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71.
72.
Cutaneous leiomyosarcoma typically presents as solitary, well‐circumscribed, firm plaques or nodules. We describe a case of cutaneous leiomyosarcoma clinically presenting as a skin tag on the thigh of a 50‐year‐old male. Histological examination of the lesion revealed a dome‐shaped tumor with interlacing fascicles of smooth muscle with pleomorphism, cellular atypia and multiple mitoses. Malignant tumors may rarely present as a skin tag, and these are most frequently basal cell carcinomas. We are unaware of previously reported leiomyosarcoma clinically presenting as a skin tag. This case suggests that solitary, wide‐based, papilloma‐like lesions or skin tags should be submitted for histologic examination to rule out malignancy.  相似文献   
73.
Cisplatin and carboplatin are effective antineoplastic agents. They are also considered to be potentially highly ototoxic. To date, no long-term follow-up data from well-documented cohorts with substantial numbers of childhood cancer survivors (CCS) with platinum-related hearing loss are available. Therefore, in this study, we studied the reversibility of ototoxicity from discontinuation of treatment onwards in a national cohort of platinum-treated survivors with hearing loss at the end of cancer treatment. Of the 168 CCS with follow-up audiograms, we longitudinally evaluated the course of hearing function in 61 CCS who showed hearing impairment at discontinuation of treatment according to the Münster criteria (>20 dB at ≥4–8 kHz). Survivors were treated with platinum (median total cumulative dose cisplatin: 480 mg/m2 and median total cumulative dose carboplatin: 2520 mg/m2). Median follow-up time was 5.5 years (range: 1.0–28.8 years). The results showed that none of these survivors revealed improvement of hearing function even till 28.8 years after discontinuation of treatment (grade <2b during long-term follow-up). An increase in hearing loss with two or three Münster degrees was observed in five of 61 survivors after 1.6–19.6 years. Overall, this indicates that ototoxicity after platinum treatment may be irreversible and that longitudinal clinical audiological monitoring and care is required in long-term survivors of childhood cancer on a large scale.  相似文献   
74.
75.
Chronic obstructive pulmonary disease (COPD), although primarily a disease of the lungs, is associated with extrapulmonary effects such as muscle weakness and osteoporosis. Fractures owing to osteoporosis cause significant morbidity and mortality, particularly in patients with COPD. To prevent osteoporotic fractures, it is important to diagnose osteoporosis in an early stage and to start anti‐osteoporotic therapy in at‐risk patients. Because routine chest computed tomography (CT) is increasingly used to assess the extent of emphysema and airways disease in patients with COPD, we investigated whether simple attenuation measurement of the thoracic spine on routine chest CT may provide useful information on bone health in patients with COPD. Fifty‐eight patients with moderate to very severe COPD were included in our study. The average attenuation of thoracic vertebrae 4, 7, and 10 on chest CT was correlated with the lowest bone mineral density (BMD) of the hip and lumbar spine (L1 to L4) on dual‐energy X‐ray absorptiometry (DXA) in patients with COPD. The inter‐ and intra‐observer variabilities of the attenuation measurements were low as shown by Bland‐Altman plots. Pearson's correlation coefficient between the average attenuation of the three thoracic vertebrae and the lowest BMD of the hip and lumbar spine was high (r = 0.827, p < 0.001). A receiver‐operating characteristic (ROC) analysis of the area under the curve for osteoporosis was 0.969 (p < 0.001), corresponding to an attenuation threshold of 147 Hounsfield Units (HU). In conclusion, our data demonstrated that bone attenuation measured on routine chest CT correlated strongly with BMD assessed on DXA in patients with COPD. Routine chest CT may provide useful information on bone health in patients with COPD. © 2012 American Society for Bone and Mineral Research.  相似文献   
76.
Stickler syndrome (hereditary arthro-ophthalmopathy) is the commonest inherited cause of retinal detachment and one of the commonest autosomal dominant connective tissue dysplasias. There is clinical and locus heterogeneity with about two thirds of families linked to the gene encoding type II procollagen (COL2A1). Families with Sticklers syndrome type 1 have a characteristic congenital vitreous anomaly and are linked without recombination to markers at the COL2A1 locus. In contrast families with the type 2 variety have a different vitreo- retinal phenotype and are not linked to the COL2A1 gene. Type XI collagen is a quantitatively minor fibrillar collagen related to type V collagen and associated with the more abundant type II collagen fibrils. A mutation in COL11A2, the gene for alpha 2 (XI) procollagen, has recently been found in a family described as having Stickler syndrome, although there was no ocular involvement. Here we show for the first time that a family with the full Type 2 Stickler syndrome including vitreous and retinal abnormalities is linked to the COL11A1 gene and characterise the mutation as a Glycine to Valine substitution at position 97 of the triple helical domain caused by a single base G-- >T mutation. These results are the first to provide confirmation that type XI collagen is an important structural component of human vitreous. They also support previous work suggesting that mutations in the genes encoding collagen XI can give rise to some manifestations of Stickler syndrome, but of these, only mutations in COL11A1 will give the full syndrome including the vitreo-retinal features.   相似文献   
77.

Background

Interventions aimed at behavior change are increasingly being delivered over the Internet. Although research on intervention effectiveness has been widely conducted, their true public health impact as indicated by reach, effectiveness, and use is unclear.

Objective

The aim of this paper is to (1) review the current literature on online prevention aimed at lifestyle behaviors, and (2) identify research gaps regarding reach, effectiveness, and use.

Methods

A systematic search in PubMed revealed relevant literature published between 2005 and 2012 on Internet-delivered behavior change interventions aimed at dietary behaviors, physical activity, alcohol use, smoking, and condom use. Our search yielded 41 eligible reviews, which were analyzed in terms of reach, effectiveness, and use according to the RE-AIM framework.

Results

According to health priorities, interventions are largely targeted at weight-related behaviors, such as physical activity and dietary behavior. Evaluations are predominantly effect-focused and overall effects are small, variable, and not sustainable. Determinants of effectiveness are unclear; effectiveness cannot yet be unambiguously attributed to isolated elements. Actual reach of interventions is undiversified, mostly reaching participants who are female, highly educated, white, and living in high-income countries. One of the most substantial problems in online prevention is the low use of the interventions, a phenomenon seen across all behavior domains.

Conclusions

More research is needed on effective elements instead of effective interventions, with special attention to long-term effectiveness. The reach and use of interventions need more scientific input to increase the public health impact of Internet-delivered interventions.  相似文献   
78.
BACKGROUND: A good blood bank must be able to provide compatible blood units promptly to operating room patients with minimal wastage. A "self- service" by nursing staff blood banking system that is safe, efficient, and well-accepted has been developed. STUDY DESIGN AND METHODS: Specific blood units are no longer assigned to surgical patients who have a negative pretransfusion antibody screen, irrespective of the type of surgery. A computer-generated list of the serial numbers of all group-identical blood units currently in the blood bank inventory is provided for each patient. The units themselves are not labeled with a patient's name. The group O list will be provided for group O patients, the group A list for group A patients, and so forth. Should the patient require transfusion during surgery, the operating room nurses go to the refrigerator, remove any group-identical unit, and check the serial number of the unit against the serial numbers on the patient's list. If the serial number is on that list, the blood bank will accept responsibility for compatibility. The system was implemented in 1995. RESULTS: Since implementation, a total of 2154 patients have undergone operations at this hospital. Thirty-two patients received more than 10 units of red cells each. There were no transfusion errors. The crossmatch-to-transfusion ratio was reduced from 1.67 to 1.12. Turnaround time for supplying additional or urgent units to patients in operating room was shortened from 33 to 2.5 minutes. There was no incidence of a blood unit's serial number not being on the list. Work by nurses and technical staff was reduced by nearly 50 percent. CONCLUSION: The "self-service" (by nursing staff) blood banking system described is safe and efficient. It saves staff time and can be easily set up.  相似文献   
79.
During detailed immunophenotypic analyses of marrow blasts from 336 acute lymphoblastic leukemia (ALL) patients, a very small percentage of cases reactive with B-cell-directed as well as T-cell-directed monoclonal antibodies (MoAbs) were identified. Five ALL cases were biphenotypic since they coexpressed CD2 (Tp50) and CD19 (Bp95) antigens at the single-cell level. The composite immunophenotype of these biphenotypic ALL cases was [TdT+HLA-ABC+CD2+CD3-CD10+CD13-CD14-CD16- CD19+CD20+ ++-CD21-CD33-CD34+Bgp95-C mu- slg-]. Low-molecular-weight B- cell growth factor (LMW-BCGF), recombinant interleukin-2 (rIL-2), and rIL-3 stimulated the proliferative activity of biphenotypic leukemic lymphocyte precursors without inducing differentiation. In the presence of the phorbol ester TPA, leukemic blasts from two cases differentiated along the B precursor pathway to the [CD2-CD10+CD19+CD20+C mu+slg-] pre- B cell stage. Biphenotypic ALL cases did not share a common configuration and gene rearrangement pattern of the immunoglobulin heavy chain genes or T-cell receptor (TCR) genes. Three cases had rearranged C mu genes but germline TCR genes, one case showed rearrangement of both C mu and TCR genes, and the remaining case had rearranged TCR genes but germline C mu genes. All five patients attained prompt remission after standard induction chemotherapy. Three to four years after initial diagnosis, four patients are now off chemotherapy and remain alive in their first remission. One patient relapsed at 3 years, 7 months, but promptly achieved complete remission after reinduction chemotherapy and remains in second remission off chemotherapy greater than 3 years after her reinduction therapy. With two-color immunofluorescence staining techniques and multiparameter flow cytometric analyses, we identified a small population of CD2+CD19+ lymphoid cells in fetal livers (FLs) and fetal bone marrows (FBMs), which may represent the putative normal counterparts of biphenotypic ALL blasts. A CD2+CD19+ normal biphenotypic lymphoid precursor cell line, designated FL 8.2 CD2+, was established from an FL of 8-weeks of gestational age by Epstein-Barr virus (EBV)-induced blastoid transformation. The composite immunophenotype of FL 8.2 CD2+ cell line was [TdT+HLA-ABC+HLA-DR+ CD2+CD5-CD7-CD10+/-CD13-CD19+CD20-CD21+ CD22+CD33-CD34+/-Bgp95-CDw40+C mu-slgD-slgM-]. FL 8.2 CD2+ cells showed germline patterns of immunoglobulin heavy-chain joining region, heavy- chain constant region, kappa light-chain constant region genes, and TCR beta-chain genes. Cross-linking of CD2 as well as CD19 antigens on FL 8.2 CD2+ cells caused an increase of intracellular ionized calcium.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
80.
To study the frontiers between pluripotent stem cells and committed progenitors and to further define the B-cell pathway in adult bone marrow (BM), CD34+ subpopulations and CD34- B-lineage cells were analyzed by multiparameter flow cytometry, studied by light and electron microscopy, and in short-term and long-term cultures (LTC). While the total CD34+ cells represent 4.9% +/- 0.8 of BM mononuclear cells within the lymphoid-blast window, 73.8 +/- 3.5%, 14.4 +/- 1.8% and 8.8 +/- 2.9% of them were CD34+ CD10- CD19-, CD34+ CD10+ CD19+, and CD34+ CD10+ CD19-, respectively. CD34+ CD10+ CD19+ cells represent a smal homogeneous TdT4 c micro-blast population. Although expressing CD38 and high level of HLA-DR antigens, like myeloid committed progenitors, they did not generate LTC, myeloid, and T lymphoid colonies suggesting that the CD34+ CD10+ CD19+ population represents exclusively B lymphoid committed progenitors. By contrast, all myeloid progenitors and LTC-initiating cells were found in the CD34+ CD10- CD19- cell fraction. This fraction appeared more heterogeneous and contained CD38- HLA-DRlow small cells, larger blasts, and promonocyte-like cells exhibiting small peroxidase-positive granules. Interestingly, CD10 was also present on CD34+ CD19- cells. This population mainly coexpressed CD33 and gave rise to macrophagic colonies.  相似文献   
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