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991.
Objectives   To determine if detection of IgM and IgG antibodies against mycobacterial antigen A60, together with the Mantoux tuberculin skin test (TST), could be used in the diagnosis of tuberculous pleurisy (TP) in BCG-vaccinated cases.
Methods   We investigated 125 BCG-vaccinated patients with pleural effusion. Of these, 88 had TP and 37 had non-tuberculous pleurisy (NTP). TST and anti-A60 IgM and IgG measurements by ELISA were performed in the sera and pleural effusions of both groups.
Results   Cut-off values, in optical density, for serum anti-A60 IgM, pleural fluid anti-A60 IgM, serum anti-A60 IgG and pleural fluid anti-A60 IgG were defined as 0.624, 0.614, 0.464, and 0.613, respectively. TP patients had higher IgG and IgM levels in the serum ( P  < 0.001 and P  < 0.05, respectively) and pleural effusion ( P  < 0.001 and P  < 0.001, respectively). Regardless of the diagnosis, IgG and IgM levels were higher in the sera ( P  < 0.001 and P  < 0.05, respectively) and pleural effusions ( P  < 0.001 and P  < 0.001, respectively) of TST-positive cases, and serum and pleural fluid IgM levels were higher ( P  < 0.001 and P  < 0.001, respectively) in the TST-positive TP cases. Sensitivity and specificity of TST were 65% and 68%, respectively. As a single parameter, pleural fluid anti-A60 IgM had the highest sensitivity (77%) and specificity (94%) in patients with negative TST.
Conclusion   We suggest that in populations where tuberculosis prevalence is high and BCG vaccination is common, pleural fluid anti-A60 IgM can facilitate the diagnosis of TP.  相似文献   
992.
Summary The purpose of this study was to evaluate the effects of age on dynamic muscle attributes of the knee extensors and flexors in postmenopausal women. Young healthy women (3rd decade,n = 15; 4th decade,n = 5) and older healthy women (6th decade,n = 9; 7th decade,n = 6) were tested at six angular velocities from 60° · s–1 to 400° · s–1. The 3rd and 4th decade groups produced greater extensor and flexor values for strength related variables at all angular velocities (peak torque, angle specific torque, work, power) than both the 6th and 7th decade groups (P<0.05). However, relative changes in these variables, with increments in angular velocity, were equivalent among the groups. Analysis of the flexor: extensor ratios for these variables demonstrated a differential loss in flexor function with increased age, perhaps indicative of type II motor unit loss or muscle fibre atrophy. It is suggested that such changes may be present even within 4th decade subjects.  相似文献   
993.
 Eye movement responses were obtained from six normal subjects exposed to randomly ordered rightwards/leftwards linear acceleration steps of 0.05 g, 0.1 g or 0.24 g amplitude and 650 ms duration along the inter-aural axis. With the instruction to gaze passively into the darkness, compensatory nystagmus was evoked with slow-phase velocity sensitivity of 49° s−1 g −1. When subjects viewed earth-fixed targets at 30 cm, 60 cm or 280 cm, eye movements at 130 ms from motion onset were proportional to acceleration and inversely proportional to target distance, before the onset of visually guided eye movements. Our results show that a modulation with viewing distances of the earliest human otolith-ocular reflexes occurs in the presence of pure linear acceleration. However, full compensation was not attained for the nearer targets and higher accelerations. Received: 31 January 1996 / Accepted: 30 September 1996  相似文献   
994.
BACKGROUND: Asthma is a common chronic disease and information on its management practices at the community level is helpful in identifying problems and improving asthma care. OBJECTIVE: To assess the severity status and management of the asthma symptom of wheeze of children at the community level in Hong Kong (HK) and Guangzhou (GZ). METHODS: Cross-sectional study of children aged 10 years using the International Study of Asthma and Allergic disease in Childhood (ISAAC Phase II protocol). Asthma management and lung function were assessed in 178 (98 from HK and 80 from GZ) randomly selected children with wheeze over the past 12 months. RESULTS: Eighty-three percent, 11%, 6% and 0% of children suffered from intermittent, mild persistent, moderate persistent and severe persistent asthma, respectively, according to the frequency of their symptoms. Addition of spirometric parameter only changed the asthma severity classification in 2.8% of children. Medications were used by 30.6% and 71.3% of children for wheeze in HK and GZ, respectively. In HK, inhaled beta(2)-agonist (73.3% among the drug users) was the commonest medication used followed by inhaled corticosteroid (ICS) (23.3%). In GZ, inhaled beta(2)-agonist was used by 75.4% of children, but use of ICS (26.3%), oral beta(2)-agonist (26.3%), oral theophylline (45.6%), oral ketotifen (36.8%) and oral steroid (35.1%) were also common. ICS was only used by 11.4% of children with persistent asthma. Ten percent and 18.7% of children in HK and GZ, respectively, had emergency department visits, while 16.3% and 11.6% of children in HK and GZ, respectively, had missed school secondary to asthma over the past 1 year. CONCLUSIONS: Most children in the community had intermittent asthma and addition of lung function to symptoms did not significantly affect classification of asthma severity. Significant morbidity was seen even in this group of children with mostly intermittent and mild persistent asthma.  相似文献   
995.
Dyspnea, the clinical term for shortness of breath, is the primary symptom and an important outcome measure in evaluations of patients with lung disease. It is a subjective symptom that has proved difficult to quantify. Many dyspnea measures are available, yet it is difficult, based on the existing literature, to determine the most reliable and valid. In this study, we evaluated 6 measures of dyspnea for reliability and validity: (a) Baseline Dyspnea Index (BDI) and Transition Dyspnea Index, (b) UCSD Shortness of Breath Questionnaire (SOBQ), (c) American Thoracic Society Dyspnea Scale, (d) Oxygen Cost Diagram, (e) Visual Analog Scale, and (f) Borg Scale. Subjects were 143 patients (74 women and 69 men) with obstructive lung disease, ages 40 to 86, FEV., 0.36 to 3.53 L, FVC 1.07 to 5.74 L. Dyspnea measures were assessed for test-retest reliability, internal consistency, interrater reliability, and construct validity (i.e.. correlations among dyspnea measures and correlations of dyspnea measures with exercise tolerance, health-related quality of life, lung function, anxiety, and depression). Results suggest that the SOBQ and BDI demonstrated the highest levels of reliability and validity among the dyspnea measures examined. This research was supported by University of California Tobacco Related Disease Research Program Grant 2RT026S, National Heart. Lung, and Blood Institute Grant HL 34732 to Robert M. Kaplan, and National Institutes of Health NHLBI Preventive Pulmonary Academic Award No. HL02215 to Andrew L. Ries.  相似文献   
996.
本实验观察慢性缺氧幼猪(Ch组)和对照组(C组)对急性缺氧的血流动力学反应及组胺H_1、H_2受体阻断剂扑尔敏、甲氰咪呱的作用。急性缺氧可增加肺动脉压(Ppa),Ch组比C组增加明显(前者增加25mmHg、100%;后者增加17mmHg,83.4%)。缺氧时扑尔敏降Ppa的作用亦为Ch组大于C组(Oh组降11mmHg,C组6mmHg)。甲氰咪呱增Ppa的作用两组相近。结果提示:(1)慢性缺氧能增强HPPR;(2)组胺受体参与HPPR调节;(3)慢性缺氧可能使肺动脉H_1受体活性增强,此变化可能与HPPR增强有关。  相似文献   
997.
目的研究一氧化氮(NO)在缺氧性肺动脉高压(HPH)发病中的作用。方法用烟酰胺腺嘌呤二核苷酸磷酸—黄递酶(NicotinamideAdenineDinucleotidePhosphateDiaphorase,NADPHd)和免疫组化ABC方法检测原生型和诱生型一氧化氮合酶(cNOS、iNOS)在正常和缺氧大鼠肺内的表达和分布,同时观察左旋精氨酸(Larg)和亚硝基左旋精氨甲酯(LNAME)对正常和缺氧大鼠肺循环的影响。结果HPH组,NADPHd阳性反应见于大血管内皮、平滑肌、支气管粘膜上皮及小血管内皮和平滑肌中,而后者在正常时未见阳性反应;cNOS在肺血管内皮和支气管粘膜上皮中的表达明显减弱,甚至消失,而正常时不表达iNOS的肺血管内皮和血管、支气管平滑肌在HPH组出现了阳性表达;缺氧时补充Larg和LNAME,与单纯缺氧相比,对右心室肥大和肺血管重建无影响。结论缺氧时cNOS被抑制,可能对HPH的形成具有一定的作用;而iNOS的诱导表达,则可能对HPH的形成具有阻止作用。  相似文献   
998.
输精管结扎家兔自身免疫反应的实验研究   总被引:3,自引:0,他引:3  
33只成年雄兔行双侧输精管结扎手术后,进行连续12个月的免疫学观察。7只同龄雄兔作为空白对照。结果表明,间接血凝试验69.7%结扎组家兔检测出抗精子抗体,滴度范围为1:5~1:1280;间接免疫荧光测定有90.9%的实验组家兔测出抗精子抗体。白细胞粘附抑制实验呈阳性反应者占实验组家兔的43.5%,与对照组比较差异显著。应用PEG光密度和抗补体法测定CIC均里阴性。输精管结扎后第3个月附睾肿胀者占45%,第5—7个月达70%,之后逐渐消退。而与此同时抗精子抗体阳性检出率明显增高,故可推断精子抗原主要经附睾入血,作用于免疫系统导致体液与细胞免疫反应。结扎组家兔胸腺、脾、淋巴结呈明显的增生现象支持这一结论。  相似文献   
999.
Christian  Möller  Per  Juto  Sten  Dreborg Bengt  Björkstén 《Allergy》1984,39(4):291-296
In a study of immunotherapy 41 children with seasonal rhinoconjunctivitis due to deciduous tree pollen allergy were monitored by means of symptom scoring, patient self-evaluation, conjunctival provocation tests and lymphocyte proliferation in vitro to the allergen. The lymphocyte responsiveness to birch pollen decreased significantly during the first year of immunotherapy. However, neither the lymphocyte responsiveness before treatment nor changes in lymphocyte reactivity during the immunotherapy correlated with the clinical efficacy of the therapy as evaluated by changes in symptom scores, self-evaluation or conjunctival provocation test changes in the individual patients. The results indicate the lymphocyte responsiveness to an allergen cannot be used to select patients for immunotherapy, i.e. to predict whether a patient would benefit from immunotherapy or not, or to evaluate the effects of immunotherapy after beginning the treatment. However, lymphocyte proliferation response to an allergen indicates clinical sensitivity.  相似文献   
1000.
The energetics of middle-distance running   总被引:3,自引:0,他引:3  
Summary In order to assess the relative contribution of aerobic processes to running velocity (v), 27 male athletes were selected on the basis of their middle-distance performances over 800, 1500, 3000 or 5000 m, during the 1987 track season. To be selected for study, the average running velocity corresponding to their performances had to be superior to 90% of the best French of the season. Maximum O2 consumption and energy cost of running (C) had been measured within the 2 months preceding the track season, which, together with oxygen consumption at rest allowed us to calculate the maximalv that could be sustained under aerobic conditions: . The treadmill runningv corresponding to a blood lactate of 4 mmol·–1 (v la4), was also calculated. In the whole group, C was significantly related to height (r=–0.43;P<0.03). Neither C nor (with, in this case, the exception of the 3000 m athletes) were correlated to . On the other hand,v a max was significantly correlated to over distances longer than 800 m. These were also correlated tov la4. Howeverv la4 occurred at 87.5% SD 3.3% ofv a max, this relationship was interpreted as being an expression of the correlation betweenv a max and . Calculation ofv a max provided a useful means of analysing the performances. At the level of achievement studied, sustained over 3000 m corresponded tov a max. The shape of the relationship ofv/v a max as a function of the duration of the event raised the question of a possible change in C as a function of v during middle-distance running competitions.  相似文献   
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