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771.
BACKGROUND: The relationship between plasma homovanillic acid (pHVA) and schizophrenic symptoms has not been conclusively determined. We reexamine pHVA levels in a new sample of patients with emphasis on demographic variables and the drug-free period. METHODS: Plasma HVA levels were studied in 54 schizophrenic and schizoaffective-disordered, drug-free inpatients suffering from a psychotic exacerbation. RESULTS: A significant correlation was observed between pHVA levels and the number of inpatient drug-free days in the total sample, as well as the schizophrenic patient subsample. Further, pHVA was significantly and positively correlated with the duration of illness in the schizophrenic patient subsample. Plasma HVA correlations with behavior, as measured by Brief Psychiatric Rating Scale factors (anxiety/depression and hostility/suspiciousness), emerged only when considering schizophrenic patients drug-free for more than 2 weeks. No correlation was found between pHVA and the age of illness onset or the duration of the delay of treatment of the first psychotic episode. CONCLUSIONS: The effects of antipsychotic withdrawal on levels of pHVA in clinical populations may have to be examined and controlled for in future studies attempting to study the relationship between this metabolite and behavior in acutely ill, drug-free schizophrenic patients.  相似文献   
772.
Seven patients with suspected recurrent rectal cancer underwent Helical CT using SmartPrep. SmartPrep is a software application developed by GE in which the ROI is placed at the desired level of the aorta prior to contrast injection. Using a low-dose continuous scan, the time density curve was obtained instantly, and the optimal timing of scanning was judged from the curve. Four patients who demonstrated intense enhancement at the anastomotic site had local recurrence. No intense enhancement was observed in these areas on conventional delayed CT. Thus, SmartPrep appears to be useful for the accurate diagnosis of recurrent rectal cancer.  相似文献   
773.
Certain mutations in the C-terminal region of the Escherichia coli division inhibitor protein MinC cause loss of function of the division inhibitor by making MinC more sensitive to degradation by Lon protease, implying a possible role for the C-terminal region in regulating the stability and cellular concentration of MinC.  相似文献   
774.
PURPOSE: To determine the safety, effectiveness, and problems encountered with endovascular repair of abdominal aortic aneurysm (AAA). Initial experience with endoluminal stent grafts was examined and compared with outcome for a matched concurrent control group undergoing conventional operative repair of AAA. METHODS: Over a 3-year period, 30 patients underwent attempts at endovascular repair of infrarenal AAA. Of the 28 (93%) successfully implanted endografts, 8 were tube endografts, 8 bifurcated grafts, and 12 aortouniiliac grafts combined with femorofemoral bypass. Most of the procedures were performed in the past year because the availability of bifurcated and aortoiliac endografts markedly expanded the percentage of patients with AAA who might be treated with endoluminal methods. The follow-up period ranged from 1 to 44 months, with a mean value of 11 months. RESULTS: Endovascular procedures demonstrated significant advantages with respect to reduced blood loss (408 versus 1287 ml), use of an intensive care unit (0.1 versus 1.75 days), length of hospitalization (3.9 versus 10.3 days), and quicker recovery (11 versus 47 days). Although the total number of postoperative complications was identical for the two groups, the nature of the complications differed considerably. Local and vascular complications characteristic of endovascular repair could frequently be corrected at the time of the procedure and tended to be less severe than systemic or remote complications, which predominated among the open surgical repair group. On an intent-to-treat basis, 23 (77%) of the 30 AAAs were successfully managed with endoluminal repair. The seven (23%) failures were attributable to two immediate conversions caused by access problems, three persistent endoleaks, one late conversion caused by AAA expansion, and one late rupture. CONCLUSIONS: Although less definitive than those for conventional operations, these early results suggest that endovascular AAA repair offers considerable benefits for appropriate patients. The results justify continued application of this method of AAA repair, particularly in the treatment of older persons at high risk.  相似文献   
775.
OBJECTIVE: The aim of this study was to compare levels of CSF somatostatin (somatotropin release-inhibiting factor) in drug-free patients with different major psychiatric disorders. METHOD: CSF somatostatin concentrations were measured in 66 drug-free inpatients with Research Diagnostic Criteria diagnoses of schizophrenia, major depressive disorder, manic disorder, or schizoaffective disorder. RESULTS: In comparison with both the patients with schizophrenia and the patients with schizoaffective disorder, the manic patients had markedly elevated CSF somatostatin concentrations. The depressed patients had significantly higher levels than the schizophrenic patients. CONCLUSIONS: Mania is associated with relatively higher CSF somatostatin concentrations.  相似文献   
776.
OBJECTIVE: To examine self- and other-directed aggression in 89 children and adolescents on a psychiatric inpatient unit to determine ways in which aggressive and nonaggressive patients differ and to discover those factors associated with self-directed versus other-directed aggression. METHOD: Three types of data were collected: ongoing observations of aggressive behavior during hospitalization, Child Behavior Checklists completed by a parent or guardian at admission, and patient and family history data gathered from a retrospective chart review. RESULTS: Compared with nonaggressive patients, aggressive patients were more likely to have a history of antisocial behavior, to be victims of abuse or neglect, to have lived in a foster home, and to have had several primary caretakers. Both groups of aggressive patients engaged in three types of aggressive behavior with equal frequency and were strikingly similar on a host of other variables. Only the number of primary caretakers with whom a patient had lived discriminated self- from other-directed aggressive patients; patients who experienced frequent disruptions in caretaking were likely to engage in acts of self-injury during hospitalization. CONCLUSIONS: Whether a particular patient will engage in aggressive behavior during hospitalization can be accurately predicted from preadmission characteristics; however, the manner in which a patient is likely to aggress, i.e., toward others or self, is difficult to predict because of striking similarities between types of aggressive patients. Further investigations are needed to determine how self- and other-directed aggressive patients differ and to elucidate relationships between disrupted, unstable, or inadequate caretaking and aggression, particularly self-injury, in children and adolescents.  相似文献   
777.
778.
The outcome of 114 patients with tumour-induced hypercalcaemia (TIH) treated between January 1992 and June 1993 with intravenous pamidronate (APD) was retrospectively analysed. The median overall survival was 55 days (range 3 days to > 21 months): 86 days if systemic anti-cancer therapy was available and only 35 days if not (P < 0.001). Survival was also significantly better for those who became normocalcaemic post APD (53 days vs 19 days, P < 0.001). There was no survival difference with respect to patient sex, age, tumour type, treatment of bone metastases with radiotherapy, initial calcium level, initial dose of APD or time from tumour diagnosis to first TIH. In those patients in whom systemic anti-cancer therapy is available, treatment with APD improves survival, but in all other patients the primary aim of treatment should be symptom control. This study confirms the dismal prognosis of TIH.  相似文献   
779.
BACKGROUND: Self-reported physical health status of Australian Vietnam veterans was determined 20-25 years after the war and its relation to combat was investigated. METHOD: An epidemiological cohort study of a simple random sample of Army veterans posted to Vietnam between 1964 and 1972 was conducted with personal interviews using the Australian Bureau of Statistics Health Interview Survey questionnaire to compare veterans with the Australian population and a 21-item combat exposure index used to measure the relationship of combat to physical health. RESULTS: Veterans reported greater health service usage and more recent health actions than population expectations. They also reported excess health problems in almost all recent illness disease categories except endocrine conditions and cardiovascular conditions; only 6 of 37 chronic disease groups were not elevated compared to the population. Adjustment for non-response changed estimates only slightly. Combat exposure was significantly related to reports of recent and chronic mental disorders, recent hernia and chronic ulcer, recent eczema and chronic rash, deafness, chronic infective and parasitic disease, chronic back disorders and symptoms, signs and ill-defined conditions. CONCLUSION: Combat exposure may have significantly increased reports of only some health problems. A general position to complain as a result of psychological conditions due to combat is not consistent with the lack of relationship between combat and reports of physical conditions.  相似文献   
780.
PURPOSE: To evaluate the toxicity of stereotactic single-dose irradiation and to compare the own results with already existing risk prediction models. METHODS AND MATERIALS: Computed tomography (CT) or magnetic-resonance (MR) images, and clinical data of 133 consecutive patients treated with linear accelerator radiosurgery were analyzed retrospectively. Using the Cox proportional hazards model the relevance of treatment parameters and dose-volume relationships on the occurrence of radiation-induced tissue changes (edema, localized blood-brain barrier breakdown) were assessed. RESULTS: Sixty-two intraparenchymal lesions (arteriovenous malformation (AVM): 56 patients, meningioma: 6 patients) and 73 skull base tumors were selected for analysis. The median follow-up was 28.1 months (range: 9.0-58.9 months). Radiation-induced tissue changes (32 out of 135, 23.7%) were documented on CT or MR images 3.6-58.7 months after radiosurgery (median time: 17.8 months). The actuarial risk at 2 years for the development of neuroradiological changes was 25.8% for all evaluated patients, 38.4% for intraparenchymal lesions, and 14.6% for skull base tumors. The coefficient: total volume recieving a minimum dose of 10 Gy (VTREAT10) reached statistical significance in a Cox proportional hazards model calculated for all patients, intraparenchymal lesions, and AVMs. In skull base tumors, the volume of normal brain tissue covered by the 10 Gy isodose line (VBRAIN10) was the only significant variable. CONCLUSIONS: These results demonstrate the particular vulnerability of normal brain tissue to single dose irradiation. Optimal conformation of the therapeutic isodose line to the 3D configuration of the target volume may help to reduce side effects.  相似文献   
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