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排序方式: 共有5494条查询结果,搜索用时 15 毫秒
1.
Umar Nadia K. Badshah Maaz B. Sandrasegaran Kumar Ghabril Marwan Agarwal Saurabh Tann Mark Lacerda Marco Kwo Paul Y. 《Digestive diseases and sciences》2015,60(7):2196-2200
Digestive Diseases and Sciences - To determine whether the presence of portal vein thrombosis (PVT) where venous flow within the liver may be altered may delay the diagnosis of HCC and be... 相似文献
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Surender Kumar Yachha Rakesh Aggarwal S Srinivas Anshu Srivastava Sanjay K Somani Srivenu Itha 《Indian journal of gastroenterology》2006,25(3):132-135
BACKGROUND: We prospectively evaluated the usefulness of IgA tissue transglutaminase antibodies (IgA tTG) in the initial diagnosis of celiac disease (CD) and compared its diagnostic potential with that of IgA anti-endomysial antibodies (IgA EMA) and anti-IgA and IgG gliadin antibodies (AGA and AGG, respectively). METHODS: Sera of 23 untreated children fulfilling the revised ESPGHAN criteria for diagnosis of CD (Group I; mean age 10.8 y); 19 disease controls (Group II; mean age 8.5 y) presenting with chronic diarrhea, short stature or both; and 22 healthy children (Group III; mean age 8.8 y) were studied. These were tested in a blinded manner for AGA, AGG, IgA tTG (guinea pig as antigen) and IgA EMA. RESULTS: In Group I, IgA EMA was positive in 19, IgA tTG in 17, AGA in 14 and AGG in 17 patients. In Group II, these tests were positive in 1, 0, 2 and 14 patients, respectively and in Group III, in 0, 0, 0 and 1 child, respectively. Analyzing data from Group I and II, IgA EMA, IgA tTG, AGA and AGG had sensitivity rates of 83%, 74%, 61% and 74%, respectively; the specificity rates were 95%, 100%, 89% and 26%; positive predictive values were 95%, 100%, 88% and 55% and negative predictive values were 82%, 74%, 65% and 45%, respectively. CONCLUSION: IgA tTG is useful for the diagnosis of CD, with sensitivity and specificity rates comparable to those of EMA and this test is well suited for use in tropical countries like India. 相似文献
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P Aggarwal S K Sharma A B Dey T K Chattopadhyay M Mathur 《Postgraduate medical journal》1989,65(770):929-931
A case of malignant fibrous histiocytoma of the mediastinum presenting with unusual features of fever and leucocytosis is reported. This is the youngest patient reported in the literature who had this tumour in the mediastinum. 相似文献
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Nitin Gupta Saurabh Varshney S. S. Bist Pratima Gupta Rajat Bhatia 《Indian journal of otolaryngology and head and neck surgery》2007,59(4):309-312
Retropharyngeal abscesses were fairly common in preantibiotic era but the advent of antibiotics has reduced the overall incidence
of these abscesses. They still continue to occur specially in developing world and carry significant morbidity and even mortality
if not managed properly. The prevalence of this abscess in the young children pose a bigger challenge, as the examination
of oral cavity is difficult. Emphasis is placed on the age, sex, type, and duration of symptoms, bacteriology, methodology
of diagnosis, therapy and complications. With proper antibiotic cover and surgical management, majority of patients today
survive without major residual squeal. Hereby we present a series of 15 cases of retropharyngeal abscess. 相似文献
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Dhawan Subhash; Puri Raj K.; Kumar Ashok; Duplan Helen; Masson Jean-Michel; Aggarwal Bharat B. 《Blood》1997,90(4):1535-1544
10.
Synthesis and biological evaluation of prodrugs of zidovudine 总被引:4,自引:0,他引:4
A series of prodrugs of zidovudine (AZT) has been synthesized in an effort to enhance the uptake of the prodrugs by the HIV-1 infected cells and to increase the plasma half-life of AZT. The 5'-OH function of AZT was esterified with various acids in the presence of DCC and 4-(dimethylamino)pyridine (DMAP). The prodrug moieties included (a) morpholine and N-phenylpiperazine-1-acetic acid, (b) 1,4-dihydro-1-methyl-3-nicotinic acid, (c) retinoic acid, and (d) certain amino acids. The anti-HIV-1 activity of the esters was determined in peripheral blood lymphocytes. The IC50 for AZT in this system was 0.12 microM whereas for prodrugs it ranged from 0.05 to 0.2 microM. The prodrugs were generally less cytotoxic than AZT except the retinoic acid ester. In vitro hydrolysis of the various esters in human plasma indicated that these agents were relatively stable toward plasma esterases with t1/2 ranging from 10 to 240 min. Drug uptake studies in H9 cells with radiolabeled analogues demonstrated that the retinoic acid ester achieved approximately 4-fold higher intracellular concentration than [3H]AZT. However, 1,4-dihydro-1-methyl-3-[(pyridylcarbonyl)oxy] ester (5) was the most active agent of this series and had a higher therapeutic index than AZT. 相似文献