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111.
A 27-month-old girl suffered from severe sensory neuropathy with minimal motor dysfunction. The CSF protein level was increased and nerve conduction was severely impaired. Sural nerve biopsy specimen showed increased endoneurial connective tissue. An onion-bulb pattern with concentric interdigitations of Schwann cell cytoplasmic processes and redunbant basal laminae were prominent features under electron microscopy. Degress of myelination in individual fiber was far less than expected. Although the clinical manifestations of onion-bulb neuropathy with onset in infancy have been reported to resemble infantile progressive spinal muscular atrophy, the present case demonstrates that the condition can also appear as severe sensory ataxia.  相似文献   
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Although small cell lung cancer (SCLC) is very chemosensitive, cerebral metastases are treated with radiotherapy in the belief that they are protected from chemotherapy by the blood-brain barrier (BBB). The validity of this assumption has not been tested in clinical practice. In a randomised trial of treatment in 610 patients with SCLC, 19 patients who had symptomatic cerebral metastases at presentation were treated initially with chemotherapy, and cranial irradiation withheld. Chemotherapy was cyclophosphamide 1 g m-2 i.v. day 1, vincristine 2 mg i.v. day 1 and etoposide 100 mg tds p.o. days 1-3, repeated every 21 days, with response assessed objectively by computerised tomography (CT) or radionuclide brain scan, and by clinical examination. A post-chemotherapy scan was obtained in 14 patients, eight of whom achieved a partial remission and one a complete remission of the cerebral metastases. The radiologically proven responses were sustained and accompanied by rapid neurological improvement. Of the remaining five patients who were assessed by clinical examination alone, one had improved neurological function after chemotherapy. The response rate for SCLC cerebral metastases treated with chemotherapy was therefore 10/19 (53%). Chemotherapy has the advantage over cranial irradiation of simultaneously treating both cerebral metastases and extracranial disease. The place of chemotherapy in the management of cerebral metastases in this and other chemosensitive tumours should be reconsidered since these findings indicate that the BBB does not prevent response to chemotherapy.  相似文献   
114.
Diagnosis and pitfalls in the treatment of parotid tumors   总被引:1,自引:0,他引:1  
Any swelling near the ear is best considered a parotid neoplasm until proved otherwise. The diagnosis is primarily based on the clinical examination. Imaging studies are best reserved for patients who present with palate or tonsil swellings, which must be distinguished from parapharyngeal or minor salivary gland tumors. Almost all benign, and most malignant parotid tumors can be resected with preservation of the facial nerve. Aspiration biopsy can add useful information, but is not essential for treatment planning as the extent of the surgical procedure is primarily determined by the extent of the tumor. Survival rates in patients with malignant tumors are most significantly influenced by tumor stage. Results seem to have improved in recent years, possibly because we are treating a larger proportion with favorable lesions. Another factor may relate to the enhancement of locoregional control now achieved with postoperative radiotherapy, particularly in patients with Stage III or IV tumors.  相似文献   
115.
Who are the old? Is age a category, like sex? Does just getting to a certain age justify certain rewards and certain limits? Is there a role for old physicians working in a hospital? What should age be a criterion for? There are no firm answers, but there should be more discussion.  相似文献   
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H Shimomura  R G Spiro 《Diabetes》1987,36(3):374-381
Treatment of human glomerular basement membrane (GBM) with 4 M guanidine HCl resulted in a preferential extraction of noncollagenous components including laminin, fibronectin, entactin, and heparan sulfate proteoglycan, whereas effective solubilization of type IV collagen required exposure to denaturing solvents in the presence of reducing agents. The guanidine HCl-solubilized constituents were identified by immunochemical procedures after resolution by polyacrylamide gel electrophoresis, CL-6B filtration, and DEAE-cellulose chromatography. Two immunologically related heparan sulfate proteoglycans (Mr approximately 350,000 and 210,000) were observed by electrophoresis, with the higher-molecular-weight form being predominant. An examination of the two proteoglycans after heparitinase digestion or chemical deglycosylation indicated that heparan sulfate chains and other carbohydrate units are attached to core proteins with Mr approximately 140,000 and 110,000, respectively. Radioimmunoassays indicated that human diabetic GBM contained significantly lower (P less than .005) amounts of heparan sulfate proteoglycan and laminin with average values that were 30 and 60%, respectively, of nondiabetic controls; the fibronectin content of the diabetic GBM, however, was not significantly different from the normal. These findings, together with previous studies showing increases in GBM collagen, indicate that an alteration in the macromolecular architecture of this basement membrane occurs in diabetes that may be responsible for the filtration defect and the ultimate glomerular occlusion.  相似文献   
119.
We studied 12 newborn infants (gestational ages 26-39 wk [mean +/- SD, 30.6 +/- 4.7]; birth weight 640-2700 g, [mean, 1,322 +/- 688]; postnatal age 1-24 days [mean, 9.6 +/- 8.5]) who received clindamycin phosphate for suspected or proven necrotizing enterocolitis (ten patients) or suspected anaerobic septicemia (two patients) in doses of 3.2-11 mg/kg every six hours. Range of mean serum concentration of clindamycin at steady state was between 12.7 and 40 micrograms/ml (therapeutic range = 2-10 micrograms/ml). High concentrations could be attributed to elimination T1/2 (6.3 +/- 2.1 hr) 100% longer than in older children or adults. Clindamycin clearance (61.6 +/- 31.6 hr ml/kg/hr) was lower than in older children or adults. Because of the observed prolongation in T1/2 and correspondingly lower clearance, the IV dose of clindamycin in newborn infants should be reduced to 15-20 mg/kg/day given in four daily doses.  相似文献   
120.

Background  

To assess the feasibility of the sentinel lymph node procedure in patients with rectal cancer extending to the anal canal.  相似文献   
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