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61.
To determine the utility of the lateral view of the chest in emergency department patients, records of all patients who had had 2-view chest x-rays ordered in the emergency department were reviewed retrospectively. A study radiologist recorded a reading of the posteroanterior (PA) radiograph alone. The lateral radiograph was then provided, along with the PA view, and a second reading was recorded. A comparison was then made between the first and second readings.A total of 417 sets of x-rays were included. The PA view alone successfully diagnosed or suspected 92% of pulmonary nodules, 95% of effusions, 97% of cases of emphysema, 98% of pneumonias, and 100% of cases of cardiomegaly, pulmonary edema, interstitial pulmonary disease, and atelectasis.In the emergency department patient population, lateral views of the chest have minimal diagnostic yield and therefore may be used selectively to safely decrease the amount of breast radiation exposure to young women.  相似文献   
62.
The present conventional methods for determination of Hemoglobin (Hb) concentration in whole blood depend on the direct colorimetric measurement of chemically modified Hb following its release from red cells by lysis. This paper examines an alternative, indirect method which does not require initial red cell lysis, corrects for the falsely elevated Hb due to the lipemic plasma and determines whether elevated WBC count effects a change in the Hb value, without the tedious laboratory manipulations currently required to correct for these artifacts. The method is simple, uncomplicated and is based on the observation of a constant ratio (2.98) between the Mean Corpuscular Volume (MCV) and the Mean Corpuscular Hemoglobin (MCH) indices obtained from standard electronic counters in use in most laboratories. The Hb concentration is calculated by the equation: [formula: see text]. The resultant Hb measurements show an acceptable degree of accuracy and precision when compared with the direct measurements obtained from a Coulter Model S + I, even in the presence of a high WBC or lipid.  相似文献   
63.
Problems arising from controlled ovarian hyperstimulation for intrauterine insemination, such as premature luteinization and asynchronous ovarian follicular development, are identical to those encountered with controlled ovarian hyperstimulation for in vitro fertilization (IVF) and gamete intrafallopian transfer (GIFT). It has been suggested that the adjunctive use of GnRH agonists for controlled ovarian hyperstimulation improves the efficiency of GIFT and IVF cycles. We hypothesized that adjunctive use of leuprolide acetate, a GnRH agonist, would have a similarly beneficial effect on cycle quality and cycle fecundity in subfertile women treated with controlled ovarian hyperstimulation and intrauterine insemination. We randomly assigned the first cycle of controlled ovarian hyperstimulation and intrauterine insemination for each of 97 subfertile women to include either human menopausal gonadotropins (hMGs) alone or hMGs following midluteal pre-treatment with leuprolide. If a pregnancy did not occur in the first cycle, the woman was given the other treatment in the second cycle. Although the cycles that included leuprolide required a larger amount of hMGs and more days of stimulation per cycle, the mean estradiol concentrations and numbers of follicles were not different. Despite prevention of premature luteinization with leuprolide, the cycle fecundity was not different between groups (0.11 with adjunctive leuprolide treatment and 0.22 with hMGs alone). We conclude that in unselected subfertile patients, the adjunctive use of leuprolide for controlled ovarian hyperstimulation and intrauterine insemination does not improve cycle fecundity compared with treatment cycles that do not include adjunctive leuprolide therapy.  相似文献   
64.
1. The aim of this study was to determine whether the site of action of relaxin as a relaxant of rat myometrium is at the cell membrane or at an intracellular-site. Therefore, the potency of relaxin was determined against spasms reliant predominantly upon either extracellular Ca2+ or intracellular Ca2+. Uterine spasms dependent upon extracellular Ca2+ were elicited by (i) oxytocin (0.2 nM) (ii) Bay K 8644 (1 microM) in 10 mM K(+)-rich PSS and (iii) KCl (80 mM). Uterine spasm dependent upon intracellular Ca2+ was elicited by oxytocin (20 nM) in the presence of nifedipine (500 nM). The effects of relaxin against these spasmogens were compared with those of levcromakalim, nifedipine and salbutamol. 2. Relaxin (0.2-6.3 nM), levcromakalim (25-800 nM), salbutamol (1-63 nM) and nifedipine (1-250 nM) caused concentration-dependent inhibition of the spasm evoked by oxytocin (0.2 nM) and relaxin was the most potent relaxant. 3. Relaxin and nifedipine were slightly less potent against the spasm induced by Bay K 8644 (1 microM) than against spasm induced by oxytocin (0.2 nM) (15 fold and 13 fold respectively). Levcromakalim and salbutamol were equipotent against the spasm evoked by Bay K 8644 (1 microM) and that evoked by oxytocin (0.2 nM). 4. Relaxin induced only 47 +/- 7% inhibition of the KCl (80 mM)-evoked spasm at a concentration of 0.8 microM. Levcromakalim was much less potent (427 fold) against the spasm evoked by KCl (80 mM) than against the spasm evoked by oxytocin (0.2 nM). The potency of salbutamol against the spasm evoked by KCl (80 mM) was modestly reduced (14 fold) compared to that against the spasm evoked by oxytocin (0.2 nM). The potency of nifedipine against the KCl (80 mM)-evoked spasm was not different from that against the oxytocin (0.2 nM)-evoked spasm. 5. The potencies of relaxin and levcromakalim against the spasm evoked by oxytocin (20 nM) + nifedipine (500 nM) were greatly reduced (74 fold and 234 fold respectively) compared to their potencies against the spasm evoked by oxytocin (0.2 nM). The potency of salbutamol against these two spasmogens was not different. 6. Relaxin was much less potent against the spasm dependent upon intracellular Ca2+ (that induced by oxytocin (20 nM) + nifedipine (500 nM)) than against the spasms dependent upon extracellular Ca2+, those induced by oxytocin (0.2 nM) and Bay K 8644 (1 microM). In this regard, relaxin resembled levcromakalim and nifedipine rather than salbutamol. Therefore, the major site of action of relaxin appears to be located at the plasma membrane rather than at an intracellular level. The observation that relaxin was less effective against the KCl (80 mM)-induced spasm than against the oxytocin (0.2 nM)-evoked spasm may indicate that relaxin has a minor action involving K(+)-channel opening. 7. High concentrations of relaxin (up to 1 microM) induced significant inhibition of the spasm dependent upon intracellular Ca2+. Thus at high concentrations relaxin also appears to have an additional intracellular action.  相似文献   
65.
One hundred and five patients with discrete breast lumps were examined with a 10 MHz Doppler ultrasonic flowmeter. Doppler flow signals were analysed on an Angioscan spectrum analyser. Recordings from the opposite normal breast were taken as controls and signals from the two sides compared. In 23 patients signals from the normal breast could not be recorded and therefore results of the remaining 82 patients are reported. These included 39 patients with carcinoma, 20 with fibroadenoma, 12 with cyclical nodularity and 11 with cysts. Malignant lumps exhibited significantly higher peak systolic (S) and minimum diastolic frequencies (D) in comparison to the control breast. Fibroadenoma also had a higher S and D than those of the opposite normal breast. Signals over cysts and cyclical nodularity showed no significant difference from the recordings over the control side. Despite significantly higher systolic and diastolic frequencies in the cancer group in comparison to benign lumps and normal breast, considerable overlap in the values was seen between cancer and other groups. Therefore the patterns on 10 MHz Doppler sonography are not sufficiently specific to discriminate benign from malignant breast lumps.  相似文献   
66.
In 1984, a prospective cohort study, Coronary Artery Risk Development in Young Adults (CARDIA) was initiated to investigate life-style and other factors that influence, favorably and unfavorably, the evolution of coronary heart disease risk factors during young adulthood. After a year of planning and protocol development, 5,116 black and white women and men, age 18-30 years, were recruited and examined in four urban areas: Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota, and Oakland, California. The initial examination included carefully standardized measurements of major risk factors as well as assessments of psychosocial, dietary, and exercise-related characteristics that might influence them, or that might be independent risk factors. This report presents the recruitment and examination methods as well as the mean levels of blood pressure, total plasma cholesterol, height, weight and body mass index, and the prevalence of cigarette smoking by age, sex, race and educational level. Compared to recent national samples, smoking is less prevalent in CARDIA participants, and weight tends to be greater. Cholesterol levels are representative and somewhat lower blood pressures in CARDIA are probably, at least in part, due to differences in measurement methods. Especially noteworthy among several differences in risk factor levels by demographic subgroup, were a higher body mass index among black than white women and much higher prevalence of cigarette smoking among persons with no more than a high school education than among those with more education.  相似文献   
67.
BACKGROUND: Reduction of house dust mite allergens in the domestic environment can play an important part in reducing sensitization and in the amelioration of symptoms in atopic individuals. Chemical and physical methods have been tried with varied levels of success. The present paper presents a novel electrostatic way of destroying Der p 1, the major mite allergen. OBJECTIVE: To assess the efficacy of negative Trichel, negative continuous glow, positive pulse and positive continuous glow corona in destroying Der p 1. To determine whether ozone has any effect on the integrity of Der p 1 in the experimental conditions present. METHODS: A simple point-to-plane apparatus was used to irradiate samples of Der p 1 for periods of 1, 15, 30, 45, 60, 120, 180, 240 and 300 min. Controls were exposed to the atmosphere with no corona products present for the equivalent time. The effect of the corona by-product ozone was investigated alone by exposing samples of Der p 1 to molecular ozone for 60 min. Der p 1 concentration was quantified by two-site monoclonal antibody ELISA. RESULTS: High current negative glow resulted in a 67.37% reduction in Der p 1 concentration after 300 min compared with a 50.5% reduction from a low current Trichel regime. High current positive glow corona gave a reduction of 25.22% while a low current positive pulse corona caused a 13.72% reduction after 300 min. All these reductions were statistically significant (P < 0.05) compared with unexposed controls. Negative corona always gave greater percentage reductions in Der p 1 concentration for each time exposure investigated. The pattern of percentage reduction follows an exponential rise to maximum relationship in respect to time. Samples of Der p 1 were not affected by exposure to molecular ozone. CONCLUSION: These data indicate corona products to be a powerful new method of destroying Der p 1 allergen that is not dependent on the presence of the oxidizing corona product ozone.  相似文献   
68.
1600例住院病人死亡原因分析   总被引:1,自引:0,他引:1  
[目的 ]探讨 160 0例住院病人的死亡原因及其分布特征 .[方法 ]收集 1995年 1月至 2 0 0 2年12月间 160 0例我院住院死亡病人资料 ,对死亡疾病构成比率、男女主要疾病死亡构成比率、汉族和朝鲜族主要疾病死亡构成比率及年龄构成比率进行统计 .[结果 ] 160 0例死亡病例的死亡原因中脑血管疾病占 2 4 9% ,恶性肿瘤占 2 3 4% ,消化系统疾病占 13 7% ,意外伤害和中毒占 10 3 % ,心血管疾病占9 2 % ;男性与女性主要疾病死亡分布不同 ,两者间有非常显者性差异 ;汉族与朝鲜族主要疾病死亡分布不同 ,两者间亦有非常显者性差异 ;年龄构成比中 61~ 70岁居首位 ,占 2 6 6% ,51~ 60岁占 18 0 % ,41~ 50岁占 16 8% ,71~ 80岁占 15 8% ,3 1~ 40岁占 10 8% .[结论 ]住院死亡的疾病构成因性别及民族不同 ,其分布不同  相似文献   
69.
目的 研究不卧床持续性腹膜透析 (CAPD)患者腹透液中转移生长因子 β1 (TGF β1 )水平及影响因素对腹膜小分子物质清除功能的影响。方法 测定CAPD患者血浆中和腹透液中TGF β1 、IL 6、TNF、CRP(C反应蛋白 )水平 ;同时统计CAPD患者腹透液葡萄糖含量、交换量、次数、留腹时间及腹膜炎次数 ;计算CAPD患者KpT V、Cpcr。结果 CAPD患者血浆中IL 6、TNF、CRP水平均明显高于正常健康人 ,P <0 .0 5~ 0 .0 1;透析第 12月 (KpT V +Cpcr) 2较第 3月下降超过 10 %的CAPD患者其腹透液中TGF β1、IL 6、TNF、CRP、葡萄糖浓度、腹膜炎次数均较对照组明显升高 ,P <0 .0 5~ 0 .0 1;腹透液中TGF β1 与IL 6、TNF、CRP、腹透液中葡萄糖浓度呈正相关 ,P <0 ..0 5~ 0 .0 1,与腹膜炎次数无关 ;腹透液中CRP与葡萄糖浓度、腹膜炎次数呈正相关 ,P <0 .0 5~ 0 .0 1,与腹膜交换量、次数、留腹时间无关。结论 CAPD患者体内确实存在慢性炎症状态 ,其炎症标志性因子CRP与腹透液葡萄糖浓度、腹膜炎次数有关 ,CAPD患者腹膜物质转运功能丧失与TGF β1 、IL 6、TNF、CRP升高有关。  相似文献   
70.
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