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排序方式: 共有973条查询结果,搜索用时 15 毫秒
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BACKGROUND: Involvement of mesenteric vessels in intestinal tuberculosis and its role in the pathogenesis of the intestinal changes have not been studied histologically. AIM: To study mesenteric vessels in patients undergoing surgery for complications of intestinal tuberculosis. METHODS: Resected intestinal specimens from 68 patients presenting with intestinal perforation and intestinal obstruction were examined; involvement of the major mesenteric vessels was evaluated. RESULTS: Granulomas were seen in the vessel wall in one case and near the vessel wall in 11 cases, intraluminal thrombi were seen in 23 cases, and subintimal fibrosis in nine cases. Perivascular cuffing was seen in intramural and subserosal vessels in ten cases. CONCLUSIONS: Changes in the vessel wall may lead to gut ischemia, which may contribute to the development of strictures and stercoral perforation in intestinal tuberculosis. 相似文献
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Raja Fawad Zafar Michael B. C. Khoo Sajal Saha Zhi Lin Chong 《Quality and Reliability Engineering International》2021,37(6):2329-2333
The progressive mean (PM) statistic is based on a simple idea of accumulating information of each subgroup by calculating the average progressively. Its weighting structure is based on a subgroup number that changes arithmetically, which makes the PM chart unique and efficient compared with the existing classical memory control charts. In a recent article (see reference 1), it was claimed that the PM chart is a special case of the exponentially weighted moving average (EMWA) chart. In this article, it is shown that even though the PM statistic can be written in the form of an EWMA statistic, the variance of the PM statistic is different from that of the EWMA statistic. Consequently, the limits of the PM chart are different from that of the EWMA chart. Therefore, it is found that the PM chart is not a special case of the EWMA chart; hence, the claim in reference 1 is incorrect. Furthermore, it is pointed out in this paper that no adaptive property in the weighting parameter of the PM statistic exists, further contradicting the claim in reference 1. 相似文献
76.
YG Zorbas YY Yaroshenko NK Kuznetsov SL Matvedev 《Canadian Metallurgical Quarterly》1998,64(1-3):259-273
The aim of this study was to evaluate the effect of a daily intake of fluid and salt supplementation (FSS) on the deficiency of electrolytes, which is characterized by higher rather than lower plasma concentration of electrolytes during prolonged hypokinesia (HK) (decreased number of km taken per day). Forty long distance runners aged 22-25 yr with a peak VO2 65.4 mL min(-1) kg(-1) with an average 14.2 km d running distance were selected as subjects. They were equally divided into four groups: 1) unsupplemented control subjects (UCS); 2) unsupplemented hypokinetic subjects (UHS); 3) supplemented hypokinetic subjects (SHS), and 4) supplemented control subjects (SCS). During the investigation of 364 d, groups 2 and 3 maintained an average running distance of less than 4.7 km per day, groups 1 and 4 did not experience any modification in their normal training routines and diets. During the preexperimental period of 60 d and during the experimental period of 364 d urinary excretion of electrolytes and concentrations of sodium, potassium, calcium, and magnesium in plasma were determined. Whole blood hemoglobin, hematocrit index, plasma osmolality, and plasma protein concentration were measured. In the UHS plasma concentration of electrolytes and urinary excretion thereof, fluid elimination, hematocrit, whole blood hemoglobin, plasma osmolality, and plasma protein concentration increased significantly (p < 0.05) when compared with the UCS, SCS, and SHS groups. In the SHS plasma concentration of electrolytes and urinary excretion thereof, fluid excretion, whole blood hemoglobin, hematocrit, plasma osmolality, and plasma protein concentration decreased when compared with the UHS and increased insignificantly when compared with the UCS and SCS groups. It was concluded that FSS may be used to prevent or minimize electrolyte deficiency in endurance-trained volunteers during prolonged restriction of muscular activity. 相似文献
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Huay Woon You Michael B. C. Khoo Philippe Castagliola Abdul Haq 《Quality and Reliability Engineering International》2016,32(5):1913-1927
Many quality characteristics have means and standard deviations that are not independent. Instead, the standard deviations of these quality characteristics are proportional to their corresponding means. Thus, monitoring the coefficient of variation (CV), for these quality characteristics, using a control chart has gained remarkable attention in recent years. This paper presents a side sensitive group runs chart for the CV (called the SSGR CV chart). The implementation and optimization procedures of the proposed chart are presented. Two optimization procedures are developed, i.e. (i) by minimizing the average run length (ARL) when the shift size is deterministic and (ii) by minimizing the expected average run length (EARL) when the shift size is unknown. An application of the SSGR CV chart using a real dataset is also demonstrated. Additionally, the SSGR CV chart is compared with the Shewhart CV, runs rules CV, synthetic CV and exponentially weighted moving average CV charts by means of ARLs and standard deviation of the run lengths. The performance comparison is also conducted using EARLs when the shift size is unknown. In general, the SSGR CV chart surpasses the other charts under comparison, for most upward and downward CV shifts. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
78.
Essential contribution of caspase 3/CPP32 to apoptosis and its associated nuclear changes 总被引:1,自引:0,他引:1
M Woo R Hakem MS Soengas GS Duncan A Shahinian D K?gi A Hakem M McCurrach W Khoo SA Kaufman G Senaldi T Howard SW Lowe TW Mak 《Canadian Metallurgical Quarterly》1998,12(6):806-819
Caspases are fundamental components of the mammalian apoptotic machinery, but the precise contribution of individual caspases is controversial. CPP32 (caspase 3) is a prototypical caspase that becomes activated during apoptosis. In this study, we took a comprehensive approach to examining the role of CPP32 in apoptosis using mice, embryonic stem (ES) cells, and mouse embryonic fibroblasts (MEFs) deficient for CPP32. CPP32(ex3-/-) mice have reduced viability and, consistent with an earlier report, display defective neuronal apoptosis and neurological defects. Inactivation of CPP32 dramatically reduces apoptosis in diverse settings, including activation-induced cell death (AICD) of peripheral T cells, as well as chemotherapy-induced apoptosis of oncogenically transformed CPP32(-/-) MEFs. As well, the requirement for CPP32 can be remarkably stimulus-dependent: In ES cells, CPP32 is necessary for efficient apoptosis following UV- but not gamma-irradiation. Conversely, the same stimulus can show a tissue-specific dependence on CPP32: Hence, TNFalpha treatment induces normal levels of apoptosis in CPP32 deficient thymocytes, but defective apoptosis in oncogenically transformed MEFs. Finally, in some settings, CPP32 is required for certain apoptotic events but not others: Select CPP32(ex3-/-) cell types undergoing cell death are incapable of chromatin condensation and DNA degradation, but display other hallmarks of apoptosis. Together, these results indicate that CPP32 is an essential component in apoptotic events that is remarkably system- and stimulus-dependent. Consequently, drugs that inhibit CPP32 may preferentially disrupt specific forms of cell death. 相似文献
79.
We report a 14 year old boy who presented as a neonate with functional pulmonary atresia due to Uhl's disease with emphasis on the later detection of restrictive right ventricular physiology. 相似文献
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