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21.
Silent cerebral infarctions have been shown to cause major morbidity in children with sickle cell disease, suggesting that silent infarctions are not as "silent" as once thought. The current definition of silent infarction includes signal changes on magnetic resonance imaging, the absence of overt abnormalities on neurologic examination, and no history of focal neurologic event. Using a decision tree algorithm, we identified a cognitive profile distinguishing children with (n=16) and without (n=49) silent infarctions. The best model combined learning slope from the California Verbal Learning Test-Children's Version and Block Design from the Wechsler Abbreviated Scale of Intelligence. Accuracy was 75%, with 75% sensitivity and 76% specificity. Administration of a brief cognitive battery may be the most feasible approach to screen for silent infarctions in children with sickle cell disease.  相似文献   
22.
Neuroendocrine (Merkel cell) carcinoma of the skin is a rare entity. Often locally aggressive, this lesion may also metastasize to organ systems, including bone, liver, and brain. The authors report a case of a 64-year-old male who presented with hoarseness and dysphagia 17 months after resection of a primary Merkel cell carcinoma of the nose. Additional studies revealed bilateral vocal cord paralysis secondary to central nervous system dysfunction. Cytologic evaluation of the cerebrospinal fluid revealed malignant tumor cells consistent with metastatic Merkel cell carcinoma. Presented are the cytologic and immunohistochemical findings in a case of metastatic Merkel cell carcinoma involving the central nervous system.  相似文献   
23.
The investigators report the clinical and pathologic features of 19 cases of intraepithelial neoplasia occurring in the anal canal mucosa of routinely excised hemorrhoidal tissue, a condition that has been infrequently described. The patients were 12 women and seven men having an age range of 21 to 74 years (mean, 48 years). Two patients had coexistent anogenital condylomata acuminata. Leukoplakia of the hemorrhoidal surface was noted in two patients. Intraepithelial neoplasia arose in the transition zone of the anal canal of 11 cases, in the squamous zone of three cases, and in both sites of five cases. All were high-grade intraepithelial neoplasms; one was classified moderate to severe dysplasia, 17 exhibited severe dysplasia/carcinoma in situ, and one contained microinvasive carcinoma. Both keratinizing and cloacogenic type neoplasms were observed. Associated koilocytotic atypia was identified in 16 cases (84%). In situ hybridization for human papillomavirus (HPV) messenger RNA demonstrated HPV RNA sequences in seven of nine neoplasms (78%) studied by that technique (five HPV type 16, one HPV type 18, and one coinfection with HPV types 6 and 18). Eighteen patients had no clinically evident recurrent or progressive disease at mean follow-up of 6.6 years. Residual/recurrent intraepithelial neoplasia was noted in one patient at 1, 2, 5, and 49 months posthemorrhoidectomy. Our data indicate that incidentally discovered high-grade intraepithelial neoplasia present in hemorroidal tissue is a clinically nonaggressive lesion frequently associated with HPV infection. Hemorrhoidectomy alone is curative in most cases.  相似文献   
24.
We conducted an adaptive design single‐center pilot trial between October 2017 and November 2018 to determine the safety and efficacy of ultra‐short‐term perioperative pangenotypic direct acting antiviral (DAA) prophylaxis for deceased hepatitis C virus (HCV)‐nucleic acid test (NAT) positive donors to HCV negative kidney recipients (D+/R?). In Group 1, 10 patients received one dose of SOF/VEL (sofusbuvir/velpatasvir) pretransplant and one dose on posttransplant Day 1. In Group 2A (N = 15) and the posttrial validation (Group 2B; N = 25) phase, patients received two additional SOF/VEL doses (total 4) on Days 2 and 3 posttransplant. Development of posttransplant HCV transmission triggered 12‐week DAA therapy. For available donor samples (N = 27), median donor viral load was 1.37E + 06 IU/mL (genotype [GT]1a: 70%; GT2: 7%; GT3: 23%). Overall viral transmission rate was 12% (6/50; Group 1:30% [3/10]; Group 2A:13% [2/15]; Group 2B:4% [1/25]). For the 6 viremic patients, 5 (83%) achieved sustained virologic response (3 with first‐line DAA therapy; and two after retreatment with second‐line DAA). At a median follow‐up of 8 months posttransplant, overall patient and allograft survivals were 98%, respectively. The 4‐day strategy reduced viral transmission to 7.5% (3/40; 95% confidence interval [CI]: 1.8%‐20.5%) and could result in avoidance of prolonged posttransplant DAA therapy for most D+/R ? transplants.  相似文献   
25.
We compared the roles of urinary cytology and flow cytometry in the evaluation of patients with bladder cancer in clinical practice situations at a large general hospital. Specimens included 105 bladder washings from patients being followed for urothelial carcinomas and 28 control washings from individuals undergoing cytoscopy for other reasons. Flow cytometry and cytology were performed on aliquots of the same specimen in all bladder cancer samples. When carcinoma was present at the time of specimen collection it was detected by positive cytology in 75 per cent and deoxyribonucleic acid aneuploidy in 78 per cent of the cases. Combination of flow cytometry and urinary cytology increased the diagnostic yield to 95 per cent. Flow cytometry was slightly more sensitive than urinary cytology for detection of abnormalities in specimens from noninvasive and untreated tumors but the only statistically significant difference between the 2 procedures occurred among specimens from treated invasive cancers in which flow cytometry was a less sensitive method than cytology. Abnormal deoxyribonucleic acid ploidy was documented in a few specimens from noncancer-bearing patients having diseases associated with high urothelial cell turnover rates but the concomitant urinary cytology was negative for neoplasia. When used in conjunction with urinary cytology, flow cytometry was a valuable procedure in the followup of patients with bladder cancer. The diagnostic yield with this combination was such that flow cytometry and cytology may be used to reduce the frequency of cystoscopy and biopsy during clinical management in selected situations.  相似文献   
26.
The experience at one institution concerning the diagnosis of pulmonary tuberculosis by aspiration biopsy is reviewed. Twelve cases in which acid-fast bacilli were identified in pulmonary aspiration material are reported. The cytologic findings were confirmed by microbiologic culture in nine cases. The advantages of using aspiration biopsy cytology in the diagnosis of pulmonary tuberculosis are discussed. In our experience we conclude that the use of aspiration biopsy cytology in the diagnosis of pulmonary tuberculosis is not only accurate, but also offers several advantages that are important in patient care.  相似文献   
27.
Area-level measures are often used to approximate socioeconomic status (SES) when individual-level data are not available. However, no national studies have examined the validity of these measures in approximating individual-level SES. Data came from ~ 3,471,000 participants in the Mortality Disparities in American Communities study, which links data from 2008 American Community Survey to National Death Index (through 2015). We calculated correlations, specificity, sensitivity, and odds ratios to summarize the concordance between individual-, census tract-, and county-level SES indicators (e.g., household income, college degree, unemployment). We estimated the association between each SES measure and mortality to illustrate the implications of misclassification for estimates of the SES-mortality association. Participants with high individual-level SES were more likely than other participants to live in high-SES areas. For example, individuals with high household incomes were more likely to live in census tracts (r = 0.232; odds ratio [OR] = 2.284) or counties (r = 0.157; OR = 1.325) whose median household income was above the US median. Across indicators, mortality was higher among low-SES groups (all p < .0001). Compared to county-level, census tract-level measures more closely approximated individual-level associations with mortality. Moderate agreement emerged among binary indicators of SES across individual, census tract, and county levels, with increased precision for census tract compared to county measures when approximating individual-level values. When area level measures were used as proxies for individual SES, the SES-mortality associations were systematically underestimated. Studies using area-level SES proxies should use caution when selecting, analyzing, and interpreting associations with health outcomes.  相似文献   
28.
Aspiration biopsy of mass lesions of the kidney is a diagnostic procedure whose potential benefit to patients with equivocal radiologic findings, suspected metastases, palpable flank masses, nonfunctioning kidneys and even cortical cysts has not been fully explored. Over the past 7 years 163 renal aspiration specimens from 152 patients have been examined. Diagnostic yield was enhanced by use of modified "fine" needles with notched tips so that tissue fragments for histology as well as smears for cytology were obtained in 89% of solid tumors. The availability of aspirated tissue contributed significantly to pathologic classification and often spared patients additional surgery for confirmation of the cytologic diagnosis. Among the 152 cases, there were 35 with renal cell carcinomas, a sufficient number for detailed semiquantitative evaluation of their cytologic features. The remaining cases comprised metastatic carcinomas, lymphomas, transitional cell carcinomas, oncocytomas, cortical cysts, and miscellaneous conditions, e.g., abscesses, nonfunctioning kidneys, and hematomas. Overall, the aspiration biopsy determined the nature of the renal mass in 141 cases (93%). False-negative interpretations were due to insufficient diagnostic material in all but one instance. There was one false-positive result.  相似文献   
29.
Anisotropy of mouse and human skin is investigated in vivo using polarized videoreflectometry. An incident beam (linearly polarized, wavelength 650 nm) is focused at the sample surface. Two types of tissuelike media are used as controls to verify the technique: isotropic delrin and highly anisotropic demineralized bone with a priori knowledge of preferential orientation of collagen fibers. Equi-intensity profiles of light, backscattered from the sample, are fitted with ellipses that appear to follow the orientation of the collagen fibers. The ratio of the ellipse semiaxes is well correlated with the ratio of reduced scattering coefficients obtained from radial intensity distributions. Variation of equi-intensity profiles with distance from the incident beam is analyzed for different initial polarization states of the light and the relative orientation of polarization filters for incident and backscattered light. For the anisotropic media (demineralized bone and human and mouse skin), a qualitative difference between intensity distributions for cross- and co-polarized orientations of the polarization analyzer is observed up to a distance of 1.5 to 2.5 mm from the entry point. The polarized videoreflectometry of the skin may be a useful tool to assess skin fibrosis resulting from radiation treatment.  相似文献   
30.
Acute thyroiditis is very unusual, and fungal thyroiditis is even more rare. Cervical blastomycosis, on one occasion masquerading as a thyroid mass, has been reported. Here we report the first case of acute blastomycosis infection of the thyroid documented by biopsy and imaging studies. The patient was a 23-year-old woodcutter with no history or features of overt immunodeficiency. The initial response to Itraconazole therapy was satisfactory.  相似文献   
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