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51.
目的:研究不同剂量的放射性125I粒子对家兔尿道的放射性损伤。方法:麻醉下将放射性125I粒子植入雄性家兔尿道旁1.0cm处。125I粒子的放射性粒子活度分别为14.8MBq(A组)、29.6MBq(B组)和44.4MBq(C组),对照组(D组)仅尿道旁种植相当于粒子大小无放射性的无菌铅管1粒。植入后4周,摄尿道片,观察粒子位置等情况;原手术切口切开,取放射粒子周围2.0cm范围内的家兔尿道组织作肉眼、光学显微镜和电子显微镜观察,进行放射性损伤的评价。结果:术后4周,肉眼及光学显微镜观察,实验组与对照组粒子周围的尿道粘膜、粘膜下及肌层所见基本一致;C组少部分电镜视野中观察到尿道上皮胞质出现较多空泡变性、空化、嵴稀疏等超微结构的损伤。光镜下尿道入射性损伤评分,A、B、C、D组分别为(2.20±0.18)、(2.23±0.15)、(2.27±0.10)、(2.10±0.17)分,A、B、C组与D组相比,差异无显著性(P>0.05)。对线粒体作FlaMeng半定量分析,A、B、C、D各组评分分别为(1.23±0.13)、(1.34±0.25)、(1.41±0.30)、(1.12±0.13)分,A、B、C各组与D组(对照组)相比,差异无显著性(P>0.05)。结论:放射性125I粒子对尿道放射性损伤随粒子的放射性活度的增加而逐渐加重,呈明显的放射性活度效应关系;正常剂量的放射性粒子对尿道的损伤是很轻微的,是安全可行的。 相似文献
52.
Richard A. Perugini Steven H. Quarfordt Stephen Baker Donald R. Czerniach Demetrius E. M. Litwin John J. Kelly 《Journal of gastrointestinal surgery》2007,11(9):1083-1090
Introduction Obese individuals may have normal insulin–glucose homeostasis, insulin resistance, or diabetes mellitus. Whereas gastric bypass
cures insulin resistance and diabetes mellitus, its effects on normal physiology have not been described. We studied insulin
resistance and β-cell function for patients undergoing gastric bypass.
Methods One hundred thirty-eight patients undergoing gastric bypass had fasting insulin and glucose levels drawn on days 0, 12, 40,
180, and 365. Thirty-one (22%) patients with diabetes mellitus were excluded from this analysis. Homeostatic model of assessment
was used to estimate insulin resistance, insulin sensitivity, and β-cell function. Based on this model, patients were categorized
as high insulin resistance if their insulin resistance was >2.3.
Results Body mass index did not correlate with insulin resistance. Forty-seven (34%) patients were categorized as high insulin resistance.
Correction of insulin resistance for this group occurred by 12 days postoperatively. Sixty (43%) patients were categorized
as low insulin resistance. They demonstrated an increase of β-cell function by 12 days postoperatively, which returned to
baseline by 6 months. At 1 year postoperatively, the low insulin resistance group had significantly higher β-cell function
per degree of insulin sensitivity.
Conclusions Adipose mass alone cannot explain insulin resistance. Severely obese individuals can be categorized by degree of insulin resistance,
and the effect of gastric bypass depends upon this preoperative physiology. 相似文献
53.
^125I放射微粒微创植入治疗前列腺癌 总被引:1,自引:0,他引:1
目的观察^125I放射微粒植入对前列腺癌的治疗效果。方法对26例临床确诊为前列腺癌患者经皮穿刺在癌组织植入^125I放射微粒,每例平均36粒,术后复查肛诊、B超、影像学及血生化指标。结果患者植入治疗经过顺利,2例少量出血,留置导尿后愈合,3个月后经肛诊、直肠B超示结节缩小,前列腺特异性抗原(PSA)降低,多普勒超声显示结节内动脉收缩期最大血流速度(VS)、阻力指数(RI)及动脉搏动指数(PI)均明显下降。结论^125I放射微粒植入对前列腺癌的治疗安全性好、效果可靠。 相似文献
54.
55.
L. Kalinauskiene D. Cekuoliene M. H. Van IJzendoorn † M. J. Bakermans-Kranenburg † F. Juffer† I. Kusakovskaja 《Child: care, health and development》2009,35(5):613-623
Objective This randomized control trial examined the effects of a short-term, interaction-focused and attachment-based video-feedback intervention (VIPP: video-feedback intervention to promote positive parenting).
Design VIPP effect on mothers' sensitive responsiveness and infant–mother attachment security was evaluated in a sample ( n = 54) of low sensitive, non-clinical, middle class Lithuanian mothers.
Methods Maternal sensitivity was assessed in a free play session with the Ainsworth's sensitivity scale, and attachment security was observed using the Attachment Q sort for home observations.
Results We found that the intervention mothers indeed significantly improved their sensitive responsiveness through participation in our VIPP. The effect size was large according to Cohen's criteria, d = 0.78. VIPP enhanced maternal sensitive responsiveness even when maternal age, educational level, depression, daily hassles, efficacy, infant gender, and infant negative and positive affect were controlled for. However, attachment security in the VIPP infants was not enhanced after the intervention, compared with the control infants, and the infants did not seem to be differentially susceptible to the increase in maternal sensitivity dependent on their temperamental reactivity.
Conclusion We suggest that a relatively brief and low-cost programme can provide effective support for mothers who lack sensitivity in the interactions with their infants. 相似文献
Design VIPP effect on mothers' sensitive responsiveness and infant–mother attachment security was evaluated in a sample ( n = 54) of low sensitive, non-clinical, middle class Lithuanian mothers.
Methods Maternal sensitivity was assessed in a free play session with the Ainsworth's sensitivity scale, and attachment security was observed using the Attachment Q sort for home observations.
Results We found that the intervention mothers indeed significantly improved their sensitive responsiveness through participation in our VIPP. The effect size was large according to Cohen's criteria, d = 0.78. VIPP enhanced maternal sensitive responsiveness even when maternal age, educational level, depression, daily hassles, efficacy, infant gender, and infant negative and positive affect were controlled for. However, attachment security in the VIPP infants was not enhanced after the intervention, compared with the control infants, and the infants did not seem to be differentially susceptible to the increase in maternal sensitivity dependent on their temperamental reactivity.
Conclusion We suggest that a relatively brief and low-cost programme can provide effective support for mothers who lack sensitivity in the interactions with their infants. 相似文献
56.
Werner Spileers Guy A. Orban Hugo Maes Luc Missotten 《Documenta ophthalmologica. Advances in ophthalmology》1988,68(3-4):363-374
CMSS-VEPs are presented as a sensitive, non-invasive functional investigation technique of the visual function, applicable in clinical practice. New improvements of the technique are presented. The underlying neuronal mechanisms are discussed. The clinical use is illustrated in a case of optic neuritis. 相似文献
57.
R. M. Kappel R. Dijkstra J. B. Storm van Leeuwen P. Houpt M. Kuyper 《European journal of plastic surgery》1997,20(2):60-65
Two methods of breast reduction were performed between 1981 and 1986. One was wedge resection of the breast in which nipple and gland were disconnected. The other was the tangential and circumferential breast reduction, in which the nipple remained in continuity with the gland. For each method, there were 21 patients. The mean follow-up was 5 years and 9 months. In both groups, 8 patients had 11 children, but only the tangential reduction patients lactated. They also had better subjective nipple sensitivity whereas objectively the differences were rather small. 相似文献
58.
Christopher W. Theodorakis B. G. Blaylock Lee R. Shugart 《Ecotoxicology (London, England)》1997,6(4):205-218
Female mosquitofish (Gambusia affinis) were collected from two sites located on the US Department of Energy's Oak Ridge Reservation that are contaminated with 137Cs, 90Sr, other radionuclides and chemical genotoxicants. Fish from non- radionuclide contaminated environments located off the reservation were also collected. DNA, extracted from liver tissue and blood cells, was examined by gel electrophoresis for structural damage in the form of strand breakage. In general, the level of DNA strand breaks was elevated in fish from radionuclide-contaminated sites with observed differences in the number and type of strand breaks between liver tissue and blood cells. The number of malformed embryos was higher in fish at the contaminated sites, and varied with season. Fecundity was negatively correlated with the level of double strand breaks in the DNA of fish from one contaminated site. Females with broods that included malformed embryos had more DNA strand breakage than those that did not; and furthermore, a threshold effect was observed between the occurrence of malformed embryos and the presence of double strand breaks in the DNA of the mother. These findings have implications for both ecological risk assessment and evolutionary ecology 相似文献
59.
Wolfgang H Oertel Tobias W?chter Niall P Quinn Gudrun Ulm Dirk Brandst?dter 《Movement disorders》2003,18(4):430-432
According to the consensus statement on the diagnosis of multiple system atrophy (MSA), erectile dysfunction is required for male patients to fulfil the urinary incontinence criterion. However, there is no equivalent item for female patients. We questioned 19 female patients with MSA of the parkinsonian type (MSA-P), 28 female patients with Parkinson's disease (PD), and 27 healthy controls on their genital sensitivity. A total of 47% of the MSA patients but only 4% of the PD patients and 4% of the control group admitted to reduced genital sensitivity, a highly significant difference (P < 0.001). Moreover, the appearance of reduced genital sensitivity in female MSA patients showed a close temporal relation to the onset of the disease. If these preliminary results can be confirmed and further specified in a larger sample, a historical item of reduced genital sensitivity in female patients might become a diagnostic feature for MSA, comparable to erectile dysfunction in male patients. 相似文献
60.
脉冲式电磁辐射对大鼠血脑屏障影响的量效关系 总被引:6,自引:1,他引:5
目的 研究脉冲式电磁辐射(EMR)对大鼠血脑屏障(BBB)影响的量效关系。方法 采用伊思蓝静脉注射,荧光显微镜下观察不同脉冲次数的EMR辐照对大鼠BBB开放的影响。结果 伊思蓝在EMR诱发的大鼠BBB开放局部呈现荧光斑;随着EMR脉冲次数(0~200次)的增加,荧光斑数量增加、面积增大;荧光斑在EMR组全脑的分布,以皮质、丘脑、下丘脑、小脑、尾壳核和延髓较多。结论 不同脉冲次数EMR诱发大鼠BBB开放程度不同,随脉冲次数增加,血管通透性增强,200次时达开放高峰,皮质区BBB开放最明显。 相似文献