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141.
142.
This study examines interpopulation variations in the facial skeleton of 10 modern human populations and places these in an ontogenetic perspective. It aims to establish the extent to which the distinctive features of adult representatives of these populations are present in the early post natal period and to what extent population differences in ontogenetic scaling and allometric trajectories contribute to distinct facial forms. The analyses utilize configurations of facial landmarks and are carried out using geometric morphometric methods. The results of this study show that modern human populations can be distinguished based on facial shape alone, irrespective of age or sex, indicating the early presence of differences. Additionally, some populations have statistically distinct facial ontogenetic trajectories that lead to the development of further differences later in ontogeny. We conclude that population-specific facial morphologies develop principally through distinctions in facial shape probably already present at birth and further accentuated and modified to variable degrees during growth. These findings raise interesting questions regarding the plasticity of facial growth patterns in modern humans. Further, they have important implications in relation to the study of growth in the face of fossil hominins and in relation to the possibility of developing effective discriminant functions for the identification of population affinities of immature facial skeletal material. Such tools would be of value in archaeological, forensic and anthropological applications. The findings of this study underline the need to examine more deeply, and in more detail, the ontogenetic basis of other causes of craniometric variation, such as sexual dimorphism and hominin species differentiation.  相似文献   
143.
In this study we developed and evaluated a new PCR-based typing assay, directed to the VD2 region of the omp1 gene, for the detection and typing of urogenital Chlamydia trachomatis infections. A nested VD2 PCR-reverse line blot (RLB) assay was developed for the typing of nine different urogenital serovars of C. trachomatis. The assay developed was tested with reference strains of C. trachomatis serovars and cervical scrapes of 86 Colombian women previously found to be positive for C. trachomatis by using plasmid PCR. Two sets of primers directed to the VD2 region of the omp1 gene of C. trachomatis were designed, and fragments of 220 and 166 bp were generated in the primary and nested PCRs, respectively. In addition, an RLB assay was developed to identify nine different urogenital serovars of C. trachomatis (Ba, D, E, F, G, H, I, J, and K) and group controls, including group B (Ba, D, and E), group C (I, J, K, and H), and an intermediate group (F and G). Using this assay, we were able to type 81 of the 86 samples (94.2%). Of these samples, 91.3% were single C. trachomatis infections, and 8.7% were multiple infections. The most common serovars identified were serovars D (22.2%), F (18.5%), G (13.6%), and E (12.3%). Of the women with multiple C. trachomatis infections, >50% contained both serovars D and E. The nested VD2 PCR-RLB developed is a simple, fast, and specific method for the identification of individual urogenital C. trachomatis serovars previously detected by using plasmid PCR. Moreover, it is an appropriate method for studying multiple C. trachomatis infections and for use in large epidemiological studies.  相似文献   
144.
This qualitative study explored the process of help‐seeking and therapy among clients with religious or spiritual beliefs. Ten clients who were currently in, or had recently finished, therapy were interviewed. Participants reported using their religious or spiritual beliefs to cope with their psychological problems before and during therapy. Prior to therapy, they were worried that secular‐based help might weaken their faith. However, the experience of having psychological distress and the process of receiving therapy were both perceived as strengthening to faith and ultimately part of a spiritual journey. Contrary to expectations, a match between the spirituality or religious affiliation of the therapist and client was not considered important. This implies that the ‘religiosity gap’ between secular therapists and clients with religious/spiritual beliefs is bridgeable. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
145.
BACKGROUND: Depression is the most common mental health disorder in people aged over 65 years. Late-life depression is associated with chronic illness and disability. AIM: To investigate the feasibility of a collaborative care model for depression in older people in a primary care setting. DESIGN OF STUDY: Randomised controlled trial with 16-weeks follow up. SETTING: A primary care trust in Manchester. METHOD: Participants were 105 people aged 60 years or older who scored 5 or more on the Geriatric Depression Scale; 53 were randomly allocated to an intervention group and 52 to a usual care group. The intervention group received care managed by a community psychiatric nurse who delivered an intervention comprising a facilitated self-help programme with close liaison with primary care professionals and old-age psychiatry according to a defined protocol. The usual care group received usual GP care. A nested qualitative study explored the views of the health professionals and patients regarding the acceptability and effectiveness of the intervention. RESULTS: The main outcome measure was recovery from depression. Patients in the intervention group were less likely to suffer from major depressive disorder at follow up compared with usual care (0.32, 95% confidence = interval = 0.11 to 0.93, P = 0.036). The qualitative component of the study demonstrated the acceptability of the intervention to patients. CONCLUSION: A model of collaborative care for older people with depression, used in a primary care setting with a facilitated self-help intervention is more effective than usual GP care. This study demonstrates that the implementation of a collaborative care model is feasible in UK primary care and that the intervention is effective and acceptable to patients.  相似文献   
146.
Sera of mice sensitized with bacteria and subsequently challenged with lipopolysaccharide promote hemorrhagic necrosis of tumors in vivo and display cytotoxic activity against tumor cells in vitro, which has been attributed to the induction of tumor necrosis factor (TNF). Here, we describe the induction of a previously unrecognized antitumor activity in such sera, which is distinct from TNF but displays tumor-specific cytocidal activity in vitro as well as potent tumor-regressing activity in vivo. Biochemical analysis of this activity yielded a molecular mass of approximately 150 kDa, closely resembling a novel tumoricidal factor of murine macrophages (Mphi) termed MTC 170 (Mphi tumor cytotoxin, approximate molecular mass 170 kDa), which we have previously proposed to constitute a major effector pathway for the destruction of tumor cells by activated Mphi.  相似文献   
147.
Techniques have been developed to culture bovine or porcine vascular cells on polyglycolic acid (PGA) scaffolds to form engineered vessels. Previously, it was shown that smooth muscle cells (SMCs) that were in close proximity to PGA remnants after 8 weeks of culture had lower expression of SMC markers of differentiation and were more mitotic compared with SMCs that were distant from polymer residuals. Modifications of PGA were explored as a means to minimize residual polymer fragments after culture. To hasten degradation, polymer was treated with heat, NaOH, or gamma-irradiation. Differential scanning calorimetry, mass and tensile strength degradation, and inherent viscosity were used to assess polymer characteristics. When polymer was maintained in aqueous conditions, tensile strength of treated PGA degraded to zero within 3 weeks for each treatment. Engineered vessel constructs cultured on NaOH and gamma-treated polymer displayed smooth muscle alpha-actin throughout the vessel wall. Scaffold treatment impacted graft morphology, cellular differentiation, and mechanical integrity.  相似文献   
148.
Follicular lymphoma (FL) is characterized by t(14;18)(q32;q21), which is the initial genetic perturbation in this disease. Additional genetic mutations are required to generate a fully malignant phenotype. Secondary chromosomal alterations seen in FL include prominent involvement of chromosome 1 in the form of balanced or unbalanced translocations, insertions, deletions, and duplications involving both the p and q arms. We investigated a diagnostically well defined set of 55 t(14;18)-positive FL cases with complex karyotypes by means of multicolor karyotyping. Sixteen cases showed involvement of chromosome 1 and were analyzed in further detail by a novel multicolor banding technique for this chromosome. We defined three groups showing varying complexity of chromosome 1 alterations. The first group revealed simple translocations, such as t(1;2), t(1;6), t(1;8), and t(1;17), involving breakpoints on either the p or the q arm of chromosome 1. The second group showed more complex rearrangements with translocations, insertions, regional duplications, and involvement of more than one partner chromosome with either the p or the q arm of chromosome 1. The third group was defined by highly complex rearrangements involving translocations, regional duplications, amplifications, and intrachromosomal band relocations affecting the entire chromosome 1. All three groups shared interchromosomal rearrangements of chromosome 1 with chromosome 8, often involving the MYC protooncogene site, amplification involving region 1q21-q31, and deletion involving region 1p36. Thus, the use of sophisticated multicolor molecular cytogenetic assays in the investigation of malignant lymphoma allows precise characterization of chromosomal alterations and will provide a better understanding of their biology.  相似文献   
149.
Mode of delivery and risk of developing allergic disease   总被引:3,自引:0,他引:3  
The aim of this study was to quantify the relationship between mode of delivery and subsequent incidence of allergic disease. The analysis is based on data derived from a birth cohort of 24,690 children who contributed data to the West Midlands General Practice Research Database. We found no convincing evidence to suggest that babies born by caesarean, forceps, or breech delivery had an increased risk of developing allergic disease.  相似文献   
150.
Summary No data are available on the localization of Pepsinogen A (PGA=PG I) and Pepsinogen C (PGC=PG II) positive cells in Barrett's epithelium. Endoscopic biopsy specimens were taken from the columnar epithelium from 23 patients (n=93), and in addition from the cardia from eight healthy control subjects (n=38). The tissue was stained by the immunoperoxidase technique with specific anti-pepsinogen antisera, and double immunostained for PGA and PGC. In the Barrett's epithelium PGA was found in 28 out of 93 biopsy specimens (30.1%) and PGC in 55 out of 93 (59.1%). Chief cells always stained both for PGA and PGC, while clear mucous cells were often PGA– and PGC+. PGA+ and PGC+ cells were found each in 100% of the biopsy specimens with fundic type epithelium, in 21.7% and 70.7% of biopsy specimens with junctional type, in 0% and 26.1% of biopsy specimens with specialized epithelium and in 12.5% and 43.5% of biopsy specimens with mixed junctional/specialized features respectively. Dysplastic epithelium stained always negatively with both anti-pepsinogen antisera. In most control cardia biopsy specimens PGA as well as PGC were demonstrable; occasionally clear mucous glands were PGA– and PGC+.It is concluded that pepsinogen-containing cells can be accurately identified in the Barrett's epithelium; their presence seems related to the histological cell type. Identification of pepsinogen positive cells may contribute to a more accurate morphological classification of the Barrett's epithelium.Presented in part at the Annual Meeting of the American Gastroenterological Association, San Francisco, May 1986  相似文献   
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