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71.
Two cases of small-cell carcinoma of the ovary in the ascitic fluid and peritoneal/pelvic washings of a 30- and 28-yr-old woman, respectively, are presented and discussed. Smear preparations from the ascitic fluid showed loose clusters and single malignant cells with scant cytoplasm and nuclei with smooth to irregular nuclear membranes, granular chromatin, and small nucleoli. In the second case peritoneal/pelvic washing specimens contained clusters and single malignant cells with a moderate amount of cytoplasm and nuclei with smooth nuclear membranes, granular, clumped chromatin, and prominent nucleoli. Histology confirmed the diagnosis of small-cell carcinoma of the ovary. These are the first reported cases of this rare ovarian neoplasm present on fluid cytology. Its differentiation from other small-cell neoplasms on peritoneal fluid cytology from young women is discussed. Diagn Cytopathol 1994; 11:266–270. © 1994 Wiley-Liss, Inc.  相似文献   
72.
血管内皮细胞衬于血管腔的表面,是血流机械应力的主要感受者。切应力可以直接调节内皮细胞生物活性物质的合成和分泌,其中包括诱导内皮细胞生成IL-8,而且IL-8的生成量与切应力作用时间有关。为阐明内皮细胞IL-8的生成除了与切应力的作用时间有关外还与切应力的强度有关,我们用不同强度的流体切应力(2.09、4.61、6.19、8.51、10.50、12.59、14.41、17.22、18.32dyne/cm^2)处理培养的人脐静脉内皮细胞,然后采用双抗体夹心ABC-ELISA技术检测内皮细胞IL-8蛋白质的生成。结果显示:未用切应力处理的内皮细胞只有极少量的IL-8蛋白质生成;切应力处理内皮细胞后,低切应力(2.09dyne/cm^2)时IL-8蛋白质生成量明显增加,约为高切应力(18.32dyne/cm^2)时IL-8蛋白质生成量的6(作用5h)或7倍(作用6h)。IL-8蛋白质生成量与内皮细胞所施加的切应力强度呈反变关系;直线回归方程:5h时为y=760.12—36.06x,相关系数7=-O.978;6h时为y=781.87—36.66x,相关系数7=-O.980。式中:y为切应力作用下内皮细胞IL-8的生成量;x为施加于内皮细胞的切应力强度(dyne/cm^2)。不同的切应力作用时间(5h、6h)均表现出相同的IL-8蛋白质生成量随切应力强度的变化规律。提示流体切应力诱导内皮细胞生成IL-8的量,不仅与切应力的作用时间有关,而且IL-8的生成量与切应力强度有关。流体低切应力诱导内皮细胞IL-8的生成量急剧增高,可能在急性炎症和动脉粥样硬化的发生、发展过程中具有重要作用。  相似文献   
73.
We measured the aerobic capacity, sweat rate and fluid intake of trained athletes during outdoor exercise and examined the relationship between aerobic capacity and thermoregulatory responses at high ambient temperatures. The maximal aerobic capacity ( ) of the subjects, nine male baseball players of college age, was determined by maximal exercise tests on a cycle ergometer. The subjects practised baseball regularly without drinking fluids from 1330 to 1530 hours. After 30 min rest, they played a baseball game with free access to a sports drink at 15°C from 1600 to 1830 hours. At a mean ambient temperature of 36.7 (SEM 0.2)°C, the mean percentage of body mass loss (m b) and increase of oral temperature (T o) from 1330 to 1530 hours was 3.47 (SEM 0.12)% and 0.81 (SEM 0.14)°C, respectively. The sweat loss from 1330 to 1830 hours was 56.53 (SEM 1.56)ml · kg–1 of body mass (M b) while the mean fluid consumption was 44.78 (SEM 2.39)ml · kg–1 ofm b, with recovery of 76.08 (SEM 2.81)% of sweat loss. The was significantly inversely correlated withm b, fluid intake and rehydration amount, but showed no correlation withT o. These results would suggest that at a given exercise intensity in subjects with a higher aerobic capacity body temperature is maintained with a lower sweating rate than that in subjects with a lower aerobic capacity.  相似文献   
74.
Recent evidence shows that circulating leukocytes respond not only to humoral inflammatory mediators but also to fluid stresses. Application of fluid shear stress (of the order of 1–10 cm2 to fresh migrating leukocytes leads to initial retraction of pseudopods, an important step to facilitate normal passage of leukocytes through the microcirculation and to prevent spreading on the endothelium. The ability to respond to fluid shear stress, however, may be regulated under different physiological conditions. In the current study, we examine the role of integrins in the fluid shear response as measured by pseudopod retraction with the use of antibodies against human neutrophil 1 and 2 integrins. Neutrophils adhering via 2 integrins exhibit normal ability to project pseudopods and to migrate. Such cells show normal response to fluid shear with rapid pseudopod retraction. In contrast, attachment via 1 integrins leads to firmly adhesive leukocytes, spreading and almost no cell migration. Such leukocytes exhibit a significantly attenuated ability for pseudopod retraction under fluid shear. These results suggest that integrins may serve as a regulating mechanism for fluid shear response in human leukocytes. Attachment via 1 integrins may lead to an abolishment of the fluid shear response. © 2002 Biomedical Engineering Society. PAC2002: 8716-b, 8719Tt  相似文献   
75.
Context: Muscle fatigue is generally categorized in 2 ways: that caused by peripheral weakness (peripheral fatigue) and that caused by a progressive failure of voluntary neural drive (central fatigue). Numerous variables have been studied in conjunction with fatigue protocols, including postural stability, maximum voluntary contraction force, and reaction time. When torque recordings fall below 50% of a maximum voluntary contraction, the muscle is described as fatigued, but whether this value is a good indicator of fatigue has not been studied.Objective: To compare the effects of 2 ankle musculature fatigue protocols (30% and 50%) on the duration of postural stability dysfunction.Design: To assess differences between the 30% and 50% fatigue protocols, we calculated a 1 between-groups factor (subjects) and 2 within-groups factors (fatigue, test) analysis of variance.Setting: E.J. Nutter Athletic Training Facility.Patients or Other Participants: Twenty subjects (10 men, 10 women; age = 21.15 ± 2.23 years; height = 172.97 ± 9.86 cm; mass = 70.62 ± 14.60 kg) volunteered for this study. Subjects had no history of lower extremity injury, vestibular or balance disorders, functional ankle instability, or head injury in the past 6 months.Intervention(s): On separate days, subjects performed isokinetic fatiguing contractions of the plantar flexors and dorsiflexors in a 30% protocol (70% decrease in strength) and a 50% protocol (50% decrease in strength).Main Outcome Measure(s): Baseline and postfatigue postural stability scores were determined before and after the isokinetic fatiguing contractions. Plantar-flexion peak-torque measurements were obtained for the 2 fatiguing protocols. Three prefatigue and 12 postfatigue postural stability trials were recorded. Velocities for testing were 60°/s for plantar flexion and 120°/s for dorsiflexion.Results: Sway velocity was significantly greater when the ankle was fatigued to 30% (1.56°/s) than in the 50% condition (1.36°/s). For the 30% protocol, sway was significantly impaired when the pretest condition (1.19°/s) was compared with posttest trial 1 (2.34°/s), trial 2 (2.37°/s), and trial 3 (1.71°/s). For the 50% protocol, sway was significantly impaired when the pretest condition (1.27°/s) was compared with posttest trial 1 (2.02°/s).Conclusions: The 30% fatigue protocol resulted in significantly longer impairment of postural stability than the 50% protocol. Because the 30% protocol resulted in a greater effect but was relatively short-lived (approximately 75 to 90 s), it is more useful for research purposes.  相似文献   
76.
血管内皮细胞位于血流和血管壁之间,除受化学因素的调节外还受力学因素的影响。切应力可通过刺激相应的力学感受系统来调节内皮细胞某些基因的表达,其中包括诱导内皮细胞表达IL- 8。为了阐明MAPK信号途径中的ERK1/ 2信号通路是否参与调控低切应力上调人脐静脉内皮细胞IL- 8基因表达,采用Western blot分析了低切应力(4.2 0 dyne/ cm2 )处理不同时间内皮细胞ERK1/ 2的磷酸化水平及TPK抑制剂Genistein,MEK抑制剂PD980 5 9对其磷酸化的影响;采用定量RT- PCR检测内皮细胞经低切应力刺激或给予阻断剂后再行切应力刺激等处理后IL- 8基因的表达。结果显示:(1)低切应力处理可引起内皮细胞ERK1/ 2蛋白磷酸化水平上调,其磷酸化水平与切应力作用时间有关,具有快速、双向性的特点(在刺激10 min时达到高峰,2 h左右降至未刺激水平) ,阻断剂Genistein和PD980 5 9处理后,ERK1/ 2磷酸化水平与低切应力刺激10 min比较明显降低;(2 )阻断剂Genistein,PD980 5 9可显著抑制低切应力所致的内皮细胞IL- 8m RNA上调。结果表明低切应力可通过ERK1/ 2信号途径上调人脐静脉内皮细胞IL- 8基因的表达。  相似文献   
77.
Summary The rhythm of renal sodium and potassium excretion was measured in 4-h-intervals in 12 subjects. Each person exhibited clear circadian variations of each variable with a maximum between 8 a.m. and 4 p.m. In each subject and for both circadian rhythms the oscillation mean was correlated to the range of oscillation (amplitude).Increase in sodium or potassium excretion during 1 day resulted in an increase of oscillation range. The oscillation means of sodium and potassium periodicity did not correlate.The properties of biological control systems with oscillating correcting variables are comparable to those of technical control systems. The significance of circadian rhythm for the control of electrolyte balance is indicated.  相似文献   
78.
假体磨损碎屑颗粒是引起假体一骨界面无菌性炎症和骨溶解而致全关节置换术失败的主要原因之一。磨屑颗粒所诱发的骨溶解须有周围骨组织中成骨细胞分泌足够的骨基质以弥补丢失的骨量,而成骨细胞正常的数量和质量有赖于其来源骨髓祖细胞—骨髓问质干细胞的正常增殖分化能力的维持。为了探讨磨屑钛颗粒对大鼠骨髓间质干细胞(Rat MSCs,rMSCs)产生细胞毒性的可能细胞分子机制,选用健康3月龄SD雄性大鼠,采用Percoll等密度梯度离心法分离获取rMSCs,经体外传代纯化培养后,与不同直径、不同负荷浓度、不同负荷作用时间的钛颗粒悬液共孵育,再采用精准的流室系统对钛颗粒负荷的rMSCs施加一定的流体剪切应力(Fluid shear stress,FSS)后立刻固定细胞,经免疫荧光抗体染色,结合激光共聚焦显微镜技术和图像分析软件定性定量分析rMSCs F—actin表达和DNA含量的变化情况。同时设置相应的未经钛颗粒孵育的rMSCs细胞为对照组细胞。结果显示,切应力作用可上调rMSCs胞内F—actin的表达。亚微(Submieron)直径(0.9μm)的钛颗粒负荷对rMSCs F—actin表达和DNA含量的抑制作用最为显著,并伴有凋亡小体出现;直径为2.7μm的钛颗粒负荷产生的抑制作用略为减弱,而较大直径(6.9μm)的抑制效应最弱。相同条件下,钛颗粒负荷对F—actin的抑制效应有一定的时间和浓度依赖性:以0.1wt%浓度对F—actin表达和DNA含量的抑制效应最为明显,亦有凋亡小体的出现;随着浓度的降低,抑制作用亦减弱,以0.01wt%浓度最弱;随着作用时间的延长,F—actin表达和DNA含量逐渐降低,至实验中的32h达到最低值。提示:磨屑颗粒对rMSCs活力的抑制作用是假体无菌性松动的可能分子机制,对其具体细胞分子机制进行深入研究,必将有助于有效防治假体松动药物的研发应用以及人工关节材料的优化设计,从而为全关节置换术患者真正带来福音。  相似文献   
79.
The Eastern Mediterranean Region (EMR) is experiencing a nutrition transition, characterized by the emergence of overnutrition and micro-nutrient deficiencies. No previous study has comparatively examined nutrient intake in adults across countries in the EMR. This review examined the adequacy of nutrients in adults living in the EMR. Moreover, it analyzed the food balance sheets (FBS) for 1961–2018 to identify the trajectory of energy supply from macro-nutrients in the EMR. A systematic search was conducted from January 2012 to September 2020. Only observational studies were retained with a random sampling design. An assessment of the methodological quality was conducted. Levels of nutrient daily intake and their adequacy compared to the daily reference intake of the Institute of Medicine were reported across the region. No studies were identified for half of the region’s countries. Although nutrient energy intake was satisfactory overall, fat and carbohydrate intake were high. Intake of vitamin D, calcium, potassium, zinc, and magnesium were below that recommended. The analysis of the FBS data allowed for the identification of four linear patterns of trajectories, with countries in the EMR best fitting the ‘high-energy-supply from carbohydrate’ group. This systematic review warrants multi-sectorial commitment to optimize nutrient intake.  相似文献   
80.
Background: Coronavirus disease 2019 (COVID-19) causes not only severe illness but also detrimental effects associated with the lockdown measures. The present study aimed to evaluate reported lifestyle changes in a cohort of adults in Italy, including physical exercise, food choices, and psychological wellbeing, after two months of lockdown. Methods: A web survey on social media (Facebook and LinkedIn) of 32 multiple-choice questions aiming to evaluate the impact of the national COVID-19 lockdown in a sample of Italian adults. Results: We received 1378 complete responses (women 68.3%, mean age 39.5 ± 12.5 years). The percentage of participants reporting regular exercise decreased during lockdown (52 vs. 56.5%). The vast majority of people continued to consume the three traditional meals per day, but the consumption of meat, fish, and eggs significantly decreased. Women reported more frequent anxiety, sadness, fear, and feelings of insecurity than men. The factors predicting the worst outcome during the lockdown were being a woman, low education and income, gastrointestinal diseases. Conclusion: The lockdown has had a limited impact on food choices and physical exercise in Italian adults of our series, since most of them made an effort to improve their lifestyle. However, women with gastrointestinal diseases reported more frequent negative feelings and poor adaptation to the lockdown.  相似文献   
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