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61.
Phenotype of patients with the aprataxin gene mutation varies and according to previous studies, screening of aprataxin gene could be useful, once frataxin gene mutation is excluded in patients with normal GAA expansion in frataxin gene. In the present study, we sought to determine possible causative mutations in aprataxin gene (all exons and flanking intronic sequences) in 14 Greek patients with sporadic cerebellar ataxia all but one without GAA expansion in frataxin gene (1 patient was heterozygous). No detectable point mutation or deletion was found in the aprataxin gene of all the patients. Our results do not confirm the previous studies. This difference may be attributed to the different populations studied and possible different genetic background. It is still questionable whether the screening for aprataxin mutation in Greek patients’ Friedreich ataxia phenotype is of clinical importance; larger, multicenter studies are necessary to clarify this issue.  相似文献   
62.
Surgery of the stapes may cause a number of complications, including hearing deficits and balance disorders. This has made it necessary to look for improved techniques. Small-fenestra stapedotomy has recently been popularized. Lasers have been advocated for use in fenestrating the stapes footplate. On the other hand, sculpting the middle ear ossicles during tympanoplasty is often necessary for the reconstruction of the ossicular chain and the improvement of sound conduction. Using an excimer laser with a wavelength of 193 nm, fenestrations of the footplate and ossicular sculpting were performed on ossicles obtained during ear surgery and from human cadaver temporal bones. The results indicate that the excimer laser can be used effectively and accurately on an experimental basis and that further research is needed before this method can be used for clinical purposes.  相似文献   
63.
Appearance of PIVKA-II (protein induced by vitamin K absence-II) in serum is a biochemical sign of insufficient vitamin K-dependent carboxylation of prothrombin. Plasma concentrations of PIVKA-II and vitamin K1 were determined in 24 children with cystic fibrosis. Eight were supplemented with vitamin K1. The purpose of the study was to determine the occurrence of vitamin K deficiency in cystic fibrosis and to evaluate the effect of vitamin K supplementation. PIVKA-II was detectable in only one unsupplemented child. In this patient, the concentration of vitamin K1 was below the limit of detection of 60 ng/l. Vitamin K1 levels in the other unsupplemented children were normal (mean 476 ng/l = 1 mmol/l). The supplemented patients showed extremely high levels of vitamin K1 (mean 22445 ng/l = 50 nmol/l). In conclusion, vitamin K deficiency occurs infrequently in cystic fibrosis. Checking the coagulation system is advised, but routine vitamin K supplementation is not recommended. If additional vitamin K is needed, the starting dose should not exceed 1 mg daily.  相似文献   
64.
Fragile X syndrome is the most common inherited cause of mental retardation. Early diagnosis is important not only for appropriate management of individuals but also to identify carriers who are unaware of their high risk of having an affected child. The disorder is associated with a cytogenetically visible fragile site (FRAXA) at Xq27.3, caused by amplification of a (CGG)n repeat sequence within the gene at this locus designated FMR1. Clinical and molecular studies have been undertaken to screen for fragile X syndrome in 154 children with moderate and severe learning difficulties of previously unknown origin. Southern blot analysis of peripheral blood showed the characteristic abnormally large (CGG)n repeat sequence associated with fragile X syndrome in four of the 154 children. The findings were confirmed by cytogenetic observation of the fragile site and by further molecular studies. The families of the affected children were offered genetic counselling and DNA tests to determine their carrier status. These findings show that there are still unrecognised cases of fragile X syndrome. Given the difficulty of making a clinical diagnosis and the implications for families when the diagnosis is missed, screening in high risk populations may be justified. The issues involved in screening all children in special schools for fragile X syndrome are discussed.  相似文献   
65.
This review paper discusses potential relationships between Cholesterol levels, the therapeutic use of Statins and the risk of Alzheimer s Disease. Comparisons have also been made between the Western populations and Oriental populations. Epidemiological studies have shown that statins, which reduce the levels of plasma cholesterol by inhibiting the enzyme 3 hydroxy-3methylglutaryl-coenzyme A (HMGCoA) reductase, reduce the risk of Alzheimer s disease by up to 70%. Further research is required to determine whether cholesterol levels have a direct, causative, or indirect relationship with Alzheimer disease. Also, it is not clear why some statins reduce the prevalence of AD and others do not. Statins may have an affect on other AD risk factors, or act by mechanisms which are independent of their effects on cholesterol levels?  相似文献   
66.
67.
OBJECTIVE: To study the effectiveness of the MSC cold cap system to prevent chemotherapy-induced alopecia. METHODS: The system was applied in 83 cancer patients (mean age 49.8 years) undergoing chemotherapy with alopecia-causing agents. Seven patients did not tolerate the system. Seventy-six patients were evaluable for assessment; 26 received anthracycline (group A), 33 taxane (group T), 5 anthracycline plus taxane (group AT), 7 intravenous etoposide (group E) and 5 ifosfamide with or without other alopecia-causing drugs (group I). In group A, 18 patients received conventional (subgroup Ac) and 8 high doses (subgroup Ah). In group T, 8 patients received docetaxel (subgroup D) and 25 paclitaxel (subgroup P). Alopecia grade 0-1 (Dean's system) was considered as treatment success. RESULTS: Grade 0-1 alopecia was achieved in 49/76 (64.5%) patients: group T 23/33 (69.6%), subgroup P 16/25 (64%) and subgroup D 7/8 (87.5%); group A 18/26 (69.2%), subgroup Ac 16/18 (88.8%) and subgroup Ah 2/8 (25%); group AT 1/5 (20%); group E 6/7 (85.7%), and group I 1/5 (20%). CONCLUSIONS: The MSC cold cap system is effective in preventing alopecia from anthracycline, etoposide or taxane but not from anthracycline-taxane combinations or ifosfamide-containing regimens.  相似文献   
68.
Vitamin B(12) and folate deficiency is often associated with affective disorders mainly of the depressive type. We report a case of a 42-year-old woman with a mood disorder with mixed depressed/manic features that was due to vitamin B(12) and folate deficiency. The psychopathology developed over a five-year period without hematologic or other overt clinical characteristics of pernicious anemia. Replacement treatment with vitamin B(12) and folate was rapidly followed by full clinical remission, electroencephalographic normalization and neuropsychological improvement. At a one-year follow-up this condition was stable. Consequently, patients who respond poorly to psychopharmacologic treatment and/or present with atypical mood symptoms would warrant determination of vitamin B(12) and folate serum levels.  相似文献   
69.
Distal hereditary motor neuronopathies (dHMNs) form a heterogeneous group of rare disorders characterized by distal weakness and wasting in the limbs with no significant sensory involvement. Harding has classified dHMNs into seven categories based on clinical and genetic criteria. We report a novel form of autosomal recessive dHMN in 7 consanguineous families located in the Jerash region of Jordan. Onset of the disease is between 6 and 10 years of age and is characterized by weakness and atrophy of the lower limbs associated with pyramidal features. Within 2 years, symptoms progress to the upper limbs. Neurophysiological studies typically show normal conduction velocities, reduced compound motor action potential amplitudes, normal sensory nerve action potentials, and chronic neurogenic changes on needle electromyography. No significant abnormalities are seen on sural nerve biopsy. We call this novel form of dHMN Jerash hereditary motor neuronopathy. We studied the families at the molecular genetic level and mapped the Jerash hereditary motor neuronopathy gene to an approximately 0.54-cM region on chromosome 9p21.1-p12, flanked by microsatellite polymorphic marker loci D9S1845 and D9S1791. A maximum LOD score of 19.80 at theta = 0.001 was obtained between the disease and locus D9S1878.  相似文献   
70.
BACKGROUND: To determine the activity and safety of the combination of paclitaxel and pegylated liposomal doxorubicin (Caelyx) in patients with locally advanced breast cancer. PATIENTS AND METHODS: This was a multicenter phase II study. Thirty-five newly diagnosed patients with locally advanced breast cancer were included in the study. Histological or cytological diagnosis was necessary for inclusion. Median age was 54 years (range 26-73 years). Fifteen patients were premenopausal and 20 postmenopausal. Paclitaxel was administered at a dose of 175 mg/m(2) and pegylated liposomal doxorubicin 35 mg/m(2) every 3 weeks for six cycles. RESULTS: Twenty-five patients (71%) responded. Six (17%) had a complete response, 19 (54%) had a partial response, four remained stable, two progressed and four were not evaluated for response due to discontinuation of chemotherapy. Three patients had a pathologically complete response. A total of 173 cycles were administered. The primary toxicity observed was skin toxicity. Grade 3 skin toxicity was noted in four patients (11%). Palmar-plantar erythrodysesthesia (PPE) grade 3 was experienced by three (9%). Two patients presented with PPE and skin toxicity. Hematological toxicities included grade 3 leukopenia in four patients (3%). Other grade 3 toxicities were uncommon and included only alopecia in 29 patients (83%). Grade 3 or 4 neurotoxicity was not observed in any patient. Dose reduction was necessary in seven patients; in six due to skin toxicity and in one due to neutropenia. Four patients discontinued treatment due to skin toxicity. There were no treatment-related deaths. CONCLUSIONS: The combination of pegylated liposomal doxorubicin and paclitaxel was active in locally advanced breast cancer. The primary toxicity was cutaneous toxicity and it was manageable.  相似文献   
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