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61.
The expression of reelin mRNA was studied during embryonic brain development in the chick, by using in situ hybridization. Reelin was highly expressed in the olfactory bulb and in subpial neurons in the marginal zone of the cerebral cortex. In the diencephalon, the ventral division of lateral geniculate nuclei and perirotundal nuclei were strongly positive. High levels of expression were associated with some layers of the tectum and with the external granule cell layer of the cerebellum. A more moderate signal was detected in the septal nuclei, hyperstriatal fields, retina, habenular nuclei and hypothalamus, in some reticular nuclei of the mid- and hindbrain, and in the spinal cord. Little or no expression was observed in the cortical plate, Purkinje cells, or the inferior olivary complex. Comparison with reelin expression during mammalian and reptilian brain development reveals several evolutionarily conserved features that presumably define a homology. In addition, significant differences are noted, particularly in telencephalic fields. Most importantly, the developing chick cortex does not exhibit high levels of reelin expression in subpial Cajal-Retzius cells characteristic of the mammalian brain. These observations are compatible with an action of reelin on adhesion and/or of nucleokinesis at the level of target cells. They further suggest that, whereas the telencephalon of birds and archosaurs evolved primarily from dorsal ventricular ridge derivatives in which reelin is probably secondary, the increase in number of reelin-positive cells, and amplification of reelin expression played a key part in the evolution of the cortex in the synapsid lineage leading to mammals.  相似文献   
62.
Endoscopic frontal sinus surgery is still considered difficult, risky to perform, and likely to result in a high failure rate. We have previously reported on our technique of endoscopic frontal sinus surgery, stressing the importance of identification and preservation of natural outflow tract. Our study of frontal sinus anatomy shows that the mean frontal ostium anterior—posterior and transverse dimensions are 7.22 ± 2.78 mm and 8.92 ± 2.95 mm, respectively; therefore, dissection of obstructive structures in frontal recess leads to a wide opening of frontal sinus outflow. A key surgical landmark in our technique is the superior attachment of the uncinate process. This article provides an update of the surgical anatomy of the frontal recess region and our surgical technique, as well as a discussion of our approach to frontal sinus revision surgery.  相似文献   
63.
A case of a child with bilateral fleshy limbal masses with a coloboma of the right upper lid is discussed. Systemic examination revealed two patches of alopecia on the right frontoparietal and right occipital areas of the scalp. Punch biopsy and histopathological examination led to the diagnosis of Linear Nevus Sebaceus Syndrome (LNSS) with bilateral complex limbal choristomas. The authors have stated that they do not have a significant financial interest or other relatioship with any product manufacturer or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes unlabeled, unapproved, or investigative products or devices.  相似文献   
64.
PURPOSE: Idiopathic detrusor overactivity has not been thoroughly investigated and its natural history remains largely anecdotal. Bladder overactivity resulting from a neurogenic, anatomical or medical condition has been well described. Therefore, we assessed the long-term results of conservative treatment of children with idiopathic symptomatic refractory detrusor instability. MATERIALS AND METHODS: We reviewed the records of 58 patients who had an isolated finding of uninhibited contractions on urodynamics performed for refractory enuresis and daytime wetting between 1988 and 1994. Study exclusion criteria were chronic urinary tract infection, neurological lesion, anatomical abnormality of the lower urinary tract and less than 12 months of followup. RESULTS: Of the 30 children who met our study inclusion criteria 26 (87%) had complete (21) or significant (5) symptom resolution. Average time to resolution was 2.7 years (range 0.2 to 6.6). Patients with a 50% to 90% bladder capacity expected for age were more likely to benefit from therapy than those with a bladder capacity outside of this range. Age and gender were not significant predictors of resolution although girls were more likely to have resolution than boys. CONCLUSIONS: Idiopathic detrusor instability is amenable to conservative management in the majority of patients during a prolonged period. We advocate thorough urological and urodynamic evaluation to identify idiopathic detrusor instability as an etiology of enuresis and daytime wetting in complicated cases.  相似文献   
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Of 468 diagnosis-related groups identified by the federal government for Medicaid reimbursement, 15 are related to obstetric hospital care. Each diagnosis-related group is considered a distinct group in which cases are homogeneous with respect to resource consumption. Because the diagnosis-related group system is based primarily on data from community and secondary care hospitals, it does not differentiate sufficiently among high-risk obstetric patients seen at tertiary care institutions, such as Florida's Regional Perinatal Intensive Care Centers. We developed an alternative scheme for diagnosis-related groups, called obstetric care groups, using the federal diagnosis-related groups as the model from which to depart. Data collected for 4192 women during a 2 1/2-year period indicate that obstetric care groups provide more homogeneous groups than diagnosis-related groups for our population of high-risk patients. The obstetric care groups differentiate between no complications, one complication, and two or more complications, while the diagnosis-related groups differentiate only between no complications and one or more complications. Also, complications for obstetric care groups are based on only 19 diagnoses that contribute significantly to resource consumption, while the list of possible complications exceeds 200 for diagnosis-related groups. Although the obstetric care group classification system is simpler than that for diagnosis-related groups, it results in a more accurate reimbursement of hospitalization charges for high-risk obstetric care.  相似文献   
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68.
ObjectiveTo investigate the incidence of cardiac arrhythmias at six months following traumatic spinal cord injury (SCI) and to compare the prevalence of arrhythmias between participants with cervical and thoracic SCI.DesignA prospective observational study using continuous twenty-four-hour Holter monitoring.SettingInpatient rehabilitation unit of a university research hospital and patient home setting.ParticipantsFifty-five participants with acute traumatic SCI were prospectively included. For each participant, the SCI was characterized according to the International Standards for Neurological Classification of SCI by the neurological level and severity according to the American Spinal Injury Association Impairment Scale.Outcome measuresComparisons between demographic characteristics and arrhythmogenic occurrences as early as possible after SCI (4 ± 2 days) followed by 1, 2, 3, 4 weeks and 6 month time points of Holter monitoring.ResultsBradycardia (heart rate [HR] <50 bpm) was present in 29% and 33% of the participants with cervical (C1–C8) and thoracic (T1–T12) SCI six months after SCI, respectively. The differences in episodes of bradycardia between the two groups were not significant (P < 0.54). The mean maximum HR increased significantly from 4 weeks to 6 months post-SCI (P < 0.001), however mean minimum and maximum HR were not significantly different between the groups at the six-month time point. There were no differences in many arrhythmias between recording periods or between groups at six months.ConclusionsAt the six-month timepoint following traumatic SCI, there were no significant differences in occurrences of arrhythmias between participants with cervical and thoracic SCI compared to the findings observed in the first month following SCI.  相似文献   
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本文采用描述政治过程的方法,比较全面地回顾了澳大利亚全民医疗保险的缘起,并特别关注系统建立和完善过程中政治因素的影响和对中国同行的启示。全民医疗保险制度是一个具有鲜明政治特征的社会政策,它是人权运动和社会公平思想与传统的经济学和市场理论相互较量的结果。全民医疗保险正在成为中国学术界和政界的一个重要议题,是提高卫生服务的公平性和可及性,建立和谐社会的重要方面。澳大利亚建立全民医疗保险的故事,可以让我们开阔视野和深入思考。  相似文献   
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