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1.
The synthesis of d-and l-(1-11C)tyrosine, starting with 11C-cyanide, is reported. dl-(1-11C)Tyrosine was prepared by the Bücherer-Strecker reaction, from carrier added 11C-cyanide with an incorporation of 80% in 20 min. The isolation of the pure d- and l-amino acid isomers from the enantiomeric mixture was accomplished within 15 min by preparative HPLC using a chiral stationary phase and a phosphate buffer as the mobile phase. Typically, the total synthesis time was 50 min (including purification) from end of trapping of 11C-cyanide, with a radiochemical yield of d- and l-amino acid of 40%–60%. The d- and l-(1-11C)tyrosine were both obtained optically pure, with a carrier added specific activity of 0.3–0.5 Ci/mmol and a radiochemical purity better than 99%. The 11C labelled l-tyrosine was used in an in vivo study in the human brain using positron emission tomography (PET).  相似文献   
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Our objectives were to translate the Quality of Life Scale (QOLS) into German and to evaluate its reliability and validity for the use in patients with fibromyalgia (FMS). Together with German versions of the Fibromyalgia Impact Questionnaire (FIQ), the SF-36, a tender point count (TPC) and other questionnaires, we administered the QOLS to 146 patients with FMS. Patients were asked about the severity of pain today (VAS) and the duration of symptoms. Test-retest reliability was assessed using Spearman's correlations. Internal consistency was evaluated with Cronbach's alpha. Construct validity of the QOLS was evaluated by correlating the QOLS with the FIQ, the SF-36, the Beck Depression Inventory (BDI), and the Symptom Checklist (SCL-90-R) as well as with the pain variables. An exploratory factor analysis (EFA) was also conducted. Mean age was 53.1?years. Means were for pain today 6.8 and for duration of symptoms 11.8?years. Test-retest reliability for the total QOLS was rho?=?.91. Internal consistency was α?=?.90. Low-to-moderate correlations were obtained between the QOLS and the total FIQ (rho?=?-.42**), the SF-36 (e.g. physical functioning rho?=?.37**; mental health rho?=?.56**) as well as the pain variables (VAS rho?=?-.11?ns; TPC rho?=?-.20*). Psychological variables were moderately to substantially correlated with the QOLS (e.g. BDI rho?=?-.61**). An EFA suggested a three-factor solution. The QOLS-G is a reliable and valid instrument for measuring quality of life in German patients with FMS.  相似文献   
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This case-study (n=41,969) of voluntary switching among Mecklenburg County, North Carolina Medicaid managed care plans showed a low switching rate of 14.5 per 100 member-years over 33 months, or 5.3 averaged annually. Population, plan and plan characteristics, claims and telephone survey data were examined to better understand this important behavioral measure. Switching in Medicaid managed care, which is little studied, is contrasted with the extensive literature on middle class switching. Policy implications included the suitability of Medicaid populations for managed care and the need for more research on switching and disenrollment and the Medicaid innovation of neutral health benefits advising.  相似文献   
5.
This article presents findings of a 1998-99 resurvey of Medicaid recipients (adults and children) who were first surveyed in 1996 in Mecklenburg and New Hanover Counties in North Carolina. It reports the insurance status and health care of former Medicaid recipients and compares them with those still on Medicaid in 1998-99 in respect to access to care and satisfaction. Just under half of those who had left Medicaid were without employer-sponsored health insurance (ESI) at the time of the second survey. Former Medicaid recipients without ESI rated their access to healthcare lower than those with Medicaid and former Medicaid recipients with ESI. Over 50% of target respondents in all groups were more positive than negative on access-related variables. But only those on Medicaid in Mecklenburg County had significant increases in satisfaction with health care between 1996 and 1998-99. Those in the control county who were off Medicaid and those still receiving it and former recipients in Mecklenburg showed no significant change. The study has great policy relevance in light of recent national welfare reform.  相似文献   
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OBJECTIVE: To assess risk factors for antepartum fetal deaths. METHODS: A population-based case-control study was carried out in the city of S?o Paulo from August 2000 to January 2001. Subjects were selected from a birth cohort from a linked birth and death certificate database. Cases were 164 antepartum fetal deaths and controls were drawn from a random sample of 313 births surviving at least 28 days. Information was collected from birth and death certificates, hospital records and home interviews. A hierarchical conceptual framework guided the logistic regression analysis. RESULTS: Statistically significant factors associated with antepartum fetal death were: mother without or recent marital union; mother's education under four years; mothers with previous low birth weight infant; mothers with hypertension, diabetes, bleeding during pregnancy; no or inadequate prenatal care; congenital malformation and intrauterine growth restriction. The highest population attributable fractions were for inadequacy of prenatal care (40%), hypertension (27%), intrauterine growth restriction (30%) and absence of a long-standing union (26%). CONCLUSIONS: Proximal biological risk factors are most important in antepartum fetal deaths. However, distal factors - mother's low education and marital status - are also significant. Improving access to and quality of prenatal care could have a large impact on fetal mortality.  相似文献   
7.
OBJECTIVE: To assess risk factors for early neonatal mortality. METHODS: A population-based case-control study was carried out with 146 early neonatal deaths and a sample of 313 controls obtained among survivals of the neonate period in the south region of the city of S?o Paulo, in the period of 8/1/2000 to 1/31/2001. Information was obtained through home interviews and hospital charts. Hierarchical assessment was performed in five groups with the following characteristics 1) socioeconomic conditions of mothers and families, 2) maternal psychosocial conditions, 3) obstetrical history and biological characteristics of mothers, 4) delivery conditions, 5) conditions of newborns RESULTS: Risk factors for early neonate mortality were: Group 1: poor education of household head (OR=1.6; 95% CI: 1.1;2.6), household located in a slum area (OR=2.0; 95% CI: 1.2;3.5) with up to one room (OR=2.2; 95% CI: 1.1;4.2); Group 2: mothers in recent union (OR=2.0; 95% CI: 1.0;4.2), unmarried mothers (OR=1.8; 95% CI: 1.1;3.0), and presence of domestic violence (OR=2.7; 95% CI: 1;6.5); Group 3: presence of complications in pregnancy (OR=8.2; 95% CI: 5.0;13.5), previous low birth weight (OR=2.4; 95% CI: 1.2;4.5), absence of pre-natal care (OR=16.1; 95% CI: 4.7;55.4), and inadequate pre-natal care (block 3) (OR=2.1; 95% CI: 2.0;3.5); Group 4: presence of clinical problems during delivery (OR=2.9; 95% CI: 1.4;5.1), mothers who went to hospital in ambulances (OR=3.8; 95% CI: 1.4;10.7); Group 5: low birth weight (OR=17.3; 95% CI: 8.4;35.6) and preterm live births (OR=8.8; 95% CI: 4.3;17.8). CONCLUSIONS: Additionally to proximal factors (low birth weight, preterm gestations, labor complications and unfavorable clinical conditions in gestation), the variables expressing social exclusion and presence of psychosocial factors were also identified. This context may affect the development of gestation and hinder the access of women to health services. Adequate prenatal care could minimize the effect of these variables.  相似文献   
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The purpose of this study was to investigate the effects of cooling and heating of muscles on parameters of surface EMG (SEMG) under various well defined grades of isometric muscle contraction. In 32 healthy volunteers, aged 20-30 years, turns and amplitude (RMS) analysis was done in SEMG from the hand extensors. Muscle strength was defined by a new developed hand dynamometer. Values for RMS and turns in case of maximal voluntary contraction (MVC) over periods of 20 sec were determined for each volunteer and subsequently RMS and turns were measured during isometric contractions of 10%, 30%, 50% and 80% of MVC, interrupted each by rest periods. This procedure was repeated after cooling and warming the forearm with thermo packs. For control purposes the same investigations with three measurement periods of SEMG were done following the same time schedule without thermic stimuli. With increasing isometric contractions turns increased after heat application and decreased after ice application, compared to the values achieved without thermic stimuli. The differences were significant from a level of 30% of MVC (p < 0.05). No corresponding changes were seen for RMS. In the control experiment values of turns and RMS did not differ in the three measurement periods. It is concluded, that the amplitude in SEMG tracings seems to be a reliable parameter of muscle force, whereas turns are sensitive to temperature. They might be useful markers for therapeutic approaches targeted at the muscle.  相似文献   
10.
IgG and IgA heavy chain allotypes were determined in the sera of 483 Caucasian Type 1 diabetes patients and 503 Caucasian healthy controls. There was no significant difference between patients and controls neither on the level of Gm phenotype frequencies nor on the level of Gm three-locus and two-locus haplotype frequencies. A selective IgA deficiency was found in 14 patients (2.9%) but in none of the control individuals (P<10-4).  相似文献   
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