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991.
Pantothenate kinase-associated neurodegeneration (PKAN) is a rare autosomal recessive disorder with onset in childhood and rapid progression. There is no causative and insufficient symptomatic drug therapy. Deep brain stimulation (DBS) of the internal pallidum (GPi) has been reported to improve motor function. Most case reports, however, are limited to short observational periods. The impact of DBS on the progression and life expectancy in PKAN is unknown. We present a 5-year outcome and video documentation of bilateral GPi-DBS of an adolescent patient suffering from genetically defined PKAN.  相似文献   
992.
993.
Symptoms of obstructive lung disease in domestic cleaners have been related to the use of bleach and other irritant cleaning products. The short-term effects of cleaning exposures on respiratory symptoms and peak expiratory flow (PEF) were investigated in domestic cleaners with respiratory disorders. In a panel study, 43 female domestic cleaners with a recent history of asthma and/or chronic bronchitis completed a 2-week diary, collecting information on respiratory symptoms, PEF and cleaning exposures. Mixed regression models were used to assess daily changes in symptoms and PEF associated with specific cleaning exposures. The probability of having work-related asthma was individually assessed by a computerised diagnostic system and an occupational asthma expert. Lower respiratory tract symptoms were more common on working days and were predominantly associated with exposure to diluted bleach, degreasing sprays/atomisers and air fresheners. Associations with upper respiratory tract symptoms and PEF were less apparent. Eleven (30%) subjects scored positively for work-related asthma. It is concluded that exposure to certain irritant cleaning products aggravates lower respiratory tract symptoms in female domestic cleaners with asthma or chronic bronchitis.  相似文献   
994.
995.
Thrombophilia may be defined as the tendency to arterial or venous thrombosis. Thrombophilia can be acquired or hereditary. Acquired conditions leading to arterial thrombosis are commonly encountered in vascular surgical practice, but less well known is the potential influence of genetic factors. In recent years, evidence has accumulated for a crucial role of genetic factors in the pathogenesis of venous thrombosis, many previously unknown genetic defects having been recently identified. The role of genetic predisposition for the pathogenesis of arterial occlusive disease on the other hand is unknown, although recent publications suggest a definite link. This may have implications for the vascular surgeon in the management of patients with arterial disease. A medline search was performed in order to identify papers published between 1990-2002 on thrombophilia, arterial disease and peripheral arterial occlusive disease (PAOD). With regard to venous thrombosis we obtained a much wider knowledge about genetic defects leading to thrombophilia. This has altered the diagnostic and therapeutic approach to patients with venous thrombosis, and has had an important influence on counselling and screening of family members, especially females of childbearing age. With regard to arterial thrombosis, certain thrombophilic disorders have a definite pathophysiological role. Hyperhomocysteinaemia, inherited or acquired, has been demonstrated to be an independent risk factor for athero-thrombosis. The antiphospholipid antibody syndrome (APS), an acquired condition, also predisposes to arterial thrombosis. Other thrombophilic conditions, such as prothrombin gene G20210A variant or factor V Leiden, have been investigated, but current evidence does not unequivocally support the hypothesis of a pathophysiological role in athero-thrombosis. Routine screening for thrombophilia in patients with athero-thrombosis is therefore not generally recommended on the basis of current evidence, but there is a role for selective screening.  相似文献   
996.
OBJECTIVE: To determine the efficacy of a new multilevel surgical protocol for obstructive sleep apnea (OSA). STUDY DESIGN AND SETTING: Sixty patients with moderate to severe OSA because of multilevel pharyngeal obstruction were enrolled into this prospective, controlled clinical trial after clinical examination, endoscopy, and polysomnography. Surgery included uvulaflap, tonsillectomy, hyoid suspension, and radiofrequency treatment of the tongue base (group A). A second group did not receive hyoid suspension (group B). In both groups, nasal surgery was performed if necessary. Polysomnography and Epworth Sleepines Scale (ESS) were recorded at baseline and 2 to 15 months after surgery. RESULTS: In group A, the mean apnea-hypopnea index (AHI) decreased significantly after surgery (38.9 +/- 20.0 vs 20.7 +/- 20.6, P < 0.0001), whereas in group B the AHI did not. All secondary variables (minimal oxygen saturation, mean oxygen saturation, arousal index), and the ESS significantly improved in group A with only changes in arousal index and ESS reaching levels of significance in group B. CONCLUSION: The presented protocol including the hyoid suspension proved to be effective in the treatment of OSA, whereas surgery without hyoid suspension was less successful. EBM rating: B-2b.  相似文献   
997.
998.
The structure-activity relationship between (E)-5-(2-bromovinyl)- and 5-vinyl-1-beta-D-arabinofuranosyluracil (BV-araU and V-araU) in inhibition of Epstein-Barr virus (EBV) was evaluated. Both V-araU and BV-araU effectively inhibited EBV replication in virus-producer P3HR-1(LS) cells, as determined by DNA-DNA hybridization. The 50% effective doses (ED50) for viral DNA replication were 0.005 and 0.3 microM for V-araU and BV-araU, respectively. The in vitro therapeutic index was 4000 for V-araU and 1300 for BV-araU. Synthesis of EBV-induced polypeptides with molecular weights of 145,000 (145, 140, 130, and 110 kDa) was significantly inhibited by both drugs. Only V-araU inhibited the synthesis of 85-, 55-, and 32-kDa polypeptides by approx. 50%. Kinetic analysis of inhibition and reversibility of EBV DNA replication after removal of the drugs indicated that BV-araU has a more prolonged inhibitory effect than V-araU. These results indicate that the substitution of H by Br in the 5-vinyl group results in marked reduction in anti-EBV activity while prolonging the drug effect and diminishing cytotoxicity.  相似文献   
999.
Genital papilloma virus infection (GPVI) is in many patients a longlasting, relapsing disease for which no effective treatment is available. This fact and the association between the virus and cancer puts much stress on the afflicted patient. Of 41 men with GPVI interviewed, 17 (40%) reported a negative effect of the disease on their sexual life. Most distressing was the fear of transmitting the disease to their partner. After 18 months, 15 (37%) of the 41 men still exhibited signs of GPVI. In the care of patients with GPVI, more attention needs to be paid to the psychosexual effects of the disease.  相似文献   
1000.
Results reported are for single dose exposures and refer to 60Co-gamma-irradiation. The RBE determined by V79 cell survival and based on the Do ratio was found to be 1.70 +/- 0.4 ranging from 1.5 to 1.8. In the case of the regeneration of mouse jejunal crypts the RBE was calculated at ten cell survival and was found to be 1.68. The maximum acute mouse skin reaction at a skin score of 2.0 was found to be 2.1 while the average skin reaction was 1.7. Growth retardation of Vicia faba bean roots measured at the level of 50% indicated an average RBE of 3.0 and a range of 2.7 to 3.7. The OER obtained for V79 cell survival was found to be 1.7 to 1.8. Comparison is made with the RBE and OER measurements for the neutron facilities at Clatterbridge, Fermilab and Louvain-la-Neuve which produce neutrons by the same nuclear reaction and whose physical specifications closely resemble those of the Faure neutrons. This comparison indicates that the Faure beam shows no unusual biological features and that its biological effectiveness is in line with that expected from its physical characteristics.  相似文献   
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