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991.
Cough is commonly used as an outcome measure in clinical studies, although the subjective reporting of cough is unreliable when compared to objective measures. We describe an inexpensive new ambulatory cough meter that is based on a disused Holter monitor. The cough meter consists of a Holter monitor and a cough processor, designed on a computer to select the most appropriate filters. The cough meter was then validated against the overnight tape recorder on 21 occasions in 18 children (aged 6-15 yrs). The agreement between the cough meter and the tape recorder was good (mean difference of -0.3 coughs x h(-1); limits of agreement -2.2 to 1.7 coughs x h(-1)). We conclude that our newly described ambulatory cough meter provides a valid and inexpensive method of objectively monitoring cough for up to 24 h. 相似文献
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1. Interactions between autacoids may play important roles in the regulation of blood flow in the foetal placenta. In order to investigate this aspect of placental haemodynamics, human normal-term placentae were perfused in vitro and the responses of the foetal vessels to various combinations of vasoactive agents were determined. 2. Vasoconstriction responses to 5-hydroxytryptamine (5-HT) were potentiated in the presence of endothelin-1 (ET-1), the thromboxane A2-mimetic U46619 and a nitric oxide synthase inhibitor, N-nitro-L-arginine (NOLA), but not in the presence of angiotensin II. 3. N-Nitro-L-arginine caused vasoconstriction of the perfused placenta and indomethacin attenuated this effect and blocked the potentiation of the 5-HT response by NOLA. 4. Indomethacin did not affect ET-1-induced pressure increases and infusion of U46619 had no effect on release of ET-like immunoreactivity into the foetal placental circulation. 5. The present study provides evidence of interactions between several autacoids in human perfused placentae in vitro. These interactions may play important roles in foetal placental haemodynamics in normal or pathological situations. 相似文献
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HR Chakkalath CM Theodos JS Markowitz MJ Grusby LH Glimcher RG Titus 《Canadian Metallurgical Quarterly》1995,171(5):1302-1308
Class II major histocompatibility complex (MHC)-deficient (H-2b) mice do not express I-A or I-E molecules and, as a result, do not develop CD4 cells. Thus, they represent the ideal model for examining the importance of CD4 cells and MHC class II molecules in resistance to infection with Leishmania major and the capacity of MHC class I-restricted T cells to mediate resistance to L. major. Class II MHC-deficient mice and control (C57BL/6, normal and nude) mice were infected with L. major. Although MHC class II-deficient mice were able to control infection more effectively than nude mice, cutaneous lesions on the mice eventually progressed, and parasite replication became uncontrolled. These results suggest that CD4 cells and MHC class II molecules are essential for resistance to L. major and that in the absence of these cells and molecules, such mice can transiently control infection with L. major but are unable to resolve such infections. 相似文献
998.
SN Cousens M Zeidler TF Esmonde R De Silva JW Wilesmith PG Smith RG Will 《Canadian Metallurgical Quarterly》1997,315(7105):389-395
OBJECTIVE: To identify changes in the occurrence of Creutzfeldt-Jakob disease that might be related to the epidemic of bovine spongiform encephalopathy. DESIGN: Epidemiological surveillance of the United Kingdom population for Creutzfeldt-Jakob disease based on (a) referral of suspected cases by neurologists, neuropathologists, and neurophysiologists and (b) death certificates. SETTING: England and Wales during 1970-84, and whole of the United Kingdom during 1985-96. SUBJECTS: All 662 patients identified as sporadic cases of Creutzfeldt-Jakob disease. MAIN OUTCOME MEASURES: Age distribution of patients, age specific time trends of disease, occupational exposure to cattle, potential exposure to causative agent of bovine spongiform encephalopathy. RESULTS: During 1970-96 there was an increase in the number of sporadic cases of Creutzfeldt-Jakob disease recorded yearly in England and Wales. The greatest increase was among people aged over 70. There was a statistically significant excess of cases among dairy farm workers and their spouses and among people at increased risk of contact with live cattle infected with bovine spongiform encephalopathy. During 1994-6 there were six deaths from sporadic Creutzfeldt-Jakob disease in the United Kingdom in patients aged under 30. CONCLUSIONS: The increase in the incidence of sporadic Creutzfeldt-Jakob disease and the high incidence in dairy farmers in the United Kingdom may be unrelated to bovine spongiform encephalopathy. The most striking change in the pattern of Creutzfeldt-Jakob disease in the United Kingdom after the epidemic of bovine spongiform encephalopathy is provided by the incidence in a group of exceptionally young patients with a consistent and unusual neuropathological profile. The outcome of mouse transmission studies and the future incidence of the disease in the United Kingdom and elsewhere, will be important in judging whether the agent causing bovine spongiform encephalopathy has infected humans. 相似文献
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NA Rieger RG Sarre GT Saccone A Hunter J Toouli 《Canadian Metallurgical Quarterly》1997,67(8):566-570
BACKGROUND: To determine the long-term outcome of postanal repair, and to assess whether the preoperative and physiological tests had any bearing on this outcome. Review included an opportunity for assessment with anal manometry and anal ultrasound. METHOD: Review of all patients (n = 22) over a 10 year period from 1986 to 1996. Comparison was of pre-operative symptoms to symptoms at review. Correlation of outcome with pre-operative manometry and the results of manometry and ultrasound at review (n = 6) was determined. RESULTS: Assessment was possible in 19 of the 22 patients. Follow-up ranged from 2 to 10 years (median, 8 years). Two had stomas created at 6 and 9 months and are considered failures. Seven patients considered the operation a success, in four it improved their symptoms and in six it was considered a failure. Comparison of pre- and postoperative symptoms scores found a statistically significant improvement (P = 0.0093; two-tailed Wilcoxon signed rank sum test). The outcome was not influenced by the results of pre-operative anal manometry. Anal ultrasound found five sphincter defects in six patients. Such defects did not preclude improvement from postanal repair. CONCLUSIONS: Although the results showed improvement or success in only 11 (58%) of the patients this was felt to be important given that these patients may have few alternatives other than complicated procedures or a stoma. Postanal repair has a place in the management of faecal incontinence. 相似文献
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