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91.
The effects of streptozotocin-induced diabetes on the retinal dopaminergic system have been examined in Long-Evans (pigmented) rats. Tyrosine hydroxylase activity was significantly decreased while dopamine-stimulated adenylate cyclase was increased in 2-month-diabetic rats. The observed increase in dopamine-stimulated adenylate cyclase activity in diabetic retinae may be related to neurotransmitter receptor changes because postreceptor activation of adenylate cyclase by guanylyl imidodiphosphate was not altered.  相似文献   
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A 16-year-old boy presented with diminished visual acuity of 6/60 following blunt trauma to his right eye with a cricket ball. Fundus examination showed commotio retinae. Optical coherence tomography (OCT) demonstrated increased reflectivity with small optically clear spaces in the area corresponding to the photoreceptor outer segment. At 2-month follow up the visual acuity improved to 6/6. A small area of retinal opacification persisted nasally, and OCT of the corresponding area continued to show increased reflectivity in the area of photoreceptor outer segment. Increased reflectivity on OCT in eyes with commotio retinae probably denotes photoreceptor outer segment disruption and seems to be reversible to a variable extent.  相似文献   
95.

Purpose

The aim of this study was to determine the outcome of antenatally diagnosed exomphalos.

Methods

The database of a tertiary referral Fetal Medicine Centre was searched for all cases of antenatally diagnosed exomphalos between January 1991 and December 2002. Patients, general practitioners, and hospitals were contacted for outcome details.

Results

In total, 445 cases of exomphalos were identified. In 250 (56%) cases, the fetal karyotype was abnormal (group A), in 135 (30%) cases, the karyotype was normal (group B), and in 60 (14%) cases, karyotyping was declined (group C). In group A, there were 248 (99%) terminations of pregnancy (TOP) or fetal deaths and 2 live births. In group B, 74 (54%) fetuses had other structural anomalies; 82 (61%) pregnancies resulted in TOP or fetal death, 42 (31%) in live births, and 11 (8%) were lost to follow-up. In group C, 38 (63%) fetuses had other structural anomalies; 41 (69%) pregnancies resulted in TOP or fetal death, 11 (18%) in live births, and 8 (13%) were lost to follow-up. Of the 55 live births, 11 died preoperatively and 44 had surgery. There were no postoperative deaths.

Conclusions

Less than 10% of the antenatal diagnostic workload reached operative repair. In our unit, these babies are a highly selected group, which is a factor in the high postoperative survival.  相似文献   
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Summary Most central neurocytomas (CN) and spinal neurocytomas (SN) have a bland well-differentiated histologic picture and uneventful clinical course. However, rare examples showing histologic atypia, recurrence and even CSF dissemination have been reported. Herein we report a case of recurrent spinal neurocytoma in a 24-year-old male who presented with a 2-month history of weakness and numbness of the left upper and lower limbs, and was previously operated at the same site 10 months ago. MRI revealed a contrast enhancing intramedullary mass involving C5-T1 region. Radiologic and operative impression at both surgeries was that of a glioma, possibly anaplastic. Histologic and immunohistochemical features in both resections were those of an atypical neurocytoma. The tumor showed rare mitoses, focal mild vascular proliferation in both specimens, and necrosis in the initial specimen. MIB1 labeling indices were 9 and 10%, respectively. Based on the analysis of this case and limited data from the literature, it is hypothesized that SN shows a histopathologic picture, immunoprofile and biologic behavior very similar to CN. However, the presence of histologic atypia and increased MIB1 index in SN appear to more closely correlate with tumor recurrence and a worse overall outcome, in part due to their location in the critical region of cervical spinal cord. Therefore, we hypothesize that SN with atypia requires a close clinical follow up. As in CN, radiation therapy is perhaps best reserved for atypical, progressive and recurrent SN.  相似文献   
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We report a rare case of type IV jejunal atresia with enteric duplication and multiple diverticuli, found in a 3-day-old baby girl. To our knowledge, this association has never been reported before.  相似文献   
100.
Various types of neurological manifestations are described in dengue fever, of which peripheral neuropathy is rarely reported. We are reporting such a case that presented with three days' history of fever and weakness of all the four limbs of two days' duration. On investigations it turned out to be acute motor sensory axonal neuropathy (AMSAN) type of Guillain-Barre syndrome with decrease platelet counts and positive serology for dengue. All other causes of acute polyneuropathy were ruled out by history and relevant investigations. Patient improved with intravenous immunoglobulin and other supportive therapy.  相似文献   
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