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111.
Objective : To define the individual neonatal response to the artificial surfactant, Exosurf, and factors that may influence the response.
Methodology : Eighty-two consecutive, preterm neonates with respiratory distress syndrome, who received Exosurf at <12h of age were studied. Their response was categorized from the graphical change in the oxygenation index with postnatal age, for 12h after each of two doses of surfactant and assessed independently by two observers. Clinical factors were analysed for their effect on the four pre-defined categories of response, namely: none; mild; good; relapsed; and good: sustained.
Results : Within the first 12h, 11% of the neonates showed no response, 5% a mild response and 84% a good response, but 34% relapsed. By 24h, 6% still showed no response (all died), 11% showed a mild response and 83% a good response, of whom half relapsed. At 24h, no response was significantly associated with low gestational age and asphyxia mild response with less severe lung disease. According to the response there was a gradation in the risk of death during the first week.
Conclusions : The response to Exosurf can be individually and reproducibly categorized and demonstrated that 83% of neonates had a good response but half relapsed. No response was associated with extreme prematurity and asphyxia 相似文献
Methodology : Eighty-two consecutive, preterm neonates with respiratory distress syndrome, who received Exosurf at <12h of age were studied. Their response was categorized from the graphical change in the oxygenation index with postnatal age, for 12h after each of two doses of surfactant and assessed independently by two observers. Clinical factors were analysed for their effect on the four pre-defined categories of response, namely: none; mild; good; relapsed; and good: sustained.
Results : Within the first 12h, 11% of the neonates showed no response, 5% a mild response and 84% a good response, but 34% relapsed. By 24h, 6% still showed no response (all died), 11% showed a mild response and 83% a good response, of whom half relapsed. At 24h, no response was significantly associated with low gestational age and asphyxia mild response with less severe lung disease. According to the response there was a gradation in the risk of death during the first week.
Conclusions : The response to Exosurf can be individually and reproducibly categorized and demonstrated that 83% of neonates had a good response but half relapsed. No response was associated with extreme prematurity and asphyxia 相似文献
112.
A correlation between apoptosis and proliferation in astrocytomas and oligodendrogliomas, but not in glioblastomas, has been previously reported. An index for apoptosis and proliferation was established for each tumor in a series of 20 brain metastases, and its correlation was studied using the Spearman rank correlation test. Apoptosis index (AI) ranged between 1 and 78% (mean ± SD: 11.48 ± 16.4). Proliferation index (PI) ranged between 2.4 and 21% (mean ± SD: 8.23 ± 4.8). When the relationship between AI and PI was studied, a clear correlation was found (r: 0.8965, 95% CI: 0.74–0.95; P < 0.0001). Therefore, it is concluded that a clear correlation exists between proliferation and apoptosis in secondary tumors of the brain. 相似文献
113.
目的:观察丙氨瑞林对子宫内膜癌的治疗作用。方法:对诊刮确诊的17例子宫内膜癌病人,予丙氨瑞林700μg,im,qd×7d,用药前后作性激素测定及组织学检查。结果:绝经妇女用药后血中FSH和LH下降(P<0.01和<0.05),雌二醇、孕酮及睾丸酮变化不明显。其中13例内膜样腺癌用药后有丝分裂指数明显下降(P<0.01),有丝分裂指数变化与癌周内膜之反应有关。呈增生反应癌周内膜癌组织有丝分裂指数下降值明显高于呈萎缩状态癌周内膜。结论:丙氨瑞林治疗子宫内膜癌后能降低FSH和LH水平,对子宫内膜癌尤其是雌激素依赖性内膜癌有一定疗效。 相似文献
114.
To provide better transient performance in controlling robots, a mixed minimum time and quadratic performance index is used. For known and uncertain revolute robot manipulators a conventional optimal control and a robust guaranteed cost control are proposed respectively. Asymptotic stability is also discussed based on the Lyapunov direct method. The proposed robust control is continuous and requires no knowledge of the uncertain system except for bounding functions. 相似文献
115.
羧酸酯酶和羧酸酯酶基因表达量与体质量指数的关系及其基因多态性分析 《首都医科大学学报》2023,44(1):13-19
目的 通过检测健康志愿者的羧酸酯酶1 (carboxylesterase 1,CES1)和羧酸酯酶2 (carboxylesterase 2,CES2)的基因多态性和基因表达水平,探索CES1和CES2在代谢中的作用。方法 从48例健康志愿者获得血样并提取DNA,对DNA进行二代基因测序,并提取总RNA检测基因表达量。使用多元线性回归分析CES1和CES2基因表达量与性别、年龄、体质量指数(body mass index, BMI)的关系。结果 CES1的基因表达量为141.8(72.7,237.8),CES2的基因表达量为74.4(30.8,133.6)。多元线性回归分析中,BMI与CES2的基因表达有关,性别、年龄和BMI与CES1的基因表达无关。发现CES1 20个基因变异,其中10个会引起氨基酸序列改变;发现CES2 6个基因变异,其中2个引起氨基酸序列改变。结论 发现CES2的表达水平与BMI相关,CES1的表达水平与BMI无明显相关,基因预测结果提示CES1的遗传变异可能影响其功能表达。 相似文献
116.
背景 我国人口老龄化形势日益严重,家庭医生签约服务对助推分级诊疗制度建设、建立合理有序就医秩序发挥着重要作用,目前学者对家庭医生签约服务政策的研究主要集中于定性评价,较少有学者利用工具聚焦代表性政策对各篇进行定量评价。目的 定量评价我国中央层面的6篇家庭医生签约服务相关政策,分析政策优劣,在此基础上,提出促进我国家庭医生签约服务高质量发展的对策和措施,助力健康中国战略实施。方法 于2022-04-30,以“家庭医生”为关键词在北大法宝数据库进行全文检索,并在国务院网站进行相关内容检索,检索时限为2015-01-01至今。采用ROSTCM 6.0软件进行文本挖掘,然后以其结果为依据选择其中具有代表性的中央层面家庭医生签约服务相关政策,并基于政策一致性评价(PMC)指数模型对其进行量化评价。结果 依据纳入与排除标准检索获得相关政策32篇,家庭医生签约服务领域排名前5位的高频关键词为“签约服务”(274次)、“健康”(272次)、“医疗”(264次)、“家庭医生”(225次)、“签约”(180次),以其为依据共选择中央层面有代表性的家庭医生签约服务相关政策6篇,分别标记为P1~P6。政策量化... 相似文献
117.
Min Huang 《中国生物医学工程学报(英文版)》1998,(1)
INTRODUCTIONWhenpulsatingbloodflowsthroughtheartery,thearterialwallwilldilateandcontractperiodicallybecauseoftheelasticityofarterialwallandtheperipheralresistance'Thisensuresthecontinuityofbloodflowandthelocalbloodpressurenotchangingtoomuch.Ifthearterialwallispathologicallychanged,causingthechangeoftheelasticityofarterialwall,theperformanceofarterywillbeaffected'Atpresent,thecomplianceiswidelyusedtoevaluatethedistensibilityofarterialwass[1],butitcannotevaluatethetotalperformanceofartery'T… 相似文献
118.
I.P. Witz Margalit Yaakubowicz Ilana Gelernter Y. Hochberg Romema Anavi Maya Ran 《Immunobiology》1984,166(2):131-145
Serum from young normal BALB/c mice was found to contain IgM antibodies able tomediate complement-dependent lysis of certain syngeneic or allogeneic tumor target cells. The titer of such naturally occurring antitumor antibodies (NATA) was found to increase with aging.A longitudinal serological study comparing the cytotoxicity potential of NATA fromnormal and from urethan-treated BALB/c mice was performed. It was found that urethan-treated mice that did not develop primary lung-adenomas within the duration of the experi-ment had significantly lower NATA titers, against one out of 4 target cells assayed, than urethan-treated animals that developed lung adenomas. This difference was evident in two independent experiments. The results suggested that the lower NATA activity of the urethan-treated mice that did not develop tumors existed even before exposure to the carcinogenic insult. This raises the possibility that certain populations could be segregated according to their natural antibody profile into those individuals which will develop primary tumors within a certain period if exposed to a subthreshold amount of carcinogen, and those which will not. 相似文献
119.
T. I. Shklyar 《Bulletin of experimental biology and medicine》1977,84(5):1631-1632
Wounds 1 cm long, down to the cutaneous muscle, were inflicted on rats aged 11 days, 2 months, and 2.5 months in the subscapular region. Nociceptive stimulation was applied to the animals by means of an electric current 48 h after the operation. Mitotic activity was determined in cells of the stratum basale of the skin epithelium adjacent to the wound. Nociceptive stimulation was found to reduce the mitotic index of the cutaneous epithelial cells of the animals of all age groups studied by a considerable degree (by several times). An increase in the mitotic index was observed from the early to the later stages of postnatal ontogeny.Laboratory of Age and Evolutionary Physiology, Voroshilovgrad Pedagogic Institute. Laboratory of Growth and Development, Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 11, pp. 605–606, November, 1977. 相似文献
120.
Ishiguro N Kanehisa H Miyatani M Masuo Y Fukunaga T 《European journal of applied physiology》2005,94(1-2):25-35
This study tested the hypothesis that, as compared to whole-body bioelectrical impedance (BI) analysis, segmental BI analysis can estimate lean body mass (LBM) more accurately in a population with a large difference in muscularity. In addition to whole-body BI, which determines impedance (Z) between the wrist and ankle, two segmental BI analyses which determine the Z value of every body segment in each of (1) the arms, legs and trunk (distal BI) and (2) the upper arms, upper legs and trunk (proximal BI) were applied to a group of 125 male athletes and 75 non-athletes. The subjects were divided into validation and cross-validation groups. Simple and multiple regression analyses were applied to (length)2/Z (BI index) values for the whole-body and each body segment, to develop the prediction equations of LBM measured using air-displacement plethysmography. In the validation group, the SE of estimation was similar in the whole-body (3.4 kg, 5.4%), distal (3.4 kg, 5.5%) and proximal BI (3.3 kg, 5.2%) analyses. However, the whole-body and distal BI analyses produced systematical errors in the estimates of LBM. Moreover, the residuals in the two methods significantly (P<0.05) correlated with the ratios of BI indices of the upper arms and upper legs to those of the arms and legs, respectively, calculated as variables approximating the relative development of lean tissues at the proximal area of limbs. On the other hand, the proximal BI analysis was validated and cross-validated. Thus, the accuracy of estimating LBM was similar in the whole-body and the two segmental BI analyses. However, the prediction equations derived from the use of the whole-body BI index and a combination of the arms, legs and trunk BI indices produced a systematical error relating to the difference between the limb segments in lean tissue development. 相似文献