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1.
Metabolic abnormalities of gastrointestinal mucosa in celiac disease: An in vitro proton nuclear magnetic resonance spectroscopy study 下载免费PDF全文
2.
Nand L. Sharma Vikram K. Mahajan Neelam Gupta Nitin Ranjan and Anju Lath 《Journal of cutaneous pathology》2009,36(4):486-492
Ehlers-Danlos syndrome – vascular type, the only lethal form, is rarely reported in dermatology literature. It is characterized by translucent, atrophic skin, easy bruising, arterial, intestinal and/or uterine fragility manifesting as varicose veins, aneurysms and vascular/visceral/uterine rupture. As its dermatopathologic features are not well elucidated, diagnosis is often made after a catastrophic complication or at autopsy. This 36 year-old non-consanguineous male had brown-black plaques with atrophy and frequent ulceration over legs and dorsal feet and tortuous varicose veins around ankles for the past 15 years. Perivenous skin was translucent and hypopigmented. He had multiple and ecchymotic keloids and small atrophic, pityriasis versicolor-like lesions over trunk. He did not have hypermobile/hyperextensible skin and joints and showed no systemic or investigative abnormality. Histopathologic features of atrophic lesion included blood extravasation in atrophic epidermis/dermis, focal clustering and dilatation of blood vessels, malformed vessel walls, abundant hemosiderin in the dermis and homogenously stained/whorled patterned collagen especially around blood vessels. Pathology of keloidal lesion showed new collagen and vascular fragility. These histopathologic features appear of diagnostic value especially in patients who have compatible clinical findings but cannot afford confirmation by biochemical testing for abnormal synthesis of type III procollagen or identification of mutations in the COL3A1 gene. 相似文献
3.
Brian F O'Reilly Ameet Kishore John A Crowther Colin Smith 《Otology & neurotology》2004,25(5):791-796
OBJECTIVE: To examine the relationship between growth rate of vestibular schwannomas and the expression of various growth factor receptors. STUDY DESIGN: Retrospective case review of clinical growth rate in conjunction with a histopathologic and immunohistochemical reexamination of archival specimens. SETTING: A tertiary referral neurotologic center. PATIENTS: Three groups: a historical group to act as controls, consisting of 30 patients with sporadic vestibular schwannomas removed before the unit adopted an initial interval scan policy; a group of 14 patients with sporadic vestibular schwannomas who had undergone an initial interval scan policy, showed radiologic evidence of growth, and therefore had their schwannoma removed; and a group of 16 schwannomas removed from 11 neurofibromatosis Type 2 patients. MAIN OUTCOME MEASURES: A comparison between the three clinical groups using immunohistochemical studies to determine the level of expression of the proliferation factor Ki-67, c-erbB-2, and c-erbB-3 receptors and fibroblastic growth factor receptors 1 and 4. RESULTS: The level of expression of the proliferation factor Ki-67 was very low and similar in all three groups. C-erbB-2 and c-erbB-3 receptors were not expressed in any of the groups. fibroblastic growth factor receptor 4 expression was not significantly different, but there was a variation in the expression of fibroblastic growth factor receptor 1 between the three groups that correlated well with the differing incidence of growth in the groups. The increase in expression of fibroblastic growth factor receptor 1 in the neurofibromatosis Type 2 group was not statistically significant, but the increase in expression of fibroblastic growth factor receptor 1 in the growing sporadic group was statistically significant when compared with the historical controls. The level of fibroblastic growth factor receptor 1 expression correlates significantly with the rate of growth as measured on interval magnetic resonance imaging. CONCLUSIONS: Overexpression of fibroblastic growth factor receptor 1 has a positive correlation with the incidence and the rate of growth of sporadic vestibular schwannomas. 相似文献
4.
Paolo R. Salvalaggio Katie Neighbors Susan Kelly Karan M. Emerick Kishore Iyer Riccardo A. Superina Peter F. Whitington Estella M. Alonso 《American journal of transplantation》2005,5(8):1868-1874
The Pediatric End-Stage Liver Disease (PELD) score was designed to reduce subjectivity in liver allocation and to advantage patients with a higher probability of waiting list mortality. The aims of this study were to determine the impact of PELD implementation for children with chronic liver disease and to assess whether PELD met its goal of standardization of liver allocation for children. This study used data reported to the United Network for Organ Sharing (UNOS) registry for children with chronic liver disease receiving primary cadaveric liver transplant between January 2000 and December 2001 (pre-PELD) and March 2002 and July 2003 (PELD). PELD reduced the percentage of children transplanted while in an intensive care unit and as status 1. A calculated PELD score was used for allocation in only 52% of recipients. Thirty percent were status 1 at transplant and PELD scores granted by exception were used for allocation in 18% of patients. There was regional variation in PELD score at allocation and use of exception scores with a significant relationship between PELD score and percentage of exception cases. Regional variation suggests that PELD has not resulted in standardization of listing practices in pediatric liver transplantation. 相似文献
5.
Sudhakar B. Ogale Satyabhushan Mahajan Kishore B. Sandu Nityananda Babu 《Indian journal of otolaryngology and head and neck surgery》1997,49(2):154-156
Tympanosclerosis (TS) is a common sequelae of chronic otitis media found in all age groups. Over a period of 3 years, out of 520 surgical cases, 68 (13%) were found to have varying amounts of Tympanosclerotic plaques (TSP) warranting surgical removal. 60% had extension of TSP over the ossicular chain thus affecting its mobility. Deliberate surgical removal of TSP was undertaken for hearing improvement. Systematic and meticulous removal of TSP rather than en-bloc removal has been found to improve the hearing as close to as in, non-tympanosclerotic ear surgery. 相似文献
6.
Inhibition of positively rewarding behavior by the heightened aggressive state evoked either by pain-inducing stimulus or septal lesion 总被引:1,自引:0,他引:1
Using a footshock elicited aggression paradigm, aggressive responses were scored in normal and in septal-lesioned adult male Wistar rats. Septal lesions were made electrolytically to include the medial and lateral septal nuclei. The lesion was confirmed by behavioral criteria (septal aggression) and post-mortem histology. The aggressive response types (threat, attack) of the septal animals were compared with their corresponding age and weight matched controls. Results showed a statistically significant increase (P = 0.05) in the number of attack responses but not the threat responses in septal animals. The modulatory role of the aggressive experience on responsiveness to positively rewarding or hedonic stimuli was assessed by quantifying the intracranial self-stimulation (SS) rates that were obtained before and after an aggression schedule. For testing the SS behavior bipolar electrodes were implanted in the ventral tegmental area--substantia nigra (VTA-SN). Results showed a decrease in SS pedal press rates in post-aggression schedule as compared to the pre-aggression period in the normal subjects. This depressing effect lasted for over a week. In septal lesioned rats the SS rates were virtually abolished even without having an aggressive schedule. These experiments revealed the effect of environment and of a brain area in provoking aggressive mood and its inhibitory consequence on responding for positive experience. 相似文献
7.
8.
AIMS--To evaluate a safe sputum processing method for detection of tuberculosis in developing countries. METHODS--A sample processing method was developed in which acid fast bacilli were killed with 1% sodium hypochlorite and concentrated by flotation on a layer of xylene before staining by the Ziehl Neelsen or auramine O methods. RESULTS--Best results were obtained by auramine O staining after flotation. Staining by the Ziehl Neelsen method after flotation gave better results than direct Ziehl Neelsen staining without flotation. CONCLUSIONS--The flotation method with Ziehl Neelsen staining offers advantages for smear preparation in the tuberculosis control programmes of developing countries. 相似文献
9.
Candida albicans and Saccharomyces cerevisiae expressing the adhesins Als5p or Als1p adhere to immobilized peptides and proteins that possess appropriate sequences of amino acids in addition to a sterically accessible peptide backbone. In an attempt to further define the nature of these targets, we surveyed the ability of yeast cells to adhere to 90- micro m-diameter polyethylene glycol beads coated with a 7-mer peptide from a library of 19(7) unique peptide-beads. C. albicans bound to ca. 10% of beads from the library, whereas S. cerevisiae expressing Als5p or Als1p bound to ca. 0.1 to 1% of randomly selected peptide-beads. S. cerevisiae expressing Als1p had a distinctly different adherence phenotype than did cells expressing Als5p. The former adhered in groups or clumps of cells, whereas the latter adhered initially as single cells, an event which was followed by the build up of cell-cell aggregates. Beads with adherent cells were removed, and the peptide attached to the bead was determined by amino acid sequencing. All adhesive beads carried a three-amino-acid sequence motif (tau phi+) that possessed a vast combinatorial potential. Adherence was sequence specific and was inhibited when soluble peptide identical to the immobilized peptide was added. The Als5p adhesin recognized some peptides that went unrecognized by Als1p. The sequence motif of adhesive peptides identified by this method is common in proteins and offers so many possible sequence combinations that target recognition by the Als proteins is clearly degenerate. A degenerate recognition system provides the fungi with the potential of adhering to a multitude of proteins and peptides, an advantage for any microorganism attempting to establish a commensal or pathogenic relationship with a host. 相似文献
10.