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141.
Severity of arsenic toxicity was reported to vary depending on its species. The present study reflects the status of different species of arsenic in goat following long-term exposure of arsenic leading to hepatic damage. The experiment was conducted with six black Bengal goats, which were administered with sodium arsenite orally at a dose rate of 2 mg kg−1 daily for 84 days. Faeces, urine, hair and blood samples were collected from those animals at 14 days interval. Excretion of total arsenic was reduced from 56 days onwards through both faeces and urine indicating higher accumulation of arsenic in body. The speciation study revealed that urinary arsenic was mainly of organic type, whereas hair accumulated almost equal proportion of arsenite, arsenate and organo arsenicals. Goats excreted high proportion of organo arsenicals through faeces possibly due to hepatobiliary secretion of organo arsenic into the gut. Significantly elevated serum alanine aminotransferase and aspartate aminotransferase activities (p < 0.05) alongwith histopathological changes in liver indicated hepatotoxicity. The arsenite fraction increased and organic proportion decreased in urine as the time progressed, which indicates that arsenite gets methylated in liver of goat. The study thus alluded that the toxicity of arsenic would aggravate if the animals were exposed for long time as the hepatotoxicity progressed resulting in decreased methylation and formation of organo arsenicals and decreased excretions through urine.  相似文献   
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The objective of the present work was to propose a method for calculating weight in the Moore and Flanner Equation. The percentage coefficient of variation in reference and test formulations at each time point was considered for calculating weight. The literature reported data are used to demonstrate applicability of the method. The advantages and applications of new approach are narrated. The results show a drop in the value of similarity factor as compared to the approach proposed in earlier work. The scientists who need high accuracy in calculation may use this approach.  相似文献   
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Intravascular lymphoma (IVL) is a rare neoplastic disease characterized by the presence of large malignant lymphoid cells in small vessels. It is often diagnosed at autopsy. Clinical manifestations are typically neurologic and dermatologic. Karyotypic abnormalities have been described in a small number of cases and have revealed complex alterations in the majority of cases. We have identified three cases of IVL with varied clinicopathological findings. Karyotypic analysis was undertaken by standard G-banding and supplemented by multi-colored karyotyping (M-FISH) to decipher the chromosomal content of marker chromosomes and undefined additions. M-FISH clarified the chromosomal abnormalities in two cases and unveiled cryptic translocations der(10)t(10;22), der(17)t(17;22), and balanced t(11;14). Comparison with previously published karyotypes revealed prominent involvement of chromosomes 1, 3, 6, 11, 14, and 18, similar to the pattern of clonal evolution in other B-cell lymphomas. The most frequent alterations seen were -6 or 6q- and +18 or dup(18q), with a minimally deleted region located at 6q21-q23 and a commonly amplified region located at 18q13-q23, respectively. Few differences between the classical and Asian variant of this disease were apparent at the karyotypic level. Cytogenetic analysis of additional cases supplemented by multicolor karyotyping may help identify the full spectrum of genetic alterations associated with IVL and assist in the delineation of the critical mutations associated with initiation and progression of this disease.  相似文献   
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OBJECTIVE: The aim of this study was to investigate the importance of venous reflux in ulcer recurrence following saphenous surgery. METHODS: Ulcerated legs (CEAP 5 and 6) with saphenous reflux were treated with superficial venous surgery plus compression as part of a clinical trial. Patients unfit for general anaesthesia (GA) underwent limited surgery under local anaesthesia (LA). Reflux in superficial and deep segments and venous refill times (VRTs) were assessed before surgery and 3-12 months post-operatively using duplex and digital photoplethysmography respectively. RESULTS: Of 185 patients treated with surgery, 15 failed to heal and 26 did not have a follow-up duplex. Within 3 years, 25 of the remaining 144 patients (17%) developed ulcer recurrence. Using a Cox regression model, the presence of residual venous reflux and change in reflux pattern were not found to be risk factors for ulcer recurrence (p=ns). LA was used in 4/25 patients who recurred compared to 28/119 who did not (p=0.60; Chi-square test). For legs with recurrence, median VRT before surgery was 10.5s (range 5-29) compared to 11s (range 6-36) after surgery (p=0.097, Wilcoxon Signed Rank test). However, in legs without recurrence, median VRT increased from 10s (range 3-48) to 15s (range 4-48) after surgery (p<0.001). CONCLUSION: Residual reflux following saphenous surgery is not the most important predictor of venous ulcer recurrence. Poor venous function as demonstrated by VRT may be a better predictor of recurrence in these patients.  相似文献   
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With the increasing use of double-contrast technique in radiological evaluation of the gastrointestinal tract, certain artifacts peculiar to this mode of examination need to be identified. These artifacts arise because of: (a) the characteristics of the barium suspensions used for double-contrast studies; (b) the see-through effect obtained on double-contrast studies whereby opacities lying in front of or behind the organ being examined may simulate pathologic lesions; (c) infolding of the mucosa which may simulate pathology; (d) extraneous or foreign material which is frequently detected and must be differentiated from intrinsic disease; (e) certain anatomical structures such as the cardia, pylorus, and retrogastric structures which are seen with unusual clarity and detail and which, in some cases, may simulate pathology. In general, these artifacts may simulate diffuse superficial ulceration, discrete ulceration, or polypoid lesions. Familiarity with the double-contrast technique and an understanding of these artifacts will help to avoid diagnostic errors.  相似文献   
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