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目的了解辖区手足口病重症病例的流行病学特征,为制定干预措施提供依据。方法对2009年所有手足口病重症病例进行个案调查,并对调查资料进行流行病学分析。结果辖区手足口病重症病例发病高峰为4月份至7月份,职业全部为学龄前儿童,年龄以3岁及3岁以下婴幼儿为主,男性明显多于女性,多数有发热、出疹症状,绝大多数患儿精神、饮食不佳,病原以EV71感染为主。结论对手足口病重症病例要早发现、早诊断、早治疗,以降低病死率。  相似文献   
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Aim: Hyaluronan (HA) is an important extracellular matrix (ECM) proteoglycan. The localization of HA and its binding receptors, CD44 and LYVE‐1, was evaluated in an experimental model of chronic cyclosporine A (CsA)‐induced nephropathy. Methods: Sprague–Dawley rats maintained on a low‐salt diet (0.05% sodium) received an s.c. injection of vehicle (1 mL/kg per day olive oil; VH groups) or CsA (15 mg/kg per day; CsA groups) for 1 or 4 weeks. Induction of chronic CsA nephropathy was evaluated according to renal function and pathology and expression of HA, CD44, LYVE‐1, ED‐1 and α‐smooth muscle actin (α‐SMA). Results: CsA treatment for 4 weeks caused renal dysfunction, which was accompanied by typical striped interstitial fibrosis. In the VH group, HA immunoreactivity was observed only in the inner medulla. However, the area of HA immunoreactivity increased with the duration of CsA treatment: CsA treatment for 1 week extended HA immunoreactivity to the outer medulla, and CsA treatment for 4 weeks caused a further extension of HA immunoreactivity to the cortex, which was vulnerable to CsA‐induced renal injury. HA binding receptor, CD44 and LYVE‐1 expression were also upregulated in the CsA groups, and were localized to the area of fibrosis and the peritubular capillaries of the cortex. In the CsA groups, ED‐1 and α‐SMA were predominantly expressed in fibrotic areas in which HA had accumulated. Conclusion: These findings suggest that upregulation of HA and its binding receptors are involved in interstitial fibrosis in chronic CsA‐induced renal injury.  相似文献   
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Influence of Slow Pathway Ablation on Atrial Fibrillation. Introduction : The mechanisms whereby radiofrequency catheter modification of AV nodal conduction slows the ventricular response are not well defined. Whether a successful modification procedure can be achieved by ablating posterior inputs to the AV node or by partial ablation of the compact AV node is unclear. We hypothesized that ablation of the well-defined slow pathway in patients with AV nodal reentrant tachycardia would slow the ventricular response during atrial fibrillation.
Methods and Results : In 34 patients with dual AV physiology and inducible AV nodal reentrant tachycardia, atrial fibrillation was induced at baseline and immediately after successful slow pathway ablation and at 1-week follow-up. The minimal, maximal, and mean RR intervals during atrial fibrillation increased from 353 ± 76,500 ± 121, and 405 ± 91 msec to 429 ± 84 (P < 0.01), 673 ± 161 (P < 0.01), and 535 ± 98 msec (P < 0.01), respectively. These effects remained stable during follow-up at 1 week. The AV block cycle length increased from 343 ± 68 msec to 375 ± 60 msec (P < 0.05) immediately and to 400 ± 56 msec (P < 0.01) at 1-week follow-up. The effective refractory period of the AV node prolonged from 282 ± 83 msec to 312 ± 89 msec and to 318 ± 81 msec after 1 week (P < 0.05), respectively.
Conclusion : This study shows a decrease in ventricular response to pacing-induced atrial fibrillation after ablation of the slow pathway in patients with AV nodal reentrant tachycardia. Since the AV nodal conduction properties could be defined, this study supports the hypothesis that the main mechanism of AV nodal modification in chronic atrial fibrillation is caused by ablation of posterior inputs to the AV node.  相似文献   
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During healing following tooth extraction, inflammation and the immune response within the extraction socket are related to bone resorption.

Objective

: We sought to identify how the alloplastic material used for socket preservation affects the immune responses and osteoclastic activity within extraction sockets.

Material and Methods

: Using a porcine model, we extracted teeth and grafted biphasic calcium phosphate into the extraction sockets. We then performed a peptide analysis with samples of gingival tissue from adjacent to the sockets and compared the extraction only (EO) and extraction with socket preservation (SP) groups. We also used real-time polymerase chain reaction (PCR) to evaluate the expression level of immunoglobulins, chemokines and other factors related to osteoclastogenesis. Differences between the groups were analyzed for statistical significance using paired t tests.

Results

: Levels of IgM, IgG and IGL expression were higher in the EO group than in the SP group 1 week post-extraction, as were the levels of CCL3, CCL5, CXCL2, IFN-γ and TNF-α expression (p<0.05). In addition, receptor activator of nuclear factor kappa-B ligand (RANKL) was also significantly upregulated in the EO group (p<0.05), as were IL-1β, IL-6 and IL-8 (p<0.05).

Conclusions

: These results suggest that the beneficial effect of socket preservation can be explained by suppression of immune responses and inflammation.  相似文献   
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BACKGROUND: The mechanisms responsible for an imbalanced cytokine response in atopic diseases are still not understood. While impaired interferon-gamma (IFN-gamma) production may be the result of a pathological T-cell/antigen-presenting cell (APC) interaction, evidence was provided that the T cell itself may have an intrinsic defect to produce IFN-gamma. OBJECTIVE: To clarify whether impaired IFN-gamma production by T cells from patients with atopic dermatitis (AD) represents an intrinsic defect in producing IFN-gamma. METHODS: Effector T cells were generated from CD4+ CD45RA+-naive precursors from patients with AD and healthy control individuals by activation with anti-CD3+ anti-CD28 MoAbs. Following restimulation, IFN-gamma production was measured by ELISA and flow cytometry. RESULTS: IFN-gamma production by atopic T cells was decreased compared with healthy T cells. IL-12 present at priming or high doses of IL-2 during the culture period, even in the absence of IL-12, completely restored IFN-gamma production. Conversion of naive CD45RA+ to CD45R0+ effector cells did not differ between atopic and healthy donors' T cells. CONCLUSION: Impaired IFN-gamma production by T cells from atopic individuals is not the result of an intrinsic, genetically fixed, defect to produce sufficient amounts of IFN-gamma. The data provides evidence that correction of an impaired TH1 response in AD may be successful at the precursor T cell level.  相似文献   
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R JUNG 《Acta oto-laryngologica》1948,36(3-4):199-202
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溯源中医体质学说及其在中医学中应用   总被引:2,自引:2,他引:0       下载免费PDF全文
辨别体质是在中医辨证治疗过程中不可缺少的手段之一。对目前比较公认的中医体质学说的溯源、分型及应用研究的成果进行了简述。  相似文献   
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