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61.
Summary Using acetylcholinesterase histochemical and choline acetyltransferase immunocytochemical localization methods, this study has provided conclusive evidence for the existence of cholinergic neurons in the external cuneate nucleus of gerbils. By light microscopy, both acetylcholinesterase and choline acetyltransferase labelling was confined to the rostral portion of the external cuneate nucleus. Ultrastructurally, acetylcholinesterase reaction products were found in the nuclear envelope, cisternae of rough endoplasmic reticulum and Golgi saccules of some somata and large dendrites as well as in the membranes of small dendrites, myelinated axons and axon terminals. These neuronal elements were also stained for choline acetyltransferase; immunoreactivity was associated with nuclear pores, nuclear envelope, perikaryal membrane and all the membranous structures within the cytoplasm. Of the total choline acetyltransferase-labelled neuronal profiles analysed, 79% were myelinated axons, 15% dendrites, 4% somata and 2% axon terminals. The immunostained axon terminals consisted of two types containing either round (Rd type; 62.5%) or pleomorphic (Pd type; 37.5%) vesicles. Both were associated directly with choline acetyltransferase-positive dendrites. In contrast to the paucity of choline acetyltransferase-labelled axon terminals, numerous choline acetyltransferase-positive myelinated axons were present. It may thus be hypothesized that most, if not all, of the external cuneate nucleus cholinergic neurons are projection cells; such cells may give rise to axonal collaterals which synapse onto their own dendrites for possible feedback control. Choline acetyltransferase-positive dendrites were contacted by numerous unlabelled presynaptic boutons, 60% of which contained round or spherical synaptic vesicles (Rd boutons) and 40% flattened vesicles (Fd boutons), suggesting that these neurons are under strong inhibitory control. The preferential concentration of cholinergic components in the rostral external cuneate nucleus may be significant in the light of the highly organized somatotopy in the external cuneate nucleus and its extensive efferent projections to medullary autonomic-related nuclei. Our results suggest that the cholinergic neurons may be involved in somatoautonomic integration. 相似文献
62.
G. Pilkington S. Juneja L. Tan J. Matthews J. Quirk G. Lee P. Ironside I. Cooper D. Jose 《Hematological oncology》1993,11(4):195-205
The prognostic value of immunophenotyping lymphomas with a panel of monoclonal antibodies (Mab) to various lymphoid antigens was assessed by studying 47 cases of diffuse large cell lymphoma. Cell suspensions were analysed by flow cytometry after labelling by indirect immunofluorescence. Thirty-eight cases were demonstrated to be of B cell and nine of T cell phenotype. Univariate analysis demonstrated that survival was significantly longer in patients expressing higher levels of HLA-DR (p=0·01) and normal levels of CD8 (p=0·04) but was not significantly associated with any of the other antigens. Our results support the possible value of HLA-DR in determining the prognosis of patients with diffuse large cell lymphoma. 相似文献
63.
64.
Michael Groeneweg Suzan Tan Annemieke M. Boot Johan C. de Jongste Jan Bouquet Maarten Sinaasappel 《Journal of cystic fibrosis》2002,1(4):583-280
BACKGROUND: Assessment of nutritional status in children with cystic fibrosis (CF) is clinically relevant. Methods to measure nutritional status should be reliable and non-invasive, and reference values should be available. AIM: To compare weight and height measurements and measurements of specific body compartments in children with CF. METHODS: In a cross-sectional survey of 58 children with CF (28 females), we compared height and weight (expressed as: weight-for-height, body mass index (BMI), height-for-age and weight-for-age) with fat mass (skinfold sum (SFS)), muscle mass (upper arm circumference (UAC)) and bioelectrical impedance analysis (BIA). Results were expressed as Z-scores, using Dutch reference values. RESULTS: BMI and weight-for-height were within the normal range (mean Z-score (range): -0.13 (-1.5, 2.7) and -0.02 (-1.7, 2.8)). Weight and height corrected for age were below normal (mean Z-score (range): -0.79 (-2.4, -0.05) and -1.2 (-2.8, 1.4) (P<0.01)). Lean body mass by skinfold sum (LBM(sfs)), UAC and BIA were also significantly below reference values (mean Z-score (range): -0.9 (-2.2, 1.8), -0.95 (-2.4, 1.8) and -1.1 (-3.6, 1.0) (P<0.01)). Lean body mass (LBM) by BIA correlated with LBM(sfs). BIA systematically underestimated LBM in both CF patients and in control subjects. CONCLUSION: Nutritional status of children with CF must be evaluated, using age-corrected weight and height expressed in Z-score. LBM estimated by SFS, UAC and by BIA appear to be useful, although longitudinal studies in CF children should be performed to evaluate their clinical significance in detecting changes in nutritional status. 相似文献
65.
Nonablative dermal remodeling with a 585-nm, 350-microsec, flashlamp pulsed dye laser: clinical and ultrastructural analysis. 总被引:1,自引:0,他引:1
David Goldberg M Tan M Dale Sarradet Marsha Gordon 《Dermatologic surgery》2003,29(2):161-3; discussion 163-4
BACKGROUND: A nonablative 350-microsec, 585-nm, flashlamp pulsed dye laser is currently being used for the treatment of rhytides. OBJECTIVE: To analyze both clinical rhytid improvement and electron microscopic evidence of ultrastructural changes after treatment with a nonablative 350-microsec, 585-nm, flashlamp pulsed dye laser. RESULTS: At 6 months after two treatments, 40% of the treated subjects noted mild improvement in rhytid appearance. Nontreating physician evaluation revealed some degree of improvement in 50% of the treated subjects. Mild improvement in quality and texture of the skin was also reported by 50% of the subjects. Electron microscopic evaluation showed ultrastructural changes that are consistent with new collagen formation. CONCLUSION: Treatment with a nonablative 350-microsec, 585-nm, flashlamp pulsed dye laser can lead to both clinical and electron microscopic evidence of improvement in photo-damaged skin. 相似文献
66.
A double-blinded study was conducted to compare the effects of mupirocin and tetracycline ointments in the treatment of skin infections. 111 patients were available for clinical assessment, of which 53 were treated with mupirocin and 58 treated with tetracycline. Clinically, both groups were improved, and there was no significant difference. Bacteriological assessment however revealed a better response to mupirocin. Staphylococcus aureus and Streptococcus pyogenes were the most common organisms isolated. 99% of Staphylococci were sensitive to mupirocin compared with 61% to tetracycline and 29% to penicillin G. 57% of Group A beta haemolytic Streptococci were resistant to tetracycline compared to 14% to mupirocin. Gram-negative organisms were mostly resistant to both preparations. No side effects were observed in both treatment groups. This study suggests that mupirocin is a safe and effective topical preparation for treating most of our common skin infections. 相似文献
67.
Audit of 149 consecutive carotid endarterectomies performed by a single surgeon in a district general hospital over a 12-year period. 总被引:1,自引:1,他引:0 下载免费PDF全文
L. C. Tan G. L. Sutton N. J. Taffinder M. Perry T. Fail 《Annals of the Royal College of Surgeons of England》1996,78(4):340-344
Carotid endarterectomy has been established by two large randomised controlled trials (European Carotid Surgery Trial (ECST) and North American Symptomatic Carotid Endarterectomy Trial (NASCET)) as an important surgical procedure for the prevention of ischaemic strokes in patients presenting with transient cerebral ischaemia or non-disabling strokes attributable to severe ipsilateral carotid artery stenosis. The operation carries significant risk of death and stroke and it has been advocated by some that carotid endarterectomy should only be performed in a small number of designated regional centres in order to achieve good surgical results. It is doubtful that the regional centres alone can cope with the increasing numbers of patients requiring carotid endarterectomy and there is therefore a requirement for the procedure to be carried out by vascular surgeons in district general hospitals. It is important that surgical results are audited to ensure that comparable outcomes are achieved. We present an audit of our experience of carotid endarterectomy since 1981. A total of 149 consecutive carotid endarterectomies were performed by a single surgeon with a special interest in carotid surgery. The results are comparable to ECST with a 30-day mortality of 0% and an overall 30-day stroke rate of 5.7% (major strokes) for patients with severe, ie 70-99%, ipsilateral carotid artery stenoses. We have shown that carotid endarterectomy is an operation that can be performed safely and with good results by suitably trained surgeons in district general hospitals. 相似文献
68.
对1997年以来423例病态喉的频闪喉镜表现进行分析,结果显示声带有病理改变者其粘膜波、振幅、闭合相、运动周期性、对称性均有不同程度的变化,这种变化能直接反映声带病变的深度及范围,对喉部疾病的诊断、鉴别诊断、治疗指导及预后评价具有重要意义. 相似文献
69.
70.
Alan G. Meehan Iain C. Medgett David F. Story 《Naunyn-Schmiedeberg's archives of pharmacology》1988,337(5):500-503
Summary The present study examined the involvement of Ca+ mobilization in the amplifying effect of serotonin on steady-state responses of rabbit isolated perfused ear artery to exogenous noradrenaline (NA; 0.001–3 ol/l). In contrast to its marked amplifying effect on responses to NA, serotonin in the subconstrictor concentration of 100 nmol/l had no effect on responses to KCl. The Ca+-entry blocking drug diltiazem (10 gmol/1) decreased responses to NA; in addition, the amplifying effect of serotonin on responses to NA was reduced by diltiazem. Lowering the concentration of Ca+ in the Krebs-Henseleit perfusion solution from 2.5 to 0.25 mmol/l also reduced both responses to NA and the amplifying effect of serotonin. Using the method of Manzini et al. (1982), separate intra- and extracellular Ca+-dependent responses to NA were obtained. Serotonin had no effect on intracellular Ca+-dependent responses to NA but enhanced extracellular Ca2+-dependent NA responses. These results suggest that the amplifying effect of serotonin on responses of rabbit ear artery to exogenous NA involves a selective enhancement of the component of the NA response which is dependent on extracellular Ca+; serotonin may increase NA-evoked entry of Ca2+ into the vascular smooth muscle cells through receptor-operated Ca+ channels.
Send offprint requests to A. G. Meehan at the above address 相似文献