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61.
Male cricket frogs (Acris crepitans) produce a broad-band, high frequency advertisement call with a single spectral peak (the dominant frequency). We measured the dominant frequencies of male calls from six populations in central Texas and one from Indiana and compared them to the tuning of basilar papilla afferents in males and females. Averaging over all populations, mean call dominant frequency was 3.69 kHz, mean male basilar papilla tuning was 3.63 kHz, and mean female basilar papilla tuning was 3.17 kHz. Among populations, mean dominant frequency varied from 3.56 kHz to 3.82 kHz. Dominant frequencies were slightly higher in the more eastern Texas populations occupying pine forest habitats than in the more western populations occupying open grassland habitats. Changes in dominant frequency in a population coincided with changes in tuning of both male and female basilar papillae. Furthermore, within populations females were tuned on average lower than males and lower than the mean dominant frequency of calls in their own population. We suggest that the coincident changes in calls and basilar papilla tuning plus the sexual difference in tuning indicate that female mate choice would be directed toward males from her home population with low frequency calls or toward males from foreign populations with average calls lower in frequency than those in her home population. This in turn suggests that any gene flow between populations would be biased from east to west and from forest to open habitats.  相似文献   
62.
This study reviewed a series of patients with Crohn's disease managed by surgeons of the Department of Colon and Rectal Surgery, St Vincent's Hospital, Melbourne, since 1978. There were 306 patients: 171 males and 135 females. The mean age at diagnosis was 33.4 years (range 11–93). The distribution of the disease was small bowel 32.3%, small bowel and colon 26.5%, colon 39.9%, and anal disease alone 1.6%. A total of 416 abdominal operations were performed on 204 patients. The commonest indications for surgery were failed medical therapy (21.9%), small bowel obstruction (15.9%), enteric tistula (10.1%), and intra-abdominal abscess (10.1%). The most frequently performed procedures were ileocolic resection with anastomosis (28.8%), small bowel resection (9.4%), and total colectomy and ileostomy (7.0%). Postoperative complications included anastomotic leaks in 4.0%. intra-abdominal abscess formation in 3.6%, and enterocutaneous fistulae developed in 6%. Three patients died during the review period. During follow up (mean 84.4). 30% of patients developed recurrence requiring further surgery at a mean of 72.7 months postoperatively. The most frequent site for a recurrence was the pre-anastomotic terminal ileum (61.7%). In conclusion. the majority of patients with Crohn's disease will require resectional surgery at some stage. This can be performed with a low mortality and morbidity, and a recurrence rate of around 5% per year.  相似文献   
63.
Diagnosis of dementia needs to be complemented by precise determination of disease severity across the broad spectrum of disease progression. The Mini-Mental State Exam (MMS), the Activities-of-Daily-Living assessment (ADL) and the Clinical Dementia Rating scale (CDR) were modified for direct comparability and administered to 112 outpatients and 45 nursing home residents with a range of dementia severity from mild to profound. The scales showed the highest correlations for the probable Alzheimer's disease patient group (62) (Global Assessment of Dementia; GAD vs. ADL: r = 0.91; Extended Mini-Mental Assessment; EMA vs. GAD: r = 0.91; ADL vs. EMA: r = 0.86). For these patients, scores on the individual scales tended to be similar. Disparity among the three scores for individual cases was associated with the presence of comorbidities. The high correlations and correspondence among these scales demonstrate their reliability, validity, and utility in the assessment of dementia severity. The use of an average of these measures, with their increased precision, may give a more accurate indication of dementia severity over a broader range of impairment.  相似文献   
64.
目的 了解上海地区学生午餐营养及供应链状况,为改善学生午餐营养状况,保障食品供应安全提供参考。方法 分析上海市学生午餐的营养、卫生、供应链、加工工艺等状况,采用定期抽检的方法,应用SNHAS对营养素、食品安全、感官进行综合评价。结果 各单位样本综合评价均合格,其中热量、蛋白质、脂肪均能达到或超过DRIs供给量的要求,但矿物质中Ca(仅为AI的32%)、视黄醇当量(仅为AI的57%)供给量较低。对供应链及卫生状况的分析表明,大型企业对各个环节控制严格,产品质量较好,但也存在保存时间过长等问题。结论 应进一步完善供应体系,建立高效的质量控制体系,推广营养配膳系统。  相似文献   
65.
Macrophage infiltration is frequent in the early stages of various proliferative eye disorders, including subretinal neovascularization. In this study, we set out to establish the origin of macrophages found in an animal model of laser-induced subretinal neovascularization. One primate received several intravenous injections of a colloidal carbon suspension. We then applied standard argon laser lesions to the retina of both eyes, which were enucleated eight days later and sectioned serially for histological examination. A quantitative estimate of carbon-laden and non-laden leukocytes was made based on morphological criteria. Mononuclear leukocytes accumulated in the laser lesions and the percentage of carbon-laden mononuclear leukocytes in relation to the total leukocyte number was higher in the extravascular area of the laser sites than in the systemic circulation. These findings indicate that the majority of mononuclear leukocytes that accumulate at the sites of laser lesions are derived from the systemic circulation.  相似文献   
66.
Collaborative Practice provides a forum for healthcare professionals to share expertise and enhance communication.  相似文献   
67.
The objective of the study was to investigate the effects of oral appliance (OA) therapy on ambulatory blood pressure in patients with obstructive sleep apnea (OSA). Eleven OSA patients who received OA therapy were prospectively investigated. Ambulatory blood pressure was measured for 20 h from 4:00 p.m. to 12:00 noon the next day using an ambulatory blood pressure monitor. The Respiratory Disturbance Index (RDI) was measured in the pretreatment and posttitration periods. The OA was titrated to reach a therapeutic jaw position over 2 to 8 months, and posttitration measurements were repeated. At posttitration, the RDI was significantly decreased from a mean (SD) of 24.7 (20.1) to 6.1 (4.5). Significant reductions in diastolic blood pressure (DBP) and mean arterial pressure (MAP) were found for the 20-h periods, and systolic blood pressure (SBP), DBP, and MAP while asleep. The mean values were 79.5 (5.5) to 74.6 (6.0) for DBP and 95.9 (5.4) to 91.2 (5.9) for MAP, for over a 20-h period, and 118.4 (10.0) to 113.7 (9.1) for SBP, 71.6 (8.0) to 67.2 (7.9) for DBP, and 88.4 (8.0) to 83.9 (7.5) for MAP, while asleep. This study suggests that successful OSA treatment with an OA may also be beneficial to lower blood pressure in OSA patients, as previously suggested for nasal continuous positive airway pressure therapy. This study was conducted in the Division of Orthodontics, The University of British Columbia, Canada  相似文献   
68.
Hospitalized neonates are commonly colonized soon after birth with Staphylococcus aureus. The majority of neonates do not develop infectious sequelae; however, premature neonates appear to be more susceptible to serious infections, such as pneumonia. We report a case of an extremely low birth weight infant who developed necrotizing pneumonia due to methicillin-resistant Staphylococcal aureus (MRSA). The MRSA isolate from this neonate is identical to the strains that have been causing primarily community-associated skin and soft tissue infections. The severe course of this patient may be attributed to the presence of the Panton-Valentine leukocidin gene, a well-known virulence factor leading to soft tissue and pulmonary infections.  相似文献   
69.
70.
Stressful life events are commonly associated with the onset and maintenance of psychopathology and much research has focused on the role of the corticotropin-releasing factor (CRF) system in mediating psychopathology. Since CRF serves to integrate the stress response, it is possible that the CRF system plays a role as a neurochemical linkage between stress and psychopathology. CRF-binding protein (CRF-BP) is thought to modulate CRF activity by decreasing its actions. Therefore, in some psychopathological states, alterations in CRF-BP function may contribute to dysregulation of the CRF system. Since the amygdala CRF system mediates stress- and anxiety-related behaviors and alterations in amygdala function are associated with psychopathology, we examined amygdala CRF-BP gene expression in post-mortem brains from subjects with major depression, bipolar disorder, and schizophrenia as well as in controls. In addition to characterizing the anatomic distribution of CRF-BP mRNA in the human amygdala and medial temporal lobe region, we found a significant decrease in CRF-BP mRNA levels in the basolateral amygdala of male bipolar and male schizophrenic subjects and the lateral amygdala of male bipolar subjects. These results raise the possibility that men with decreased amygdala CRF-BP may be more vulnerable to the effects of stress exposure on the etiology or maintenance of bipolar disorder or schizophrenia.  相似文献   
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