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排序方式: 共有6319条查询结果,搜索用时 36 毫秒
1.
《Saudi Dental Journal》2022,34(6):445-448
PurposeThe article subject relevance is conditioned by poor knowledge of the aetiology and pathogenesis of inflammatory diseases in this area. The purpose of this study was to identify the most rational approach to solving the issues of improving methods for treating arthritis and arthrosis.MethodsThe leading approach was the combination of the analysis results concerning the clinical examination of dental patients of various age groups with the logical construction of conclusions drawn from the research results. The paper presented the clinical examination data of patients with TMJ pathologies of various age groups and described the methods of their treatment.ResultsThe results include the main effective methods identification for the diagnostics and treatment of inflammatory diseases in the temporomandibular joint and the main prospects for improving these methods in the future, with the aim of a general expansion of ideas regarding the possibilities of diagnostics and treatment of such diseases.ConclusionThe study value lies in the possibility of using its results in practical dentistry to bring practical improvements to the currently available methods for diagnostics and treatment of inflammatory TMJ diseases. 相似文献
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Chrystalle Katte Carreon Annachiara Benini Christopher Baird David Hoganson Michele Borisuk Sitaram Emani Sophie Hofferberth Robert F. Padera Stephen P. Sanders 《The Journal of thoracic and cardiovascular surgery》2019,157(1):342-350.e3
Objectives
Although valved venous homografts (VVHs) are used for establishing right ventricle-to-pulmonary artery continuity in some complex heart defects, the tissue changes that occur in situ have not been described. We review the gross and microscopic changes observed in explanted VVH conduits and their effects on functionality.Methods
In total, 20 explanted VVH conduits were evaluated for valve integrity, presence of thrombus, and stenosis. Hematoxylin and eosin– and trichrome-stained sections were reviewed for neointima formation, wall remodeling, inflammation, and calcification. Regurgitation and narrowing were assessed on pre-explant echocardiogram, and angiographic video clips were correlated with tissue findings. The source of the proliferating cells within the conduits was investigated by fluorescent in situ hybridization.Results
Thirteen male and 7 female infants underwent VVH implantation either as part of a composite Sano shunt (65%) or to establish right ventricle-to-pulmonary artery continuity in biventricular hearts (35%). The median duration of conduits in situ was 140 days (range: 98-340 days). Conduits were predominantly explanted for staged conversion to bidirectional Glenn (60%) and conduit upsizing (20%). The valves remained intact and functional in 75% of cases. Occlusive thrombosis was absent in all. Wall thickening due to neointima formation and wall remodeling was uniformly present and appeared to be driven by smooth muscle actin–expressing cells, which by fluorescent in situ hybridization are predominantly of recipient origin. Minimal calcification and mild adventitial chronic inflammation were present.Conclusions
Vein wall thickening is a uniform finding and can cause stenosis. The valves remain functional in most, and vein walls undergo remodeling with only minimal inflammation and calcification. 相似文献3.
Sebastian Linde 《Health economics》2019,28(12):1435-1448
This study explores the forces that drive the formation of physician patient sharing networks. In particular, I examine the degree to which hospital affiliation drives physicians' sharing of Medicare patients. Using a revealed preference framework where observed network links are taken to be pairwise stable, I estimate the physicians' pair‐specific values using a tetrad maximum score estimator that is robust to the presence of unobserved physician specific characteristics. I also control for a number of potentially confounding patient sharing channels, such as (a) common physician group or hospital system affiliation, (b) physician homophily, (c) knowledge complementarity, (d) patient side considerations related to both geographic proximity and insurance network participation, and (e) spillover from other collaborations. Focusing on the Chicago hospital referral region, I find that shared hospital affiliation accounts for 36.5% of the average pair‐specific utility from a link. Implications for reducing care fragmentation are discussed. 相似文献
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Lino Möhrmann Martina K. Zowada Hendrik Strakerjahn Christine Siegl Annette Kopp-Schneider Damir Krunic Dirk Strunk Martin Schneider Mark Kriegsmann Katharina Kriegsmann Friederike Herbst Claudia R. Ball Hanno Glimm Sebastian M. Dieter 《International journal of cancer. Journal international du cancer》2020,147(2):519-531
Disseminated tumor cells (dTCs) can frequently be detected in the bone marrow (BM) of colorectal cancer (CRC) patients, raising the possibility that the BM serves as a reservoir for metastatic tumor cells. Identification of dTCs in BM aspirates harbors the potential of assessing therapeutic outcome and directing therapy intensity with limited risk and effort. Still, the functional and prognostic relevance of dTCs is not fully established. We have previously shown that CRC cell clones can be traced to the BM of mice carrying patient-derived xenografts. However, cellular interactions, proliferative state and tumorigenicity of dTCs remain largely unknown. Here, we applied a coculture system modeling the microvascular niche and used immunofluorescence imaging of the murine BM to show that primary CRC cells migrate toward endothelial tubes. dTCs in the BM were rare, but detectable in mice with xenografts from most patient samples (8/10) predominantly at perivascular sites. Comparable to primary tumors, a substantial fraction of proliferating dTCs was detected in the BM. However, most dTCs were found as isolated cells, indicating that dividing dTCs rather separate than aggregate to metastatic clones—a phenomenon frequently observed in the microvascular niche model. Clonal tracking identified subsets of self-renewing tumor-initiating cells in the BM that formed tumors out of BM transplants, including one subset that did not drive primary tumor growth. Our results indicate an important role of the perivascular BM niche for CRC cell dissemination and show that dTCs can be a potential source for tumor relapse and tumor heterogeneity. 相似文献
7.
Periosteal new bone formation (PNBF) is a common finding in a large spectrum of diseases. In clinical practice, the morphology and location of periosteal lesions are frequently used to assist in the differential diagnosis of distinct bone conditions. Less commonly reported is the presence of PNBF on the ribs. This contrasts with the data retrieved from the study of skeletonized human remains that shows a high frequency of cases and a strong, albeit not specific, association between periosteal rib lesions and pulmonary conditions (e.g. tuberculosis). Despite that, an overall disagreement regarding the specificity and non‐specificity of periosteal reactions exists in the study of dry bone remains. The insufficient number of clinical models exploring the morphology and the pathophysiology of PNBF's and the lack of systematic studies of pathological samples with a known diagnosis are claimed as major reasons for the disagreements. This study aimed to describe and compare the macroscopic and the histomorphologic appearance of periosteal rib lesions and to discuss their usefulness as diagnostic indicators. To pursue this goal, an assemblage of 13 rib samples (males = 11, females = 2, mean age‐at‐death = 36.6 years old) was collected from the Luis Lopes Skeletal Collection (Museu Nacional de História Natural e da Ciência, Universidade de Lisboa, Portugal). The assemblage belongs to individuals who died from pulmonary‐TB (group 1), non‐TB pulmonary infections (group 2) and other conditions (group 3). Prior to sample preparation, the ribs were visually inspected and the PNBF described according to its thickness, the degree of cortical integration and the type of new bone formed (e.g. woven, lamellar or both). After sampling, each bone sample was prepared for histological analysis under plane and polarized light microscopy. Macroscopically, the results showed no differences in the new bone composition between cause‐of‐death groups. Only slight differences in the degree of cortical integration, which was most frequently classified as mild to high in the pulmonary‐TB group, were observed. Histologically, no distinguishing features were identified by pathological group. However, new bone microarchitectures were observed compatible with (1) acute, fast‐growing processes (e.g. spiculated reactions), (2) long‐standing processes with a rapid bone formation (e.g. appositional layering of bone) and/or (3) chronic, slow‐growing processes (e.g. layers of compact lamellae). To some extent, these distinct rates of disease progression resonate with the cause‐of‐death listed for some individuals. Despite the small sample size, the results of this investigation are in agreement with previous studies, according to which the macroscopic and histological appearance of periosteal formations are not specific for a particular pathological conditions. Nevertheless, the results support the conclusion that the morphology of periosteal lesions is a good biological indicator for inferring the rate of progression and duration of pathological processes. This study provides important reference data regarding the histomorphology of periosteal lesions that can be used for comparative purposes, as well as to narrow down the differential diagnosis in unidentified skeletal remains. 相似文献
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9.
Francisco Fernández-Klett Josef Priller 《Journal of cerebral blood flow and metabolism》2015,35(6):883-887
Pericytes are mural cells with contractile properties. Here, we provide evidence that microvascular pericytes modulate cerebral blood flow in response to neuronal activity (‘functional hyperemia''). Besides their role in neurovascular coupling, pericytes are responsive to brain damage. Cerebral ischemia is associated with constrictions and death of capillary pericytes, followed by fibrotic reorganization of the ischemic tissue. The data suggest that precapillary arterioles and capillaries are major sites of hemodynamic regulation in the brain. 相似文献
10.
This study examines the role of food and foodways in identity maintenance and formation for Latino individuals in Ithaca, New York. Preliminary results indicate that food provides a physical link that connects individuals to their heritage culture and local communities. Despite variability in the importance that immigrants attribute to food, it remains one of the most resilient tools that informants identified as central to identity formation and maintenance. Food can therefore be a useful tool for examining the degree to which immigrants are maintaining their cultural identity and connectedness with their community. 相似文献