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41.
Acute lymphoblastic leukemia (ALL) is the most common childhood cancer and despite the intense combination chemotherapy, cure rates are less than 90%. Several prognostic parameters, including nonneoplastic hematologic cell counts during induction phase, are suggested to predict outcome in ALL. We analyzed 242 ALL patients treated in our center to investigate individual prognostic parameters and the impact of delays on disease outcome. Age at diagnosis, risk groups, extramedullary involvement, t(9;22), prednisone response, bone marrow response at days 15 and 33, day 15 platelet count, day 33 lymphocyte, monocyte, and platelet counts, treatment delay, sepsis, and omission of day 64 cyclophosphamide were valuable predictors of survival in univariate analysis. However only the age, CNS involvement, omission of cyclophosphamide, and total delay during treatment were associated with survival in multivariate analysis. Omission of second cyclophosphamide dose had no impact on survival of standard risk group patients, but adversely affected the long term survival of medium risk group (MRG) patients. The second dose might be given with the first dose on day 36 to MRG patients to prevent delays. Day 15 and 33 platelet counts are promising predictors of survival in low income countries where assessment of minimal residual disease is difficult, but this data needs further consolidation.  相似文献   
42.
Aims/IntroductionDiabetes mellitus is reported as a risk factor for increased coronavirus disease 2019 (COVID‐19) severity and mortality, but there have been few reports from Japan. Associations between diabetes mellitus and COVID‐19 severity and mortality were investigated in a single Japanese hospital.Materials and MethodsPatients aged ≥20 years admitted to Osaka City General Hospital for COVID‐19 treatment between April 2020 and March 2021 were included in this retrospective, observational study. Multivariable logistic regression analysis was carried out to examine whether diabetes mellitus contributes to COVID‐19‐related death and severity.ResultsOf the 262 patients included, 108 (41.2%) required invasive ventilation, and 34 (13.0%) died in hospital. The diabetes group (n = 92) was significantly older, more obese, had longer hospital stays, more severe illness and higher mortality than the non‐diabetes group (n = 170). On multivariable logistic regression analysis, age (odds ratio [OR] 1.054, 95% confidence interval [CI] 1.023–1.086), body mass index (OR 1.111, 95% CI 1.028–1.201), history of diabetes mellitus (OR 2.429, 95% CI 1.152–5.123), neutrophil count (OR 1.222, 95% CI 1.077–1.385), C‐reactive protein (OR 1.096, 95% CI 1.030–1.166) and Krebs von den Lungen‐6 (OR 1.002, 95% CI 1.000–1.003) were predictors for COVID‐19 severity (R 2 = 0.468). Meanwhile, age (OR 1.104, 95% CI 1.037–1.175) and Krebs von den Lungen‐6 (OR 1.003, 95% CI 1.001–1.005) were predictors for COVID‐19‐related death (R 2 = 0.475).ConclusionsDiabetes mellitus was a definite risk factor for COVID‐19 severity in a single Japanese hospital treating moderately‐to‐severely ill patients.  相似文献   
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44.
The present series compares results in our head and neck department from primary and salvage surgery for tumors of the tonsillar region from 1978 to 1985. Of 120 consecutively admitted patients, 70 underwent primary surgery followed by irradiation, and 50 underwent salvage surgery after the failure of primary radiotherapy. Follow-up has been continued for the past 6 years. Musculocutaneous flaps were employed in all patients requiring them after the introduction of this reconstructive technique in 1981. The actuarial survival rate after primary surgery was 58% at 3 years and 46% at 5 years. For salvage surgery the figures were 38% and 24%, respectively. This disappointing survival rate in salvage surgery resulted from a higher postoperative mortality (8% versus 1.4% in primary surgery) and from a higher local failure rate (36% versus 14%). The outcome was invariably unfavorable when tonsillar tumors extended into the base of the tongue.  相似文献   
45.
PurposePatients’ preferences of the type of sample collections for clinical testing are currently unknown. The aims of this study were: (1) to assess patients’ preferences of three types of samples for clinical testing (saliva, urine and blood) both before and after collection and (2) to assess whether prior experiences with collection of saliva impacted patients responses.MethodsAdult outpatients underwent collection of one sample each of saliva, urine and blood. Patients’ perceptions of comfort, convenience and easiness were assessed in pre-collection and post-collection questionnaires.ResultsPost-collection, patients’ endorsement of saliva as being the “most comfortable” and “most convenient” significantly declined (pre vs. post, 61.5% vs. 37.5% and 73.1% vs. 42.3%). However, saliva was still endorsed as the “most convenient” post-collection (compared to urine 33.7% and blood 24.0%).Although not statistically significant, the proportion of patients who changed their response in terms of what sample was “easiest to collect at home” was considerably higher in the group with vs. without prior experience giving saliva (54.6% vs. 32.6%, p = 0.19 Fisher's exact test).ConclusionsOverall, saliva remained as the most highly preferred sample to donate despite a decline in patients’ preferences of saliva donation after sample collection.The results of the study are promising for future widespread patient acceptance of saliva as a diagnostic fluid.  相似文献   
46.
Otitis media with effusion (OME) occurs when fluid collects in the middle-ear space behind the tympanic membrane (TM). As a result of this effusion, sounds can become attenuated by as much as 30–40 dB, causing a conductive hearing loss (CHL). However, the exact mechanical cause of the hearing loss remains unclear. Possible causes can include altered compliance of the TM, inefficient movement of the ossicular chain, decreased compliance of the oval window-stapes footplate complex, or altered input to the oval and round window due to conduction of sound energy through middle-ear fluid. Here, we studied the contribution of TM motion and umbo velocity to a CHL caused by middle-ear effusion. Using the chinchilla as an animal model, umbo velocity (V U) and cochlear microphonic (CM) responses were measured simultaneously using sinusoidal tone pip stimuli (125 Hz–12 kHz) before and after filling the middle ear with different volumes (0.5–2.0 mL) of silicone oil (viscosity, 3.5 Poise). Concurrent increases in CM thresholds and decreases in umbo velocity were noted after the middle ear was filled with 1.0 mL or more of fluid. Across animals, completely filling the middle ear with fluid caused 20–40-dB increases in CM thresholds and 15–35-dB attenuations in umbo velocity. Clinic-standard 226-Hz tympanometry was insensitive to fluid-associated changes in CM thresholds until virtually the entire middle-ear cavity had been filled (approximately >1.5 mL). The changes in umbo velocity, CM thresholds, and tympanometry due to experimentally induced OME suggest CHL arises primarily as a result of impaired TM mobility and TM-coupled umbo motion plus additional mechanisms within the middle ear.  相似文献   
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48.

Purpose

The purpose of this review was to analyze existing literature on the relationship between tooth count and mortality by evaluating the findings in the context of methodological variations. We aimed at addressing the question of whether preserving natural teeth can impact mortality.

Study selection

PubMed, Web of Science and CINAHL databases were systematically searched using various combinations of related and synonymous keywords for “tooth count” and “mortality”. The references of included articles were also evaluated for inclusion. Overall 49 studies found to be eligible were critically evaluated and their key findings were summarized.

Results

Studies were conducted in various continents and differed substantially in regards to their sample size, population, methodology, the definition of the tooth count variable, the confounders as well as the mediators accounted for in the analysis. Follow-up period ranged from 1 to 56 years.

Conclusions

Although high variability in the studies precludes a definite conclusion about the relationship between number of teeth and mortality, the overall finding from this review is that reduced tooth count is associated with higher mortality. However the impact of factors such as smoking, health-care access, baseline co-morbidity and risk profile, dental and periodontal health, the presence of dental prosthesis as well as socio-economic status, in mediating whole or part of the association cannot be overlooked and needs further investigation using more standard methodologies. Any differences in males vs. females, as well as among different age groups, will also need further consideration in the future studies.  相似文献   
49.
The cellular mechanisms involved in the development of silicosis have not been fully elucidated. This study aimed to examine influence of silica-induced lung injury on autophagy. Suspensions of crystalline silica particles were administered transnasally to C57BL/6j mice. Immunohistochemical examination for Fas and p62 protein expression was performed using lung tissue specimens. Two-dimensional and quantitative analysis of silica deposits in the lungs were performed in situ using lung tissue sections by an in-air microparticle induced X-ray emission (in-air micro-PIXE) analysis system, which was based on irrradiation of specimens with a proton ion microbeam. Quantitative analysis showed a significant increase of iron levels on silica particles (assessed as the ratio of Fe relative to Si) on day 56 compared with day 7 (p<0.05). Fas and p62 were expressed by histiocytes in granulomas on day 7, and the expressions persisted for day 56. Fas- and p62-expressing histiocytes were co-localized in granulomas with silica particles that showed an increase of iron levels on silica particles in mouse lungs. Iron complexed with silica induces apoptosis, and may lead to dysregulations of autophagy in histiocytes of granulomas, and these mechanisms may contribute to granuloma development and progression in silicosis.  相似文献   
50.
The clinical features of acute myocardial infarction patients in whom abnormal Q wave disappeared were analyzed. Of 201 patients, 40 (20%) (Group A) showed disappearance of Q wave in serial electrocardiograms. Regional ejection fraction of the infarcted portion improved significantly (from 24 +/- 2 to 34 +/- 4%, p less than 0.001) during chronic phase in Group A, but no such improvement was present in Group B patients who showed no change in the Q wave. Global ejection fraction was greater and percent akinetic segment was smaller in Group A than in Group B at chronic phase. Coronary occlusion occurred more often at segment 7 in Group A; in Group B, occlusion occurred more frequently upstream at segment 6, suggesting Group A had a smaller area of risk. Spontaneous recanalization was more often (57%) and complete occlusion was less frequent in Group A. These indicate that Group A is characterized by a smaller area of risk, smaller infarct size, earlier reperfusion, and greater improvement in wall motion. Twenty-eight patients (70%) of Group A lost Q wave within one month and 12 patients (30%), after 3 months or more. Electrical stunning of the myocardium may be a possible mechanism for the early disappearance of Q waves, and anatomical healing for the late disappearance of Q waves.  相似文献   
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