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1.

Background

Limited data exists demonstrating the efficacy of minimally invasive surgery (MIS) compared to median sternotomy (MS) for multiple valvular disease (MVD). This systematic review and meta-analysis aims to compare operative and peri-operative outcomes of MIS vs MS in MVD.

Methods

PubMed, Ovid, and Embase were searched from inception until August 2019 for randomized and observational studies comparing MIS and MS in patients with MVD. Clinical outcomes of intra- and postoperative times, reoperation for bleeding and surgical site infection were evaluated.

Results

Five observational studies comparing 340 MIS vs 414 MS patients were eligible for qualitative and quantitative review. The quality of evidence assessed using the Newcastle-Ottawa scale was good for all included studies. Meta-analysis demonstrated increased cardiopulmonary bypass time for MIS patients (weighted mean difference [WMD], 0.487; 95% confidence interval [CI], 0.365-0.608; P < .0001). Similarly, aortic cross-clamp time was longer in patients undergoing MIS (WMD, 0.632; 95% CI, 0.509-0.755; P < .0001). No differences were found in operative mortality, reoperation for bleeding, surgical site infection, or hospital stay.

Conclusions

MIS for MVD have similar short-term outcomes compared to MS. This adds value to the use of minimally invasive methods for multivalvular surgery, despite conferring longer operative times. However, the paucity in literature and learning curve associated with MIS warrants further evidence, ideally randomized control trials, to support these findings.
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INTRODUCTION: Human Papillomavirus (HPV) infection is considered an important risk factor for the development of cervical carcinoma. The aim of this work was to detect and genotype HPV DNA in cervical lesions from our Province. METHODS: HPV DNA was amplified by polymerase chain reaction (PCR) and genotyped by restriction fragment length polymorphism (RFLP) analysis. A total of 101 biopsies (43 koilocytic atypias, 20 CIN1, 19 CIN2, 17 CIN3 and 2 squamous carcinomas) were analyzed. RESULTS: HPV DNA was found in 41.8% of koilocytic atypias, in 95.0% of CIN1 and 100% of CIN2 and higher grade lesions. Only high risk genotypes were found in CIN2-3 and invasive carcinomas. HPV 16 was the most prevalent type in both CIN1 and CIN2-3 and the only HPV type found in situ and invasive carcinomas. HPV type 51 was found in 21.0% of CIN1 but it was rare in CIN2 and absent in more advanced lesions.  相似文献   
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Histamine, specific H1-and H2-receptor agonists in conjunction with specific H1-and H2-receptor antagonists and other types of classical antagonists were used to characterize histamine receptors in the vasa deferentia of mice, rats and guinea pigs. The H1-receptor mediates contraction while the H2-receptor produces inhibition. There were marked qualitative and quantitative differences in the distribution of the two types of histamine receptors in the vas deferens of different species. Results indicate that mouse and rat vas deferens contain an inhibitory H2-receptor, but virtually no excitatory H1-receptor. In contrast, guinea pig vas deferens contained an excitatory H1-receptor but was essentially devoid of an inhibitory H2-receptor. The rank order of relative potencies of various agonists as well as the calculated pA 2 values of cimetidine in the mouse and rat vas deferens suggest that the two species probably have the same H2-receptor. High concentrations of histamine and 2-methyl histamine have a stimulant action in the mouse and rat vas deferens which was secondary to release of endogenous noradrenaline rather than to the stimulation of an excitatory H1-receptor.  相似文献   
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The effect of histamine on adrenergic neurotransmission in the mouse isolated vas deferens preparation was investigated. Concentrations of histamine ranging from 0.2 to 650 M depressed, in a dose-related manner, not only the contractile response elicited by field stimulation but also the response caused by the addition of exogenous noradrenaline and acetylcholine. However, the release of [3H]-NA evoked by field stimulation or by high K+ remained unchanged in the presence of these concentrations of histamine. The inhibitory effect of histamine on the contractile responses caused by various stimuli was reduced or completely antagonized by cimetidine, a histamine H2-receptor antagonist but not by mepyramine, a conventional antihistamine. The inhibitory effect of histamine was found to be inversely proportional to both the Ca2+ concentration in the bathing medium and to the frequency of field stimulation. Further, the inhibitory effect of histamine was markedly reduced when Mg2+ was omitted from the bathing medium. It is concluded that the mouse vas deferens preparation contains a post-junctional inhibitory H2-receptor. The stimulation of H2-receptors by histamine inhibits the contractile response of the vas deferens, possibly by decreasing the availability of Ca2+ required for contraction by depressing the influx of Ca2+.  相似文献   
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In order to understand the mechanism of unresponsiveness towards Mycobacterium leprae antigens in leprosy, we evaluated the role of M. leprae sonicate antigens in regulating the expression of the costimulatory molecules B7-1, CD28, intercellular adhesion molecule-1 (ICAM-1), LFA-1α, LFA-1β and Mac-1 on the lymphocytes of both leprosy patients and healthy subjects. It was observed that the expression of B7-1 and CD28 was significantly decreased but the levels of ICAM-1 and LFA-1α were increased in patients with untreated borderline leprosy (BL)/lepromatous leprosy (LL) disease. No remarkable change was noticed in the case of borderline tuberculoid (BT) leprosy or treated BL/LL patients. Further, a striking finding was that lymphocytes from healthy subjects cultured with a particularly high dose of M. leprae sonicate antigens down-regulated the expression of B7-1 and CD28 molecules, but up-regulated the display of ICAM-1 and LFA-1α. Furthermore, proliferation induced by M. leprae sonicate was inhibited only by anti-B7-1 antibody. Mycobacterium leprae antigen-induced suppression of the proliferation of lymphocytes of healthy volunteers and LL patients was reversed by culturing the lymphocytes with purified protein derivative (PPD). It may be concluded from the findings in this study that down regulation of B7-1 and CD28 in BL/LL leprosy patients may be responsible for a defective T cell signalling by the B7-1/CD28 pathway caused by M. leprae antigens. This may lead to clonal inactivation of M. leprae-reactive T cells, consequently the bacilli grow without restriction in macrophages.  相似文献   
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Of 613 children evaluated in a village in Haryana 94 (15.3%) were observed to have chronic suppurative otitis media (CSOM). Fifty eight (61.7%) children had hearing impairment. CSOM contributed to 71.6% of the hearing impaired (58/81). On analysis of association of CSOM with literacy and socio-economic status of mothers, and age, sex, and upper respiratory tract infections (URI) in children positive correlation was observed only with URIs (P<0.001). Literacy and socio-economic status of the mothers did not correlate significantly with knowledge about treatment seeking, and ear cleaning practices, probably due to the narrow range of incomes and literacy levels. An intervention program consisting of play, demonstrations, health charts and slogans, and aural cleaning and antibiotic drops was introduced.  相似文献   
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