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111.
In many mammals, hormonal fluctuations during pregnancy and parturition produce neurochemical events that are necessary for the transition from a non-maternal state to a maternal state that occurs when infants are born. However, the nature of these events is mostly unknown. We investigated whether changes in dopamine (DA) and serotonin (5-HT) activity within the preoptic area (POA) and striatum, neural sites important for some maternal behaviors, could be part of this process. Female rats were sacrificed as either diestrus virgins, on pregnancy day 10 or 20, on the day of parturition, or on day 7 or 17 of lactation. Bilateral tissue punches from the POA, dorsolateral striatum (STdl), and nucleus accumbens (NA) were obtained and levels of intracellular DA and 5-HT analyzed with high-performance liquid chromatography with electrochemical detection (HPLC–EC). In the POA, DA was high in virgins and during early pregnancy, lowest on the day of parturition, and very high during lactation. Although there were no changes in the DOPAC to DA ratio (i.e., turnover), DOPAC levels also followed this pattern. 5-HT turnover in the POA was lower in virgins compared to other groups. In the STdl, DA turnover was highest during late pregnancy and on the day of parturition, while no changes in 5-HT measures were found. No significant effects were found in the NA. Therefore, decreased DAergic activity in the POA and increased DAergic activity in the STdl occurs around parturition, the time when maternal behavior emerges, and may influence its onset. 相似文献
112.
Putnam A 《American family physician》2003,67(9):2025-6, 2028
113.
The nature of the affective deficit that characterizes social anhedonia is not well understood. Emotionally evocative visual stimuli were presented to undergraduates identified as anhedonic or normal, based on their scores on the revised Social Anhedonia Scale. The affective stimuli were chosen to elicit positive and negative emotion; a subset of slides were specifically chosen to include social-interpersonal content. In the acoustic startle paradigm, participants were administered startle probes (50-ms 95 dB white noise bursts) while viewing images from the International Affective Picture System. Socially anhedonic individuals did not differ from normally hedonic individuals in terms of their physiological response to the stimuli, regardless of the nature of the content of the stimuli. However, on the self-report measures of trait affectivity, the socially anhedonic individuals reported significantly lower levels of positive affect and higher levels of negative affect. These findings suggest that the affective deficits reported by socially anhedonic individuals are not global in nature. 相似文献
114.
Two robust findings in the Alzheimer’s literature are that patients with Alzheimer’s disease (AD) show executive function and primacy deficits. The present study examined whether we would find similar deficits when comparing two groups of middle-aged individuals who differed with respect to genetic risk for AD, based on their apolipoprotein E (APOE) genotype. All individuals were screened as normal on a battery of standardized cognitive measures. They were tested on the “Operation span task”, which engages the central executive component of working memory [J. Exp. Psychol.: Gen. 128 (1999) 309, J. Exp. Psychol.: Gen. 126 (1997) 211, J. Mem. Language 39 (1998) 418] by dividing attention between processing math operations and remembering words. Individuals were grouped according to APOE genotype (4 carrier versus 4 non-carrier), matched on age and education, and their Total span and Primacy scores were compared. Despite having no overt symptoms of dementia or deficits on a series of standardized psychometric tests, the 4 carriers showed divided-attention and primacy deficits on the Operation span task, when compared to the 4 non-carriers. As a point of comparison, Primacy scores were extracted from the first trial of the “Buschke selective reminding task” [J. Verbal Learn. Verbal Behav. 12 (1973) 543] for these same individuals, and no group differences were found. The Buschke task is a list-learning task that does not require divided attention. These findings suggested that the 4 carriers were less able to divide their attention, when compared to the 4 non-carriers. The findings provide the first direct evidence for a relationship between APOE genotype and cognitive performance on measures of divided attention and primacy with non-demented individuals who showed no cognitive impairments on standardized measures. 相似文献
115.
116.
JR Bapuraj V Ojili SK Singh GRV Prasad N Khandelwal S Suri 《Journal of Medical Imaging and Radiation Oncology》2006,50(2):179-182
Leiomyoma of the vagina is a very rare tumour of the lower urogenital tract. These slow‐growing masses may be asymptomatic or present with pain, dyspareunia or urinary symptoms. Rarely, these tumours may present with life‐threatening haemorrhage. These hypervascular tumours are treated by surgical excision. Preoperative embolization therefore may aid in devascularization of these tumours before surgical excision. We present the MRI features of a case of vaginal leiomyoma, which was managed by preoperative embolization and was then excised in toto. To the best of our knowledge, this is the first report where preoperative embolization was performed before excision of a vaginal leiomyoma with minimal peroperative blood loss. 相似文献
117.
RJ Gilbertson E Harris SK Pandey P Kelly W Myers 《Archives of disease in childhood》1996,75(3):194-198
Paracetamol is the commonest agent employed in self poisoning, however it is not clear whether adolescents possess insight into the serious complications associated with its misuse. Using a one page questionnaire, the availability, usage, and knowledge of toxicity of paracetamol among 1147 American and British adolescents was assessed. Although 90% of all students recognised that paracetamol could kill, the great majority of students overestimated the lethal dose. In addition, while knowledge regarding side effects of paracetamol was poor the drug was widely available to, and used by, the study population. It is proposed that gross overestimation of the number of tablets required to kill, poor understanding of paracetamol side effects, and wide availability of the drug contribute to its frequent use in adolescent suicidal behaviour. The inclusion of some over-the-counter medications in school drug education programs in addition to tighter control of the availability of paracetamol may help reduce the problem of adolescent self poisoning. 相似文献
118.
Small cell carcinoma of the esophagus: the University of Texas M. D. Anderson Cancer Center experience and literature review 总被引:17,自引:0,他引:17
BACKGROUND: Small cell carcinoma of the esophagus is a rare disease with aggressive behavior and poor prognosis. Multidrug chemotherapy remains the treatment of choice given the systemic nature of the disease. Radiotherapy has been used concurrently with chemotherapy to enhance local control. The role of surgery in patients with limited disease is controversial. Limited data exist regarding the pathologic response of the tumor to chemoradiotherapy. The goal of the current study was to analyze the outcome of 8 patients treated at the M. D. Anderson Cancer Center, with particular focus on the histologic findings of the resected specimens. METHODS: Patient records were reviewed for demographics, presenting symptoms, diagnostic modalities, disease stage, treatment, and outcome. RESULTS: Two of eight patients had metastatic disease at the time of diagnosis and received combination chemotherapy. Six patients had limited stage disease. Four received combined modality treatment including esophagectomy, and two received radiotherapy only. All four patients who underwent esophagectomy had pure small cell carcinoma histology at diagnosis and received preoperative combination chemotherapy with or without radiotherapy. None of the four patients achieved a pathologic complete remission. Two patients had residual small cell carcinoma; one patient had squamous cell carcinoma and one adenocarcinoma. The median overall survival for the group of patients was 12.5 months (range, 5-57 months). CONCLUSIONS: In selected patients with limited stage disease, surgery with curative intent should be considered as part of multimodality treatment. 相似文献
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120.