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21.
The present study, using a diathesis-stress model, attempted to confirm prior findings with platelet monoamine oxidase (MAO) activity and stress in a middle-aged, non-clinic population. One hundred and seventy-eight adult males from a statewide community club were tested for platelet MAO activity and stressful life events and were also given a variety of psychological measures of both psychopathology and psychosocial coping. The data were examined both for correlations across the total sample and for a comparison of high-risk groups (top and bottom 15% of MAO activity) with a middle MAO group. Low platelet MAO activity was related to a higher incidence of contact with mental health professionals, and more frequent use of alcohol and cigarette smoking. High MAO activity was related to higher levels of anxiety and somatization. High levels of stress were related to increased psychosocial problems reported for female and family members, higher scores on two schizophrenia-related MMPI scales (schizophrenia and paranoia subscales), but fewer idiosyncratic associations, elevated hypomanic, depression, and anxiety scores, increased alcohol use, and increased use of prescribed antianxiety and sedative medication. Neither MAO nor stress were related to current levels of psychosocial coping. Moreover, no interaction effects were uncovered for MAO activity and stress combined.  相似文献   
22.
Our previous results indicated that the trihydroxamate ligand, trisuccin, was a promising bifunctional chelating agent (BCA) for radiometal labeling of monoclonal antibodies with rhenium and technetium. An interest was developed to evaluate structural modifications of this compound from both synthetic and biological points of view. In this report we describe the synthesis of an esterified trisuccin (referred to as trisester), and conjugation of this new derivative to MAb CC49, radiolabeling of this conjugate with rhenium-188 (188Re), and biodistribution of the labeled conjugate in athymic nude mice. Thus, trisuccin (1) was esterified with benzyl 4-hydroxybenzoate in a DCC/DMAP reaction followed by removal of all benzyl protecting groups with catalytic hydrogenation. The resulting product was conjugated to CC49 by the active ester technique, through formation of the 2-nitrophenyl ester 6, and the conjugate was radiolabeled with generator-produced 188Re. The lead molecule trisuccin 1 was also conjugated to CC49 through the active ester 5 and the conjugate was radiolabeled by the same procedure to serve as the control conjugate. Biodistributions of the labeled conjugates were studied in athymic nude mice, transplanted s.c. with LS174T human colon cancer xenografts. Although an increase in the radiolabeling yield was observed for the esterified ligand-CC49 conjugate, as well as some increase in its immunoreactivity, as compared to those for the parent trisuccin molecule, there were no significant differences in their biodistribution. This new compound therefore may be useful in improving the conjugation and radiolabeling chemistries of this trihydroxamate ligand system.  相似文献   
23.
A new bifunctional chelating agent MAGIPG was synthesized in good yield using Boc-p-nitro-phenylalanine as the starting material. 99mTc-labeled-MAGIPG-D612 conjugates reactive with human colon cancer were prepared in 3% to 15% yield with a radiochemical purity of 63% to 97%. 186Re-labeled MAGIPG-D612 conjugates were prepared with a 7% to 30% yield and a radiochemical purity of 82% to 98%. The biodistribution results demonstrate that these radioimmuno-conjugates selectively localized in LS174T human colon cancer xenografts.  相似文献   
24.
8 mg of naloxone were administered IV to 14 normal volunteers in a placebo-controlled, double-blind experiment. Plasma levels of -endorphin, cortisol, prolactin, growth hormone, HVA and MHPG were determined before and 45 min after administration. Naloxone elicited significant increases in cortisol and MHPG but did not change plasma levels of the other compounds. In an additional experiment on two subjects, 20 mg of naloxone caused elevations of -endorphin as well as of cortisol. This parallel increase indicates that the linkage between the secretion of -endorphin and ACTH/cortisol may be dose-dependent. The increase in MHPG is in agreement with the hypothesized association of noradrenergic hyperactivity and opiate withdrawal.  相似文献   
25.
Digital data from 3‐D treatment planning computers is generally used for patient planning and then never considered again. However, such data contains enormous quantities of information regarding patient geometries, tissue outlining, treatment approaches and dose distributions. Were such data accessible from planning systems from multiple manufacturers, there would be substantial opportunities for undertaking quality assurance of radiotherapy clinical trials, prospective assessment of trial outcomes and basic treatment planning research and development. The technicalities of data exchange between planning systems are outlined, and previous attempts at producing systems capable of viewing and/or manipulating imaging and radiotherapy digital data reviewed. Development of a software system for enhancing the quality of Australasian clinical trials is proposed.  相似文献   
26.
Tacrolimus-associated mutism after orthotopic liver transplantation   总被引:8,自引:0,他引:8  
BACKGROUND: Mutism/speech apraxia has been well documented as a toxic effect of cyclosporine after liver transplantation but has been reported only rarely with tacrolimus. Brain imaging with magnetic resonance or computed tomography has failed to demonstrate abnormalities in affected patients. METHODS: We present the first example of an acute onset of loss of speech associated with a sudden elevation of serum tacrolimus level after successful orthotopic liver transplantation. We also describe the positron emission tomography (PET) scan of this patient's brain. RESULTS: PET scan imaging of the brain was abnormal, demonstrating decreased metabolism in the posterior temporo-parieto-occipital regions. Statistical probability mapping revealed additional areas of hypometabolism in the cingulate gyrus. CONCLUSIONS: PET scan revealed abnormalities of the brain in a patient with tacrolimus-induced mutism. The cingulate gyrus may play a role in the mutism/speech apraxia syndrome seen with cyclosporine/tacrolimus neurotoxicity.  相似文献   
27.
The purpose of this study was to prospectively examine the effectiveness and tolerability of a simple radiotherapy technique for the palliation of symptomatic liver metastases. Twenty‐eight patients with symptomatic liver metastases were enrolled from seven centres, and received targeted (partial or whole) liver irradiation consisting of 10 Gy in two fractions over 2 days. Symptoms at baseline were hepatic pain (27 patients), abdominal distension (19), night sweats (12), nausea (18) and vomiting (eight). Twenty‐two patients (76%) had failed previous treatment with chemotherapy, hormonal therapy and/or high‐dose steroids. Symptoms and potential toxicities were prospectively assessed at the time of treatment, then 2, 6 and 10 weeks later. Individual symptom response rates were 53?66% at 2 weeks. Partial or complete global symptomatic responses were noted in 15 patients (54%) overall. The treatment was well tolerated with two patients (7%) experiencing grade 3 toxicity (one vomiting and one diarrhoea); however, four patients reported temporary worsening of pain shortly after treatment. This simple and well‐tolerated treatment achieves useful palliation.  相似文献   
28.
Objective : The aim of this study was to investigate the inter-relationship between urinary excretion of alpha-1-microglobulin (AIM), retinol-binding protein (RBP) and albumin in term and premature neonates, with urine collected into cotton wool balls and extracted by a novel method. Subjects and methods : Sixty-four infants were studied on the first day of life; 26 had been born at term (37–42 weeks gestation) and 38 prematurely (24–28 weeks n = 16, 29–36 weeks n = 22). Urine collected into cotton wool balls was analysed following a new detergent extraction method, which resulted in a recovery rate of 94–107% for albumin, AIM, RBP and creatinine. Results : Urinary protein excretion, expressed as a ratio to urinary creatinine, decreased significantly with increasing gestational age (24–28 weeks, 29–36 weeks, 37–42 weeks: albuminxreatinine ratio mg/mmol mean 96.9, 31.7, 19.3; AIM: creatinine ratio mg/mmol mean 99.3, 37.0, 7.8; RBP: creatinine ratio mg/mmol mean 16.2, 3.8, and <0.01, below the limit of detection, respectively). When results were corrected for birthweight, this gestation-associated effect was still present for A1M and RBP, but not for albumin. In premature infants there was a significant positive correlation between AIM: creatinine ratio and RBP: creatinine ratio ( r = 0.85), and also between albumin and both AIM and RBP ( r = 0.82 and 0.77). Conclusion : Increased excretion of AIM, RBP and albumin at earlier gestational ages is probably due to proximal tubular immaturity, although tubular damage and also glomerular dysfunction cannot be excluded as possible explanations.  相似文献   
29.
Objectives: To assess: (i) the size of placental transfusion following a 30 s delay in cord clamping following vaginal and Caesarean births; and (ii) the feasibility of delaying cord clamping in the labour ward and particularly in the operating theatre.
Methods: Fourty-six infants born at 26–33 weeks gestation were randomized to having the umbilical cord clamped either immediately or 30 s after birth. The venous haematocrit was measured at 1 and at 4 h of age.
Results: There were trends towards higher mean haematocrits in the infants following delayed clamping, but these were not significant either at 1 h (55±7.7 vs 52.9±7) or at 4 h of age (55±7 vs 52.5±7). The trends were more marked in the infants born by Caesarean section, and in those born at 26–29 weeks gestation.
Conclusions: A 30 s delay in cord clamping is feasible at both vaginal and Caesarean births, but does not lead to the predicted difference in infant haematocrit. Although physiological studies suggest that a placental transfusion of 15–20 mL/kg occurs within 30 s of delivery, these data suggest that future trials should either delay cord clamping for more than 30 s, or should alter the position of the infant in relation to the uterus in order to facilitate the transfusion. Delayed cord clamping is feasible at Caesarean section.  相似文献   
30.
Objective: To evaluate the incidence and severity of apnoea and bradycardia in hospitalized preterm infants following immunization at 2 months of age, and identify risk factors.
Methodology: A prospective study of 98 preterm infants, of gestational age 24–31 weeks, immunized at approximately 2 months post natal age with diphtheria-tetanus-whole cell pertussis vaccine (DTPw) in the neonatal intensive care unit (NICU) at King George V Hospital Sydney. Half the infants also received Haemophilus influenzae type b conjugate vaccine (Hib) simultaneously. All infants were monitored for apnoea and bradycardia in the 24 h periods pre- and post immunization.
Results: Only one infant had apnoea and/or bradycardia pre-immunization compared with 17 post immunization. For 12 infants these events were brief, self-limiting and not associated with desaturations (oxygen saturation <90%). However, for five infants (30%) these events were associated with oxygen desaturation and two of these infants required supplemental oxygen. The group that had apnoea and/or bradycardia and the group that did not were not significantly different in terms of gestational age, birth weight and other variables. Infants who received Hib together with DTPw were less likely to have apnoea and/or bradycardia than those given DTPw alone.
Conclusion: When considering immunization for preterm infants, the benefits of early immunization must be balanced against the risk of apnoea and bradycardia. We recommend that the cardio-respiratory function of hospitalized infants born at less than 31 weeks gestation be monitored for 48 h post immunization.  相似文献   
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