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41.

Objective

to explore the motivations and beliefs of commencing midwifery students against a background of high course demand and high student attrition.

Design

a qualitative analysis of student reflective essays.

Setting

Melbourne, Australia.

Participants

all commencing midwifery students, in 2008, were invited to participate (n=41).

Measurements and findings

three primary motivations for choosing midwifery were identified, including: notions of altruism (wanting to help), a fascination with pregnancy and birth, and a view of midwifery as a personally satisfying career.

Key conclusions and implications for practice

Bachelor of Midwifery programmes attract students with idealised views about midwifery practice. Such views may lead to student disillusionment, tensions with educators and clinicians, and higher rates of student attrition. Students need greater support to examine their views about midwifery practice. More meaningful support may assist the students' successful socialisation into clinical practice.  相似文献   
42.
43.
Background: Microbial translocation (MT) is a shared feature of HIV infection and inflammatory bowel disease (IBD). Aims: This study was conducted to assess the impact of IBD (and particularly ulcerative colitis, UC) on plasma markers of MT and immune activation in HIV+ subjects.

Methods: A cross-sectional study was conducted in 3 groups of patients: HIV+/UC+(group HIV/UC); HIV+/UC- (group HIV); HIV-/UC+(group UC). Plasma levels of soluble CD14 (sCD14), intestinal fatty acid-binding protein (I-FABP), and endotoxin core antibodies (endoCAB) were measured as plasma markers of MT. Inflammation and immune activation were evaluated by measuring plasma levels of IL-6, IL-21, TNF-alpha, and high-sensitivity C-reactive protein (hs-CRP). T- and B-cells subpopulations were characterized by FACS analysis.

Results: Seven patients were enrolled in group HIV/UC, 9 in HIV, and 10 in UC. All HIV-positive patients had plasma values of HIV-1 RNA < 37 copies/mL for at least 12 months and good immunological recovery. All patients with UC were treated with oral mesalazine. Markers of MT, immune activation, and inflammation were not increased in subjects with HIV/UC. In fact, they had lower levels of I-FABP (p = 0.001) and sCD14 (p = 0.007) when compared to other patients groups. Positive correlations were found between I-FABP and sCD14 (r = .355, p = 0.076). Frequency of T- and B-cell subsets did not differ among groups.

Conclusions: Our results suggest that UC does not worsen MT, inflammation, or immune activation in HIV-infected subjects. The anti-inflammatory activity of chronic mesalazine administration on intestinal mucosa may contribute to this finding.  相似文献   

44.
45.

Background  

The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls.  相似文献   
46.
Targeted gene disruption of murine CD7   总被引:2,自引:0,他引:2  
CD7 is a 40 kDa type I transmembrane glycoprotein member of the Ig superfamily. CD7 is a marker of mature human T cells and NK cells, and is expressed early in their development. Cross-linking CD7 positively modulates T cell and NK cell activity as measured by calcium fluxes, expression of adhesion molecules, cytokine secretion and proliferation. CD7 associates directly with phosphoinositol 3'-kinase, and CD7 ligation induces production of D-3 phosphoinositides and tyrosine phosphorylation. Severe combined immunodeficiency has been associated with a lack of lymphocyte surface CD7. The CD7 ligand is unknown. The murine CD7 homolog is encoded by a single gene on chromosome 11. In order to characterize the role of CD7 in lymphocyte development and function we have eliminated the CD7 gene by targeted disruption. CD7- deficient mice display normal histology of thymus and spleen, normal lymphocyte populations in primary and secondary lymphoid tissues, and normal serum Ig levels. Specific antibody responses after immunization with T-dependent and T-independent antigens are equivalent in wild-type and CD7 knockout mice. CD7-deficient lymphocytes respond normally to T cell mitogenic and allogeneic stimuli, and display normal NK cell cytotoxicity.   相似文献   
47.
In the present study we investigated the potential role of Toll-like receptor 4 (TLR-4) Asp299Gly and Thr399Ile polymorphisms as risk factors in the development of gastric cancer. TLR-4 Asp299Gly and Thr399Ile polymorphisms were investigated in 171 Italian patients with sporadic gastric cancer and in 151 controls. Unconditional regression (odds ratio and 95% confidence intervals) were used to investigate the association of the studied polymorphisms with gastric cancer. TLR-4 Thr399Ile polymorphism is linked with an increased susceptibility to gastric cancer (P = 0.023 and hazard ratio = 3.62). No significant association for TLR-4 Asp299Gly polymorphism was found. In the subgroup of patients with intestinal-type gastric cancer, a significant risk of gastric cancer was associated with TLR-4 Thr399Ile genotype (P = 0.006). Our results demonstrated that TLR-4 Thr399Ile polymorphism is linked with an increased susceptibility to gastric cancer. An increased risk for intestinal gastric cancer in carriers of the TLR4 Thr399Ile allele was observed. Future epidemiological studies should consider the possible interactions between proinflammatory genotypes (such as TLR and interleukin-1R polymorphisms) and other risk factors for cancer such as dietary habits and/or exposure to environmental carcinogens.  相似文献   
48.
Kibar Z, Salem S, Bosoi CM, Pauwels E, De Marco P, Merello E, Bassuk AG, Capra V, Gros P. Contribution of VANGL2 mutations to isolated neural tube defects. Vangl2 was identified as the gene defective in the Looptail (Lp) mouse model for neural tube defects (NTDs). This gene forms part of the planar cell polarity (PCP) pathway, also called the non‐canonical Frizzled/Dishevelled pathway, which mediates the morphogenetic process of convergent extension essential for proper gastrulation and neural tube formation in vertebrates. Genetic defects in PCP signaling have strongly been associated with NTDs in mouse models. To assess the role of VANGL2 in the complex etiology of NTDs in humans, we resequenced this gene in a large multi‐ethnic cohort of 673 familial and sporadic NTD patients, including 453 open spina bifida and 202 closed spinal NTD cases. Six novel rare missense mutations were identified in seven patients, five of which were affected with closed spinal NTDs. This suggests that VANGL2 mutations may predispose to NTDs in approximately 2.5% of closed spinal NTDs (5 in 202), at a frequency that is significantly different from that of 0.4% (2 in 453) detected in open spina bifida patients (p = 0.027). Our findings strongly implicate VANGL2 in the genetic causation of spinal NTDs in a subset of patients and provide additional evidence for a pathogenic role of PCP signaling in these malformations.  相似文献   
49.
In a prospective, randomized, double-blind study, 49 patients underwent lumbar myelography using iotrol (24 patients) or metrizamide (25 patients). The diagnostic imaging adequacy of iotrol was comparable with that of metrizamide. After iotrol myelography, adverse reactions were fewer, less severe, and of shorter duration than were those following metrizamide myelography. Thirteen of 24 patients (54%) receiving iotrol reported some adverse reactions compared with 24 of 25 patients (96%) receiving metrizamide. Five moderate and one severe adverse reaction occurred in the group receiving iotrol. Fourteen moderate and eight severe adverse reactions occurred in the group receiving metrizamide. Thirty-eight patients underwent electroencephalography both before and after myelography (19 iotrol and 19 metrizamide). None of the EEGs obtained after iotrol myelography changed from baseline, while seven of the EEGs obtained after metrizamide myelography showed changes from baseline. Iotrol was judged superior to metrizamide as a contrast medium in this patient population.  相似文献   
50.
Galluzzo  A.  Giordano  C.  Rubino  G.  Bompiani  G. D. 《Diabetologia》1984,26(6):426-430
Summary Humoral and cell-mediated disorders in Type 1 (insulin-dependent) diabetes suggest that an imbalance of immunoregulatory T-cell subsets exists. In 23 newly diagnosed (onset < 3 months) and 21 long-standing Type 1 diabetic patients, T lymphocyte subsets were analyzed using monoclonal antibodies (OKT3, OKT4, OKT8, OKM1). The newly diagnosed patients showed a reduction with a significant difference from healthy controls in total T cells (OKT3+: 58.1 ±8.5% versus 70.7±8.0%), helper/inducer cells (OKT4+: 33.8 ±7.0% versus 47.1 ±8.3%), suppressor/cytotoxic cells (OKT8+: 18.5±7.3% versus 32 ± 6.8%) and monocytes (OKM1+: 11.5±3.8% versus 19.9±5.2%) (p< 0.001). The long-standing diabetic patients also revealed a low number of immunoregulatory T cells compared with control subjects, although to a lesser extent (p< 0.01–0.05). The helper/suppressor ratio (OKT4+/OKT8+) was higher in newly diagnosed patients than in control subjects (2.2±1.3 versus 1.5±0.3; p< 0.02). When compared with 95% tolerance limits in the control subjects, the reduction of OKT8+ cells in the newly diagnosed diabetic patients appeared more marked: the mean (18.5%) coincided with the lower limit of normal subjects (18.3%). Ten of the newly diagnosed Type 1 diabetic patients had a value below the normal lower limit. Our data point to the occurrence of different immunoregulatory abnormalities in newly diagnosed Type 1 diabetic patients, especially in OKT8+ and OKT4+ cells. The imbalance in T lymphocyte subsets is further proof of the role of cellular autoimmunity in the pathogenesis of the early phases of Type 1 diabetes.  相似文献   
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