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101.
W. J. Spitzer 《Der Radiologe》1996,36(3):188-192
Summary
Two-dimensional conventional X-rays and computer tomographic imaging systems contribute to the diagnosis and surgical planning
of patients with orofacial malformations. The ability to reformat CT scans into three-dimensional osseous and soft tissue
surface images has a significant impact on the diagnosis and management of orofacial malformations. Cephalometric evaluation
with teleradiography provides precise insight into both the skeletal structures and the soft parts, enabling the radiologist
to assess the relationship among the different parts in a given subject, at any given time and in relation to the normal.
相似文献
102.
目的建立测定谷氨酸脱羧酶(GAD)抗体的方法,以探讨该抗体对胰岛素依赖型糖尿病(IDDM)的预测、早期诊断及其发病机制研究的意义。方法用专用酶反应试管建立放射性同位素底物测定GAD活性的分析方法。结果底物浓度为4mmol/ml(37kBq)时,酶活性测定在一定浓度范围内剂量效应呈直线关系(r=0989)。结合免疫沉淀与酶活性分析,建立了免疫沉淀酶活性分析测定GAD抗体的方法,2份IDDM患者GAD抗体阳性血清与酶活性免疫沉淀指数存在剂量效应关系。用免疫沉淀酶法测定15例正常人及20例病程1年以内的IDDM患者血清,两组酶活性免疫沉淀指数分别为0193±0087和0381±0121,差异有显著性(P<001)。按照超过正常人组免疫沉淀指数x+2s为阳性区分,20例IDDM患者血清中GAD抗体阳性9例,占45%。结论该方法简单,能直接反映酶活性的改变,无需高纯度的GAD,特别适用于刚开始从事GAD抗体研究的实验室及阳性血清筛查。 相似文献
103.
背景 育龄期女性胚胎着床失败及流产的最常见原因是胚胎异常,但移植经胚胎种植前遗传学检测(PGT)筛选后的正常胚胎后,仍出现种植失败或流产的原因目前并没有形成统一的结论。目的 分析PGT助孕后种植失败及流产的影响因素。方法 回顾性分析2018年12月至2021年2月在安徽医科大学第一附属医院生殖中心行PGT助孕的329例患者的临床资料,根据患者是否临床妊娠分为临床妊娠组(n=218)和种植失败组(n=111),并将临床妊娠组患者根据妊娠结局分为活产亚组(n=175)和流产亚组(n=43)。比较临床妊娠组和种植失败组,活产亚组和流产亚组的一般情况、促排卵及体外胚胎发育情况。采用多因素Logistic回归分析探讨PGT患者种植失败及流产的影响因素。绘制受试者工作特征(ROC)曲线分析多因素Logistic回归分析筛选出的影响因素对PGT患者发生种植失败及流产的预测价值。结果 多因素Logistic回归分析显示,既往流产次数≥2次〔OR=4.032 0,95%CI(2.423 0,6.710 0)〕、高密度脂蛋白胆固醇(HDL-C)水平低〔OR=3.890 0,95%CI(1.455 0,10... 相似文献
104.
Effects of epidural bupivacaine and epidural morphine on bowel function and pain after hysterectomy 总被引:2,自引:0,他引:2
T. THORÉN A. SUNDBERG M. WATTWIL J.–E. GARVILL U. JÜRGENSEN 《Acta anaesthesiologica Scandinavica》1989,33(2):181-185
A comparison was made of the effects of continuous epidural analgesia with bupivacaine and intermittent epidural morphine on bowel function after abdominal hysterectomy. The duration of postoperative ileus was assessed as the time from the end of operation to the first postoperative passage of flatus and feces. Twenty-two patients were randomly allocated to two equal groups. An "epidural morphine" group received general anesthesia and epidural morphine for postoperative pain relief, and an "epidural bupivacaine" group was given combined general anesthesia and epidural anesthesia with 0.5% bupivacaine intraoperatively and epidural analgesia with 0.25% bupivacaine postoperatively. Epidural morphine or bupivacaine was given for 42 h postoperatively. Pain intensity (visual analog scale) was low in both groups, but lower (P less than 0.05) in the epidural bupivacaine group. The time to first passage of flatus was 22 +/- 16 h in the epidural bupivacaine group and 56 +/- 22 h in the epidural morphine group (P less than 0.001). The time to first postoperative passage of feces was shorter (P less than 0.05) in the former than in the latter 57 +/- 44 h vs 92 +/- 22 h). The patients of the epidural bupivacaine group started intake of oral fluids earlier (P less than 0.01) and to a greater extent (P less than 0.05) than those in the epidural morphine group. It is concluded that the duration of postoperative ileus after hysterectomy is shorter when epidural bupivacaine is given for postoperative pain relief than when this is achieved by epidural morphine. 相似文献
105.
Human smooth pursuit during transient perturbations of predictable and unpredictable target movement
A. V. van den Berg 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1988,72(1):95-108
Summary The predictive component of human smooth pursuit was studied by perturbing sinusoidal target motion at unpredictable instants. The disturbances consisted of either a brief period of stabilization of the target on the fovea or a replacement of the sine by a ramp displacement for half a period. To minimize the effects of a possible change of the tracking strategy by the subject the transitions were masked and only the initial part of the response to the disturbance was analyzed. After stabilization on the fovea the eye oscillation continued at the frequency of the preceding target movement for about one half-cycle, whereupon the oscillation was rapidly damped. The mean unidirectional smooth eye acceleration was 70% of the mean unidirectional target acceleration prior to the stabilization. This suggests that during pursuit of a sinusoidal target movement about 75% of the oculomotor response is generated by predictive processes. When the sine was replaced by a ramp, starting at the velocity zero-crossing, the eye accelerated away from the target for ca. 180 ms irrespective of the frequency of prior tracking. In contrast, when the ramp started at the peak velocity of the sinusoidal target motion the eye accelerated away from the target for more than a quarter period. After foveal stabilization during pursuit of a pseudorandom stimulus, the eye continued to oscillate for less than one period at approximately the highest frequency present in the stimulus. The frequency characteristics of human smooth pursuit of predictable as well as unpredictable target motion were correctly simulated by a model, which derived its predictive properties from a lead element, tuned to the current frequency of the target motion. 相似文献
106.
107.
Objective To investigate the proliferation potential of colon cancer cells co-cultured with different proportions regenerating hepatocytes and role of the cell growth factors related to liver regeneration in vitro.Methods Active regenerating hepatocytes were obtained by collagenase perfusion in situ of rats models underwent 70% liver resection after 24 hours.Co-cultures with different proportions of hepatocytes to human colon cell line SW480 were performed respectively.The proportion of hepatocytes to human colon cell line SW480 Was 10:1 in group A,1:1 in group B.There was only human colon cell line SW480 in group C(control group).Proliferation capacity was assessed with the percentage by 3H-thy incorporation.Concentration of epidermal growth factor(EGF),insulin-like growth factor-1(IGF-1)and hepatocyte growth factor(HGF)was analyzed by ELISA.Results There was no significant difference among the 3 groups in 3H-thy incorporation percentage,and concentration of EGF,IGF-land HGF after 24 hours' culture(P>0.05).3H-thy incorporation percentage(15.9±1.4,13.2±1.5),and concerntration of EGF [(722.9±55.4)ng/L,(498.2+41.5)ng/L]and IGF-1[(755.2±35.7)ng/L,(538.1±37.5)ng/L]in Group A and B were higher than that in group C after 72 hours(P<0.05).Especially the indexes above in group A were higher than that in group B(P<0.05).there was no significant difference in concerntration of HGF among the 3 groups after 72 hours(P>O.05).Conclusions These results imply that the regenerating hepatocytes contribute to the hyperproliferative state of co-culturing colon cancer cells.The mechanism maybe have relationship with EGF and IGF-1 high expression in colon cancer cells caused by growth signals coming from hepatocytes. 相似文献
108.
Martina Adler Frank Rittig Stefan Becker Harald Pasch 《Macromolecular chemistry and physics.》2005,206(22):2269-2277
Summary: The chromatographic analysis of hydrophilic copolymers is complicated due to the fact that in most cases aqueous eluents must be used. In aqueous eluents different polar and ionic effects may disturb the selective interactions between the macromolecules and the stationary phase making it impossible to separate such copolymers with regard to chemical composition. Therefore, 2D chromatography combining a separation according to composition with a separation according to molar mass has been applied mostly to polymers that are soluble in organic solvents. The present contribution describes experimental approaches to analyze such hydrophilic copolymers by 2D‐chromatography. For a model polymer system resulting from the copolymerization of methacrylic acid and a poly(ethylene glycol) macromonomer, it is shown that different analytical techniques including SEC, LC‐CC, MALDI‐TOF MS and 2D chromatography can be used to analyze the different parameters of molecular heterogeneity of such copolymers.
109.
M. O. Toll 《Medical & biological engineering & computing》1984,22(1):2-5
The direct measurement of blood pressure has found widespread use in intensive care units, operating rooms, and in emergency
departments. Infection, air embolism and thrombosis are some of the risks to patients associated with both the cannulation
procedure and with the apparatus used in the blood-pressure measuring process. Although there is constant revision in an attempt
to reduce these risks, they cannot be completely eliminated. The need for direct blood-pressure measurements and the physiological
effects of air embolism and thrombosis are reviewed. Infection and problems related to the techniques used to insert the catheters
are not discussed. 相似文献
110.
P. R. Chadwick D. F. J. Brown M. H. Wilcox T. A. Collyns E. Walpole J. Dillon R. Smith G. Gopal Rao B. A. Oppenheim 《Clinical microbiology and infection》1997,3(5):559-563
Objective: To compare four vancomycin-containing agar media for the isolation of glycopeptide-resistant enterococci (GRE) from clinical fecal specimens: kanamycin-aesculin-azide (KAA) agar; bile-aesculin-polymixin (BAP) agar; aztreonam-amphotericin blood (CBAA) agar; and neomycin blood (CBN) agar.
Methods: Fecal specimens from 125 patients were inoculated onto each medium. Media were examined for enterococci after incubation for up to 48 h. Enterococci were identified to species level, and glycopeptide phenotypes were determined by measuring minimum inhibitory concentrations of vancomycin and teicoplanin.
Results: GRE were isolated from 44/125 samples. Enterococcus faecalis and Enterococcus faecium isolates, expressing glycopeptide resistance of the VanA or VanB phenotypes, were recovered from 27/33 (82%) specimens on BAP medium, 26/33 (79%) on KAA medium, and 21/33 (64%) on CBN and CBAA media. Enterococcus gallinarum and Enterococcus casseliflavus isolates expressing low-level glycopeptide resistance (VanC phenotype) were recovered from 14/15 (93%) specimens on CBAA medium, 7/15 (47%) on KAA and CBN media, and 6/15 (40%) on BAP medium.
Conclusions: The media tested in this study, with the exception of CBN medium, detected at least 75% of patients colonized by GRE. Further development of BAP, CBAA and KAA media is warranted to improve growth and selectivity. 相似文献
Methods: Fecal specimens from 125 patients were inoculated onto each medium. Media were examined for enterococci after incubation for up to 48 h. Enterococci were identified to species level, and glycopeptide phenotypes were determined by measuring minimum inhibitory concentrations of vancomycin and teicoplanin.
Results: GRE were isolated from 44/125 samples. Enterococcus faecalis and Enterococcus faecium isolates, expressing glycopeptide resistance of the VanA or VanB phenotypes, were recovered from 27/33 (82%) specimens on BAP medium, 26/33 (79%) on KAA medium, and 21/33 (64%) on CBN and CBAA media. Enterococcus gallinarum and Enterococcus casseliflavus isolates expressing low-level glycopeptide resistance (VanC phenotype) were recovered from 14/15 (93%) specimens on CBAA medium, 7/15 (47%) on KAA and CBN media, and 6/15 (40%) on BAP medium.
Conclusions: The media tested in this study, with the exception of CBN medium, detected at least 75% of patients colonized by GRE. Further development of BAP, CBAA and KAA media is warranted to improve growth and selectivity. 相似文献