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81.
Background Delayed facial palsy ( DFP) after microvascular decompression ( MVD) in patients with hemifacial spasm ( HFS) is not uncommon,but the cause remains unknown. Objectives To assess whether intraoperative electromyography ( EMG) and brainstem auditory evoked potential ( BAEP) can predict DFP after MVD. Methods Between September 2009 and February 2011 we examined 86 patients,9 of whom ( 10. 4% ) developed DFP after MVD on the same side. All patients underwent MVD and were followed - up for a median period of 13 months ( range 6-22) . We retrospectively examined intraoperative facial EMG and BAEP findings using our MVD patients’ registry. We excluded secondary HFS and immediate postoperative facial palsy after MVD in this study. We assessed the prevalence and clinical characteristics of DFP and compared EMG and BAEP findings between DFP and non-DFP groups. Results: All pa- tients recovered completely,with a mean time to recovery of 37. 8 days ( range 22-57) . There were no significant differences between DFP and non - DFP patients in terms of the amplitude and latency of intraoperative EMG and BAEP. Conclusion The usefulness of intraoperative facial EMG and BAEP is limited and cannot predict DFP after MVD for HFS. We speculate that DFP after MVD is not associated with permanent nerve damage according to the EMG findings.  相似文献   
82.

Objective

To evaluate the antidiarrhoeal property of methanol extract of the leaves of Rauwolfia serpentina (R. serpentina) in experimental diarrhoea induced by castor oil in mice.

Methods

Doses of 100, 200 and 400 mg/kg R. serpentina leaf methanol extracts were administered to castor oil induced diarrhoea mice to determine its antidiarrhoeal activity.

Results

All doses of the extract and the reference drug atropine sulphate (3 mg/kg, i.p.) produced a dose-dependent reduction in intestinal weight and fluid volume. The extracts also significantly reduced the intestinal transit in charcoal meal test when compared to diphenoxylate Hcl (5 mg/kg, p.o.).

Conclusions

The results show that the extract of R. serpentina leaves has a significant antidiarrhoeal activity and supports its traditional uses in herbal medicine.  相似文献   
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84.
Suicide genes have recently emerged as an attractive alternative therapy for the treatment of various types of intractable cancers.The efficacy of suicide gene therapy relies on efficient gene delivery to target tissues and the localized concentration of final geneproducts.  相似文献   
85.
Mesenchymal hamartoma of the liver: radiologic-pathologic correlation   总被引:2,自引:0,他引:2  
Mesenchymal hamartoma of the liver (MHL) is an uncommon cystic mass of infancy that is a developmental anomaly rather than a neoplasm. Fourteen cases of MHL were retrospectively reviewed. Grossly, MHL is a solitary mass with cystic spaces of variable size. Patients are seen initially with painless progressive abdominal enlargement. On plain films, MHL appears as a large, noncalcified mass in the right upper quadrant. Scintigraphy is helpful in confirming its hepatic origin. Ultrasonography and computed tomography demonstrate a large multiloculated mass with considerable variation in the size of septa and cystic spaces. Angiographically, MHL is avascular or hypovascular. Recognition of these radiographic findings allows a correct diagnosis to be made in many cases. With resection, the prognosis is excellent.  相似文献   
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SUMMARY This study aimed to assess and compare the impact of letter of invitation, initial breast screening mammography, and subsequent recall procedures on the level of anxiety over breast problems. The survey of females undergoing routine breast screening procedures in a primary care setting is part of the first wave of a national breast screening programme in the UK. Women aged 50-64 registered with six general practices (n=2618) were invited by letter to attend for screening. Their self-perceived impact of receipt of invitation letter, attendance at initial screening, and recall, in terms of anxiety and concern about breast problems, was measured by a self-report questionnaire and the physical, emotional and social dysfunction subscales of the Psychological Consequences of Screening Mammography Questionnaire (PCQ). Overall, subjects' anxiety levels diminished between the receipt of their invitation letter and the completion of their screening examination. Subjects did not, however, respond to the letter of invitation and screening procedure in a homogeneous manner. In a sample of 1253, the letter of invitation reduced anxiety about breast problems in 39.7%, increased anxiety in 24.6%, and had no appreciable effect in 35.7%. In the 1280 who attended for breast screening, the examination procedure reduced anxiety about breast problems in 55.9%, increased anxiety in 12.8%, and had no appreciable effect in 31.3%. In a smaller sample (n=33) who completed questionnaires at recall, there were significant increases in PCQ-measured anxiety. Throughout the study, the PCQ was sensitive to change in anxiety over breast problems. We conclude that screening procedures can either increase or reduce anxiety about breast problems, or have no appreciable effect. Subjects' perception of the impact of receiving the letter of invitation and undergoing the screening examination procedure is related to previous levels of concern over breast problems. Conclusions about the psychological effect of breast screening cannot be drawn without consideration of the time and place of the baseline assessment. Participants in breast screening programmes therefore cannot be considered a homogeneous entity. Caution should be exercised when assessing the impact of screening procedures on entire populations as this approach might mask an important diversity of response.  相似文献   
89.
Lu  D; Kalafatis  M; Mann  KG; Long  GL 《Blood》1994,84(3):687-690
Clinical manifestations of arterial and venous thrombosis in a family with protein C deficiency was associated with two mutations in the light chain of protein C: Glu20-->Ala and Val34-->Met. Further studies showed that the mutation Glu20-->Ala which eliminated a gamma- carboxylation site was exclusively responsible for the anticoagulant defect of activated protein C (APC). Membrane-bound human factor Va is inactivated by APC after two sequential cleavages of the heavy chain at Arg506 and Arg306. Human factor Va inactivation by human recombinant APC (rAPC) and a mutant molecule with an alanine instead of a glutamic acid at position 20 (rAPC(gamma 20A)) was investigated in the presence and absence of phospholipid vesicles. During a 2-hour incubation period of the cofactor with either rAPC or rAPC(gamma 20A). In the absence of a membrane surface, factor Va is cleaved quantitatively at Arg506 and retains approximately 60% of its initial cofactor activity. After a 2- hour incubation period with rAPC membrane-bound factor Va has no cofactor activity, whereas in the presence of a membrane surface and rAPC(gamma 20A) factor Va retains 60% of its initial cofactor activity. The completed loss in factor Va cofactor activity upon incubation of the membrane-bound cofactor with phospholipid vesicles and rAPC is associated with cleavages at Arg506 and Arg306, whereas membrane-bound factor Va cleavage at Arg306 by rAPC(gamma 20A) is impaired, resulting in a cofactor that is cleaved at Arg506. Slow cleavage at Arg306 occurs when membrane-bound factor Va is incubated with rAPC(gamma 20A) and only small amounts of fragments of M(r) = 45,000 and 30,000 are noticed. Our data show that the genetic defect which leads to the absence of a gamma-carboxylation site at Glu20 impairs membrane binding of human APC, which in turn is required for cleavage of factor Va at Arg306 and inactivation of the cofactor. The consequence of impaired membrane-dependent cleavage at Arg306 is manifested in vivo by venous and arterial thrombosis.  相似文献   
90.
Parathyroid hormone‐related protein (PTHrP) is an integral mediator of physiologic and pathologic processes and has demonstrated actions in the periodontium. PTHrP functions via AP‐1, and specifically through JunB. This study identified JunB‐dependent downstream mediators of PTHrP using OCCM cementoblastic transfectants with JunB over‐ or reduced expression. Over‐expressing cells showed an increase in proliferation, while the opposite was seen in siRNA transfected cells. Microarray analysis of over‐expressing cells revealed more than 1000 regulated genes. Three genes were investigated in more detail. The PTH/PTHrP receptor (PTHR1) and ephrin B1 (EfnB1) were down‐regulated, and vascular cell adhesion molecule‐1 (VCAM‐1) was up‐regulated with JunB over‐expression. JunB siRNA transfectants had increased PTHR1, but reduced ephrin B1 and unaltered VCAM‐1 in vitro. To validate these targets, parental OCCM cells and primary osteoblasts were treated with PTHrP, resulting in reduced PTHR1 and ephrin B1, and increased VCAM‐1. Cell transfectants were implanted subcutaneously in vivo, and microarray analysis and RT‐PCR performed. Over‐expression of JunB down‐regulated PTHR1 and ephrin B1, and increased VCAM‐1. JunB siRNA transfectant implants had increased PTHR1 and ephrin B1, but no altered VCAM‐1. These data highlight new gene targets for PTHrP and indicate JunB is a critical mediator of PTHrP actions.  相似文献   
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