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41.
Opinion statement  
–  6-Mercaptopurine and its prodrug counterpart, azathioprine, have proven efficacy in the induction and maintenance of remission, fistula closure, and steroid sparing in patients with Crohn’s disease. Long-term follow-up has demonstrated the safety of the purine analogues, with no increased risk of malignancy. For patients with Crohn’s disease intolerant or unresponsive to azathioprine or 6-mercaptopurine, methotrexate has emerged as an effective alternative.
–  In patients with severe ulcerative colitis, intravenous cyclosporine is highly efficacious in the short term, and with the addition of azathioprine or 6-mercaptopurine to oral cyclosporine, long-term remission rates of 60% to 70% can be achieved. Azathioprine or 6-mercaptopurine therapy is effective in patients with steroid-dependent or steroid-refractory colitis and is valuable in maintaining remission. Neither methotrexate nor cyclosporine has been shown to be effective for maintenance therapy in patients with ulcerative colitis.
–  Current data are insufficient to recommend routine use of genetic or enzymatic testing of thiopurine methyltransferase or measurements of blood 6-thioguanine metabolites to guide 6-mercaptopurine or azathioprine dosing.
  相似文献   
42.
Introduction: Increased stress levels have been reported and it has been implicated for mental illness amongst service personnel. However no study has been reported among Indian naval sailors.  相似文献   
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The effect of a central fusion lock on forced vergence fixation disparity curve parameters, that is, magnitudes of fixation disparity and associated phoria, curve type and the central slope of the curve, was studied in 84 subjects because of ambiguity in the previous studies. It was found that the magnitudes of exo fixation disparity and exo associated phoria decreased significantly when they were measured with the central fusion lock. The central lock had no noticeable effect on the type of the curve, although, the central slope of the curve was flatter in the presence of the central lock.  相似文献   
49.
Transient synovitis of the hip in children: role of US   总被引:7,自引:0,他引:7  
Transient synovitis of the hip remains a common diagnostic problem for the clinician. The physical signs are not pathognomonic of the condition, and the classic technical examinations are of little help. Therefore, the authors retrospectively studied the value of hip arthrosonography in 46 children with clinical symptoms suggesting pathologic hip conditions. In 20 of the 21 patients with a final diagnosis of transient synovitis, articular effusion was detected on ultrasound (US). Conventional radiography showed an increased medial joint space in only eight of these patients. Increased echogenicity of the articular fluid was found in both transient synovitis and septic arthritis. The high sensitivity of US in detecting intraarticular fluid was demonstrated by cadaver studies.  相似文献   
50.
Strains of the Mycobacterium avium complex (MAC) yield opaque and transparent colonial variants when cultivated in vitro. The transparent variants are more virulent than the opaque for animals, but little is known about the respective roles of these colonial variants in humans. To assess which variant infects humans, various blood fractions from eight patients with MAC bacteremia were plated directly onto 7H10 agar. In cell fractionation studies, all the M. avium complex CFU were associated with leukocytes and none were found free in plasma. All colonies on the primary culture plate exhibited the transparent phenotype. However, during subculture in 7H9 broth or on Lowenstein-Jensen agar, opaque variants appeared in seven of eight strains. Isogenic pairs of transparent and opaque variants were prepared and used to infect in vitro human monocyte-derived macrophages from healthy seronegative individuals. Transparent variants invariably grew inside macrophages, but only one of seven opaque variants did so. These observations indicate that the bacteremia of M. avium complex in acquired immunodeficiency syndrome patients consists exclusively of the transparent variants, perhaps because these variants are able to multiply inside macrophages. In contrast, opaque variants appear after in vitro subculture and are controlled by human macrophages, consistent with their reduced virulence in animals.  相似文献   
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