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21.
This paper presents a study that aimed to develop and validate a theory-based instrument for the assessment of readiness to change for interprofessional collaboration in healthcare (IPC-TTM). The instrument was developed in the Persian language and tested in the Iranian context. Healthcare professionals from medical and nursing professions participated in the assessment of validity and reliability of the instrument. We conducted this psychometric study in two phases: First, the questionnaire was developed based on the transtheoretical model (TTM) through literature review and expert panel. Then, in the validation phase, we held three modified Delphi rounds to assess the content and face validity of the questionnaire. We used confirmatory factor analysis (CFA) to evaluate the fit of the questionnaire as applied to modified TTM. Reliability of the final instrument was tested by assessing the test-retest reliability of instrument items with Kappa coefficient. We also calculated the intraclass correlation coefficient (ICC) and Cronbach’s alpha to assess the test-retest reliability and internal consistency of the instrument sub-scales. The initial item pool consisted of 30 items and three sub-scales (Attitude, Intention, and Action). The content validity of the questionnaire was confirmed with 17 items. Based on the CFA results two additional items were deleted to increase the fit of the model. The final instrument was confirmed with 15 items and three sub-scales. Reliability assessment on the 15-item instrument showed an acceptable test-retest reliability of the instrument items. ICC values for the Attitude, Intention, and Action sub-scales of the instrument were calculated as 0.82, 0.73, and 0.71, respectively. Moreover, Cronbach’s alpha for the Attitude, Intention, and Action sub-scales were 0.85, 0.73, and 0.77, respectively. This study offers a new theory-based instrument to measure readiness to change for interprofessional collaboration in healthcare in the Iranian context. The questionnaire can be used for ‘needs assessment’ in developing tailored educational interventions and self-assessments in interprofessional education studies.  相似文献   
22.
OBJECTIVES: To investigate HLA-DRB1, DQA1 and DQB1 allelic polymorphism in Iranian patients with pulmonary tuberculosis (PTB). METHODS: Forty patients with smear-positive PTB and 100 healthy individuals as a control group were studied for MHC class II allelic polymorphism by polymerase chain reaction with sequence-specific primers (PCR-SSP). The primer was supplied by biotest in the standard kit. DRB low resolution SSP and DQA, DQB intermediate resolution SSP was applied. RESULTS: The comparison of the patients and the control group showed a significant increase in the frequency of the HLA-DRB1*07 and DQA1*0101 alleles (OR 2.7, 95%CI 1.19-6.13, P = 0.025 and OR 2.66, 95%CI 1.15-6.44, P = 0.04, respectively) in the patient group. The frequency of DQA1*0301 and DQA1*0501 was also significantly decreased (OR 0.254, 95%CI 0.075-0.865, P = 0.033 and OR 0.53, 95%CI 0.3-0.95, P = 0.045, respectively) in the PTB patients. Concerning haplotype frequency, DRB1*11501, QDQA1*0103 and DQB1*0601 were increased, but this difference was not statistically significant. In the DQB1 locus, DQB1*0501 was non-significantly over-represented. CONCLUSIONS: HLA-DRB1*07 and HLA-DQA1*0101 appeared to be the predisposing alleles and HLA-DQA1*0301 and 0501 the protective alleles in our patients with TB.  相似文献   
23.
PurposeRenal Resistive Index (RRI) is a newly introduced sonographic index in predicting contrast-induced nephropathy (CIN) development. It has been suggested that RRI > 0.69 should be considered as a risk factor for CIN development. The present study aimed to calculate the predictive value of RRI using a cutoff point of 0.69.MethodsA total of 90 patients who were a candidate for coronary vessels angiography were enrolled in this study. Color Doppler ultrasonography was performed and RRI was measured. Patients were followed up for 48 hours after contrast media exposure for the CIN development. The diagnosis of CIN was based on a 25% relative rise or 0.5 mg/dL absolute rise in creatinine level. The predictive values of RRI were measured using 0.69 as a cutoff point.ResultsOut of 90 patients, CIN developed in 3 patients and 17 patients had preprocedural RRI > 0.69. Of 3 patients with CIN, 1 had RRI > 0.69. Using 0.69 as the cutoff point, the measured sensitivity and specificity of RRI were 33.3% and 83.9%, respectively.ConclusionsRRI > 0.69 is not a sensitive index in predicting the CIN development and cannot be used as an independent factor.  相似文献   
24.
Besides the use of autologous bone grafting several osteoconductive and osteoinductive methods have been reported to improve bone healing. However, persistent non‐union occurs in a considerable number of cases and compromised angiogenesis is suspected to impede bone regeneration. Hyperbaric oxygen therapy (HBO) improves angiogenesis. This study evaluates the effects of HBO on bone defects treated with autologous bone grafting in a bone defect model in rabbits. Twenty‐four New‐Zealand White Rabbits were subjected to a unilateral critical sized diaphyseal radius bone defect and treated with autologous cancellous bone transplantation. The study groups were exposed to an additional HBO treatment regimen. Bone regeneration was evaluated radiologically and histologically at 3 and 6 weeks, angiogenesis was assessed by immunohistochemistry at three and six weeks. The additional administration of HBO resulted in a significantly increased new bone formation and angiogenesis compared to the sole treatment with autologous bone grafting. These results were apparent after three and six weeks of treatment. The addition of HBO therapy to autologous bone grafts leads to significantly improved bone regeneration. The increase in angiogenesis observed could play a crucial role for the results observed. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:513–520, 2015.  相似文献   
25.
Rezaie  AR; Esmon  CT 《Blood》1994,83(9):2526-2531
Protein C is a vitamin K-dependent plasma serine protease zymogen, which upon activation, functions as an anticoagulant. Protein C activation is catalyzed by a complex of thrombin (T) with thrombomodulin (TM). This activation is Ca(2+)-dependent, but Ca2+ inhibits protein C activation by thrombin alone. In most proteases, specificity is determined primarily by the residues that lie near the scissile bond. In protein C, the P2 position is Pro, whereas in the fibrinogen A chain, P2 is Val. We have expressed a Pro-->Val mutant of protein C (P168V) in mammalian cells. At saturating Ca2+, the P168V and wild-type proteins were activated by the T-TM complex equivalently, but half maximal rates of activation were obtained at 50 mumol/L Ca2+ for wild type and approximately 5 mmol/L Ca2+ for the P168V mutant. In the absence of TM, Ca2+ no longer inhibited the activation of the P168V mutant. These results indicate that Pro168 influences the Ca(2+)- dependent conformational changes in protein C that control activation. Recently, a patient with thrombotic complications has been identified with a Pro168-->Leu substitution. Both the P168V and the P168L mutation lead to impaired secretion caused by retention within the cell.  相似文献   
26.
The existence and characteristics of bone marrow T-cell progenitors have not yet been established in man. Several pieces of evidence such as the reconstitution of certain immunodeficiencies by bone marrow graft suggest that T-cell precursors are present in the bone marrow. We report the growth of T-cell colonies from bone marrow populations using PHA-stimulated lymphocyte-conditioned medium containing T-cell growth factor (TCGF). Rosetting experiments and complement-dependent cytotoxicity assays with monoclonal antibodies indicate that the bone marrow T colony-forming cells (T-CFC) are E- OKT 3- and la+, i.e., immature progenitors. The colonies derived from these cells have the phenotype of mature T cells: E + OKT 3 + la- with either helper (OKT 4+) and suppressor (OKT 8 +) antigens. These results suggest that a thymic microenvironment may not be necessary for the in vitro proliferation and differentiation of the T-cell lineage in adult humans. These methodologies may permit direct investigation of early phenomena concerning the T-cell lineage, such as the acquisition of self-tolerance, the formation of a repertoire of specificities, and the HLA restriction phenomena that we believe takes place before the thymic maturation.  相似文献   
27.
Purpose  The study investigated the impact of prior abdominal surgery on conversions and outcomes of laparoscopic right colectomy. Methods  A consecutive series of 414 patients with cancer or adenomas who underwent a laparoscopic right colectomy from March 1996 to November 2006 were studied for surgical conversions and outcomes. Conversion was defined as an incision length > 7 cm. Results  Patients with prior abdominal surgery (n = 191) were compared with patients with no prior abdominal surgery (n = 223), and showed no significant differences in age, ASA classification, length of stay, operative time, blood loss, harvested nodes, tumor size, and specimen length. Significantly more wound infections occurred in the prior abdominal surgery group (22 vs.12, P = 0.023). Body mass index > 30 showed a three-fold increased risk of conversion. Fifteen percent of the no prior abdominal surgery patients and 17 percent of the prior abdominal surgery patients were converted (P > 0.05). Conversion was associated with a longer mean length of stay (8.8 days) relative to laparoscopically completed cases (6.3 days) regardless of prior abdominal surgery history (P < 0.0001). Conclusions  Laparoscopic right colectomy for neoplasia was not associated with a higher conversion rate or morbidity in patients with prior abdominal surgery. Prior abdominal surgery is not a contraindication to laparoscopic right colectomy. Presented at the 15th International Congress of the European Association of Endoscopic Surgery, Athens, Greece, July 4 to 7, 2007.  相似文献   
28.
Lineage-restricted regulation of the murine SCL/TAL-1 promoter   总被引:10,自引:2,他引:10  
  相似文献   
29.
30.

Context:

Occult hepatitis B virus (HBV) status (OHBS) is simply defined as the presence of HBV DNA in the liver (with or without detectable HBV DNA in the serum), in the absence of serum HBV surface antigen (HBsAg). Importance of OHBS is mostly clinical, related to its possible role in spreading through blood transfusion and liver transplantation; causing classic forms of HBV. Mechanisms underlying this entity are poorly defined. Several possibilities have been suggested, with major classification into two groups: defective host immune response and viral replication activity through mutations of HBV DNA sequence. Mutations are extensively investigated in all four overlapping open reading frames (ORFs) of HBV genome, to define their possible role in the pathogenesis of OHBS. Some of these mutations like S-escape mutants could not be detected by the routine available assays, making them difficult to diagnosis. Therefore, trying to detect this covert condition could be more helpful for defining better preventive and therapeutic strategies.

Evidence Acquisition:

In the present study we provided an in-depth review of the most important new data available on different mutations in HBV genome of patients with OHBS, which may play a role in the pathogenesis of OHBS. The data were collected through reviewing the full-text articles, identified by the PubMed search, using the following keywords and their different combinations: occult hepatitis B, HBV genome, "a" determinant, HBV open reading frames, S mutations, X mutations, P mutations and C mutations.

Results:

Variants within the major hydrophilic region (MHR) of the HBsAg, deletions in the pre-S1region, codon stop in the S open reading frames (ORF), sporadic non common mutations, some mutations affecting the posttranslational production of HBV proteins in the S ORF like deletion mutations, mutations in start codon and nucleotide changes in the X ORF, deletion and point mutations in P ORF and sometimes, nucleotide substitution in the C ORF are among the assumed mutations detected to have a role in OHBS appearance.

Conclusions:

Studies mostly lacked a control group and the whole-length HBV sequencing was scant with conflicting results, suggesting that OHBS is often a result of multiple mechanisms. Additional studies on full-length HBV genomes from occult and non-occult HBV cases may shed more light on the interplay between different mechanisms involved in the pathogenesis of OHBS.  相似文献   
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