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51.
52.
With the aid of live-bait traps, we studied the risk that Copernicia prunifera palm trees, present in both periurban and rural localities of an endemic Brazilian northeast Chagas disease region, represent to domestic infestation by Rhodnius nasutus. In this area, this important vector has been encountered harboring and transmitting Trypanosoma cruzi, the etiologic agent of the American trypanosomiasis, to mammals, possibly including humans. Results indicate that this bug colonizes C. prunifera palm trees of both regions, mainly in dry seasons, and is infected with high levels of T. cruzi. Although more triatomines were captured in rural areas, proportionally the number of infected bugs from peri-urban regions was much higher. Herein we address the epidemiologic implications and challenge for the Brazilian health authorities to control the disease in this region, where the native palm trees have been largely destroyed causing a severe disturbance in the environmental equilibrium.  相似文献   
53.
This paper reports on three cases of patients with an apparently normal heart admitted for sustained monomorphic ventricular tachycardia. The only abnormal finding showed in the electrocardiogram (ECG) in sinus rhythm that exhibited an entity associated with incomplete right bundle-branch block and persistent ST-segment elevation. The ECG entity was variable and disappeared transiently. Spontaneous ventricular tachycardia in one patient was inducible by programmed stimulation. There was no underlying heart disease. The origin of the ventricular tachycardia in one patient was located by pace mapping in the left ventricle at the left ventricular basal septum. The follow-up (from 6 months up to 6 years) demonstrated a good prognosis. This particular ECG entity associated with monomorphic ventricular tachycardia could have been missed because of the variations in the ECG in sinus rhythm and was associated with a favorable prognosis.  相似文献   
54.
Background: To the best of the authors’ knowledge, there is no systematic review of the potential association between periodontitis and gestational diabetes mellitus (GDM) in the current literature. The aim of the present systematic review and meta‐analysis is to search for scientific evidence regarding the association between periodontitis and GDM. Methods: The present study was conducted in accordance with the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) statement and registered (CRD2014010728) with PROSPERO (International prospective register for systematic reviews, University of York, York, UK). A search was conducted in three electronic databases without restrictions regarding language or date of publication. From 190 studies selected, 15 underwent full‐text analysis. Eight studies were eligible (five cross‐sectional and three case‐control studies), and seven were entered in the meta‐analysis. Meta‐analysis was performed with tests for sensitivity and statistical heterogeneity. Summary effect measures were calculated by odds ratio (OR) and 95% confidence interval (CI). Results: There was a significant association between periodontitis and GDM in the meta‐analyses of four cross‐sectional studies (OR 1.67, 95% CI 1.20 to 2.32) and two case‐control studies (OR 2.66, 95% CI 1.52 to 4.65). However, sensitivity tests for case‐control studies showed a lack of consistency in data; when including one case‐control study, the significance was null (meta‐analysis of three case‐control studies: OR 1.69, 95% CI 0.68 to 4.21). Conclusions: There was substantial clinical, methodologic, and statistical heterogeneity among the studies. The scientific evidence cannot affirm a positive association between periodontitis and GDM. Future studies with different designs in distinct populations should be conducted to investigate this association.  相似文献   
55.

Objective

To evaluate the efficacy and safety of abciximab following acute myocardial infarction (AMI) treated with percutaneous coronary interventions.

Methods

A meta-analysis of randomized controlled trials of platelet glycoprotein IIb/IIIa inhibitor abciximab as adjunctive therapy to percutaneous coronary interventions for AMI was performed. Main outcomes measured were: (1) mortality, (2) reinfarction, (3) target vessel revascularization (TVR), (4) major cardiac events (MACE) that were a composite endpoint of death, reinfarction, and TVR, and (5) major bleeding.

Results

Six trials randomized 3755 patients who were followed for a mean of 5.5 months. Compared with the control, abciximab significantly reduced mortality (OR 0.70, 95% CI 0.50-0.97), TVR (0.79, 95% CI 0.65-0.96) and MACE (0.76, 95% CI 0.65-0.90). Reduction on TVR and MACE was confirmed in stent patients, but not in balloon angioplasty patients. Abciximab was associated with an increased risk of major bleeding (OR 1.39, 95% CI 1.03-1.87), but bleeding was observed only with a 100U/kg heparin bolus followed by a maintenance infusion (OR 1.89, 95% CI 1.10-3.28) and not with a bolus of 70U/kg (OR 1.22, 95% CI 0.85-1.73).

Conclusions

Abciximab, as adjunctive therapy to percutaneous coronary interventions, reduces mortality, TVR and MACE following AMI. The reduction of clinical outcomes occurs with stent implantation but not with balloon angioplasty. A 70U/kg heparin bolus must be used to avoid major bleeding.  相似文献   
56.
57.
BACKGROUND: Low-renin (volume-dependent) hypertension represents 25-30% of all cases of primary hypertension. Endothelial dysfunction and vascular remodeling are associated with hypertension but their relevance to volume-dependent hypertension (VDH) is not yet known. To evaluate this, flow-mediated dilation (FMD) of the brachial artery and the carotid intima-media thickness in the distal common carotid artery were measured and compared between renin-dependent mild-hypertensive patients (RDH) and controls. METHOD AND RESULTS: The study group comprised 40 mild-hypertensive patients and 25 controls. Plasma renin activity (PRA), plasma aldosterone concentration, angiotensin II and nitrite/nitrate plasma levels were measured. According to PRA, subjects were classified as VDH (<0.6 ng . ml (-1) . h(-1)), or RDH (>0.6 ng . ml(-1) . h (-1)). Vascular function was evaluated by FMD before and after reactive hyperemia (RH) and glyceryl-trinitrate (GTN) administration. FMD in response to RH and GTN in the VDH group when compared with RDH group was 10.2+/-2.8% vs 13.3+/-3.6% (p=0.01); and 16.0+/-3.5% vs 19.9+/-4.5% (p=0.01), respectively. CONCLUSION: This study showed impaired FMD and reduced GTN response in mildly hypertensive patients with low-renin plasma levels.  相似文献   
58.
Left ventricular dysfunction in Chagas' disease is common but can be difficult to detect. We investigated whether measurement of plasma brain natriuretic peptide (BNP) could identify patients with left ventricular dysfunction who need further investigation or treatment. Among patients with an abnormal electrocardiogram or chest radiograph, a BNP concentration of 60.7 pmol/L or higher has a sensitivity and positive predictive value of 80%, and specificity and negative predictive value of 97%. Measurement of plasma BNP concentration could be a useful method to screen patients with Chagas' disease.  相似文献   
59.
Immunohistochemistry (IHC) has been employed in the differential diagnosis of tumors.ObjectiveTo assess the use of IHC in cases of head and neck tumor.MethodThis is a retrospective study of the cases included in the Cancer Registry of the institution.ResultsIHC was used in 76 (11%) of 704 pathology tests. Most cases were carcinomas (85.80%), and 83.66% of them were squamous cell carcinomas. All tests were done with diagnostic purposes. The most frequently used antibodies were 34BE12 (37.18%), AE1/AE3 (35.9%), 35BH11 (28.21%), CD45 (25.64%), CD20 (24.36%), CD30 (24.36%), CK7 (23.08%) and CD3 (23.08%).ConclusionsIHC was used in 10.67% of the head and neck tumor cases submitted to pathology testing, mostly for carcinoma (5.26%). In the determination of squamous cell carcinoma, IHC accounted for 18.42% of all tumors.  相似文献   
60.
In the present study, 20 new compounds having 3-[2-(5-aryl-1,3,4-oxadiazol-2-yl) imino-4-thiazolidinon-5-ylidene]-5-substituted/nonsubstituted 1H-indole-2-one (I-XII) and 3-[2-(4-carbethoxymethylthiazol-2-yl)imino-4-thiazoldinon-5-ylidenel-5-substituted/nonsubstituted IH-indole-2-one (XIII-XX) systems were synthesized. The structures were confirmed by spectral methods (UV, IR, 1H-NMR, 13C-NMR, 13C-DEPT (135), electron impact mass spectrometry) and elemental analysis. All compounds were tested for in vitro antimicrobial activity against Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Salmonella typhi, Shigella flexneri, Proteus mirabilis ATCC 14153, Candida albicans ATCC 10231, Microsporum gypseum (NCPF-580), Microsporum canis, Trichophyton mentagrophytes and Trichophyton rubrum and some of them were found to be active. Especially, compound I was more active than cefuroxime sodium (CAS 56238-63-2) which was used as a standard, and the activity of compound XII was close to that of cefuroxime sodium against Staphylococcus epidermidis ATCC 12228. Primary screening for antituberculous activity was conducted at 6.25 microg/ml against Mycobacterium tuberculosis H37Rv in BACTEC 12B medium using the BACTEC 460 radiometric system. The anticonvulsant activities of selected prototoype compounds (I, IV-VI, VIII, XI, XIII, XVI-XVIII) administered at doses of 50-200 mg/kg (i.p.) were evaluated using the pentetrazol test (PTZ) in mice.  相似文献   
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