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排序方式: 共有1184条查询结果,搜索用时 156 毫秒
1.
目的 了解某设备实验条件下不同位置脉冲X射线电离辐射水平,提出适当的防护建议。方法 采用热释光测量方法,分别在设备舱周围不同方向不同距离布放热释光剂量计,累积一定数量脉冲辐射后进行测量;采用电离室型X、γ剂量率仪(FJ-347A)实时测量工作状态下不同距离处电离辐射剂量率水平。依据《电离辐射防护与辐射源安全基本标准》(GB18871—2002)规定的职业照射人员和公众个人剂量限值提出不同工作位辐射防护建议。结果 热释光剂量计累计接收3 000个脉冲辐射,设备舱外壁0.01~8.98 mGy,顶部0.01~15.67 mGy,距外壁1~12 m之间0.01~2.18 mGy,工作位0 mGy。工作状态下,X射线剂量率仪测得距设备舱外侧壁1~20 m之间空气比释动能率范围0.26~16 mGy/h。结论 热释光剂量计、电离室型剂量率仪测量结果基本一致,说明两种方法均可用于脉冲X射线测量;工作状态下设备舱外近距离处辐射剂量率较高,可通过采取防护措施或者限制人员工作量以满足辐射防护要求。 相似文献
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Rosario Fernández-Plata Rogelio Pérez-Padilla Rodrigo Del Río-Hidalgo Cecilia García-Sancho Laura Gochicoa-Rangel Christian Rodríguez-Hernández Luis Torre-Bouscoulet David Martínez-Briseño 《Archivos de bronconeumología》2019,55(10):513-518
IntroductionPeople with Down syndrome (DS) have high respiratory morbidity, evaluating their respiratory health with standardized, objective tests is desirable. Thus, the objective of this study was to evaluate the technical quality of Pulmonary Function Tests (PFTs) to determine which ones are most suitable for this population.MethodsParticipants included children, teenagers and adults with DS, 5 years of age or older (n = 302). The technical quality of the impulse oscillometry system (IOS), forced spirometry, lung-diffusing capacity for carbon monoxide (DLCO), and 6-min walk test (6MWT) were analyzed by age group. Capnography and pulse oximetry were included in the study. Technical quality was determined on the basis of current international PFTs standards.ResultsFifty-one percent of participants were males. A total of 184 participants (71%) who completed the IOS fulfilled the quality criteria, while 210 (70%) completed the 6MWT. Performance on forced spirometry and DLCO was poor. All pulse oximetries and 96% percent heart rates obtained had good quality, but exhaled carbon dioxide (PetCO2) and respiratory rate (RR) showed deficient repeatability.ConclusionsIOS appears to be the most reliable instrument for evaluating lung mechanics in individuals with DS. 相似文献
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导致血不利的原因一是不足,即由于气、血、津、液等物质的缺乏致无源行血;一是不通,即水、湿、痰、饮、瘀、食积、火郁、内风、外伤等病理因素阻滞,致血行不畅。血瘀经脉之内,则水亦瘀积脉中,致脉络胀满,形成水肿。乳腺癌术后患者,金刃本已损伤血脉,术后的放疗、化疗又属祛邪之法,故机体元气受损,气虚无力行血,血运行不畅,导致患侧上肢水肿。故治疗乳腺癌相关淋巴水肿时,应当血水同治,即活血利水之法要贯穿始终。先病血而后病水者,可以活血化瘀为主,利水为辅;先病水后病血者,则以利水消肿为主,酌加活血养血之品。但需要注意的是:①临证时切不可拘泥于单纯的活血利水法,而忽视乳腺癌相关淋巴水肿(breast cancer related lymphedema,BCRL)患者机体本身的状况。②临证勿忽视五脏与血、水的关系,以及肺、脾、肾、三焦与水肿的内在关系。③可多种方法联合运用,审证求因,标本同治。BCRL术后宜补气活血,通脉利水;术后兼化疗者可疏肝健脾、利水消肿;早期可在活血利水基础上,侧重利湿消肿,后期多湿聚为痰,治疗侧重化痰软坚。 相似文献
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论《金匮要略》基本学术思想及辨病与辨证——从《脏腑经络先后病脉证第一》谈起 总被引:1,自引:0,他引:1
张清苓 《北京中医药大学学报》1998,(4)
研究《金匮要略》的重点应该放在对于各种疾病的辨证论治上,而不是某些证或某些方。这里涉及到如何看待病与证以及辨病与辨证的关系。以《金匮要略》的基本学术思想立论,从四个方面阐述了在整体论思想指导下的辨证论治体系,首先注重的是病;辨证方法的确立是由在发病学上具有不同性质特点的疾病所决定的;四诊所得的各种临床信息是为了辨病然后辨证;只有正确把握病与证的关系,才有可能真正理解和掌握“治未病”的实质。 相似文献
7.
Examined are several measures currently used in the assessment of child abuse, sexual abuse, and trauma. These measures include
structured clinical interviews, self report measures, screening inventory, symptom checklist, and some measures that include
decision making properties. Issues and implications for clinical practice are explored. 相似文献
8.
高原低氧对大鼠学习记忆影响的实验研究 总被引:4,自引:1,他引:3
目的:研究高原低氧环境对大鼠学习记忆的影响。方法:利用新生大鼠低氧模型和胎鼠低氧模型,采用爬杆实验和Morris水迷宫实验进行检测.结果:爬杆实验中习得的速度减慢,消退速度加快。Morris水迷宫实验中逃避潜伏期延长,撤除平台后跨越平台次数减少。结论:高原低氧环境下大鼠的学习记忆能力受到抑制,可能与长期低氧后海马NMDA受体数量和功能的下降有关。 相似文献
9.
Birthweight is an important indicator of child survival. Appropriate and timely care of a newborn specially if he is born
with low birthweight is important but this is difficult in developing countries since most of the deliveries are conducted
at home where adequate facilities to weigh a new born does not exist. This study was conducted to find out a surrogate which
could efficiently be used for detecting low birthweight babies at birth when no weighing machine is around. In this study
41% of the newborn babies were found to weigh less than 2,500 gm at birth. Out of this about 52% were females. The mean chest,
thigh and mid-arm circumference at birth for males were 30.89 cm, 15.06 cm and 9.27 cm respectively with standard deviations
of 1.83 cm, 1.30 cm and 1.04 cm. Corresponding figures for female babies were 30.69 cm, 15.14 cm and 9.25 cm respectively
with standard deviations of 2.08 cm, 1.70 cm and 1.16 cm. Correlation co-efficient between normal birthweight and the chest,
thigh and mid-arm circumference were 0.867, 0.845 and 0.842 respectively. A liner regression analysis showed that a chest
circumference of 30.14 cm, a thigh circumference of 14.56 cm and a mid-arm circumference of 8.90 cm corresponded well with
a birthweight of 2,500 gm. On this basis sensitivity, specificity and predictive values of the chest circumference was better
than the other two measurements. However, the mid-arm circumference was observed to be more reliable than the other two measurements
for detecting birthweight less than 2,000 gm. A home made measuring tape has been devised on this basis to detect brithweights
with cut-off values for 2,500 gm, 2,000 gm to 2,500 gm and 2,000 gm in different shades of colour for illiterate birth attendants. 相似文献
10.
Vladimir Mironov Martin A. Hritz Joseph C. LaManna Antal G. Hudetz Sami I. Harik 《Brain research》1994,660(1)
We performed 3-dimensional studies of vascular casts of the microvasculature of the cerebral cortex of rats that were exposed to three weeks of hypobaric hypoxia and of control rats. Scanning electron microscopy of the casts gave the qualitative impression of increased vascularity of the cerebral cortex, particularly the deeper layers, in hypoxic rats. Quantitative analysis of capillary segment lengths revealed a significant shift in the frequency distribution to longer lengths (from 77 ± 8 to 90 ± 14 μm) in the deep, but not in the superficial, layers of the cerebral cortex of hypoxic rats. These findings agree with previous results reporting increased capillary density in the brain after exposure to prolonged hypobaric hypoxia and suggest that capillary segment elongation plays a role in the increased capillary density in the deeper layers of the cerebral cortex. 相似文献