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D Sykes R Dewar K Mohanaruban K Donovan F Nicklason D M Thomas D Fisher 《BMJ (Clinical research ed.)》1990,300(6718):162
OBJECTIVE--To compare the interobserver and intraobserver variability of blood pressure measurements in geriatric patients in atrial fibrillation and in sinus rhythm. DESIGN--Prospective assessment of blood pressure measurements carried out in random order in two groups of elderly patients by five doctors unaware of the aims of the study. SETTING--Acute assessment wards for geriatric medicine, Cardiff Royal Infirmary. PATIENTS--50 Elderly patients in sinus rhythm and 50 in atrial fibrillation. MAIN OUTCOME MEASURES--Interobserver and intraobserver variability of blood pressure measurements in the two groups expressed as the coefficient of variability and compared by the Mann-Whitney U test. RESULTS--Interobserver variability was significantly greater in the patients with atrial fibrillation for both systolic and diastolic pressures. Intraobserver variability was significantly greater in the atrial fibrillation group for diastolic pressures but the difference was not significant for systolic pressures. These differences were not related to pulse rate, age, or level of blood pressure. CONCLUSIONS--The findings suggest that in the presence of atrial fibrillation physicians'' interpretations of Korotkoff sounds are less uniform, which may have important clinical implications. Possibly a standardised methodology may overcome this problem. 相似文献
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The increasing demand for sterilization as a permanent and effective form of birth control leads one to consider the various methods available to achieve this end. Tubal cauterization and excision by laparoscopy appears to be a safe, efficient method.The technique used is carefully reviewed step by step. The absence of major complications in this series of 115 consecutive laparoscopies certainly supports the safety of the procedure. The low morbidity, short hospital stay and minimal time required appeal particularly to the working mother. The absence of an abdominal scar is also much appreciated. The procedure, when used for investigation of infertility, provides far more information than other current methods. 相似文献
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Septisol antiseptic foam (0.23% hexachlorophene in a 46% ethyl alcohol base) is a new surgical scrub agent for both primary and re-entry use that is designed to minimize the harsh effects to the skin of the conventional scrub while retaining effective antibacterial properties. A preliminary surgical scrub study of 1-week duration yielded an immediate reduction in resident flora of 92% from an average single scrub coupled with a residual bacteriostatic effect from repeated use that gave a plateau at 57% of the pretest resident population level. A separate study demonstrated complete elimination of both gram-positive and gram-negative transients from the skin with a single application of the product. In an 8-week surgical scrub study, equal effectiveness was shown between Septisol antiseptic foam and a standard 3% hexachlorophene detergent. However, Septisol antiseptic foam offers considerable advantage in minimizing the harsh effects to the skin of the conventional surgical scrub and results in a substantially lower hemic level of hexachlorophene in the user than that obtained with 3% hexachlorophene detergent. Sampling was conducted by the fingerprint impression plate technique of Gale. 相似文献
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Summary
Anacystis nidulans will take up and accumulate chloride ions. When the external concentration was 0.2 mM Cl- the level in the cells was 2.8 mM Cl- and under these conditions the flux across the cell surface was in the region of 10-13equiv Cl-·sec-1·cm-2. It is suggested that this Cl- influx is active and operates against an electrochemical potential gradient estimated to be 117 mV or 2.68 kcal/mole. The uptake of 36Cl was inhibited by low temperatures and there was a net loss of Cl- from the cells with the level decreasing towards the equilibrium value as estimated from K+ distribution. Although the active influx of Cl- was often stimulated by light this was not always the case. Dark storage treatment and regulation of the chlorophyll a/phycocyanin ratios as well as total pigment content of the cells did not clarify the conditions which brought about light stimulation. Moreover, the metabolic inhibitors CCCP and CMU and also the use of anaerobic conditions did not clearly indicate the relationship between the influx mechanism and light-dark metabolism and no firm conclusions could be made about the nature of the energy source. The variation in the degree of light stimulation probably reflects the fact that in this procaryotic organism the photosynthetic and respiratory units are located on the same membrane systems and are in very close proximity to the probable site of the Cl- pump, the plasmalemma.Abbreviations CCCP
carbonyl cyanide m-chlorophenylhydrazone
- CMU
3-(4-chlorophenyl)-1,1-dimethylurea 相似文献
49.
Simon Dewar Natasha Sienkiewicz Han B. Ong Richard J. Wall David Horn Alan H. Fairlamb 《The Journal of biological chemistry》2016,291(47):24768-24778
The aim of this study was to identify and characterize mechanisms of resistance to antifolate drugs in African trypanosomes. Genome-wide RNAi library screens were undertaken in bloodstream form Trypanosoma brucei exposed to the antifolates methotrexate and raltitrexed. In conjunction with drug susceptibility and folate transport studies, RNAi knockdown was used to validate the functions of the putative folate transporters. The transport kinetics of folate and methotrexate were further characterized in whole cells. RNA interference target sequencing experiments identified a tandem array of genes encoding a folate transporter family, TbFT1–3, as major contributors to antifolate drug uptake. RNAi knockdown of TbFT1–3 substantially reduced folate transport into trypanosomes and reduced the parasite''s susceptibly to the classical antifolates methotrexate and raltitrexed. In contrast, knockdown of TbFT1–3 increased susceptibly to the non-classical antifolates pyrimethamine and nolatrexed. Both folate and methotrexate transport were inhibited by classical antifolates but not by non-classical antifolates or biopterin. Thus, TbFT1–3 mediates the uptake of folate and classical antifolates in trypanosomes, and TbFT1–3 loss-of-function is a mechanism of antifolate drug resistance. 相似文献
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