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1.
Objective: Considering the growing use of cellular phones and the fast appearance of new phone models, the electromagnetic interference of currently popular cellular phones on electronic medical equipment was tested. Methods: Three Personal Communication System cellular phones were put at different distances from multiple electronic medical devices, the interference effect was observed and the electromagnetic field strength measured with a spectrum analyser. Results: Only two small pieces of equipment, the CO2 airway adapter and the haemoglucostix meter were affected and then only when the phone was in very close proximity. Conclusion: Compared to the results of our study in 1997 testing Global System for Mobile Communication phones, the Personal Communication System phones generated less electromagnetic interference. However a much larger scaled study and an accurate international electromagnetic interference standard are recommended before any change in the current restrictive hospital policy on mobile phone usage could be recommended. 相似文献
2.
Paired kidney analysis of tacrolimus and cyclosporine microemulsion-based therapy in Chinese cadaveric renal transplant recipients 总被引:5,自引:0,他引:5
Chi Yuen Cheung Kim Ming Wong Hoi Wong Chan Yan Lun Liu Yiu Han Chan Ho Sing Wong Wai Leung Chak Koon Shing Choi Ka Foon Chau Chun Sang Li 《Transplant international》2006,19(8):657-666
Few studies used paired kidneys for comparison between tacrolimus and cyclosporine in renal transplantation. Most of the published data used whole blood trough levels for drug monitoring. However, the use of limited sampling strategy and abbreviated formula to estimate the 12-h area under concentration-time curve (AUC(0-12)) allowed better prediction of drug exposure. Sixty-six first cadaveric renal transplant recipients receiving paired kidneys were randomized to receive either tacrolimus-based (n = 33) or cyclosporine microemulsion (Neoral)-based therapies (n = 33). Abbreviated AUC(0-12) was used for drug monitoring and dose titration. Mean follow-up duration was 2.8 +/- 2 years. The patient and graft survival were comparable. Fewer incidence of acute rejection was observed in tacrolimus group (15% vs. 27.3%) though the difference was not significant (P = 0.23). The absolute value and the rate of decline of creatinine clearance were both significantly better in tacrolimus-treated patients. Prevalence of hypertension, post-transplant diabetes mellitus, infection, and malignancy were similar in both groups. Prevalence of hypercholesterolemia (11/33 vs. 4/33) and gum hypertrophy (6/33 vs. 1/33) was more common in cyclosporine-treated patients (P = 0.04 in both parameters). This was the first prospective, randomized study with paired kidney analysis showing the renal function was significantly better in tacrolimus-treated patients than in cyclosporine-treated patients. 相似文献
3.
Critchley Hilary O.D.; Bailey Deborah A.; Au Chak L.; Affandi Biran; Rogers Peter A.W. 《Human reproduction (Oxford, England)》1993,8(10):1632-1639
The bleeding problems experienced by users of subdermal levonorgestrelimplants (Norplant) remain unexplained. The aim of the presentstudy was to investigate the oestrogen (ER) and progesteronereceptor (PR) distribution in levonorgestrel-treated endometrialbiopsies from 31 subjects recruited in Jakarta, Indonesia, andto compare the sex steroid receptor immunostaining with thatof endometrium from 58 normally cycling women from Melbourne,Australia. Sex steroid receptor immunoreactivity was additionallycompared with days of exposure to subdermal levonorgestrel,serum oestradiol and progesterone levels and days of bleedingduring a 90-day reference period. An immunohistochemical techniquewith an alkaline phosphatase anti-alkaline phosphatase (APAAP)detection system for use in formalin-fixed paraffin wax embeddedendometrial tissue was employed. Significantly greater meanimmunostaining scores of stromal PR were observed in Norplantcompared with control endometrium at all stages across the cycle.No significant correlations were demonstrated between sex steroidreceptor immunostaining and days of exposure to subdermal levonorgestrel,serum oestradiol or progesterone concentrations or days of bleedingduring a 90-day reference period. Whether the elevated stromalPR immunostaining in Norplant-treated endometrium is a consequenceof increased synthesis or reduced turnover of receptor remainsunclear. As yet it is undetermined whether increased PR immunoreactivitycorresponds to an increase in number of functional PR. 相似文献
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Ghrelin expression in hyperplastic and neoplastic proliferations of the enterochromaffin-like (ECL) cells 总被引:1,自引:0,他引:1
Ghrelin, a recently discovered peptide isolated from the gastric corpus mucosa, is believed to be important in the regulation
of growth hormone secretion and has been shown to increase appetite and food intake as well. It may also have other gastrointestinal
and cardiac functions. Because a cell of origin for ghrelin has not been convincingly identified in the gastric mucosa thus
far, we studied the immunohistochemical expression of ghrelin in proliferative lesions of the enterochromaffin-like (ECL)
cells—a cell that is not only exclusively confined to the gastric corpus mucosa but is its dominant endocrine cell type as
well.
Formalin-fixed, paraffin embedded tissues from three cases of gastric ECL cell hyperplasia and five ECL carcinoids (three
with coexisting foci of diffuse, linear, and micronodular hyperplasia) were immunohistochemically stained for ghrelin, using
a commercially available antibody. The Sevier-Munger stain for ECL cells and immunohistochemical stains for chromogranin,
gastrin, serotonin, somatostatin, and vesicular monoamine transporter-2 (VMAT-2) were performed on parallel sections for correlation
with the ghrelin staining results.
All ECL cell carcinoids and hyperplastic lesions were positive for both the Sevier-Munger and the immunohistochemical stains
for chromogranin and VMAT-2. Immunoreactivity for ghrelin was seen in 4/5 ECL carcinoids, all cases of ECL cell hyperplasia,
as well as in all areas with linear and micronodular hyperplasia adjacent to the ECL cell carcinoids. In each instance, such
staining was confined to the Sevier-Munger, and VMAT-2 positive cells only.
Our findings indicate that the ECL cells are either the ghrelin-producing cells of the gastric mucosa or acquire the capability
to synthesize ghrelin during proliferative states encompassing the entire hyperplasia to neoplasia spectrum. In view of the
orexigenic and other known actions of ghrelin, the functional and/or biologic significance of ghrelin production in such ECL
cell proliferations needs to be investigated further. 相似文献
6.
Epithelial-myoepithelial tumor is extremely rare as a pulmonary neoplasm. Only 20 cases have been reported to date, of which 14 were malignant. We report a case of intrabronchial epithelial-myoepithelial carcinoma in a 73-year-old man with a history of heavy smoking. The tumor was well-circumscribed and caused distal airway obstruction. Histologically, the tumor showed glandular and solid architecture. The glands were composed of an inner layer of epithelial cells and an outer layer of myoepithelial cells. The solid areas consisted of spindle-shaped myoepithelial cells. Immunohistochemical staining was positive for p53 and c-Kit (CD117). Focal atypia and increased mitotic activity were present, but no vascular invasion or nodal metastasis was identified. 相似文献
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