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81.
82.
A 50 year old woman presented with a subacute onset of vertigo and diplopia followed by an encephalopathy with confusion, spasticity, ataxia, myoclonus, and multiple branch retinal arteriolar occlusions and unilateral sensorineural deafness. Brain biopsy confirmed multiple microinfarcts with no vasculitis. After the procedure she had a right iliofemoral deep vein thrombosis and was found to be heterozygous for the factor V Leiden mutation. She was treated with anticoagulants and made a marked recovery with no relapses 6 months after presentation. This case extends the age range at which Susac's syndrome can present, and raises the possibility that the condition may be associated with abnormalities of coagulation.  相似文献   
83.
The Effect of Estrogen Deficiency on Calcium Balance in Mature Rats   总被引:5,自引:0,他引:5  
The role of estrogen in the regulation of calcium balance is still poorly understood. A calcium balance study was performed to examine the effects of estrogen status in relation to fecal calcium loss as a component of bone loss after oophorectomy (OOX) in the mature rat. The components of the classic calcium balance were compared with calcium balance estimates obtained from whole body bone density. Six month or older Sprague Dawley rats were allocated to either a sham-operated or OOX group and fed a 0.1% calcium diet. The bone mineral density (BMD) and bone mineral content (BMC) were measured at baseline, 6 weeks, and 9 weeks. A calcium balance was done for 6 days before and 6 weeks post OOX. The fall in BMD from baseline to 9 weeks in the OOX group was significantly greater than in the sham-operated group. The calcium balance was more negative at baseline than at 6 weeks in both groups of animals because they had not adapted to the low calcium diet. However, the increase in calcium balance was significantly less in the OOX animals than in the sham-operated animals. The greater the rise in calcium balance from the baseline to the 6 weeks balance the less the fall in the calcium content of the whole body (Spearman correlation: r = 0.604 P = 0.008). The fall in fecal calcium, but not urine calcium or calcium consumed, was negatively correlated with the change in whole body BMC (Spearman correlation: fecal calcium r =−0.763 P = 0.001). Thus, the primary effect of estrogen deficiency on calcium balance in the mature rat appears to be calcium flux in the bowel, rather than renal calcium handling. Received: 16 April 1997 / Accepted: 22 September 1998  相似文献   
84.
Eight patients (average age, 10 years) had a unilateral forearm lengthening procedure using the technique developed by Ilizarov. The procedure was performed in 4 patients with radial agenesis, in 2 with multiple hereditary exostosis, in 1 with ulnar agenesis, and in 1 with multiple enchondromatosis. Patients underwent distraction osteogenesis through either a unifocal or bifocal corticotomy. Forearm length increased on average 6.0 cm (range, 3.6-8.1 cm) or 54% (range, 21% to 94%) with a lengthening index of 1.3 months per centimeter (range, 0.6-1.9 months per centimeter). The length of follow-up averaged 4.5 years and involved office examinations with task evaluation and a questionnaire addressing function and appearance. Limb length discrepancy at follow-up measured 3.7 cm (range, 0.0-8.0 cm). Lengthening of the forearm was found to improve upper extremity function; it allowed the patient to reach distant body parts and to perform select activities requiring near-equal arm length. Forearm lengthening also improved the appearance of the arm if adequate soft tissue was preserved. Full restoration of arm length was not a requirement for a successful outcome and patient satisfaction with the results of the procedure was high.  相似文献   
85.
Retinal vascular occlusion and deficiencies in the protein C pathway.   总被引:3,自引:0,他引:3  
PURPOSE: To report abnormalities in the protein C pathway and other vascular occlusion risk factors in patients with retinal vascular occlusion. METHODS: In a study, we investigated 76 consecutive patients who had in-patient evaluation of venous or arterial retinal vascular occlusion. All patients underwent comprehensive tests for coagulation disorders including determinations of protein C, protein S, lupus anticoagulants, and resistance to activated protein C and were screened for vascular disease risk factors. Resistance to activated protein C was confirmed by a polymerase chain reaction method to detect the specific factor V R506Q mutation. For comparative purposes, we also screened 209 consecutive inpatients with deep vein thrombosis from the same geographic region for resistance to activated protein C as well as protein C and protein S deficiencies. RESULTS: Ten (29%) of 35 patients with central retinal vein occlusion (CRVO) had factor V R506Q mutation. The factor V R506Q mutation was detected in four (19%) of 21 patients with branch retinal vein occlusion. The higher frequency in factor V R506Q mutation compared with the expected 9% mutation prevalence in a white population was highly significant for the central retinal vein occlusion group but not for the branch retinal vein occlusion group. In all patients with resistance to activated protein C, the factor V R506Q mutation was detected; 16 were heterozygous, one homozygous. No cases of lupus anticoagulants, protein C, or protein S deficiencies were detected. Forty (19%) of 209 patients with deep vein thrombosis were carriers of the factor V R506Q mutation. CONCLUSIONS: The prevalence of the factor V R506Q mutation is similar in patients with central retinal vein occlusion and patients with deep vein thrombosis and represents a relevant risk factor. Screening for this mutation is therefore recommended in all patients with central retinal vein occlusion.  相似文献   
86.
87.
Automatic decomposition electromyography (ADEMG) is a commercially available software package with installed reference values that enables the objective measurement of motor unit action potentials (MUAPs). To assess the diagnostic yield of this package in idiopathic inflammatory myopathies (IIM) we performed biceps brachii ADEMG in 17 patients with polymyositis, dermatomyositis and inclusion body myositis. Results were compared with those in 12 controls, and with the results of conventional EMG of the biceps and other muscles. Decreased mean values for MUAP duration occurred significantly more frequently in IIM patients than in controls; other MUAP characteristics did not differ. In IIM patients, decreased mean amplitude and increased mean number of turns occurred significantly less frequently on ADEMG than did corresponding abnormalities on conventional biceps EMG. Decreased mean values for duration and amplitude, and increased mean values for number of turns were seen significantly less often on ADEMG than corresponding abnormalities on conventional EMG of four different, individually chosen muscles. Overall evaluation of ADEMG resulted in a diagnosis of possible myopathy in 1 and probable myopathy in 8 patients, whereas overall evaluation of conventional EMG led to a diagnosis suggestive of IIM in 13 patients. We conclude that, although measurement of mean MUAP duration might be valuable in IIM diagnosis, our results do not favour the use of biceps brachii ADEMG and the installed reference values for the diagnosis of IIM. We suggest modifications to improve ADEMG's applicability.  相似文献   
88.
Inquest on QUEST     
Describes how a group of nurse managers developed a tool for measuring the quality of care in mental hospital wards and how this was adapted for use within general elderly services. Examines the impact of the tool on service provision within a group of small local community hospitals and evaluates it using a matrix composed of Donabedian's structure/process/outcome model of quality and Maxwell's six dimensions of quality.  相似文献   
89.
90.
J O Armitage  F R Dick  M P Corder 《Cancer》1978,41(2):422-427
Nine patients with chronic lymphocytic leukemia (CLL) who also developed diffuse histiocytic lymphoma (DH) are described. The incidence of patients with CLL developing DH was at least 3.3%. CLL existed for a median of 2 years before the diagnosis of DH. DH presented in 8 patients with abdominal symptoms and/or enlarging lymph nodes, spleen and liver. There were no consistent laboratory abnormalities associated with the onset of DH. In 4 of the patients the DH appeared to be localized. Eight of the 9 patients have died with a median survival of 2 months from the diagnosis of DH. Whether DH occurs as a result of "blastic transformation" of pre-existing CLL or is a second, unrelated malignancy is not certain. It is hypothesized that utilizing current therapies for DH might favorably influence survival.  相似文献   
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