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131.
J Naga Raju Guntupalli Sarita Padala A V Ramana Murty Gummuluri Ravi Kumar Muktineni Seetharami Reddy Byreddy Lakshminarayana Sreerama Prema Chand Kedarisetti Durga Prasad Angalakuduru Bhuloka Reddy Satti Vijayan Venkatathri V B Rama Lakshmi Pullela Satyanarayana Gavarasana 《European journal of cancer prevention》2007,16(2):108-115
Trace elemental analysis was carried out in the tissue samples of normal, benign hypertrophic and carcinoma prostate using the particle-induced X-ray emission technique. A proton beam of 3 MeV energy was used to excite the samples. The elements Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Se, and Br were identified and their concentrations were estimated. It is observed that in benign tissues the concentrations of Cl, K, Zn, and Se are lower (P<0.05) and those of Cr, Fe, Ni, and Cu are higher (P<0.05 ) than in normal tissues. The concentrations of K, Ca, Zn, Se, and Br are lower (P<0.01) and those of Ti, Cr, Mn, Fe, Ni, and Cu are significantly higher (P<0.0005) in cancerous tissues than in normal tissues. Free radicals generated by elevated levels of Cr, Fe, Ni, and Cu possibly initiate and promote prostate cancer by oxidative DNA damage. The excess Cu levels in cancerous tissues support the fact that Cu promotes cancer through angiogenesis. The higher levels of Fe observed in cancerous tissues might be a consequence of tumor growth through angiogenesis. Significantly higher levels of Ni and Cr observed in carcinoma tissues support the well-established role of Ni and Cr as carcinogens. It is likely that the observed low levels of Zn and Se in cancerous tissues lead to the development of prostate cancer owing to a decrease in antioxidative defense capacity and impaired immune function of cells and also suggest that the inability to retain high levels of Zn and Se may possibly be an important factor in the development and progression of malignant prostate cells. In order to substantiate the observed elevated or deficient levels of trace elements in initiating, promoting, and inhibiting prostate cancer, several cellular and molecular studies are required. 相似文献
132.
Sathyamangalam Ve Ramesh Ronnie George Premal M Soni Lakshmanan Palaniappan Prema Raju Pradeep G Paul Sivarathinasami Ramsathish Lingam Vijaya 《Optometry and vision science》2007,84(6):496-504
PURPOSE: To compare the effect of uncorrected refractive error on threshold estimation using frequency doubling perimetry (FDP) full-threshold N-30 with emmetropia among normal subjects. METHODS: One thousand two hundred ninety-nine subjects were enrolled from the Chennai Glaucoma Study, a population-based glaucoma prevalence study. Subjects underwent a comprehensive eye examination including the FDP full-threshold N-30 test. Normal subjects (with spherical equivalent refractive errors within +/-7 D) with no other ocular pathology were stratified into six groups based on the degree of myopia and hyperopia and compared with age-matched emmetropic controls. A subset of 22 subjects with higher refractive errors was assessed for within-subject effect on FDP parameters. The following FDP parameters were compared: mean deviation, pattern standard deviation, central threshold (CT), mean sensitivity (MS), paracentral points (PA), and peripheral threshold. RESULTS: The one-way analysis of variance between all refractive error groups and emmetropes showed no statistically significant difference for the mean deviation (p = 0.1002) and pattern standard deviation (p = 0.4789). FDP parameters did not show a statistically significant difference for between and within-group comparisons. The variability of FDP sensitivity (derived from the 95% confidence interval range) as a proportion of the threshold range of the instrument was 31, 41, 46, and 41% for CT, MS, PA, and peripheral sensitivity, respectively, without spectacle correction and 29, 34, 36, and 35% for CT, MS, PA, and peripheral sensitivity, respectively, with correction. The mean CT, PA, and peripheral sensitivity show a decreasing trend from central to periphery in all the refractive error groups and a similar trend was noted in the emmetropic controls. CONCLUSION: Between-subject (uncorrected ammetropes and age-matched emmetropes) and within-subject comparisons showed no statistically significant differences in any of the FDP parameters or in the contrast sensitivity estimates between the central and peripheral test locations. This finding is likely due to the high within-subject variability of FDP. 相似文献
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135.
Rao KL Goyal A Menon P Thapa BR Narasimhan KL Chowdhary SK Samujh R Mahajan JK 《Pediatric surgery international》2004,20(9):679-684
This paper presents a comparative prospective study of three modalities of surgical treatment for extrahepatic portal hypertension in children: central splenorenal shunt after splenectomy (CSS), side-to-side lienorenal shunt (SSLR) without splenectomy, and splenectomy and gastroesophageal devascularization (SGD). In an 18-month period, 27 procedures were performed: 10 CSS, 10 SSLR, and seven SGD. The outcomes were evaluated by fall in portal pressures, hematological parameters, shunt patency, splenic regression, and disappearance of esophageal varices. All three procedures were comparable in the fall of portal pressure after surgery. The average blood loss and operating time were statistically significant in favor of SSLR compared with CSS. At 3-month follow-up, shunt patency was confirmed by duplex Doppler study in all the patients in the SSLR group and in nine out of 10 patients in the CSS group. In the CSS and SGD groups, hypersplenism resolved in all the patients. In the SSLR group, blood counts improved in only five out of eight affected children. No patient re-bled during a follow-up of 3–5 years. There were no cases of hepatic encephalopathy or overwhelming postsplenectomy sepsis. In conclusion, CSS is useful when there is a large spleen, severe hypersplenism, and a shuntable splenic vein. SSLR is suitable when there is only mild splenomegaly, mild hypersplenism, and a shuntable splenic vein. Splenectomy and devascularization is the choice when there is no shuntable splenic vein. 相似文献
136.
Thirty children (45 units) in the age group 1 day-12 yrs with primary vesicoureteral reflux were studied prospectively and periodically assessed for renal function, scarring, grade of reflux and somatic growth parameters. Four children (6 units) with grade IV reflux underwent ureteric reimplantation. Complete resolution with medical management was seen in all 12 units of grade I-III reflux and in 5 of the remaining 27 units of grade IV-V reflux over 6 months-6 yrs. This group showed highly significant improvement in height . The weight gain of the above 2 groups was statistically significant compared to those with persistent reflux. Focal defects were seen initially in 62 percent refluxing units. None of the patients showed deterioration in renal function or formation of new scars over the next 1-7 years. Three children on conservative management showed persistent growth retardation with associated breakthrough infection, hypertension, multiple renal scars and poor renal functional volume. 相似文献
137.
Guillem JG Rapaport BS Kirchhoff T Kolachana P Nafa K Glogowski E Finch R Huang H Foulkes WD Markowitz A Ellis NA Offit K 《Journal of the American College of Surgeons》2003,196(2):222-225
BACKGROUND: Hereditary predisposition to colorectal cancer most often manifests itself as familial adenomatous polyposis from mutations of APC, or hereditary nonpolyposis colorectal cancer, resulting from mutations of MSH2, MLH1, MSH6, or other genes. Previously, we described a rare founder mutation MSH2*1906C > G in Ashkenazi Jews that was found in 8 of 1,345 individuals (0.6%) of Ashkenazi descent with colorectal cancer. This study seeks to characterize the proportion of individuals of Ashkenazi heritage with very early-onset colon cancer (diagnosed at age 40 or younger) that could be attributed to MSH2*1906C>G. STUDY DESIGN: We analyzed the carrier frequency of MSH2*1906C>G in paraffin samples from 31 Jewish patients age 40 or less, diagnosed with colorectal cancer at Memorial Sloan-Kettering and lymphocyte-derived DNA from 10 patients. We did not select for family history. Genotyping for MSH2*1906C>G was performed by polymerase chain reaction and restriction enzyme digestion methods. RESULTS: We detected the MSH2*1906G>C mutation in 3 of the 41 samples (7.14%) of patients who had colorectal cancer diagnosed at age 40 or younger. This incidence is significantly greater than the 8 in 1,345 (0.6%) we observed for cases of colorectal cancer in Ashkenazi Jews not selected for age (p = 0.004). CONCLUSION: Although very rare in the population, MSH2*1906G>C is found at an increased frequency in young Jewish patients with colorectal cancer. These results suggest that testing for the MSH2*1906G>C mutation should be included in the evaluation of Ashkenazi Jewish individuals diagnosed with early-onset colon cancer. 相似文献
138.
Padmanabhan P Rao SK Jayasree R Chowdhry M Roy J 《Journal of refractive surgery (Thorofare, N.J. : 1995)》2006,22(2):172-177
PURPOSE: To study the wavefront aberration profile of eyes with three different types of intraocular lenses (IOLs)--the Tecnis Z9000 (modified prolate surface design) (Pfizer, New York, NY), the Acrysof MA60BM (unequal biconvex optic) (Alcon, Ft Worth, Tex), and the Sensar Optiedge AR40e (equibiconvex optic) (AMO, Santa Ana, Calif)--in eyes following cataract surgery. METHODS: This study was conducted in two parts. The first part was a randomized open study of 32 eyes of 16 patients who underwent bilateral phacoemulsification with a foldable IOL in the capsular bag. A Tecnis Z9000 IOL was implanted in one eye and an Acrysof MA60BM IOL in the fellow eye. The ALLEGRETTO WAVE Analyzer (Wavelight Laser Technologies AG, Erlangen, Germany) was used to measure ocular aberrations 2 weeks after surgery. A paired t test was used to compare each Zernike term from Z3(-3) to Z6(6) between fellow eyes (pupil diameter = 6 mm). In the second part of the study, the wavefront aberrations of 16 eyes that underwent an identical surgical procedure as in the first part of the study but had a Sensar Optiedge AR40e IOL implanted were studied and compared with eyes with the Tecnis Z9000 and Acrysof MA60BM IOLs. RESULTS: The mean spherical aberration (Z4(0)) was statistically significantly lower in eyes with a Tecnis Z9000 IOL (Z4(0) = 0.07 +/- 0.12 microm) compared with eyes with an Acrysof MA60BM IOL (Z4(0) = 0.29 +/- 0.20 microm, P < .001) and with eyes with a Sensar Optiedge AR40e IOL (Z4(0) = 0.20 +/- 0.09 microm, P = .002). No statistically significant differences were noted in any of the Zernike terms between eyes with Acrysof MA60BM and Sensar Optiedge AR40e IOLs, or in the root-mean-square (RMS) of total higher order aberrations among the three IOL groups. CONCLUSIONS: The implantation of a Tecnis Z9000 IOL produces a significant reduction in spherical aberration of the eye. No significant differences were noted in the wavefront profile between eyes with Acrysof MA60BM and Sensar Optiedge AR40e IOLs. No significant differences were found in the RMS of total higher order aberrations among the three IOL groups. 相似文献
139.
Pharmacokinetics of norethindrone (NET) was evaluated in eleven women belonging to a low socio-economic group and in five womem belonging to the high socio-economic group after the administration of an oral dose of 0.35 mg NET minipill on an empty stomach. Blood samples were collected at different intervals of time over a period of 24 hours. Plasma NET was estimated by radioimmunoassay. In all women, peak levels of NET occurred within 1-2 hours and a semi-log plot of plasma NET levels showed a biexponential decline. The half-life of plasma NET clearance was relatively shorter in women of low socio-economic group with poor nutritional status as indicated by anthropometric indices, as compared to that in well nourished women of high socio-economic group. There was a significant positive correlation between weight/(height) 2x 100 index on the one hand and t1/2 (beta) on the other in all the women studied, thereby suggesting a role for nutritional status in the metabolic handling of NET. 相似文献
140.
M. Madhavan Prema Sivasankaran C. Ratnakar K. Chandra 《Indian journal of pediatrics》1972,39(3):65-67
Summary In a series of 260 perinatal autopsies, 30% showed epithelial squames in fetal alveoli. No correlation could be obtained to
implicate the presence of alveolar squames as a pathogenic lesion in respiratory insufficiency of the new born.
From the Department of Pathology, JIPMER, Pondicherry 6. 相似文献