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81.
The domain thicknesses and the heterogeneity of the chain dynamics of PS‐b‐PMMA diblock copolymers with different molar masses was studied by 1H and 13C solid‐state NMR. The chain dynamics heterogeneity of different components and inside the interfacial region was investigated by different NMR methods, including 1H residual second van Vleck moments of PS and high‐resolution 13C longitudinal magnetization relaxation. The effect of changes in the morphology on chain dynamics heterogeneity is demonstrated. The interplay between microscopic and mesoscopic properties of diblock copolymer is helpful for a better assessment of their role in the mechanical properties of these systems.

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82.
Cameron lesions are linear erosions located at the neck of a hiatal hernia (HH) in patients with a large HH. The prevalence has been seen in up to 5% of patients with HH who undergo esophagogastroduodenoscopy, and they can be associated with overt gastrointestinal bleeding or anemia. These lesions occur due to vascular compression by the diaphragm in a large sliding HH. Histopathologic changes seen in the biopsy tissue of a Cameron lesion are due to ischemia, but this ischemia is reversible with treatment of HH. The existence of this entity and the histopathologic picture of a Cameron lesion is not well known to pathologists, and therefore, a microscopic picture of a Cameron lesion can be easily confused with ischemic gastritis. Ischemic gastritis is the result of atherosclerosis, usually seen in older people, unrelated to HH, and is not easily reversible. The authors received a gastric biopsy of a hiatal hernia without any associated clinical diagnosis of a Cameron lesion conveyed to the pathologist. This biopsy tissue showed ischemic changes in the gastric mucosa on microscopic examination. Diagnosis of ischemic gastritis was considered but ruled out after the case was discussed with the gastroenterologist. The correct diagnosis was made once the clinical diagnosis of HH with Cameron lesion (ie, a vertical red erosion) was made known to the pathologist. By reporting this case, the authors aim to increase awareness of Cameron lesion among pathologists so that they ask about the presence of a Cameron lesion before making the diagnosis of ischemic gastritis.  相似文献   
83.
Idiopathic pulmonary artery aneurysm rupture was diagnosed in a 79-year-old man who presented with a dry cough. He was considered unlikely to tolerate extensive pulmonary artery reconstruction or lung resection; hence, he was salvaged by timely ligation of the distal pulmonary artery at the origin of the aneurysm.  相似文献   
84.
85.
There is an increase in older-adult renal transplant recipients in United States. The objective of this study was to assess the association between physical function (PF) and patient survival in renal transplant recipients who are aged 65 years or older. Using United Network for Organ Sharing (UNOS) data from 2007 to 2016, renal transplant recipients aged 65 years or older were included. Multivariable Cox regression was used to assess associations between survival and functional status adjusted for age, sex, race, donor quality, diabetes, and dialysis vintage. The study identified 26,721 patients. Patient survival was significantly higher in recipients who needed no assistance and lowest in patients in need of total assistance (P < .0001). In deceased donor (DD) transplants, the relative risk for mortality was 2.06 (1.74-2.43) for total assistance and 1.17 (1.08-1.28) for moderate assistance compared to no assistance (P < .0001). In living donor (LD) transplants, the relative risk of mortality was 1.38 (0.78-2.42) for patients needing total assistance and 1.37 (1.14-1.65) for patients needing moderate assistance compared to patients who did not need assistance (0.003). PF is an independent predictor of post-transplant mortality. Assessment of older potential renal transplant recipients should include assessment and standardization of functional status to counsel about post-transplant survival.  相似文献   
86.
Eustachian valve endocarditis caused by Actinomyces species is extremely rare. A literature review revealed only one reported case—caused by Actinomyces israelii in an intravenous drug abuser.Our patient, a 30-year-old woman who at first appeared to be in good health, presented with fever, a large mobile mass on the eustachian valve, and extensive intra-abdominal and pelvic masses that looked malignant. Histopathologic examination of tissue found in association with an intrauterine contraceptive device revealed filamentous, branching microorganisms consistent with Actinomyces turicensis. This patient was treated successfully with antibiotic agents.In addition to presenting a new case of a rare condition, we discuss cardiac actinomycotic infections in general and eustachian valve endocarditis in particular: its predisposing factors, clinical course, sequelae, and our approaches to its management.  相似文献   
87.
A case-control association study was conducted in Caucasian patients with schizophrenia (DSM-III-R, n = 42) and unaffected controls (n = 47) matched for ethnicity and area of residence. Serum interleukin-2 receptor (IL-2R) concentrations, as well as a dinucleotide repeat polymorphism in the IL-2Rβ chain gene, were examined in both groups. No significant differences in IL-2R concentrations or in the distribution of the polymorphism were noted. This study does not support an association between schizophrenia and the IL-2Rβ gene locus, contrary to the suggestive evidence from linkage analysis in multicase families. © 1995 Wiley-Liss, Inc.  相似文献   
88.
Plasma total transcobalamin (TC) I levels were measured in 434 healthy volunteers by radioimmunoassay (RIA). The results were analyzed for demographic patterns and were compared with lactoferrin, cobalamin, homocysteine, and chemistry panel results. Plasma TC I was higher in blacks than in other ethnic/racial groups and higher in women than in men. TC I levels did not correlate with lactoferrin levels. Lactoferrin showed significant ethnic differences also, but, unlike TC I, its levels were highest in whites. TC I levels correlated with cobalamin but not homocysteine levels. Neither TC I nor lactoferrin correlated with chemistry panel results, including creatinine, total protein, albumin, lactate dehydrogenase, and alkaline phosphatase levels. The demonstration with an RIA that directly measures total TC I that plasma levels are significantly higher in blacks than in other groups may explain the well-known higher cobalamin levels in blacks. Surprisingly, plasma lactoferrin, which has the same cellular sources as TC I, does not correlate with plasma TC I levels and shows dissimilar demographic patterns; lactoferrin levels are highest in whites. These findings suggest that regulation and/or secretion of these 2 proteins differ even though their localization and expression patterns in myeloid precursors are similar.  相似文献   
89.
OBJECTIVE: To evaluate the impact of risperidone on seclusion and restraint in patients at a state psychiatric facility, shortly after risperidone's release. METHODS: Patients who were in the hospital for at least 3 months prior to receiving risperidone and subsequently received risperidone for at least 3 months formed the cohort. A mirror-image design was used with duration to a maximum of 1 year before and 1 year after initiation of risperidone. The hospital population that did not receive either risperidone or clozapine during the same time period was used for comparison of trends of seclusion and restraint. RESULTS: Seventy-four patients (most with schizophrenia) met the inclusion criteria of the risperidone group. There were statistically significant decreases in the number of seclusion hours (2.2 [SD 5.5] to 0.26 [SD 0.06]) and of events (0.23 [SD 0.59] to 0.05 [SD 0.14]) per person per month during risperidone treatment, compared with the prerisperidone treatment period (P = 0.01). The comparison group also evidenced decreases on these measures during the same time period, but the risperidone-treated cohort achieved a proportionally greater reduction. There were similar trends toward reduction in the restraint measures during risperidone treatment compared with prerisperidone, but these did not achieve statistical significance. The comparison group also showed slightly decreased use of restraints over the study period. CONCLUSIONS: Risperidone appears to have had a positive impact on seclusion in this state-hospital psychiatric population. These data support the positive impact of risperidone on violence found in other studies. Violence and aggression are major factors that affect morale among psychiatric patients and staff. So, any benefit in this regard as a result of antipsychotic drug treatment is salutary for patients, families, and health care providers.  相似文献   
90.
Progressive multifocal leukoencephalopathy (PML) is a well recognized demyelinating neurological disorder caused by JC virus. Idiopathic CD4(+) lymphocytopenia (ICL) is a syndrome first described by the Centers for Disease Control and Prevention as a CD4(+) count <300 cells/mm(3) or a CD4(+) count that is <20% of the total T cell count on 2 occasions, with no evidence of human immunodeficiency virus (HIV) infection on testing, and absence of any defined immunodeficiency or therapy that depresses the levels of CD4(+) T cells. To the best of our knowledge, this is the third reported case of PML and ICL, and also the first reported case of the use of cidofovir to treat PML in a patient not infected with human immunodeficiency virus.  相似文献   
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