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71.
72.
CD8 T cells play critical roles in controlling intracellular pathogensand tumors. To accomplish this the small number of antigen-inexperienced naive CD8 T cells that are capable of recognizing the antigen of interest must first become primed. These initial activaion events occur while the responding T cells are sequestered within lymph nodes, but many of the cells subsequently egress into the periphery and migrate into other organs where they can fulfill their principle mission of identifying and eliminating infected or malignant target cells.  相似文献   
73.
Breakpoint changes may impact cephalosporin susceptibility rates in uncomplicated urinary tract infections (uUTIs). Applying the ≤16-mg/L breakpoint to urine cultures from adult women in an academic health system resulted in cefazolin being the most active uUTI antimicrobial, with 86.9% susceptibility, compared to levofloxacin (80%), nitrofurantoin (76.5%), and sulfamethoxazole-trimethoprim (72.6%).  相似文献   
74.
Primary cutaneous gamma‐delta (γδ) T‐cell lymphoma is an extremely rare and aggressive variant of cutaneous lymphoma. Central nervous system (CNS) involvement, a rare finding, and hemophagocytic syndrome are two complications that are commonly fatal. We describe a 58‐year‐old patient presenting with skin plaque who subsequently developed subcutaneous nodules diagnosed as cutaneous T‐cell lymphoma (CTCL), clinically resembling ‘mycosis fungoides’. The patient was treated with repeat topical radiation therapies but had frequent relapsed disease. Approximately 4.5 years after, the patient presented with third and sixth cranial nerve palsies and was found to have CNS involvement by lymphoma per positron emission tomography—computed tomography (PET/CT) and a biopsy of foramen magnum. Phenotypically, the tumor cells were CD3(+)/CD4(?)/CD8(?)/CD7(+)/CD5(?)/CD30(?)/TCRαβ(?)/TCRγδ(+). Despite aggressive strategies taken, the patient expired 3 months after the diagnosis of the CNS lesion. A retrospective investigation proved the original CTCL to be γδ T‐cell in origin, confirming an indolent cutaneous γδ T‐cell lymphoma with eventual CNS manifestation. We present this case to draw attention to the entity, which can occasionally present with misleading histopathologic and clinical features. In addition, we provide a review of the literature to summarize clinical and pathologic features of the reported similar cases.  相似文献   
75.

Objectives

There is growing evidence that urine cadmium is a temporally stable biomarker indicative of long-term cadmium exposure; however questions remain with regard to generalizability to older persons, the impact of changes in smoking behavior, and the degree of temporal stability when repeat sample collection spans years instead of weeks or months.

Methods

Using archived samples from cohorts of older men (Osteoporotic Fractures in Men (MrOS-US)) and women (Study of Osteoporotic Fractures (SOF)) (mean age?=?80?at study visit 2), we analyzed two morning urine samples each from 39 men and 18 women with a diverse self-reported smoking history. For MrOS, samples were collected approximately 6 years apart, and 4 years apart for SOF. Intra-class correlations were computed to assess temporal stability, and adjusted for age and body mass index.

Results

The median creatinine-adjusted urinary cadmium levels (0.39?μg/g for men, 0.89?μg/g for women) were similar to levels expected for these age/sex groups in the US according to the National Health and Nutrition Examination Survey. The overall intra-class correlation was high (ICC?=?0.85; 95% CI: 0.76–0.91) and similar between cohorts (MrOS: ICC?=?0.74; 95% CI: 0.58–0.86; SOF: ICC?=?0.81; 95% CI: 0.59–0.93), but slightly lower among those who stopped smoking between visits of sample collection (ICC?=?0.64; 95% CI: 0.31–0.87) or among former smokers who quit prior to the first sample collection (ICC?=?0.68; 95% CI: 0.25–0.93).

Conclusions

We report good-to-excellent reproducibility of urine cadmium using morning urine samples collected 4–6 years apart from older men and women, but slightly lower correlations among those with a history of smoking. Single measures of urine cadmium are a reliable biomarker in older men and women.  相似文献   
76.
This multicenter study analyzed Nocardia spp., including extraction, spectral acquisition, Bruker matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) identification, and score interpretation, using three Nocardia libraries, the Bruker, National Institutes of Health (NIH), and The Ohio State University (OSU) libraries, and compared the results obtained by each center. A standardized study protocol, 150 Nocardia isolates, and NIH and OSU Nocardia MALDI-TOF MS libraries were distributed to three centers. Following standardized culture, extraction, and MALDI-TOF MS analysis, isolates were identified using score cutoffs of ≥2.0 for species/species complex-level identification and ≥1.8 for genus-level identification. Isolates yielding a score of <2.0 underwent a single repeat extraction and analysis. The overall score range for all centers was 1.3 to 2.7 (average, 2.2 ± 0.3), with common species generally producing higher average scores than less common ones. Score categorization and isolate identification demonstrated 86% agreement between centers; 118 of 150 isolates were correctly identified to the species/species complex level by all centers. Nine strains (6.0%) were not identified by any center, and six (4.0%) of these were uncommon species with limited library representation. A categorical score discrepancy among centers occurred for 21 isolates (14.0%). There was an overall benefit of 21.2% from repeat extraction of low-scoring isolates and a center-dependent benefit for duplicate spotting (range, 2 to 8.7%). Finally, supplementation of the Bruker Nocardia MALDI-TOF MS library with both the OSU and NIH libraries increased the genus-level and species-level identification by 18.2% and 36.9%, respectively. Overall, this study demonstrates the ability of diverse clinical microbiology laboratories to utilize MALDI-TOF MS for the rapid identification of clinically relevant Nocardia spp. and to implement MALDI-TOF MS libraries developed by single laboratories across institutions.  相似文献   
77.
Vulvodynia, like many sexual problems, has evolved from being conceptualized as a psychological problem through a period when it became viewed by the medical world as a physical problem, to one having a combination of psychological and physical factors. These are reviewed and presented in an integrated manner, allowing the reader to consider possible treatment modalities for this complex and often highly disabling condition.  相似文献   
78.

Dyspareunia, caused by vulvodynia, has, like other sexual problems, evolved from being conceptualized as a psychological problem through a period when it became viewed by the medical world as a physical problem. It is now seen as being a combination of psychological and physical factors. However, no research to our knowledge has explored in depth the level of sexual and relationship difficulties of this population. This investigation involved 172 women (85 suffering with vulvodynia and 87 women in a control group with general dermatology conditions) to establish the prevalence of relationship and sexual difficulties, using validated questionnaires, a newly devised symptom checklist and a structured interview. The results demonstrated increased levels of sexual and relationship difficulties within the vulvodynia group that need further exploration.  相似文献   
79.
80.
The glenohumeral joint is inherently unstable because the large humeral head articulates with the small shadow glenoid fossa. Traumatic anterior dislocation of the shoulder is a relatively common athletic injury, and the high frequency of recurrent instability in young athletes after shoulder dislocation is discouraging to both the patient and the treating physician. Management of primary traumatic shoulder dislocation remains controversial. Traditionally, treatment involves initial immobilisation for 4–6 weeks, followed by functional rehabilitation. However, in view of the high recurrence rates associated with this traditional approach, there has been an escalating interest in determining whether immediate surgical intervention can lower the rate of recurrent shoulder dislocation, improving the patient’s quality of life. This review article aims to provide an overview of the nature and pathogenesis of first-time primary anterior shoulder dislocations, the widely accepted management modalities, and the efficacy of primary surgical intervention in first-time primary anterior shoulder dislocations.  相似文献   
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