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51.
High-performance thin-layer chromatography (HPTLC) was used to determine neutral lipids and phospholipids in the intestinal trematode Echinostomacaproni from experimentally infected ICR mice fed a high-fat diet (hen's egg yolk) as compared with worms from mice fed a standard laboratory diet. Worms were removed from the hosts at 2, 3, and 4 weeks postinfection (p.i.). Analysis by TLC-densitometry showed significantly greater amounts of triacylglycerols and free sterols at 2, 3, and 4 weeks p.i. in worms from mice on the high-fat diet as compared with worms from mice on the standard laboratory diet. Significantly greater amounts of phosphatidylcholine and phosphatidylethanolamine were found in worms from mice on the high-fat diet as compared with worms from those on the standard diet at 2 weeks p.i. but not at 3 and 4 weeks p.i. The results of this study suggest that the host diet influences the lipid content of E. caproni adults. 相似文献
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Imaging is central to anatomic pathology. The captured images are used for documentation, archiving, teaching, and publication. The advent of low-cost, consumer-type, high-end digital cameras has provided a convenient, easy-to-use alternative for routine image acquisition. The various applications for digital image acquisition in anatomic pathology include, among others, digitizing conventional photographs, digital gross photography and digital macrophotography, digitizing radiographic images, and digital photomicrography. This article reviews digital image acquisition in the anatomic pathology setting using a consumer-type digital camera. The camera type chosen as an example for the discussion was selected for its popularity and wide use among pathologists and for its potential to function as a sole image input device in all applications combined. Techniques and accessories to further increase the functionality of the camera and help overcome some of the commonly encountered problems in some applications are described. 相似文献
55.
Meghna R Adhvaryu Narshimha Reddy Minoo H Parabia 《African journal of traditional, complementary, and alternative medicines》2008,5(4):409-418
The anti-tumor activity and chemopreventive potential of four Ayurvedic herbs viz. Curcuma longa L., Ocimum sanctum L., Tinospora cordifolia (Wild) Miers ex Hook.f & Thomas and Zizyphus mauritiana Lam. were evaluated using Dalton Lymphoma ascites (DLA) tumor model in Swiss Albino mice. The outcome was assessed using survival time, peritoneal ascitic fluid (Tumor volume) and hematological indices as parameters. Animals were divided into five groups (n = 6) viz. one DLA control and four Herb + DLA treated groups. All the four herb + DLA groups were pre-treated with respective herbs for 7 days and hematological indices were measured for entire five groups. On day-8 animals were inoculated with 1×106 DLA cells i.p., and Herb + DLA groups were continued with oral herbal treatment for 21-days. Hematological parameters and tumor volume were assessed to find the effects of herbs. Short term in vitro cytotoxicity was determined by Trypan Blue exclusion method and LDH leakage assay using different concentrations of herbal extracts and 5-FU as a positive control and IC50 for each herbal extract and 5-FU were determined. Oral administration of crude herb increased the survival time and decreased the peritoneal ascitic fluid content significantly. Hb, RBCs and total WBC which were altered by DLA inoculation were restored significantly by all the herbs except O. sanctum. All the four herbs showed in vitro cytotoxic activity against DLA cell-line. Moreover inter group comparison of all the four herbs for anti-tumor activity showed efficacy in the following order- T. cordifolia > Z. mauritiana ≥ C. longa > O. sanctum respectively. 相似文献
56.
Study on the anatomical dimensions of the human sigmoid colon 总被引:4,自引:0,他引:4
Bhatnagar BN Sharma CL Gupta SN Mathur MM Reddy DC 《Clinical anatomy (New York, N.Y.)》2004,17(3):236-243
Although the sigmoid colon is commonly afflicted with disease, studies on its anatomical dimensions are scarce. It is suspected that dimensions of the sigmoid colon change with age. This study documents data on the anatomical measurements of the sigmoid colon in 70 Indian subjects (51 live and 19 cadavers). Seven parameters of sigmoid colon anatomy measured included length and width of the sigmoid colon and mesocolon at specific points. Three mesocolic indices (width to length ratios) were calculated. Comparisons of measurements in the live and cadaver subjects and in the two sexes were made. The relationship of change in parameters with age was assessed. Appropriate statistical methods were used and the differences were considered significant at P < or = 0.05. The study showed wide ranging variations in the values of various measured parameters of the sigmoid colon. Seven patterns of the shape of the sigmoid loop were identified. In the commonest pattern the sigmoid mesocolon was vertically longer than wide (dolichomesocolic), the sigmoid loop having its maximum convexity located just a little proximal to the apex. Patterns where the width of the mesocolon was greater than the vertical length (brachymesocolic) were also observed. The gender analysis showed that the sigmoid mesocolon of the female was brachymesocolic (wider than long), whereas that of the male was dolichomesocolic (longer than wide). This might explain the higher incidence of sigmoid volvulus in the male. This study also showed that the measurements of the sigmoid colon and its mesocolon do not change significantly within the age range of 16-60 years in the two sexes. Also noteworthy is the observation that in the cadaver the sigmoid colon shows considerable shrinkage, particularly of its mesocolon; consequently the data from cadaver subjects, though valuable for anthropometric use, have limitations when used for clinical applications. 相似文献
57.
Role of Periductal and Ductular Epithelial Cells of the Adult Rat Pancreas in Pancreatic Hepatocyte Lineage: A Change in the Differentiation Commitment 总被引:4,自引:8,他引:4
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M. Sambasiva Rao Rama S. Dwivedi Anjana V. Yeldandi V. Subbarao Xiaodi Tan Mohammed I. Usman Shobha Thangada Mohan R. Nemali Sujata Kumar Dante G. Scarpelli Janardan K. Reddy 《The American journal of pathology》1989,134(5):1069-1086
Development of pancreatic hepatocytes in adult rats maintained on copper deficient diet containing 0.6% trien (CuDT) has been reported recently. To elucidate the histogenesis of hepatocytes a sequential study was undertaken using morphologic, histochemical, immunochemical, in situ hybridization, and Northern blot analysis. Male F-344 rats weighing 80 to 90 g were fed CuDT for 8 weeks and returned to normal rat chow. Beginning from 4 weeks of copper depletion, there was a progressive loss of acinar cells and by 8 weeks more than 90% of the acinar tissue was lost. During this period, there was an increase in the number of adipocytes in the interstitium, and in the number of interstitial and ductular cells. Morphologic observations were confirmed by immunoblot and Northern blot analysis, in which the amount of pancreatic proteins and their mRNAs decreased between 5 and 8 weeks. During this period, a progressive increase in the level of albumin mRNA was observed. In situ hybridization, performed at 7 weeks of copper deficiency, showed localization of albumin mRNA over interstitial and ductular cells. Pancreatic hepatocytes were identified immediately after the rats were returned to a normal diet and gradually increased in number. The hepatocytes occupied almost 60% of the pancreatic volume by 8 weeks. During the early recovery phase, hepatocytes were identified in ductules as well as in the interstitium. Based on these studies, it is concluded that both the ductular cells and interstitial cells, which resemble oval cells of liver, are capable of transforming into pancreatic hepatocytes and these cells may be considered stem-cell equivalent. 相似文献
58.
Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
59.
60.
Sala F Mulet J Reddy KP Bernal JA Wikman P Valor LM Peters L König GM Criado M Sala S 《Neuroscience letters》2005,373(2):144-149
The effects of various Flustra foliacea metabolites on different types of human neuronal nicotinic acetylcholine receptors (nAChRs) expressed in Xenopus oocytes were investigated. Whereas most of the compounds tested had a small blocking effect, one of them, deformylflustrabromine, selectively increased the current obtained in alpha4beta2 receptors when co-applied with acetylcholine (ACh). The current increase was reversible and concentration-dependent. This potentiating effect was still present at saturating concentrations of acetylcholine, and no changes in single-channel conductance or reversal potential were observed, thus suggesting a modification in the gating of alpha4beta2 receptors. Dwell time analysis of single channel records indicates that the mechanism of action of deformylflustrabromine could be both an increase of the opening rate constant and a decrease of the closing rate constant on alpha4beta2 receptors. Thus, deformylflustrabromine may constitute an excellent starting point for the future development of related agents able to potentiate human neuronal nicotinic receptor function. 相似文献