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991.
A neonate with truncus arteriosus (type 1) and interrupted aortic arch (type A) associated with an excessively large gap between interrupted aortic segments underwent successful reconstruction of the aortic arch with a partial subclavian flap aortoplasty plus bovine jugular patch (Contegra 200, Medtronic, Inc, Minneapolis, MN) using continuous selective low-flow cardiopulmonary bypass without circulatory arrest. The ventricular septal defect was closed with a Dacron (IMPRA, Inc, Tempe, AZ) patch, and a Contegra prosthesis was used to re-establish right ventricle to pulmonary artery continuity. At an 18-month follow-up, the patient was free of symptoms with normal development. Echocardiography revealed a widely patent aortic arch and an unobstructed right ventricle to pulmonary artery connection.  相似文献   
992.
Biphosphonates (BPs) are widely used to inhibit osteoclastic activity in malignant diseases such as bone metastatic breast and prostate carcinoma. Recent studies reported that BPs could also cause a direct antitumor effect, probably due to their ability to interfere with several intracellular signalling molecules. The enzyme cyclooxygenase-2 (COX-2) and the epidermal growth factor receptor (EGFR) play an important role in the control of cancer cell growth and inhibitors of COX-2 and EGFR have shown antitumor activity in vitro and in vivo in several tumor types. We, and others, have previously shown that EGFR and COX-2 may be directly related to each other and that their selective inhibitors may have a cooperative effect. In the present study we have evaluated the combined effect of zoledronic acid, the most potent nitrogen-containing BP, with the COX-2 inhibitor SC-236 and the selective EGFR-tyrosine kinase inhibitor gefitinib, on breast and prostate cancer models in vitro and in xenografted nude mice. We show that combination of zoledronic acid with SC-236 and gefitinib causes a cooperative antitumor effect accompanied by induction of apoptosis and regulation of the expression of mitogenic factors, proangiogenic factors and cell cycle controllers both in vitro and in xenografted nude mice. The modulatory effect on protein expression and the inhibitory effect on tumor growth is much more potent when the three agents are used together. Since studies are ongoing to explore the antitumor effect of zoledronic acid, our results provide new insights into the mechanism of action of these agents and a novel rationale to translate this feasible combination treatment strategy into a clinical setting.  相似文献   
993.
In clinical practice, the clinician is challenged with symptoms and/or signs at times apparently insoluble by diagnostic and/or therapeutic means. We propose that in these cases, we have to use an EBM approach in which evidence may be looked up in every available clinical report and bibliographic databases are used for searching that evidence. We report on a case of ulcerative skin lesions apparently insoluble by expert dermatologists following a conventional diagnostic and therapeutic process. We use this case report for illustrating a systematic approach to resolve diagnostic and therapeutic questions using a bibliographic database search (like MEDLINE and EMBASE). Both a systematic approach to bibliographic databases and a critically appraised topic on case reports (or case series) are needed to 'rehabilitate' low-level evidences (that is a case report or case series) to a higher level when we approach decision-making of uncommon clinical pictures. We demonstrate the possibility of using bibliographic databases to search and retrieve useful information for decision-making of uncommon clinical pictures. The method we have proposed can be applied in every area of the world, especially in rural areas. Finally, an Internet-shared database of uncommon clinical pictures with critically appraised topics could be useful in saving more time.  相似文献   
994.
995.
Staphylococcus haemolyticus strains (n=20), responsible of blood stream infections, were consecutively isolated from patients hospitalized in two different wards at high risk of infection. Strains displayed high rate of resistance to oxacillin (90%). All strains but two with decreased susceptibility (MIC = 4 microg/mL), were sensitive to vancomycin. Ten strains were resistant to teicoplanin. Among the strains susceptible to glycopeptides, three displayed heteroresistance to vancomycin and seven to teicoplanin, when tested by Etest technique with 2 x McFarland inoculum. Biochemical reactions allowed to assign strains to eight biotypes, with 11 strains clustering under two main biotype A and biotype B. Pulsed-field-gel-electrophoresis (PFGE) identified 11 different PFGE-types. Seven strains grouping under the major PFGE-type 1 and three strains clustering in PFGE-type 2, closely correlated to biotype A and biotype B respectively. Seven teicoplanin-resistant isolates clustered in the PFGE-type 1, two in the PFGE-type 2 and one in PFGE-type 5. Therefore, teicoplanin-resistant strains were biochemically and genetically related and clonally distributed, despite different clones of S. haemolyticus circulated in the units during the study period.  相似文献   
996.

Objective

Given the increased pressure from governmental programs to restructure reimbursements to reflect quality metrics achieved by physicians, review of current reimbursement schemes is necessary to ensure sustainability of the physician's performance while maintaining and ultimately improving patient outcomes. This study reviewed the impact of reimbursement incentives on evidence-based care outcomes within a vascular surgical program at an academic tertiary care center.

Methods

Data for patients with a confirmed 30-day follow-up for the vascular surgery subset of our institution's National Surgical Quality Improvement Program submission for the years 2013 and 2014 were reviewed. The outcomes reviewed included 30-day mortality, readmission, unplanned returns to the operating room, and all major morbidities. A comparison of both total charges and work relative value units (RVUs) generated was performed before and after changes were made from a salary-based to a productivity-based compensation model. P value analysis was used to determine if there were any statistically significant differences in patient outcomes between the two study years.

Results

No statistically significant difference in outcomes of the core measures studied was identified between the two periods. There was a trend toward a lower incidence of respiratory complications, largely driven by a lower incidence in pneumonia between 2013 and 2014. The vascular division had a net increase of 8.2% in total charges and 5.7% in work RVUs after the RVU-based incentivization program was instituted.

Conclusions

Revenue-improving measures can improve sustainability of a vascular program without negatively affecting patient care as evidenced by the lack of difference in evidence-based core outcome measures in our study period. Further studies are needed to elucidate the long-term effects of incentivization programs on both patient care and program viability.  相似文献   
997.
Human alpha defensin in HIV-exposed but uninfected individuals   总被引:1,自引:0,他引:1  
Human alpha defensins 1, 2, and 3 are produced by CD8 T cells of HIV-infected long-term nonprogressors and have an antiviral activity. alpha Defensins were examined in peripheral blood mononuclear cells (PBMCs), cervical-vaginal mononuclear cells (CVMCs), and cervical biopsies of 9 HIV-1-exposed but uninfected women (ESNs), 10 HIV-infected patients (HIV), and 13 low-risk healthy controls (HCs). Results showed that, whereas alpha defensin production and alpha defensin-expressing CD8 lymphocytes were comparable in ESNs and HIV patients, constitutive alpha defensin production by peripheral CD8 and CVMCs was augmented in ESNs compared with HCs (P = 0.001 and P = 0.058, respectively); alpha defensin mRNA was increased in PBMCs of ESNs; unstimulated, alpha defensin-expressing peripheral and mucosal CD8 lymphocytes were 10-fold higher in ESNs compared with HCs (P = 0.003 and P = 0.01, respectively); and alpha defensin mRNA and alpha defensin-expressing cells were augmented in cervical biopsies of ESN compared with HCs (mRNA:P = 0.03). The differences were reduced upon in vitro mitogen stimulation. A robust constitutive production of alpha defensin is seen in HIV-exposed uninfected individuals; these peptides could have a role in the potentially protective immune response that characterizes ESNs.  相似文献   
998.
999.
For the first time, a conventional analysis of C-banded karyotypes was carried out in two distantly related diplopod species; this revealed an impressive percentage of heterochromatin in both genomes. In Acanthopetalum sicanum (Order Callipodida) (2n = 12), heterochromatin constitutes about 60% of the total DNA in females and 56% in males, whereas in Enologus oxypygum (Order Julida) (2n = 22) it is about 67% in both sexes. Heterochromatin of the two species was found to be similar in base composition (AT rich) and heterochromatin distribution, indicating that it has accumulated in a species-specific manner. Sex-determining mechanisms of the XY type were detected in both A. sicanum and E. oxypygum. In A. sicanum, the Y presented the lowest heterochromatic content of all chromosomes in the karyotype, whereas the X presented the highest.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   
1000.
This study has examined endometrial tissue in 14 normal women prior to insertion of a levonorgestrel-releasing intrauterine system (LNG-IUS) and thereafter longitudinally for up to 12 months post-insertion. The specific endpoints examined by immunohistochemistry were progesterone receptor (PR) subtypes A + B, oestrogen receptor (ER) and prostaglandin dehydrogenase (PGDH). Two antiprogesterone receptor antibodies, one specific to PR(B) subtype and the other to PR subtype A + B, were employed to examine the localization of both PR isoforms. The activity of PGDH, a progesterone dependent enzyme, was also measured. ER and PR(A+B) and PR subtype B were significantly down-regulated in glands and stroma in the presence of continuous intrauterine LNG delivery. There was an apparent increase in PR(A) immunoreactivity in endometrial glands between 6 and 12 months post-insertion. Consistent with down- regulation of both isoforms of PR was reduced glandular PGDH immunostaining following LNG-IUS insertion, and PGDH activity (as measured by metabolism of excess substrate in vitro). Furthermore, PGDH activity, known to be localized in the glands, significantly increased (P < 0.05) at 12 months post-insertion, coinciding with the observed increase in glandular PR(A+B) immunoreactivity at this time. Since the LNG-IUS suppresses the PR(B) so strongly, PR(A) is likely to be the subtype that mediates long term LNG action in the endometrium. PR(B) is the more suppressed of the two subtypes, and only PR(A) rises along with PGDH activity. Alterations to normal endometrial morphology and function, e.g. perturbation of normal sex steroid receptor expression, following exposure to high concentrations of local LNG, may play a role in the aetiology of bleeding disorders associated with the LNG-IUS. Further elucidation of local uterine mediators involved in the mechanism of bleeding problems is required.   相似文献   
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