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991.
992.
Vascular endothelial growth factor is produced by peritoneal fluid macrophages in endometriosis and is regulated by ovarian steroids. 总被引:20,自引:0,他引:20 下载免费PDF全文
J McLaren A Prentice D S Charnock-Jones S A Millican K H Müller A M Sharkey S K Smith 《The Journal of clinical investigation》1996,98(2):482-489
Angiogenesis is important in the pathophysiology of endometriosis, a condition characterized by implantation of ectopic endometrium in the peritoneal cavity. Vascular endothelial growth factor (VEGF) is a potent angiogenic factor involved in physiological and pathological angiogenesis, and elevated levels of VEGF are found in peritoneal fluid of patients with endometriosis. Our aim was to investigate the site of expression and regulation of VEGF in endometriosis. VEGF immunoreactivity was found in tissue macrophages present in ectopic endometrium and in activated peritoneal fluid macrophages. Macrophage activation was highest in women with endometriosis, and media conditioned by peritoneal fluid macrophages from these women caused a VEGF-dependent increase in endothelial cell proliferation above that seen from normal women. Peritoneal fluid macrophages secreted VEGF in response to ovarian steroids, and this secretion was enhanced after activation with lipopolysaccharide. Peritoneal fluid macrophages expressed receptors for steroid hormones. VEGF receptors flt and KDR (kinase domain receptor) were also detected, suggesting autocrine regulation. During the menstrual cycle, expression of flt was constant but that of KDR was increased in the luteal phase, at which time the cells migrated in response to VEGF. KDR expression and the migratory response were significantly higher in patients with endometriosis. This study demonstrates that activated macrophages are a major source of VEGF in endometriosis and that this expression is regulated directly by ovarian steroids. 相似文献
993.
Alan Grieve Shona McLaren William R. Lindsay 《British Journal of Learning Disabilities》2007,35(1):30-37
To review the literature on issues surrounding the sexuality of people with moderate to severe learning disability (SLD), and evaluate available assessment and training methods. This research arose from an increasing number of referrals for clinical intervention in the training and education of appropriate social and sexual behaviour in people with moderate to SLD. What became apparent was the lack of suitable materials and assessments, which is significant as a large number of persons with SLD have problems with language, and so require tools and programmes which have enhanced levels of pictorial support. This research was necessary as people with SLD are vulnerable and have been open to emotional and sexual abuse [Ment Handicap Res 16 (1993) 193]. Also, the present study was also required to help keep clients safe and reduce their vulnerability. It has been proposed that this should be achieved through providing educative input. An extensive review of the literature revealed that the research on sexuality in SLD was limited. Furthermore, where research had been conducted, poor methodology or validation issues were common, and materials appeared overly complicated for clients with moderate to SLD. Further research into the development and validation of assessment tools and training programmes which increase appropriate sexual behaviours is urgently required. 相似文献
994.
Objective measurement of backscattered light from the anterior and posterior cornea in vivo 总被引:1,自引:0,他引:1
Patel SV Winter EJ McLaren JW Bourne WM 《Investigative ophthalmology & visual science》2007,48(1):166-172
PURPOSE: To develop an objective and repeatable method of measuring corneal backscattered light from different depths of the cornea in vivo. METHODS: A modified slit lamp ("scatterometer"), with a video camera and synchronous white strobe light, was used to capture images of a 0.1-mm-wide slit beam through the cornea. Image analysis software was developed to measure backscatter from digitized high-magnification images of 82 normal corneas of 41 subjects. Forty eyes of 20 of the same subjects were examined again after 1 month. Mean backscatter from the anterior, middle, and posterior thirds of the cornea was compared between repeated measurements, and expressed in arbitrary scatter units (SU). RESULTS: Backscatter in the anterior third of the cornea was 451 +/- 42 SU (mean +/- SD, n = 82), from the middle third was 274 +/- 29 SU (n = 82), and from the posterior third was 242 +/- 28 SU (n = 82). The difference in backscatter measured a month apart was 5 +/- 27 SU (P = 0.34), 2 +/- 17 SU (P = 0.42), and 0 +/- 15 SU (P = 0.95) in the anterior, middle, and posterior thirds of the cornea, respectively. Minimum detectable differences between measurements were 12, 8, and 7 SU in the anterior, middle and posterior thirds, respectively (alpha = 0.05, beta = 0.20, n = 40). CONCLUSIONS: Backscatter can be measured at different depths of the cornea from high-magnification digitized images of a narrow slit beam through the cornea. The method is objective and repeatable and can be applied in prospective studies of deep and posterior lamellar keratoplasty. 相似文献
995.
Meyskens FL McLaren CE Pelot D Fujikawa-Brooks S Carpenter PM Hawk E Kelloff G Lawson MJ Kidao J McCracken J Albers CG Ahnen DJ Turgeon DK Goldschmid S Lance P Hagedorn CH Gillen DL Gerner EW 《Cancer prevention research (Philadelphia, Pa.)》2008,1(1):32-38
Preclinical studies of chemoprevention drugs given in combination at low doses show remarkable efficacy in preventing adenomas with little additional toxicities, suggesting a strategy to improve risk to benefit ratios for preventing recurrent adenomas. Three hundred seventy-five patients with history of resected (> or =3 mm) adenomas were randomly assigned to receive oral difluoromethylornithine (DFMO) 500 mg and sulindac 150 mg once daily or matched placebos for 36 months, stratified by use of low-dose aspirin (81 mg) at baseline and clinical site. Follow-up colonoscopy was done 3 years after randomization or off-study. Colorectal adenoma recurrence was compared among the groups with log-binomial regression. Comparing the outcome in patients receiving placebos to those receiving active intervention, (a) the recurrence of one or more adenomas was 41.1% and 12.3% (risk ratio, 0.30; 95% confidence interval, 0.18-0.49; P < 0.001); (b) 8.5% had one or more advanced adenomas, compared with 0.7% of patients (risk ratio, 0.085; 95% confidence interval, 0.011-0.65; P < 0.001); and (c) 17 (13.2%) patients had multiple adenomas (>1) at the final colonoscopy, compared with 1 (0.7%; risk ratio, 0.055; 0.0074-0.41; P < 0.001). Serious adverse events (grade > or =3) occurred in 8.2% of patients in the placebo group, compared with 11% in the active intervention group (P = 0.35). There was no significant difference in the proportion of patients reporting hearing changes from baseline. Recurrent adenomatous polyps can be markedly reduced by a combination of low oral doses of DFMO and sulindac and with few side effects. 相似文献
996.
Cytokeratin 19 and galectin-3 immunohistochemistry in the differential diagnosis of solitary thyroid nodules 总被引:21,自引:0,他引:21
AIMS: The immunohistochemical expression of cytokeratin 19 (CK 19) and galectin-3 was evaluated in 69 thyroid lesions to assess their potential as markers in the diagnosis and classification of thyroid malignancy. The following were studied: 26 cases of papillary carcinoma, 12 of follicular carcinoma, 20 follicular adenomas, two medullary carcinomas, one anaplastic carcinoma and eight multinodular goitres. METHODS AND RESULTS: Formalin-fixed paraffin-embedded thyroid tissues were stained immunohistochemically for both CK 19 and galectin-3. CK 19 expression was found in all 26 papillary carcinomas, five of 12 follicular carcinomas, two of two medullary carcinomas and one case of anaplastic carcinoma. Only five of 20 follicular adenomas were positive for CK 19, and this was in a focal distribution. Two of eight multinodular goitres stained focally positive. Galectin-3 expression was found in 22 of 26 papillary carcinomas, 12 of 12 follicular carcinomas and one of two cases of medullary carcinoma. Only two of 20 follicular adenomas were positive. Three of eight multinodular goitres showed focal galectin-3 expression. CONCLUSIONS: Our findings suggest that the immunohistochemical localization of CK 19 and of galectin-3 is a useful adjunct to the histopathological diagnosis of a solitary thyroid lesion. The expression of CK 19 favours a diagnosis of papillary carcinoma in all its variant patterns. Galectin-3 may serve as a marker for the recognition of follicular carcinoma, particularly the minimally invasive form. 相似文献
997.
PurposePhenylephrine has been shown to affect intraocular pressure (IOP) but the mechanism of action is poorly understood. However, its action as a vasoconstrictor suggests possible effects on episcleral venous pressure (EVP). In this study, we evaluated the effect of phenylephrine on EVP and IOP in healthy subjects.MethodsForty eyes of 20 subjects were included. Each subject received 3 drops of phenylephrine 2.5% in one eye at 1-minute intervals. The fellow eye served as control. Blood pressure, heart rate, and IOP and EVP of both eyes were measured at baseline, 15 minutes, and 60 minutes after instillation of phenylephrine. IOP was measured by pneumatonometry. EVP was assessed by using a computer-controlled episcleral venomanometer. Changes in IOP, EVP, blood pressure, and heart rate at 15 and 60 minutes were analyzed by paired t-tests.ResultsIOP increased 15 minutes after instillation of phenylephrine in both treated (P = 0.001) and control eyes (P = 0.01) and returned to baseline at 60 minutes. The change in IOP at 15 minutes was not significantly different between the 2 groups. EVP in treated eyes was unchanged at 15 minutes (P = 0.8) but decreased significantly at 60 minutes (P < 0.001). In control eyes, there was no change in EVP at any time (P > 0.6). There were no significant changes from baseline in systolic and diastolic blood pressure and heart rate after instillation of phenylephrine.ConclusionsIOP elevation associated with topical phenylephrine is not caused by an increase in EVP in healthy subjects. Instead, EVP decreases with phenylephrine, but the mechanism remains to be determined. 相似文献
998.
999.
1000.
目的:探讨在慢性不可预知性应激(chronic unpredictable stress,CUS)模型中压力耐受大鼠海马结构CA3及海马齿状回(dentate gyrus,DG)内树突棘数量的改变情况,以期深入了解抑郁症发病的结构基础。方法:选用4~5周龄雄性sprague-dawley(SD)大鼠,将糖水偏好稳定的大鼠随机分为空白对照组和CUS造模组,造模组采取孤养并给予4周的CUS干预。根据糖水偏好结果筛选出CUS敏感组和CUS耐受组。利用免疫组织化学结合体视学方法对每组抽选出的5只大鼠海马结构CA3和DG内的树突棘数量进行精确的三维定量研究。结果:与空白对照组、CUS耐受组相比,CUS敏感组的糖水偏好百分比均明显下降(P=0.000,P=0.000),而空白对照组与CUS耐受组的糖水偏好百分比无明显差异(P=0.262);与空白对照组和CUS耐受组相比较,CUS敏感组大鼠海马结构CA3区内的树突棘数量明显下降(P=0.008,P=0.004),CUS敏感组大鼠海马结构DG区内的树突棘数量也明显下降(P=0.001,P=0.001);而在大鼠海马结构CA3及DG内,CUS耐受组与空白对照组的树突棘总数目无明显差异(P=0.656,P=0.950)。结论:CUS耐受组大鼠海马结构CA3及DG内树突棘的数量不受CUS干预的影响,提示海马结构内树突棘数量可能是抑郁症易感性差异的关键因素之一,为抑郁症的治疗提供了新的方向。 相似文献