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1.
The accompanying paper examines the subject of NMR phantoms. The paper reports on initial experience with existing phantoms and reviews proposals from various standards groups and professional organizations. Many image tests are illustrated by existing vendor phantoms. The paper concludes that many phantoms already meet or exceed most of the suggestions for tests of classical imaging parameters, which can be pursued by first order adaptations of CT phantoms. The paper does, however, point out the limitations of existing phantoms and raise the possibility of developing phantoms that more accurately reflect human shapes and cavities, and which present more realistic resistive losses, and T1 and T2 values.  相似文献   
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The objective was to demonstrate bioequivalence between s.c. and i.m. administration of Humegon (FSH/LH ratio 1:1) and Normegon (FSH/LH ratio 3:1). In two randomized, single-centre, cross-over studies, 18 healthy volunteers on each formulation were assigned to one of the two administration sequences. Subjects were given single doses of one of the above gonadotrophins after endogenous gonadotrophin production had first been suppressed using high-dose oral contraceptive. Subsequently, rate (Cmax, tmax) and extent (AUC) of absorption of follicle stimulating hormone (FSH) and luteinizing hormone (LH) were determined for 14 days. For Cmax and AUC, analysis of variance (ANOVA) was performed on log-transformed data and for tmax ANOVA was performed on ranks. Intramuscular and s.c. injections of Humegon were bioequivalent with respect to the main pharmacokinetic parameters, being AUC and Cmax of FSH absorption. Intramuscular and s.c. injections of Normegon were bioequivalent with respect to the AUC of FSH and not bioequivalent with respect to the Cmax of FSH. For tmax of FSH as well as for most LH variables of both preparations, bioequivalence could not be proven due to the high intra- and interindividual variability and/or concentrations being close to the detection limit. Thus, the main pharmacokinetic FSH variables after i.m. and s.c. administration of Humegon and Normegon were bioequivalent.   相似文献   
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传染性肺结核患者家庭中儿童结核感染发病及预防的研究   总被引:3,自引:1,他引:3  
目的 分析传染性肺结核患者家庭中的儿童结核感染和发病情况 ,探讨预防儿童发病的有效方案。方法 对与传染性肺结核患者密切接触的儿童进行X线胸透和做结核菌素试验 ;对结核菌素强阳性者给予预防性治疗。结果 与传染性肺结核患者密切接触的儿童感染率为 88 2 %。规则预防治疗组、不规则预防治疗组和不接受预防治疗组的患病率分别为 :8 3%、4 7 6 %、5 8 8%。结论 与传染性肺结核患者密切接触的儿童属于高危人群 ,给予预防性治疗可减少发病。  相似文献   
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Heteromeric connexons in lens gap junction channels.   总被引:11,自引:0,他引:11       下载免费PDF全文
Gap junction channels are formed by paired oligomeric membrane hemichannels called connexons, which are composed of proteins of the connexin family. Experiments with transfected cell lines and paired Xenopus oocytes have demonstrated that heterotypic intercellular channels which are formed by two connexons, each composed of a different connexin, can selectively occur. Studies by Stauffer [Stauffer, K. A. (1995) J. Biol. Chem. 270, 6768-6772] have shown that recombinant Cx26 and Cx32 coinfected into insect cells may form heteromeric connexons. By solubilizing and subfractionating individual connexons from ovine lenses, we show by immunoprecipitation that connexons can contain two different connexins forming heteromeric assemblies in vivo.  相似文献   
7.
目的 分析延边地区建立肺结核归口转诊模式对肺结核病人的转诊到位率的影响,探讨提高转诊到位率的方法。方法 对全州8个县(市)医院、中医医院、中心卫生院、大型厂矿企事业单位职工医院的执法检查考核资料进行评价。结果 1.建立归口转诊模式前期转诊率为48.3%,转诊到位率为29.0%,后期转诊率为89.0%,转诊到位率为72.4%,有明显提高;2.前期年平均涂阳病人新登记率为13.36/10万,后期为17.86/10万,实施归口转诊模式前期与实施后期的指标有显著性差异(P<0.01)。结论 延边地区实施的肺结核病人归口转诊模式,对提高肺结核病的转诊到位率十分有效,应不断完善并深入推广。  相似文献   
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There is much debate relating to possible abnormalities in respiratory control mechanisms in infants considered at increased risk for sudden infant death syndrome (SIDS). The P0.1 occlusion technique was used to assess the central respiratory response to hyperoxic hypercapnia during quiet sleep in 21 normal infants, 13 siblings of SIDS victims, and 17 infants with apparent life threatening events. The slope of P0.1 plotted against carbon dioxide concentration increased exponentially with age, independent of body weight in each group. Birth weight has a significant effect on slope with a lower weight predisposing to a lower slope. Siblings as a group had a significantly lower slope at any given age than normal infants, whereas the infants who had had apparent life threatening events were not significantly different from the controls. As intragroup variation in both siblings and control groups greatly exceeded the significant intergroup differences observed, the technique cannot identify individual infants as belonging to one or other group.  相似文献   
10.
目的 探讨复治肺结核病人形成原因。方法 使用调查表的方法 ,对前来诊治的复治涂阳肺结核病人的首次诊疗 ,管理情况进行问卷调查。结果 综合医院仍然为大多数患者的首次诊疗单位 ,因此部分肺结核患者未能得到正确的诊断、治疗和化疗管理。导致 67.2 %病人“中断”或“间断”治疗 ;另外结核病健康教育宣传做得不够 ,60 .3 %的患者诊断前未接受过防痨宣教 ,3 4.5 %的患者接受初次化疗时仍未得到宣教。这些均在导致复治病人的产生中起了重要作用。结论 加大DOTS覆盖面 ,加强归口管理力度 ,做好防治结核病教育工作是防止复治肺结核病人产生的重要环节。  相似文献   
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