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71.
目的 了解血清涎液化糖链抗原(KL-6)在常见结缔组织病(CTD)并发肺间质病变(ILD)患者中的表达水平及其临床意义。方法 选取2021年4~11月蚌埠医学院第一附属医院收治的187例CTD患者为研究对象,按照结缔组织病有无肺间质病变分为结缔组织病并发肺间质病变(CTD-ILD)组116例,结缔组织病无肺间质病变(CTD-NILD)组71例;选取41例同期本院体检健康者为对照组。在CTD-ILD组中,根据肺高分辨CT(HRCT)表现分为急性组和慢性组;根据HRCT显示的ILD累及范围进行分级(1级,累及范围≤25%;2级,25%<累及范围≤50%;3级,50%<累及范围≤75%;4级,75%<累及范围≤100%);随后根据CTD-ILD患者是否合并有肺部感染分为有肺部感染组和无肺部感染组。采用乳胶凝集法测定血清KL-6水平,比较不同分组血清KL-6水平差异。结果 CTD-ILD组血清KL-6水平高于CTD-NILD组和对照组,差异有统计学意义(P<0.05)。CTD-ILD患者血清KL-6水平在急性组高于慢性组(P<0.05),在有肺部感染组和无肺部感染...  相似文献   
72.
南柴胡粗多糖经糖腈乙酰酯化后采用高分辨毛细管气相色谱分析,发现南柴胡粗多糖主要由L-阿拉伯糖、核糖、D-木糖、D-甘露糖、D-葡萄糖、D-半乳糖等单糖组成,校正因子法测得它们的摩尔比为0.106:2.652:4.070:0.519:0.930:2.518。  相似文献   
73.
脑梗塞患者治疗时间延误原因及对策   总被引:5,自引:0,他引:5  
为探讨脑梗塞患者治疗时间的延误原因和对策,对河北、内蒙古部分地区脑梗塞患者治疗时间延误的原因进行了调查分析。共调查了脑梗塞患者1048例,在6小时内接受治疗的人数为326例,占31.11%;在24小时内,接受治疗的人数为566例,占54.01%;在25小时后,接受治疗的人数为482例,占45.99%。脑梗塞患者治疗延误时间为23.55小时,其院前的延误时间为21.49小时,占91.25%,院后的延误时间为2.06小时,占8.75%。调查发现,对脑梗塞患者实施早期治疗,必须在社区内进一步加强脑梗塞症状学和及早诊治意义的科普教育;提高医务人员对脑梗塞诊治水平和治疗紧迫性的认识,建立和完善医院的快速反应系统。只有这样,脑梗塞的早期治疗,才会有根本性的改善  相似文献   
74.
ARIMA模型在医院卫生消耗材料需求量预测中的应用   总被引:8,自引:1,他引:7  
目的 阐述ARIMA模型拟合时间序列的方法和步骤,并将其应用于医院卫生消耗材料需求量的预测,为医院设备管理人员提供决策依据。方法 利用SAS软件系统,求解适宜的ARIMA模型,据所得误差评价预测效果。结果 通过对3种卫生消耗材料需求量的预测,相对误差在10%左右,预测效果较为可靠。结论 医院卫生消耗材料需求量的近期预测中引入时间序列的ARIMA模型分析方法,能够对实际工作产生积极的指导意义。  相似文献   
75.
目的 探讨女工二硫化碳(CS2)接触水平与胚胎早期发育障碍之间的剂量-反应关系。方法 前瞻观察生育女工妊娠所需的月 经周期数;收集每个月经周期胚胎植入期尿样,检测绒毛膜促性腺激素含量;监测女工作业地点CS2浓度。结果 257名接触组经临床确诊妊娠的女工,各月经周期妊娠机率低于366名对照组女工,时间妊娠率随女工CS2接触水平(CS2接触浓度以CS2接触工龄)升高而降低:妊娠率=0.7033-0.0  相似文献   
76.
目的 探讨2种常用的MR血管成像方法对正常肺动脉图像质量的影响及Gd-DTPA知其中的作用。材料和方法:用1.0Tesla超导TRI系统,体线圈技术,随机选择无人心肺疾患志愿者46例,行2D turbo FLASH和/或3D FISP肺部MRA检查共113次,行Gd-DTPA增强后2D turbl FLASH和/或3D FISP扫描共47次。计算机测量肺动脉和背景噪声的信号强度,计算出肺动脉的信噪  相似文献   
77.
Mechanisms underlying and controlling resolution and perception in working memory are studied by means of a pulse-coupled network model. It is shown that the adaptivity, i.e. the degree to which previous activity affects the ability to fire, of the excitatory units can control several aspects of the network dynamics in a coordinated way to enable multiple items to be resolved and perceived in working memory. One basic aspect is the complexity of the dynamics that regulates the temporal resolution of several items. The slow NMDA-receptor-mediated component of synaptic couplings to excitatory units facilitates successive activations of a given item. The dimension of the activated subspace of the complete available neural representation space is gradually decreased as adaptivity is reduced. It is also shown that the formation of perception by sufficiently intense and coherent activation of different features of an object can be controlled concurrently with resolution by the adaptivity. The mechanisms derived can account for the observed capacity of working memory with respect to number of items consciously resolved and also for the observed temporal separation of different items. Numerous observations link neuromodulators to cognitive functions and to various brain disorders involving working memory. Based on the influence of various neuromodulators on neuronal adaptivity, the model can also account for neuromodulatory regulation of working memory functions.  相似文献   
78.
OBJECTIVE: To describe the time trend of mortality rates of cerebrovascular diseases (CVD) in Hong Kong for the period of 1976 to 1995, and to compare them with those in the more developed countries around the world. METHODS: Mortality rates of CVD were standardized directly using world standard population in 1961. Annual percent changes of mortality rates of CVD were estimated with a non-linear regression. Birth-cohort analysis was carried out at an interval of five-year of age to compare their age-specific mortality rates of CVD in different birth cohorts. Time trend of cause-specific mortality rates of CVD both in males and females was fitted with a simple linear regression model. RESULTS: Considerable downward trend of CVD mortality was observed during the past twenty years. Mortality rates among men and women decreased by 50.96% and 37.85% in 1995, as compared to those in 1976, respectively. Although in general, a greater trend in CVD mortality was observed during the last 10 years, as compared with that in the previous 10 years, an annual increase in CVD mortality of 1.34% was found among males aged 35 to 44 years during the latter 10 years. CVD mortality for both males and females decreased steadily by 1% per year. CVD mortality for females will catch up with that for males by the year of 2013, if such a trend continues. Birth-cohort analysis showed that those born more recently at the same age-group had lower mortality of CVD (except for those born after 1955). Data from hospital admission showed that improvement in the treatment for CVD could have contributed partly to the decrease in its mortality. CONCLUSION: Time trend of mortality of CVD in Hong Kong was similar to that in many other economically developed areas around the world.  相似文献   
79.
槲皮素对培养人视网膜色素上皮细胞增生及DNA合成的影响   总被引:3,自引:0,他引:3  
目的研究槲皮素(quercetin, QUE)对培养人视网膜色素上皮(retinal pigment epithelium, RPE)细胞增生和DNA合成以及对表皮生长因子(epidermal growth factor, EGF)促RPE细胞增生和DNA合成作用的影响。方法用细胞计数和3H-胸腺嘧啶核苷(3H-thymidine, 3H-TdR)掺入方法,观察不同浓度(200、100、50、1μmol/L)的QUE和最大浓度的QUE(200μmol/L)在不同作用时间(24-168小时),分别单独或与EGF共同作用时,对RPE细胞增生及DNA合成的影响,排除着色的死细胞,用活细胞计数法判断药物的细胞毒性作用。结果QUE 200μmol/L具有最强的抑制效应,48小时时抑制效应已明显出现,96小时时抑制达到高峰。与QUE单独作用相比,QUE对EGF的促RPE细胞增生效应能产生更强的抑制。QUE无细胞毒性作用,各实验组细胞活力均在85.00%以上。结论QUE以剂量依赖和时间依赖的方式抑制RPE细胞的增生,尤其是由EGF刺激的增生,并且对培养的RPE细胞无细胞毒作用。(中华眼底病杂志,1999,15:27-29)  相似文献   
80.
Summary To investigate the influence of time of day on sympathoadrenal and pressor reactivity during exercise, eight trained men [age, mean (SD), 24 (0.5) years; maximal oxygen uptake ( ), 4.7 l·min–1] performed bouts of static (ST) and dynamic (DYN) exercise at 0600–0800 hours (AM) and at 1600–1800 hours (PM). The ST protocol utilized a two-leg isometric contraction at 30% maximum voluntary contraction until failure, and was monitored by a strain gauge interfaced from a leg extension apparatus to a computer. Heart rate (fc) and blood pressure ( ) responses were recorded at rest, after 1 and 2 min of exercise, and at failure. Epinephrine (EPI) and norepinephrine (NE) levels were recorded before exercise, and after 2 min of exercise. The DYN exercise protocol involved stationary. cycling for consecutive 6-min periods at 60% and 80% . fc, , EPI, and NE were recorded before exercise and at each workload. No differences were observed in preexercise or exercise fc under any condition. Preexercise did not differ under any condition. The response to DYN was significantly higher at 80% during PM only. was significantly higher in ST-PM at 1 min, 2 min, and failure. Elevations in both systolic and diastolic P a contributed to this difference. Preexercise EPI-ST-AM was significantly elevated vs PM, but no other preexercise data were significantly different. Absolute exercise levels were significantly higher for EPIST-PM vs AM only, but the percentage change from baseline was significantly (P<0.01) higher in ST-PM for EPI (+231% PM vs + 32% AM) and NE (+352% PM vs +216% AM). The EPI and NE responses to DYN exercise tended to be higher in AM, but were not significantly different. These data support a time of day pattern in sympathoadrenal and pressor reactivity to exercise that is dependent on the type of activity involved but independent of baseline patterns.  相似文献   
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