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61.
In a group of six Parkinsonian patients and 13 "controls" with non-Parkinsonian neurological disease, there was a high correlation between both free and conjugated phenylacetic acid concentrations in plasma and cerebrospinal fluid taken at about the same time. This compound is the major metabolite of phenylethylamine, the production of which may be disturbed in a number of neuropsychiatric illnesses. Thus plasma measurements might be employed clinically to provide an estimate of central changes in phenylethylamine economy. A small but significantly higher proportion of conjugated phenylacetic acid was present in the plasma (but not cerebrospinal fluid) of Parkinsonians compared with controls.  相似文献   
62.
On the basis of information obtained during a study of former mental patients under a research grant from the state of Florida, the authors point out the critical need for more comprehensive management information systems. Twelve specific steps for designing and implementing such a system are outlined.  相似文献   
63.
Women with advanced breast cancer frequently experience psychologic distress as a result of their illness and its treatment. This distress may be manifest as depression, anxiety, symptoms of the stress-response syndrome, difficulty coping and social isolation. Six randomized trials of psychosocial interventions have been conducted in metastatic breast cancer. Five of these evaluated group psychosocial support – supportive-expressive therapy in three studies, cognitive-behavioral in one, and a combination of cognitive-behavioral and supportive therapy in another. All of these studies identified psychological benefits, notably improvement in mood, pain control and coping, although benefits were small in one study that provided the control group with a home cognitive-behavioral study program. One study identified an unexpected survival benefit associated with a group intervention – three subsequent studies have failed to replicate this result. Survival results of one additional ongoing study are pending.Studies in early breast cancer, and in patients with a spectrum of other cancers, have demonstrated benefits of individual psychological interventions, educational interventions and relaxation/self-hypnosis/imagery interventions, however, these have not been adequately evaluated in metastatic breast cancer.Based on these results, it is recommended that psychosocial support be offered to women with advanced breast cancer. Current research does not provide sufficient information to determine the optimal type of intervention to be used, or the optimal timing and duration of such interventions. Furthermore, it is not clear which patients benefit the most from psychosocial intervention and whether there are some patients who do not require psychosocial intervention. Research to address these issues is recommended.  相似文献   
64.
Duchenne and Becker muscular dystrophies are X-linked allelic disorders in which the association of central nervous system dysfunction, typically in the form of mental retardation, is a well recognized feature. They are both due to mutations in the dystrophin gene, whose corresponding protein products are expressed both in the muscle and central nervous system. We have observed an increased frequency of epilepsy in children with Duchenne and Becker muscular dystrophy attending our clinic. Out of 254 boys with this condition (201 Duchenne and 53 Becker), eight children, four in the Duchenne and four in the Becker group, had a confirmed diagnosis of epilepsy (cumulative incidence 3.14%, with a subgroup incidence of 1.99% in the Duchenne and 7.54% in the Becker group). Statistical analysis indicated that only the incidence of epilepsy in Becker muscular dystrophy was significant (p < 0.007). Our data suggests that epilepsy may be a rare associated feature in children with muscular dystrophy secondary to dystrophin deficiency.  相似文献   
65.
PURPOSE: Evaluation of the healing and persistence of a meshed composite skin graft applied without immunosuppression. METHODS: The contraction of wounds grafted with 9:1 split-thickness autograft/1.5:1 allodermal mesh composite skin grafts (auto/allo MCSGs) was investigated. No immunosuppressive agent was applied. Male ACI rats and female Lewis rats reciprocally served as allodermis graft donors and recipients. Autograft/dermal autograft and allograft/dermal allograft MCSGs were the controls. RESULTS:AT 3 months after grafting, when epithelized auto/allo MCSG wounds were measured by computerized morphometric analysis, the silver nylon (SN) dressing group displayed less contraction than the Vaseline (petroleum jelly) dressing group (p < 0.003), and direct current treatment (SNDC) was more effective than SN (p < 0.005). The histologic structures of the hair follicles appear to confine the rejection process to the allogeneic follicles of the graft. The focal nature of the rejection process and the relatively low antigenicity of the dermal matrix allowed the survival of the allodermis layer. Although direct current significantly enhanced MCSG healing, SN and SNDC were not the immunosuppressive agents that were confirmed. CONCLUSION: This type of MCSG can heal without immunosuppressive treatment.  相似文献   
66.
Gore DC  Ferrando A  Barnett J  Wolf SE  Desai M  Herndon DN  Goodwin C  Wolfe RR 《The Journal of trauma》2000,49(4):673-7; discussion 677-8
BACKGROUND: In critically ill patients, elevation in the plasma lactate concentration has traditionally been interpreted as indicating a deficiency in oxygen availability and is often an impetus to increase oxygen delivery clinically. However, another possible basis for increased lactate concentrations may be simply a mass effect from increased pyruvate availability (i.e., accelerated glycolysis). METHODS: In six hypermetabolic burned patients, the rates of glucose production and oxidation were quantified using a tracer infusion of 6,6 d2 glucose combined with indirect calorimetry. Measurements were obtained after a 9-hour fast and after a 3-hour infusion of unlabeled glucose at 30 micromol/kg/min. No patient was overtly septic, hypoxic, or hypovolemic. RESULTS: The infusion of glucose significantly increased the arterial glucose concentration and rate of glucose oxidation, with a corresponding increase in the arterial plasma concentration of lactate and pyruvate. Resting energy expenditure and oxygen consumption were not affected by the infusion of glucose. CONCLUSIONS: These findings show that elevations in plasma lactate in severely injured patients may, in part, be related to increases in glucose flux and not entirely a reflection of any deficit in oxygen availability. Such findings highlight a potential pitfall for interpreting plasma lactate concentrations as an index of tissue oxygen availability in hypermetabolic patients.  相似文献   
67.

Background  

Researchers and clinicians are seeking to develop efficacious behavioral interventions to treat overweight children; however, few studies have documented the behavioral correlates of overweight children in community samples. The goal of this study was to determine the nature and prevalence of behavior problems for overweight school-aged children versus normal weight peers before and after controlling for the effect of sleep disordered breathing.  相似文献   
68.
A significant challenge in natural product discovery is the initial discrimination of discrete secondary metabolites alongside functionally similar primary metabolic cellular components within complex biological samples. A property that has yet to be fully exploited for natural product identification and characterization is the gas-phase collision cross section, or, more generally, the mobility-mass correlation. Peptide natural products possess many of the properties that distinguish natural products, as they are frequently characterized by a high degree of intramolecular bonding and possess extended and compact conformations among other structural modifications. This report describes a rapid structural mass spectrometry technique based on ion mobility-mass spectrometry for the comparison of peptide natural products to their primary metabolic congeners using mobility-mass correlation. This property is empirically determined using ion mobility-mass spectrometry, applied to the analysis of linear versus modified peptides, and used to discriminate peptide natural products in a crude microbial extract. Complementary computational approaches are utilized to understand the structural basis for the separation of primary metabolism derived linear peptides from secondary metabolite cyclic and modified cyclic species. These findings provide a platform for enhancing the identification of secondary metabolic peptides with distinct mobility-mass ratios within complex biological samples.  相似文献   
69.
Biochemical and behavioral effects of intrahippocampal AF64A in rats   总被引:1,自引:0,他引:1  
AF64A (ethylcholine aziridinium, 1 nmole) injected into the dorsal hippocampus of the rat decreased choline acetyltransferase activity there by 20% without greatly affecting adjacent areas. The decrease was maximal by 3 days, and persisted for at least 3 weeks. The acetylcholine concentration at the injection site was decreased by 25-30% from 3 days to 4 weeks. Rats were trained on a continuous reinforcement (CRF) food-reinforced lever press schedule and then injected bilaterally in the dorsal and ventral hippocampus. Subsequent switching to a daily CRF-extinction schedule resulted in increased responding during extinction compared to controls which persisted for at least 13 session. However, injection after switching schedules increased it for only 2 sessions. This indicates that the persistently increased extinction responding is due mainly to impaired learned habituation to a new schedule. Most of the extinction effect of the intrahippocampal AF64A was due to its injection at the dorsal site. Separate rats which were trained on the 8-arm radial maze task (a test of short-term spatial working memory) and injected as above only showed marginally impaired task performance even at higher doses. We conclude that even relatively minor, localized, cholinergic deficits confined to the hippocampus can produce significant learning and memory impairments in situations where intermediate or long term memory formation is required.  相似文献   
70.

Objective

The goal of this study was to determine the prevalence of severe nausea and vomiting of pregnancy/hyperemesis gravidarum among relatives of affected individuals.

Study design

Family history data were obtained on 1224 self-reported cases of hyperemesis gravidarum. Cases completed an online survey administered by the Hyperemesis Education and Research Foundation between 2003 and 2006.

Results

Approximately 28% of cases reported their mother had severe nausea and vomiting or hyperemesis gravidarum while pregnant with them. Of the 721 sisters with a pregnancy history, 137 (19%) had hyperemesis gravidarum. Among the most severe cases, those requiring total parenteral nutrition or nasogastric feeding tube, the proportion of affected sisters was even higher, 49/198 (25%). Nine percent of cases reported having at least two affected relatives including sister(s), mother, grandmother, daughters, aunt(s), and cousin(s).

Conclusion

There is a high prevalence of severe nausea and vomiting of pregnancy/hyperemesis gravidarum among relatives of hyperemesis gravidarum cases in this study population. Because the incidence of hyperemesis gravidarum is most commonly reported to be 0.5%, this study provides strong but preliminary evidence for a genetic component to extreme nausea and vomiting of pregnancy.  相似文献   
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