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101.
102.
Small instestinal submucosa (SIS) is an easily produced material that has been used experimentally for tissue engineering. To evaluate the ability of SIS to facilitate bone growth within a long-bone defect, a segment of the radius was surgically removed in adult, female Sprague-Dawley rats. The defect was either left unfilled or implanted with SIS, demineralized cortical bone (DMCB), or ovalbumin. The defect was evaluated radiographically and histologically after 3, 6, 12, and 24 weeks. Tissue remodeling within the defect was evident by week 3 in SIS- and DMCB-treated rats. Filling was characterized initially by infiltration of mononuclear cells and extracellular material in SIS-implanted rats and multifocal remodeling bone particles and cartilage formation in DMCB implanted rats. Cartilage was observed as early as 3 weeks and bone as early as 6 weeks in SIS-implanted rats. Filling of the defect arose from multiple foci in DMCB-implanted rats, but was contiguous with and parallel to the ulnar shaft in SIS-implanted rats, suggesting that defect repair by SIS may be conductive rather than inductive. Rats in which the defect was left unfilled demonstrated slow but progressive filling of the defect, characterized by mononuclear cell infiltrates and fibrous extracellular material. In summary, SIS facilitated rapid filling of a longbone defect. These results suggest that SIS may be useful as a bone repair material.  相似文献   
103.
ABSTRACT

Objectives: Glioblastoma is the most common primary malignant brain tumor in adults, and despite decades of intensive research regarding its pathophysiology and treatment, the prognosis for glioblastoma patients remains poor. While many studies have analyzed various factors that may influence survival outcomes, the focus of this brief review is to discuss the influence that apatient’s race/ethnicity has on survival. This factor has been investigated in large population-based studies and in smaller institutional analyses, but the prognostic utility of this factor has been inconsistent. Discussion of this topic is therefore warranted to better equip providers to counsel and treat patients with glioblastoma, as well as to identify areas of future research.

Methods: A comprehensive literature search is performed to identify studies that reported GBM survival outcomes by race/ethnicity.

Results: Although some discrepancies exist, asignificant survival benefit is associated with the Asian or Pacific Islander (API) race, whereas white patients have the poorest survival and highest incidence. Hispanic patients tend to fare better than white patients but have worse survival than APIs.

Discussion: Further analysis into the differences in survival among different races may lead to an increased understanding of potential molecular and genetic targets, thus guiding future treatment plans for these patients.

Abbreviations: AAAIR: Average Annual Age-Adjusted Incidence Rate; AI/AN: American Indian or Alaska Native; API: Asian or Pacific Islander; CBTRUS: Central Brain Tumor Registry of the United States; CUMC: Columbia University Medical Center; EOR: Extent of Resection; Exc: Excluded; GBM: Glioblastoma; GTR: Gross Total Resection; IDH-1: Isocitrate Dehydrogenase 1; MGMT: O6-Methylguanine DNA Methyltransferase; NCDB: National Cancer Database; OS: Overall Survival; O/U: Other/Unknown; PFS: Progression-Free Survival; SEER: Surveillance, Epidemiology, and End Results; S&W BTR: Scott & White Brain Tumor Registry; UCLA: University of California Los Angeles; UM: University of Miami.  相似文献   
104.
Abstract

Communication partners is a novel aphasia treatment plan whose aim is to restore a sense of purpose, direction, and control to daily life for both patient and caregiver. Treatment involves the participation of a community volunteer who, once paired with an aphasic adult, acts as a liaison in bridging clinical and real-life pursuits. Initially, treatment pairs are taught how to interact freely and effectively. Once comfortable in each other's company these partners embark on activities of the patient's choosing at home or in the community. Results from 10 treated pairs failed to yield significant differences on the Boston Diagnostic Aphasia Exmamination, Communication Abilities in Daily Living, or the Affect Balance Scale. However, all participants, i.e. patients, caregivers, and communication partners, noted statistically significant gains in the aphasic adult's well-being and communication on two investigator-constructed questionnaires. Other informal measures also supported the use of this treatment. The significance of these findings, as well as methodological considerations when undertaking this type of research, are discussed.  相似文献   
105.
106.
Having a relative with an eating disorder (ED) affects the life of family caregivers and may thus affect their quality of life. To study this aspect, 40 caregivers of ED patients filled out a health-related quality of life questionnaire (Short Form-36) and a questionnaire on the impact of the ED on various areas of life domains, and on the relationship with the ED patient and the need for professional support. Quality of life of caregivers was worse than in a normal reference group. Specifically, mental health, vitality and emotional role functioning were reported to be most impaired. ED appeared to affect families’ lives substantially. In response to the ED, caregivers felt anxious, powerless, sad, or desperate. The relationship of the caregiver with the ED patient had also changed. Caregivers were more worried, lost their trust, and reported more conflicts. Seventy five percent welcomed professional support. Caregivers need practical advice, information on ED, and emotional support. Quality of life of caregivers should be addressed in the treatment of ED.  相似文献   
107.
Positron emission tomography (PET) with the high affinity dopamine D2/3 receptor ligand [18F]‐fallypride affords estimates of the binding potential (BPND) in extra‐striatal regions of low receptor abundance, but the sufficient recording time for accurate measurements in striatum has been called into question. We have earlier argued that transient equilibrium measurements are obtained in striatum with [18F]‐fallypride PET recordings of 3 h duration, which may be the practical limit for clinical investigations without interrupted scanning. However, the high extraction fraction of [18F]‐fallypride predicts flow‐dependence of tracer delivery to brain, which may be a source of variance of the apparent BPND in regions of high binding. To test this prediction, we conducted a retrospective analysis of [18F]‐fallypride PET data from a group of 50 healthy volunteers (age 18–58 years [mean ± SD: 32.6 ± 10.6), who had participated in clinical studies without arterial input measurements. We used the initial 120‐s integral (AUC) of the venous confluence (VC) as a surrogate marker for cerebral blood flow (CBF) and tested for correlations between regional estimates of BPND calculated by the simplified reference tissue model (SRTM) and the individual VC‐AUC. The magnitude of BPND in a high binding region (putamen), but not in a low binding region (thalamus) correlated positively with VC‐AUC, suggesting that approximately 9% of the variance in the [18F]‐fallypride BPND in putamen can be attributed to individual differences in this surrogate marker for CBF, a contribution equal in magnitude to the effects of age on BPND in putamen of the present healthy control group. Synapse, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
108.
目的通过观察亚麻子水提液对二肽基肽酶-4(DPP-4)、α-葡萄糖苷酶抑制作用,为该药防治糖尿病提供实验依据。方法①以DPP-4酶、缓冲液、底物建立DPP-4抑制剂的体外筛选体系,对亚麻子水提液进行抑制实验,采用发色底物法测定吸光度(OD),计算DPP-4抑制率及IC50值;②以蔗糖为底物建立α-葡萄糖苷酶活性抑制模型,采用葡萄糖氧化酶法测定亚麻子水提液对α-葡萄糖苷酶的抑制作用,计算其抑制率和IC50值。结果①亚麻子具有轻度DPP-4抑制作用,其IC50值738.20mg/L;②亚麻子具有α-葡萄糖苷酶抑制作用,其IC50值为365.9mg/mL。结论亚麻子水提液可一定程度地抑制DPP-4及α-葡萄糖苷酶活性。  相似文献   
109.
Identification of the signalling cascades that are differentially activated during prostatic tumourigenesis is a crucial step in the search for future molecular targets in this disease. The stress-activated protein kinase (SAPK) signalling cascade culminates in the phosphorylation of the JNK and p38 mitogen-activated protein kinases (MAPKs). Recently, the upstream activators of these proteins, the MAPK kinases (MKKs), have been implicated as inhibitors of tumour progression in a variety of clinical and experimental tumour models. This study evaluates MKK4, MKK6 and MKK7 expression during prostate cancer progression in humans and in the transgenic adenocarcinoma of a mouse prostate (TRAMP) model of prostate tumourigenesis. Benign prostate, prostatic intraepithelial neoplasia (PIN) lesions and tumour tissues were collected from 37 TRAMP mice. Additionally, six tissue microarrays were constructed with tumours from a matched group of 102 men who underwent radical prostatectomy. Tissues from 20 patients with extensive high-grade prostatic intraepithelial neoplasia (HGPIN) were also analysed. For all samples, immunohistochemical staining for MKK4, MKK6 and MKK7 was scored in normal and neoplastic glands. Staining intensities of MKK4, MKK6 and MKK7 were significantly increased in HGPIN and prostate cancer compared to surrounding normal glands in both the TRAMP and human samples (p < 0.0001 for all markers). Increased levels of MKK4 or MKK7 correlated with higher pathological stage at prostatectomy (p = 0.01 and p = 0.04). Using multivariate analysis, there was no association between protein levels and time to biochemical recurrence in the human samples. The up-regulation of MKK4, MKK6 and MKK7 during prostate cancer progression in both TRAMP and human tissues highlights an important role for the SAPK signalling cascade in prostatic neoplasia. The finding that higher MKK4 and MKK7 expression is associated with higher-stage prostatic tumours underscores the dynamic regulation of these proteins during prostatic tumourigenesis.  相似文献   
110.
Gas-to-liquid (GTL) products are synthetic hydrocarbons produced from natural gas using a catalytic process known as the Fischer–Tropsch process. This process yields a synthetic crude oil that consists of saturated hydrocarbons which can subsequently be refined to a range of products analogous to those obtained from petroleum refining. However, in contrast to their petroleum-derived analogs, GTL products are essentially free of unsaturated or aromatic compounds and do not contain any sulfur-, oxygen-, or nitrogen-containing compounds. Under new chemical substance notification requirements, an extensive testing program covering the entire portfolio of GTL products has been undertaken to assess their hazardous properties to human health and environment. The results of these studies have been summarized in a two-part review. Part 1 provides an overview of the mammalian toxicity hazardous properties of the various GTL products. This second part of the review focuses on the aquatic, sediment, terrestrial, and avian toxicity studies which assess the ecotoxicological hazard profile of the GTL products. Many challenges were encountered during these tests relating to dosing, analysis and interpretation of results. These are discussed with the intent to share experiences to help inform and shape future regulatory mandates for testing of poorly soluble complex substances. As was the case with the mammalian toxicology review, there were a few cases where adverse effects were found, but overall the GTL products were found to exert minimal adverse ecotoxicological effects and these were less severe than effects observed with their conventional, petroleum-derived analogs.  相似文献   
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