system in wild-type, IL-6(-/-) and IL-1(-/-) gene knockout mice. Both systems responded well to LPS-, zymosan- and SCW-induced arthritis. However, the basal activity of the IL-1/IL-6 promoter was lower and IL-6 independent. This study showed that the IL-1/IL-6 promoter is feasible to achieve disease-regulated transgene expression for treatment of arthritis.  相似文献   
94.
BACKGROUND: Granulocyte-colony-stimulating factor (G-CSF) has been used in patients to increase the level of circulating hematopoietic progenitors. Although G-CSF has been administered to some healthy individuals, the kinetics of mobilization of peripheral blood stem cells (PBSCs), the optimum dose schedule and the incidence and nature of adverse reactions in normal individuals are not completely defined. STUDY DESIGN AND METHODS: Normal individuals (n = 102) who received G- CSF for 5 or 10 days at doses of 2, 5, 7.5, or 10 micrograms per kg per day were studied. The subjects were observed for symptoms and physical changes, and blood samples were obtained for a variety of laboratory tests. After 5 or 10 days of G-CSF treatment, PBSCs were collected by apheresis and analyzed. RESULTS: Overall, 89 percent of the individuals completed the 5-day treatment protocol and 88 percent completed the 10- day protocol without modification of the dose of G-CSF administered. Ninety percent of donors experienced some side effect of G-CSF. The most frequent effects noted were bone pain (83%), headache (39%), body aches (23%), fatigue (14%), and nausea and/or vomiting (12%). The dose of G-CSF administered directly affected the proportion of people with bone pain (p = 0.025) or body aches (p = 0.045) or who were feeling hot or having night sweats (p = 0.02) or taking analgesics (p = 0.01). With the 5-day dose schedule, several changes in serum chemistries occurred, including increases in alkaline phosphatase (p = 0.001), alanine aminotransferase (p = 0.0013), lactate dehydrogenase (p = 0.0001), and sodium (p = 0.0001). Decreases occurred in glucose (p = 0.045), potassium (p = 0.0004), bilirubin (p = 0.001), and blood urea nitrogen (p = 0.0017). In donors who received G-CSF for 5 days, the absolute neutrophil count was increased after one G-CSF dose, and it reached a maximum on Day 6, as did the number of CD34+ cells (64.6 +/? 55.9 × 10(6) cells/L). In those same donors, the platelet count after apheresis on Day 6 was 32 +/? 13 percent lower than pretreatment values (250 +/? 42 × 10(9) cells/L). In donors receiving G-CSF for 10 days, the neutrophil count reached a maximum on Day 8, but the number of CD34+ cells peaked on Day 6 (58.3 +/? 52.1 × 10(5) cells/L) and then declined. The platelet count decreased from pretreatment values by 28 +/? 12 percent prior to apheresis on Day 11. When individuals were treated for 5 days with G-CSF, the quantity of CD34+ cells collected was directly related to the G-CSF dose. When 5 micrograms per kg per day was given, 2.80 +/? 1.81 × 10(8) cells were collected, compared with collection of 4.67 +/? 3.11 × 10(8) cells when 10 micrograms per kg per day was given (p = 0.04). More important, PBSCs collected after 10 days of G-CSF administration (5 micrograms/kg/day) had significantly fewer CD34+ cells (0.82 +/? 0.37 × 10(8) cells, p = 0.01) than did PBSCs collected after 5 days of G-CSF (5 micrograms/kg/day). CONCLUSION: Most normal donors receiving G-CSF experience side effects, but these are mild to moderate in degree. Some alterations in blood chemistries occur, but none were clinically serious. Because of the symptoms associated with G-CSF, these individuals must be monitored closely. The treatment of normal donors with G-CSF for more than 5 days significantly decreased the number of circulating CD34+ cells and the quantity collected by apheresis.  相似文献   
95.

Background  

To gain insight into factors that might affect results of future case-control studies, we performed an analysis of children with sepsis and purpura admitted to the paediatric intensive care unit (PICU) of Erasmus MC-Sophia Children's Hospital (Rotterdam, The Netherlands).  相似文献   
96.
BACKGROUND: Testing for antibody to hepatitis B core antigen (anti-HBc) as a surrogate for hepatitis C viremia is no longer needed for blood donor screening. Currently, the important question is how much its use supplements hepatitis B surface antigen (HBsAg) donor screening in preventing transfusion-transmitted hepatitis B virus (HBV) infection. STUDY DESIGN AND METHODS: In a study conducted in the 1970s, 64 blood donors were associated with 15 cases of HBV (1.0%) in 1533 transfusion recipients. Sera from 61 donors at donation and 29 follow-up visits were available for present-day assays for HBsAg, HBV DNA, anti-HBc, and antibody to HBsAg (anti-HBs). RESULTS: HBsAg was found in four previously negative blood donors; HBV DNA was limited to three of these four. Anti-HBc was detected in six HBsAg-negative donors. Two other donors were negative in all assays at donation, but positive for anti- HBc and anti-HBs 2 to 4 months later. The remaining donors were negative for all HBV markers, which left five recipient cases unexplained. No HBV transmission was observed when anti-HBs sample-to- negative control values were > or = 10. CONCLUSION: Some 33 to 50 percent of cases of hepatitis B that could be transmitted by transfusion of blood from HBsAg-negative donors are prevented by anti- HBc screening. Anti-HBc-positive donors unequivocally positive for anti- HBs should be considered noninfectious for HBV and should be allowed to donate. Anti-HBc screening of paid plasmapheresis donors, supplemented by anti-HBs testing, would reduce the amount of HBV to be processed by virus inactivation and increase the content of anti-HBs in plasma pools.  相似文献   
97.
OBJECTIVES: To determine the variation in total daily energy expenditure (TDEE) and respiratory quotient (RQ) in mechanically ventilated children and examine the relation to daily and cumulative energy balance toward optimizing nutritional therapy. METHODS: Serial measurements of TDEE and RQ were performed in 18 patients (median age 16 months) with an indirect calorimeter during admission (total 69 TDEE measurements). Daily caloric intake was recorded, and after determination of the amount of carbohydrates and fat a RQ of these macronutrients (RQ(macr)) was obtained. Daily 24-h urine was analyzed for urinary nitrogen excretion. RESULTS: There was a great variability in the median serial TDEE between children (40-64 kcal/kg), while the variation within individual children was small; the mean intraindividual coefficient of variation (CV) in daily measurements of TDEE was less than 10% in 15 of the 18 children (83%). On the last day of measurement 8 children with a positive cumulative energy balance (+98 kcal/kg) had a significantly higher RQ than 10 with a negative cumulative energy balance (-24 kcal/kg, 0.89 vs. 0.84). From the difference between RQ and RQ(macr) the optimal caloric intake was determined as 1.4x TDEE, divided into 60% carbohydrates and 40% fat. From the median nitrogen excretion of 33 samples (300 mg/kg per day, range 60-708) optimal daily protein intake was calculated as 1.9 g/kg (range 0.4-4.4). CONCLUSIONS: For most children a single measurement of TDEE gave a good insight in the daily energy needs. RQ is strongly affected by the ratio energy intake/TDEE and by the cumulative energy balance. Optimal caloric intake was found to be 1.4x TDEE with a daily protein intake of 1.9 g/kg.  相似文献   
98.
BACKGROUND: Hepatitis virus(es) that are neither hepatitis B (HBV) nor hepatitis C (HCV) (non-B, non-C [NBNC]) may be transmitted by transfusion. The present study assessed donor values for alanine aminotransferase (ALT) and antibody to hepatitis B core antigen (anti- HBc) for their association with HCV and NBNC hepatitis outcomes among allogeneic blood recipients. STUDY DESIGN AND METHODS: Data on blood donors and recipients enrolled in the Transfusion- Transmitted Viruses Study in four United States cities from 1974 through 1980 were supplemented by anti-HBc testing of donors and anti-HCV evaluation of recipients. Two statistical approaches estimated the value of these indirect tests in detecting donors associated with HCV seroconversion and NBNC hepatitis in recipients. RESULTS: For HCV cases, donor ALT alone (at > or = 60 IU/L) had a sensitivity and a specificity of 30 and 96 percent, respectively, and anti-HBc alone (at > or = 60% inhibition) had a sensitivity and specificity of 53 and 86 percent, respectively. The two markers combined had a sensitivity and a specificity of 69 and 83 percent. For NBNC hepatitis cases, each measure had low sensitivity (20%) that was not improved by using both (28%) [corrected]. CONCLUSION: The indirect tests proved to be equal in sensitivity to the first-generation anti-HCV tests. The positive predictive power of these indirect tests in the 1980s was sufficient to affect HCV incidence in studies during that period. Improved anti-HCV assays, however, replaced the need for indirect tests. The sensitivity of indirect tests for NBNC hepatitis contributed little.  相似文献   
99.
The objective was to perform an economic evaluation comparing spinal cord stimulation (SCS) in combination with best medical treatment (BMT) with BMT in painful diabetic peripheral neuropathy patients. Alongside a prospective 2-center randomized controlled trial, involving 36 painful diabetic peripheral neuropathy patients with severe lower limb pain not responding to conventional therapy, an economic evaluation was performed. Incremental cost-effectiveness ratios were based on: 1) societal costs and quality-adjusted life years (QALYs), and 2) direct health care costs and the number of successfully treated patients, respectively, both with a time horizon of 12 months. Bootstrap and secondary analyses were performed to address uncertainty. Total societal cost amounted to €26,539.18 versus €5,313.45 per patient in the SCS and BMT group, respectively. QALYs were .58 versus .36 and the number of successfully treated patients was 55% versus 7% for the SCS and BMT group, respectively. This resulted in incremental cost-effectiveness ratios of €94,159.56 per QALY and €34,518.85 per successfully treated patient, respectively. Bootstrap analyses showed that the probability of SCS being cost-effective ranges from 0 to 46% with willingness to pay threshold values ranging between €20,000 and €80,000 for a QALY. Secondary analyses showed that cost-effectiveness of SCS became more favorable after correcting for baseline cost imbalance between the 2 groups, extending the depreciation period of SCS material to 4 years, and extrapolation of the data up to 4 years. Although SCS was considerably more effective compared with BMT, the substantial initial investment that is required resulted in SCS not being cost-effective in the short term. Cost-effectiveness results were sensitive to baseline cost imbalances between the groups and the depreciation period of the SCS material.

Perspective

Painful diabetic peripheral neuropathy is a common complication of diabetes mellitus and the humanistic and economic burden is high. This article presents the cost-effectiveness of SCS in patients suffering from painful diabetic peripheral neuropathy from a societal and health care perspective with a time horizon of 12 months.  相似文献   
100.

OBJECTIVES:

To evaluate vascular protection treatment patterns and attainment of the 2003 Canadian Diabetes Association’s recommended targets in ambulatory patients with type 2 diabetes.

METHODS:

Between 2005 and 2006, 3002 outpatients with type 2 diabetes were enrolled by 229 primary health care settings across Canada. Baseline characteristics, therapeutic regimens and treatment success – defined as the achievement of a blood pressure (BP) of 130/80 mmHg or lower, glycosylated hemoglobin (A1C) of 7% or lower, low-density lipoprotein cholesterol (LDL-C) lower than 2.5 mmol/L and total cholesterol/high-density lipoprotein cholesterol ratio lower than 4.0 – are reported.

RESULTS:

Overall, 46% of individuals had a BP that was above the Canadian Diabetes Association’s recommended target. Of these, 11% were untreated, 28% were receiving monotherapy, 38% were not receiving an angiotensin-converting enzyme inhibitor and 16% were not receiving either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Optimal A1C levels were achieved in 53% of patients. Of those who did not attain A1C targets, 3% were not on glucose-lowering pharmacotherapy and 27% were receiving monotherapy. A total of 74% of patients were treated with statins. Overall, 64% and 62%, respectively, met the target LDL-C and the target total cholesterol/high-density lipoprotein cholesterol ratio. Statins were not prescribed to 43% of patients with LDL-C above target. Antiplatelet therapy was implemented in 81% of patients. In total, 21% achieved the combined targets for BP, A1C and LDL-C.

INTERPRETATION:

A substantial proportion of patients did not achieve guideline-recommended targets and were not receiving evidence-based therapy for vascular protection two years after publication of the Canadian guidelines. More research is warranted, and novel and effective strategies must be tested and implemented to correct this ongoing treatment gap.  相似文献   
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