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51.
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为了寻找能够控制硝普钠释放的控释膜,研究了数种高分子膜的通透性,其中以经过热处理的聚乙烯醇(PVA)膜控制硝普钠释放性能较好。进一步研究了热处理条件对PVA膜通透性的影响,发现只要热处理的温度和时间恰当,就可以获得具有一定通透性的PVA膜。 相似文献
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A. Linneberg I. Hertzum L. L. N. Husemoen N. Johansen T. Jørgensen 《Clinical and experimental allergy》2006,36(6):714-721
BACKGROUND: It has been proposed that alcohol consumption may be one of the lifestyle factors associated with a westernized, urban, and affluent lifestyle contributing to the rise in atopic disease. OBJECTIVE: The aim was to investigate the association between alcohol consumption and atopy (aeroallergen sensitization). METHODS: In 1982, a population-based cross-sectional study of 3608 Danes (79% of the invited), aged 30, 40, 50, and 60 years, was carried out. Information on alcohol consumption was obtained by a questionnaire. Aeroallergen sensitization was defined as a positive test for the detection of specific IgE against a panel of 19 common inhalant allergens in stored serum samples. A total of 3317 subjects with complete information on all variables were included in the analyses. RESULTS: We found a statistically significant association between alcohol consumption and aeroallergen sensitization (independent of the type of alcoholic drink consumed). This association appeared to relate only to those who consumed more than 8 drinks/week. After adjustment for confounders this association was only statistically significant for those who consumed 15-21 drinks/week (adjusted odds ratio 1.8, 95% confidence interval 1.2-2.8). CONCLUSION: In this adult general population, self-reported alcohol consumption was positively associated with aeroallergen sensitization. 相似文献
55.
重视介入性肺减容术的研究 总被引:5,自引:2,他引:3
介入性肺减容术是在外科切除肺减容术和内镜下非外科切除肺减容术的基础上发展起来的。它是一项X线导引下的经导管治疗技术,在靶肺叶经支气管行博来霉素(或无水乙醇)碘油乳剂栓塞的同时并对其近端支气管用骨水泥封堵,可获得稳定的肺纤维化和肺减容,即所谓的功能性肺叶切除。虽然此项介入治疗技术目前仍处于动物实验阶段,但已经显露出其临床应用潜力和广阔的前景。 相似文献
56.
酒精染毒后大鼠睾丸生精小管超微结构的改变 总被引:3,自引:0,他引:3
目的:观察酒精染毒后大鼠睾丸生精小管超微结构的变化。方法:将48只W istar雄性性成熟健康大鼠随机分为对照组(A组)、染毒组(B组),每组24只,B组用50度酒精(6 m l/kg)每天灌胃染毒1次,连续39 d,A组用生理盐水灌胃(6 m l/kg);在第14、27、40 d分别从A、B两组中各处死8只大鼠,取睾丸组织,常规电镜制片,透射电镜观察大鼠睾丸生精小管超微结构。结果:透射电镜发现:对照组各时间段睾丸生精小管超微结构无明显变化,基膜平滑、致密、厚薄均匀,支持细胞胞质丰富、粗面内织网及线粒体较多,核大、核质均匀、核仁清楚,精原细胞与基膜和支持细胞之间连接紧密,紧密连接层次清楚。染毒组第1生精周期末(相当于第14 d)超微结构开始变化;第2、3个生精周期末(分别相当于第27、40 d)超微结构变化最明显,主要表现为:①支持细胞溶酶体增多,线粒体肿胀空泡化,细胞器模糊且数量减少,支持细胞内出现较大空泡,甚至支持细胞出现萎缩;②精原细胞与支持细胞及生精小管的基膜之间出现较多较大空泡;③精原细胞凋亡,凋亡小体边集;④生精小管内的精子有过多的胞质且有大小不一的空泡,尾部断面线粒体排列不整齐、缺失或堆积;⑤紧密连接层次改变、模糊不清;⑥基膜厚薄不均,基膜外胶原组织疏松增厚,成波浪式皱褶,可见基膜断裂。结论:酒精可引起大鼠睾丸生精小管的基膜、紧密连接、支持细胞等超微结构异常,并可引起精原细胞凋亡。 相似文献
57.
A significant decline (34.5%) in the suicide rate occurred in 1984–1988 throughout the USSR. The decline was observed shortly after the introduction of strict restrictions on the sale of alcohol. We tested the hypothesis that the restrictive alcohol policy in the first years of perestroika (June 1985) caused the fall in suicide rates in the former USSR. Data on alcohol consumption, violent death caused by external injury and poisoning (n= 916,315), death due to accidental alcohol poisoning (n= 77,837), suicide (n= 192,305) and death undetermined whether accidentally or purposely (n= 54,253) were analyzed for all former Soviet republics for 1984, 1986, 1988 and 1990. Men were chosen for the analysis, since men are more prone to abuse alcohol than women. Regression analysis with alcohol consumption as the independent variable and suicide rates and violent death rates as dependent variables shows that suicide and alcohol consumption were positively correlated as were violent death and alcohol consumption. In the republics with high alcohol consumption (Slavic and Baltic), suicide rates were also high. In the Caucasian republics, low alcohol consumption was associated with low suicide rates. For most republics, alcohol seems to explain more than 50% of suicides. Alcohol also has considerable explanatory value for violent death. Thus, a restrictive alcohol policy might be a way to reduce suicide and violent death. 相似文献
58.
Summary A pathologic study was undertaken of seven encephalic arteriovenous malformations, including five resected from one to seven days after balloon embolization, one resected 10 days after embolization with polyvinyl alcohol foam (PVA), and a large mesencephalic AVM in a patient who died eight weeks after a series of embolization procedures with PVA and silicone spheres. AVM's resected 6–7 days following balloon embolization showed focal mural and adventitial inflammatory infiltrates and parenchymal (i.e. non-vascular) necrosis of a large portion of one AVM. The AVM examined 7 days post-balloon embolization showed an intraluminal thrombus containing refractile particles surrounded by foreign body giant cells (FBGC's). The AVM removed 10 days after PVA embolotherapy showed mural and perivascular necrosis with infiltration by polymorphonuclear leukocytes. The single autopsy case showed FBGC's surrounding residual PVA, refractile particles deep within vascular walls, and marked mural thickening of AVM channel walls, changes that may represent a response to previous angionecrosis and inflammation at the time of embolization. These findings, the pathogenesis of which is discussed in detail, may help to explain some of the rare complications of iatrogenic embolotherapy with these materials, as well as providing evidence for the basis of their efficacy.Presented in part at the 63rd Annual meeting of the American Association of Neuropathologists, Seattle, Washington, June, 1987 相似文献
59.
H. Mochizuki T. Masaki S. Matsushita K. Kamakura K. Motoyoshi S. Higuchi 《European journal of neurology》2006,13(8):896-900
The pathogenesis of cognitive impairment in alcoholics remains unclear. Previous studies suggested that diffuse white matter atrophy is associated with cognitive impairment in alcoholics. To elucidate this issue, the present study evaluated alcoholics with cognitive impairment using the somatosensory evoked potential (SEP) recovery method, which is suitable for detecting subtle dysfunction at the cortical level. Subjects comprised 12 alcoholics with mild cognitive impairment [Mild group: Mini Mental State Examination Score (MMSE), ≥24; mean, 27.9 ± 1.6], 12 alcoholics with moderate to severe cognitive impairment (Moderate group: MMSE score, < 24; mean, 21.0 ± 2.5) and 12 normal subjects (Control group). SEP was recorded from the hand sensory area contralateral to the median nerve stimulated at the wrist. Single-pulse or paired-pulse stimuli at various interstimulus intervals (10–300 ms) were administered. Recovery functions of N9 (a peripheral nerve component), N20, N20-P25 and P25-N33 (cortical components) were studied. N20 recovery curves of both alcoholic groups were less suppressive than those of Controls, and P25-N33 recovery curves of the Moderate group were more excitatory than those of the Mild or Control groups. A disinhibited recovery pattern of N20 indicates subcortical dysfunction, and a disinhibited pattern of P25-N33 would be induced by cortical dysfunction. Therefore, subcortical dysfunction indicated by an abnormal N20 recovery pattern may contribute to the early cognitive impairment of alcoholics, whilst the cortical dysfunction indicated by an abnormal P25-N33 recovery pattern may contribute to the later cognitive impairment of alcoholics. 相似文献
60.