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1.
Cidofovir is an acyclic nucleoside phosphonate with broad-spectrum activity against DNA viruses, including human papilloma virus (HPV). However, data on the efficacy of cidofovir in an immunosuppressive setting remain contradictory. We report for the first time on the promotion of the healing of recalcitrant warts in a patient with myelodysplastic syndrome with intravenous cidofovir treatment.  相似文献   
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Osteoarthrosis (OA) is often associated with pain and disability, which are relieved after total knee arthroplasty (TKA), but the nature of bone changes associated with OA is controversial. We examined preoperative hip and contralateral knee bone mineral density (BMD) in patients requiring TKA and monitored the BMD changes postoperatively. Sixty-nine patients, scheduled to have TKA for osteoarthrotic knees, had both hips and contralateral knee BMD measured by dual-energy X-ray absorptiometry (DXA) at the time of operation (baseline) and at 1 yr after operation. X-rays of the knee joints were also taken to evaluate the severity of OA. Preoperatively, 27% and 38% of the patients had total hip BMD Z-score more than 1 SD in the operated side and contralateral hips, respectively. In all regions of interest (ROI), the mean baseline BMD of the affected side proximal femur was significantly lower than that of the contralateral side (p < 0.0005-0.019). The severity of OA was not associated with BMD. During 1-yr follow-up, the postoperative knee status and the physical activity of the patients (AKS score) improved. However, neither the hip nor the nonoperated knee BMDs increased. Knee OA is associated with significantly lower BMD values in the affected side compared with the contralateral hip, and these levels remained similar or decreased during a 1-yr follow-up. We conclude that improved mobility after TKA does not improve the effects of preoperative disuse-associated bone loss in the short term.  相似文献   
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In a retrospective population-based study we assessed whether and how self-reported former fractures sustained at the ages of 20–34 are associated with subsequent fractures sustained at the ages of 35–57. The 12,162 women who responded to fracture questions of the baseline postal enquiry (in 1989) of the Kuopio Osteoporosis Study, Finland formed the study population. They reported 589 former and 2092 subsequent fractures. The hazard ratio (HR), with 95% confidence interval (CI), of a subsequent fracture was 1.9 (1.6–2.3) in women with the history of a former fracture compared with women without such a history. A former low-energy wrist fracture was related to subsequent low-energy wrist [HR = 3.7 (2.0–6.8)] and high-energy nonwrist [HR = 2.4 (1.3–4.4)] fractures, whereas former high-energy nonwrist fractures were related only to subsequent high-energy nonwrist [HR = 2.8 (1.9–4.1)] but not to low-energy wrist [HR = 0.7 (0.3–1.8)] fractures. The analysis of bone mineral density (BMD) data of a subsample of premenopausal women who underwent dual x-ray absorptiometry (DXA) during 1989–91 revealed that those with a wrist fracture due to a fall on the same level at the age of 20–34 recorded 6.5% lower spinal (P= 0.140) and 10.5% lower femoral (P= 0.026) BMD than nonfractured women, whereas the corresponding differences for women with a former nonwrist fracture due to high-energy trauma were −1.8% (P= 0.721) and −2.4% (P= 0.616), respectively. Our results suggest that an early premenopausal, low-energy wrist fracture is an indicator of low peak BMD which predisposes to subsequent fractures in general, whereas early high-energy fractures are mainly indicators of other and more specific extraskeletal factors which mainly predispose to same types of subsequent fractures only. Received: 21 February 1996 / Accepted: 24 September 1996  相似文献   
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The receptor tyrosine kinase (RTK) Ret is activated by the formation of a complex consisting of ligands such as glial cell line-derived neurotrophic factor (GDNF) and glycerophosphatidylinositol-anchored coreceptors termed GFRalphas. During activation, Ret translocates into lipid rafts, which is critical for functional responses to GDNF. We found that Ret was rapidly ubiquitinated and degraded in sympathetic neurons when activated with GDNF, but, unlike other RTKs that are trafficked to lysosomes for degradation, Ret was degraded predominantly by the proteasome. After GDNF stimulation, the majority of ubiquitinated Ret was located outside of lipid rafts and Ret was lost predominantly from nonraft membrane domains. Consistent with the predominance of Ret degradation outside of rafts, disruption of lipid rafts in neurons did not alter either the GDNF-dependent ubiquitination or degradation of Ret. GDNF-mediated survival of sympathetic neurons was inhibited by lipid raft depletion, and this inhibitory effect of raft disruption on GDNF-mediated survival was reversed if Ret degradation was blocked via proteasome inhibition. Therefore, lipid rafts sequester Ret away from the degradation machinery located in nonraft membrane domains, such as Cbl family E3 ligases, thereby sustaining Ret signaling.  相似文献   
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OBJECTIVE--To evaluate the predictive value of traditional prognostic factors, nuclear morphometry, and flow cytometric data in invasive breast cancer. DESIGN--Open study. SETTING--One university hospital in Finland. SUBJECTS--248 women with invasive breast cancer followed up for more than 11 years. MAIN OUTCOME MEASURES--Univariate and multivariate analysis of factors thought to indicate prognosis. RESULTS--Diameter of the tumour, lymph node status, S phase fraction. DNA index, the age of the patient, and the SD of nuclear perimeter were significant independent predictors in the whole series in a multivariate analysis. In node negative patients the SED of the nuclear perimeter and diameter of the tumour had independent prognostic value, whereas in node positive patients diameter of the tumour and the S phase fraction were independently related to survival. CONCLUSIONS--Diameter of the tumour is an important prognostic factor in breast carcinomas. Histoquantitative methods are superior to conventional histological techniques for the prediction of outcome in women with breast cancer.  相似文献   
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The biopsy specimens from the primary tumors of 234 women with axillary-lymph-node-positive breast carcinomas (followed up for a mean of 10.9 years) were subjected to interactive morphometric analysis of nine nuclear factors. The proliferative activity of the tumors was estimated by determining two different mitotic indices. Morphometrically determined nuclear factors and mitotic indices showed a significant correlation to the histological grading (p less than 0.0001). Mitotic activity index (MAI; p = 0.018) and volume-corrected mitotic index (M/V index; p = 0.005) accurately predicted the tumor recurrence. Recurrence-free survival was related to the M/V index (p = 0.0003), MAI (p = 0.0024) and tumor size (p = 0.0144). Disease-related survival was determined by the tumor size (p less than 0.0001), M/V index (p = 0.0142) and MAI (p = 0.0492) in that order. On the other hand, the nuclear factors analyzed and the histological grading used had no predictive value (i.e. tumor recurrence, recurrence-free survival or tumor-related survival) in these women. The results indicate that mitotic indices can be successfully applied in place for subjective grading and nuclear morphometry in predicting the disease outcome in patients with axillary-lymph-node-positive breast carcinomas. The mitotic indices provide independent prognostic information in addition to tumor size. The major clinical implications of these results would be to accurately disclose among these women the high-risk patients (i.e. those with high mitotic indices), who might benefit from more agressive adjuvant therapies.  相似文献   
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Background Cosmetic changes are to be expected after radiotherapy for skin tumours. Objectives This study aimed to answer the questions: How frequent are cosmetic changes after soft X‐ray therapy? Do treatment parameters, tumour thickness, localization and size of the irradiated field have a major influence? Were patients irritated by the visual appearance of the irradiated field? Methods In total, 2474 examinations of 1149 irradiated fields were performed. Results Hypopigmentation was found in 64.7% of examinations more than 90 days after therapy, teleangiectases in 43.1%, erythema in 24.8%, and hyperpigmentation in 16.8%. The frequency of hypopigmentation, teleangiectases and hyperpigmentation increased with time from X‐ray exposure; more than 4 years after therapy hypopigmentation was diagnosed in 91.8% and teleangiectases in 82.2% of examinations. Total dose, the time–dose–fractionation factor (TDF), field size and dose per fraction were significantly related to the frequency of cosmetic changes. Incidence rates of cosmetic changes differed by less than 15% if different treatment conditions were compared: thicker vs. thinner tumours, larger vs. smaller fields, higher vs. lower total doses, doses per fraction, and TDF. Frequencies of hypopigmentation, teleangiectases, erythema and hyperpigmentation differed by more than 15% between some localizations on the head. Women reported irritation by the visual appearance of the irradiated field in 12.6% of 1116 interviews, and men in 4.4% of 1284 interviews. Conclusions Cosmetic changes after soft X‐ray therapy are relatively frequent. Treatment parameters, tumour thickness and field size have only a minor influence. Few patients, but more women than men, were irritated by the visual appearance of the irradiated field.  相似文献   
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