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991.
Samples of cortical bone, derived from human femur, have been studied using terahertz time-domain transmission spectroscopy. The relationship between the broadband THz parameters and the previously acquired values of Young's modulus and x-ray attenuation (CT number), and the density of each bone sample, is investigated. The only significant correlation is that between THz transmission and sample density, suggesting that the potential use of THz radiation as a non-invasive probe of bone quality is limited. The spectra of absorption coefficient and refractive index are plotted over the frequency range 0.1-1.25 THz. There is evidence that the sample hydration state is a factor in the resultant THz parameters.  相似文献   
992.
The enteric nervous system is formed by neural crest cells that migrate, proliferate, and differentiate into neurons and glia distributed in ganglia along the gastrointestinal tract. In the developing embryo some enteric crest cells cease their caudal movements, whereas others continue to migrate. Subsequently, the enteric neurons form a reticular network of ganglia interconnected by axonal projections. We studied the developing avian gut to characterize the pattern of migration of the crest cells, and the relationship between migration and differentiation. Crest cells at the leading edge of the migratory front appear as strands of cells; isolated individual crest cells are rarely seen. In the foregut and midgut, these strands are located immediately beneath the serosa. In contrast, crest cells entering the colon appear first in the deeper submucosal mesenchyme and later beneath the serosa. As the neural crest wavefront passes caudally, the crest cell cords become highly branched, forming a reticular lattice that presages the mature organization of the enteric nervous system. Neurons and glia first appear within the strands at the advancing wavefront. Later neurons are consistently located at the nodes where branches of the lattice intersect. In the most rostral foregut and in the colon, some neurons initially appear in close association with extrinsic nerve fibers from the vagus and Remak's nerve, respectively. We conclude that crest cells colonize the gut as chains of cells and that, within these chains, both neurons and glia appear close to the wavefront.  相似文献   
993.
There is good evidence to suggest that depression is highly correlated with perceptions of low rank and subordinate status (i.e. feeling inferior, low-self esteem, feeling that others look down on the self, and submissive behaviour). However, it is possible for people to feel inferior and anxious, and behave submissively but not necessarily be depressed. More recently two other processes, defeat and entrapment, have attracted attention as possible processes linked specifically to depression and anhedonia. This research explored the relationship of these variables (social rank variables and defeat and entrapment) to two measures of hedonic tone (low positive affectivity and anhedonia) and anxiety in both a clinical and student population. All variables were strongly associated with lowered hedonic tone and anxiety. However, partial correlations, and a structural equation model fitted to the data from combined groups, suggests that perceptions of defeat play a specifically important role in anhedonia as measured by low positive affect. Framed within an evolutionary model the data suggest that the mechanisms which evolved to help animals accommodate and respond to defeats may have important regulatory effects over positive affect, reducing exploration of and engagement with the environment.  相似文献   
994.
We report four patients with idiopathic hydrops fetalis (IHF), two being affected sibs; the latter represent the first reported familial occurrence. A review identified 45 additional cases that seem to represent 1/3 to 2/3 of all cases of hydrops fetalis of nonimmunologic origin (NIHF). Our patients and the other adequately documented cases permit delineation of “idiopathic” fetal hydrops; ie, that form of the condition which is not associated with any detectable fetal or maternal disorders. These fetuses are usually premature, often the product of a gestation complicated by pre-eclampsia, occasional maternal anemia, and most often polyhydramnios. The fetuses have striking edema of most tissues with effusions into serous cavities, but no other specific anatomic abnormalities. They are often hypoproteinemic, but not anemic and do not manifest signs of accelerated hematopoiesis. Results of fetal and maternal immunohematological examination are normal. Fetal mortality rates approach 100% but recent data suggest that salvage rates can be significantly improved with early diagnosis. This requires accurate diagnosis and all factors and conditions known to be associated with other types of NIHF should be excluded. A relationship between fetal hypoalbuminemia and IHF may exist and needs further investigation. IHF is sporadic in most instances; however, recessive inheritance may be indicated by occurrence in two sibs. IHF represents a distinct, frequently unrecognized and relatively common entity in need of further study and increased recognition.  相似文献   
995.
Introduction: Active ulcerative colitis is associated with significant morbidity and impairment to quality of life. Adalimumab is a welcome addition to the therapeutic armamentarium for clinicians treating patients with moderate-severe ulcerative colitis refractory to conventional therapies, an indication with few prior treatment options. It offers the convenience of self-injection and is most appropriate for outpatients with moderate disease activity.

Areas covered: This review briefly summarizes data from well-designed clinical trials and observational real-life studies that demonstrate the safety and efficacy of adalimumab in UC. Particular attention is paid to newer studies, including those with objective treatment endpoints and pharmacokinetic outcomes that incorporate a treat to target approach in inflammatory bowel disease.

Expert opinion: Adalimumab is effective for the induction and maintenance of remission in patients with moderate-severe ulcerative colitis refractory to conventional therapies. At currently approved doses, it is most suitable for use in outpatients with moderate disease activity; higher doses may be required for patients with more severe disease. The convenience of self-injection will make it popular for remote patients and it may be an appropriate option in patients in whom monotherapy, rather than combination therapy with an immunomodulator, is preferred.  相似文献   

996.
997.
Recovery housing is a service delivery modality that simultaneously addresses the social support and housing needs of those in recovery from substance use disorders. This article describes a group of recovery homes in Texas (N = 10) representing a lesser-studied type of recovery housing, one which explicitly bridges treatment and peer support by providing a variety of recovery support services. All residents meet with a recovery coach, undergo regular drug screening, and have access to intensive outpatient treatment—a program that was developed specifically to support the needs of residents in the homes. Unlike the Oxford HouseTM model and California sober living houses, which are primarily financed through resident fees, these homes are supported through a mix of resident fees as well as private and public insurance. While adhering to some aspects of the social model of recovery, none of these homes would meet criteria to be considered a true social model program, largely because residents have a limited role in the governance of the homes. Residences like the ones in this study are not well-represented in the literature and more research is needed.  相似文献   
998.
Background: Having a stable and safe place to live is integral to recovery from addiction. Recovery residences represent an important component in the substance use continuum of care, but research on them has been limited to certain types of recovery residences and has yet to examine quality of life among those who live in them. Methods: This study presents data on the characteristics of residents (N = 104) living in a stratified random sample of recovery homes in Philadelphia (N = 13) as well as data from a random subsample of residents (N = 27) who participated in 3-month follow-up interviews. Results: Residents in these homes reported deficits in a variety of aspects of their lives critical to helping them initiate and sustain their recovery; many (20%) reported living in a shelter or on the streets prior to moving in, 37% had less than a high school education, and only 26% reported currently working for pay. Although the majority of residents rated their quality of life as good or very good (74%), average physical health, social relationship, and environment domain scores measured by the World Health Organization Quality of Life (WHOQOL)-Bref were generally lower than scores found among community samples. At follow-up, all residents were housed and rates of substance use (7%), criminal justice involvement (0%), and employment (44%) in the past 30 days were encouraging. Quality of life domain scores were unchanged, with the exception of psychological health, which decreased. Conclusions: These findings highlight the complex needs of residents living in Philadelphia recovery homes and the role that these homes play in maintaining residents in their early recovery. Studies with larger samples of residents followed up over longer periods of time are needed to assess the role that these homes may play in promoting long-term recovery and improving the well-being of the vulnerable population of individuals who live in them.  相似文献   
999.
1000.
BACKGROUND: Identification of Crohn's disease (CD)-associated genetic variants is key to understanding pathogenic pathways underlying disease susceptibility. Recent reports of an association between TNFSF15 variants and CD have been modestly replicated in European populations, suggesting heterogeneity at this locus with stronger CD association in Japanese than European populations. METHODS: We investigated the association between variants in TNFSF15 and CD in 756 CD patients and 636 controls. Disease subphenotype associations were also investigated. RESULTS: TNFSF15 single nucleotide polymorphism (SNP) variants were associated with CD in our panel with peak odds ratio (OR) 1.2 (95% confidence interval [CI] 1.01-1.41) P = 0.033. The presence of a risk haplotype was replicated for the first time in a European population (frequency 67% in cases and 61% in controls) OR = 1.44 (95% CI 1.23-1.68) P = 0.00012. This result mirrors the UK panel in the index study (Yamazaki et al [2005] Hum Mol Genet 14:3499-3506) but is less significant than that reported in Japanese populations. There was no evidence of association with any individual CD subphenotype. CONCLUSIONS: Variants in TNFSF15 contribute to overall CD susceptibility in European populations, although to a lesser extent than that seen in the Japanese. Further studies to define the precise disease-causing variants as well as targeted functional studies are now required in human CD as TNFSF15 is a potential target for biological therapies.  相似文献   
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