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101.
Ximena Calderón‐Castrat M.D. Rosa Castro M.D. Johanna Peceros‐Escalante M.D. Marjorie Villate Caballero M.D. Cesar Chian M.D. Rosalía Ballona M.D. 《Pediatric dermatology》2017,34(3):e109-e115
Pediatric Degos disease is rare, with only 36 cases reported in the medical literature. Classically the diagnosis has been established according to pathognomonic histopathologic findings, but when these features are not present, there may be a delay in diagnosis. We report the second congenital case of Degos disease, highlighting the clinical and dermoscopic findings. 相似文献
102.
Mark A. Halsey Kenneth B. Calder Rahel Mathew Scott Schlauder Michael B. Morgan 《Journal of cutaneous pathology》2010,37(4):446-451
Background: α‐Methylacyl‐CoA racemase (AMACR), also known as P504S, is a protein that plays an important role in mitochondrial and peroxisomal β‐oxidation of branched‐chain fatty acid and bile acid intermediates. AMACR has been established as a valuable diagnostic marker for prostate cancer and has recently been shown to be useful in the diagnosis of colorectal carcinoma. Despite the importance of lipid metabolism in sebum production by sebaceous glands of the skin, there are no studies evaluating the expression of AMACR in sebaceous neoplasms. Methods: Five samples of normal sebaceous glands as well as five cases each of sebaceous hyperplasia (SH), sebaceous adenoma (SA), basal cell carcinoma (BCC) with sebaceous differentiation and extraocular sebaceous carcinoma (SC) were evaluated for immunohistochemical (IHC) expression of AMACR. Each case was reviewed by a single dermatopathologist and graded using a semi‐objective grading schema. Results: Normal sebaceous glands showed strong (4+) expression of AMACR. Among sebaceous neoplasms, SH showed the highest expression (4+), SA and BCC with sebaceous differentiation showed varied expression (2+ and 1+, respectively), and extraocular SC showed no expression of AMACR. Conclusions: The expression of AMACR is increased in benign sebaceous glands and SH; with decreasing AMACR expression in tumors with less sebaceous differentiation (i.e. SA and SC). These findings provide insight into the potential pathogenesis of sebaceous neoplasms while assisting in the microscopic distinction of SA from SC. Halsey MA, Calder KB, Mathew R, Schlauder S, Morgan MB. Expression of α‐methylacyl‐CoA racemase (P504S) in sebaceous neoplasms. 相似文献
103.
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105.
Christopher J. Pearce James D. Calder 《Knee surgery, sports traumatology, arthroscopy》2010,18(5):581-586
The midfoot plays a vital role in the stability of the foot as a whole. Injuries to the midfoot may be subtle and can lead
to significant long-term morbidity, especially where there is a delay in diagnosis and treatment. This article describes the
anatomy of the midfoot that is relevant to surgical practice. It should provide the reader with an understanding of how the
anatomy of the midfoot relates to its function as well as discussing the anatomical considerations of injuries and surgery
in this area. Anatomical knowledge aids clinical practice in terms of the recognition of abnormalities and the guidance of
treatment. 相似文献
106.
Gierer IM Abdala O Calderón C Risoli E Cravero A Pinchuk L 《Acta gastroenterologica Latinoamericana》2000,30(5):511-514
The cholestasis by meloxicam has not been often described. However, we present here the clinic, laboratory, histologic and follow up of a patient with cholestatic hepatitis produced by this drug. 相似文献
107.
108.
Fortún J Perez-Molina JA Asensio A Calderón C Casado JL Mir N Moreno A Guerrero A 《JPEN. Journal of parenteral and enteral nutrition》2000,24(4):210-214
BACKGROUND: Sensitivity and negative predictive values of combined surface cultures (skin and hub) are high in the presumptive diagnosis of catheter-related infection, but specificity and PPVs are poor. The purpose of the study was to evaluate the yield of the semiquantitative culture of the subcutaneous segment in the diagnosis of colonization of the catheter tip without removal of the catheter. METHODS: A prospective study was performed in 124 nontunneled central venous catheters that were removed because of suspected infection or the end of therapy. Catheter colonization was considered if >15 colony-forming units (CFU) in the roll procedure or > 1,000 CFU in the quantitative Cleri procedure were recovered from the tip cultures ("gold standard"). Before removing the catheter, a semiquantitative culture of skin surrounding the point of insertion, a semiquantitative culture of the subcutaneous segment (after removing the catheter only 2 cm), a semiquantitative cultures of the hub, and a pareated quantitative blood culture were performed. Receiver operating characteristic curves were calculated to estimate the cutoff points, and a culture was considered positive when CFUs were > or =15, > or =15, and > or =5 for skin, hub, and subcutaneous segment cultures, respectively. RESULTS: Catheter colonization was detected in 51 catheters. The mean duration of catheterization was 14 +/- 8 days, and the rates of incidence of tip colonization and bacteremia were 2.9 per 100 catheter days and 1.2 per 100 catheter days, respectively. Sensitivity of skin, subcutaneous, and hub cultures analyzed individually were < or =61%; however, specificity and positive predictive values (PPVs) of subcutaneous segment cultures were significantly higher than skin cultures (94% and 88.5% vs 71.6% (p = .001) and 62% (p = .014), respectively). Sensitivity of the combined skin and hub cultures and of the combined subcutaneous segment and hub cultures were similar: 86.2% and 84.3%, respectively; however, specificity and PPVs of this latter combination were significantly higher than former: 82% and 78.1% vs 59.7% (p = .008) and 61.9% (p = .07), respectively. The likelihood ratio of a positive test for the combined subcutaneous segment and hub culture was 4.68, and only 2.13 for the combined skin and hub culture. CONCLUSIONS: These results indicate that the combined subcutaneous segment and hub culture constitutes an easy, effective procedure for the conservative diagnosis of catheter colonization. 相似文献
109.
Graham ID Calder LA Hébert PC Carter AO Tetroe JM 《International journal of technology assessment in health care》2000,16(4):1024-1038
OBJECTIVE: To identify and compare clinical practice guideline appraisal instruments. METHODS: Appraisal instruments, defined as instruments intended to be used for guideline evaluation, were identified by searching MEDLINE (1966-99) using the Medical Subject Heading (MeSH) practice guidelines, reviewing bibliographies of the retrieved articles, and contacting authors of guideline appraisal instruments. Two reviewers independently examined the questions/statements from all the instruments and thematically grouped them. The 44 groupings were collapsed into 10 guideline attributes. Using the items, two reviewers independently undertook a content analysis of the instruments. RESULTS: Fifteen instruments were identified, and two were excluded because they were not focused on evaluation. All instruments were developed after 1992 and contained 8 to 142 questions/statements. Of the 44 items used for the content analysis, the number of items covered by each instrument ranged from 6 to 34. Only the instrument by Cluzeau and colleagues included at least one item for each of the 10 attributes, and it addressed 28 of the 44 items. This instrument and that of Shaneyfelt et al. are the only instruments that have so far been validated. CONCLUSIONS: A comprehensive, concise, and valid instrument could help users systematically judge the quality and utility of clinical practice guidelines. The current instruments vary widely in length and comprehensiveness. There is insufficient evidence to support the exclusive use of any one instrument, although the Cluzeau instrument has received the greatest evaluation. More research is required on the reliability and validity of existing guideline appraisal instruments before any one instrument can become widely adopted. 相似文献
110.
Sulfhydryl group donors, such as N-acetylcysteine (NAC), may enhance the antihypertensive effect of some drugs through a nitric oxide (NO) mechanism. It has been observed that the hypotensive effect of angiotensin-converting enzyme inhibitors (ACEIs) is, at least partially, mediated by NO. We performed a within patient crossover study with the aim to investigate the potential effect of NAC on the ACEI antihypertensive action, via an NO-dependent mechanism. We studied 18 smoker (> 10 years of habit and > 10 cigarettes daily) hypertensive patients (15 males and three females, aged 69 +/- 5 years) on ACEI therapy (11 captopril and seven enalapril). Patients were randomly allocated to two treatment arms. In one arm, the patients (n = 10) initially received the addition of NAC (600 mg t.i.d.) to the ACEI regimen. In the other group (n = 8), the patients remained only on ACEI. After 21 days, the therapeutic patterns were crossed. The first group received only ACEI, and the second group received ACEI and NAC and completed other 21-day treatment period. We evaluate the effect of NAC on each patient by ambulatory blood pressure monitoring (ABPM), performed at the end of each therapeutic regimen. A significant decrease in systolic and diastolic 24-h blood pressure (24 hBP) and daytime BP (dtBP) was achieved with the combination of ACEI and NAC (ACEI + NAC) when compared to the period with only ACEI: 24 hBP = 146.1 +/- 4.2 vs 137 +/- 3.1 (p < 0.05) and 89.2 +/- 2.8 vs 83.5 +/- 3.7mmHg (p = 0.01). DtBP: 149.7 +/- 5.6 vs 141 +/- 3.7 and 92.1 +/- 4 vs 86 +/- 3.2 (both, p < 0.05). No significant difference was observed in night-time BP (ntBP). The NAC effect was not statistically different for the two ACEIs. In conclusion, the addition of NAC to an ACEI potentiates its antihypertensive effect during 24hBP and dtBP in smoker hypertensives. This effect may be mediated by an NO-dependent mechanism, probably through the protective effect of NAC on NO oxidation. 相似文献