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21.
Summary. The association of premature rupture of the membranes (PROM) and ascending infection was investigated in 15 women. Bacteriological, histological and immunofluorescence methods were used to study infection at various levels in the birth canal. In most of the women the membranes as well as the placentae showed heavy bacterial invasion. Bacterial distribution within the membranes showed a choriodecidual preponderance. Ascending infection appears to follow the choriodecidual route and may be a primary pathogenetic event in many instances of PROM. The anaerobe Bacteroides fragilis , which is very infrequently isolated in normal pregnant women, was found in five out of 15 women. Two infants had congenital pneumonia caused by group B streptococci and Haemophilus influenzae respectively. The neonatal outcome with PROM may be influenced by the efficiency of the individual defence mechanisms including the antimicrobial capacity of amniotic fluid.  相似文献   
22.
Strand L, Jenkins A, Grude N, Allum A‐G, Mykland H‐C, Nowrouzian FL, Kristiansen B‐E. Emergence of fluoroquinolone‐resistant clonal group A: clonal analysis of Norwegian and Russian E. coli isolates. APMIS 2010; 118: 571–77. We describe a study of urinary tract and intestinal isolates of Escherichia coli from Norway and Russia using automated ribotyping, single nucleotide polymorphism analysis for clonal group A (CgA) supplemented with phylogrouping, virulence gene profiling and resistance profiling. CgA comprised 19% of the Norwegian UTI isolates from 2001. Two highly multiresistant fluoroquinolone‐resistant CgA isolates were found. Ribotypes clustered into four major and six minor groups (ribogroups). Fluoroquinolone‐resistant isolates and phylogroups A and B1 were associated with ribogroup RA. Ribogroup RB predominated among Russian UTI isolates and was predominantly phylogroup A and depleted in P‐fimbriae. Ribogroup RC predominated among Norwegian UTI isolates and was rich in virulence factors (S‐fimbriae, haemagglutinin and haemolysin) and predominantly phylogroup B2 and D. Ribogroup RG was associated with CgA and predominantly phylogroup D. Ribogroups RD, RE and RF had too few members for statistical analysis. The correlation between ribotype and phylogenetic group was not as strong as reported in other studies.  相似文献   
23.
Because late valve-related complications such as hemolysis and thromboembolic events are considered related to flow disturbances caused by the inserted valve, velocity fields downstream of aortic valve prostheses were studied in pigs. Acute hemodynamic evaluation of size 25-mm porcine and pericardial aortic valve prostheses 1 diameter downstream of the valve ring was performed using dynamic three-dimensional visualization of velocity profiles and spatial distribution of turbulence. Point blood velocity signals obtained with a 1-mm hot-film anemometer needle probe were used to compute Reynolds normal stresses (RNS) by calculation of the turbulent velocity energy of the axial velocity component in the systole. The porcine valves caused a skewed velocity and turbulence profile revealing mean spatial systolic RNS at 70 nm-2 +/- 35 nm-2 (+/- SD). The spatial maximum RNS was 275 +/- 139 nm-2. Corresponding values for the pericardial valves were 20 +/- 11 nm-2 and 72 +/- 46 nm-2. The pericardial valves revealed plug-shaped velocity profiles and turbulent profiles with slightly higher RNS values at the stent posts. From a hemodynamic point of view, these acute studies indicate superiority of the pericardial valves compared to the porcine valves. The turbulent stresses found in this study are of a magnitude that may cause blood corpuscular and endothelial damage.  相似文献   
24.
Abstract – This study measured the flexural and fatigue strengths of root canal posts of different alloy, design, and diameter. Fixed posts were loaded up to a preset force and the number of loadings endured until fracture was recorded at each loading force. The flexural strength was defined as the maximum force a post could endure before fracture when loaded once. The fatigue strength was determined as the maximum force a post could endure when loaded 10000 times. Both modes of strength were found to increase with increasing diameter. Aluminum posts had lower flexural and fatigue strengths than posts of titanium, stainless steel, and a Ag-Pd alloy, all of which had strength values of about the same magnitude. Among the investigated brands, Triax and Radix were stronger than the others at comparable diameters. The high strength of Triax may be explained by the design of the post, whereas a superior alloy may account for the high strength of Radix.  相似文献   
25.
Dipeptidyl peptidase IV (DPPIV) is a transmembrane serine protease which is involved in the process of tumor invasion and development of metastases in human cancers. The aim of this study was to investigate the expression of DPPIV in cancer and stromal cells of both esophageal adenocarcinoma and squamous cell carcinoma (SCC). Tissue material from 159 patients was analyzed using immunohistochemistry. Western blotting was performed on cell lines and fresh frozen tissue sections. Results were compared with clinicopathological features. Evaluation of the immunohistochemical findings revealed significant differences between DPPIV expression in carcinoma cells and stromal cells, depending on the histological tumor type. A significantly higher level of DPPIV was found in adenocarcinomas compared to SCCs while no DPPIV was detected in normal esophageal epithelium. Overexpression of DPPIV in patients with adenocarcinoma was additionally associated with distant metastases. Thus, differences of DPPIV level in esophageal carcinomas compared with normal epithelium showed that esophageal malignancies were associated with an increased amount of cell surface‐bound DPPIV. Radiotherapy in patients had no impact on DPPIV expression in analyzed tissue samples. There was no correlation between DPPIV expression in cancer or stromal cells and survival of the patients.  相似文献   
26.
Abstract – Di- and monomethacrylates hydrolyze to methacrylic acid and the alcohol part at neutral pH catalyzed by an unspecific esterase (hydrolase) and by enzymes in saliva. The rate constants of the enzymatic hydrolysis of various (di)methacrylates increase in the following order: HPMA < BISGMA < LAMA < DECMA < TEGDMA < UEDMA < DEGDMA. Esterase added to aqueous slurries of various powders made of polymerized BISGMA/TEGDMA-mixtures gave rise to liberation of methacrylic acid, presumably deriving from degradation of those of the dimethacrylates only bonded in the matrix by one end of the molecule. It was estimated that a TEGDMA-polymer will be hydrolyzed faster than a BISGMA-polymer. It is proposed that hydrolases in saliva increase the wear rate of composite resin fillings.  相似文献   
27.
Abstract – The amount of methacrylic acid produced by incubation of the dimethacrylate ester TEGDMA in human whole saliva was measured. The conversion rate of TEGDMA was determined in stimulated saliva from dental students and in unstimulated saliva from both dental students and patients. The differences in mean conversion rate measured in the three groups were not statistically significant ( P= 0.346). The mean conversion rate ± SD for all saliva samples was 4.54 ± 3.24 μmol MAA/L. h. The surface of BISGMA/TEGDMA-polymer specimens treated with porcine liver esterase in activities equivalent to those found in human saliva exhibited a lower Wallace microhardness than the surface of untreated specimens. Polymer specimens incubated in human saliva exhibited a similar reduction in the microhardness. The results demonstrated that enzymes in human saliva are capable of softening the surface of dimethaerylate polymers presumably by inducing a hydrolysis of methacrylate ester bonds. The mechanical removal of a surface layer softened by hydrolases will expose a new surface layer to enzymatic attack. The enzymatic softening may thus contribute to the in vivo wear of composite restorations.  相似文献   
28.
Radiofrequeucy ablation of the atrioventricular conduction system (ACS) has become an estoblished theTapy for patients with drug refroctory atrial fibrillation. We observed eight patients with hemodynamic deterioration ofteT radiofrequency oblotion of the otTioventTicular conduction system. As we found hemodynamic deterioration related to worsening mitral regurgitation, we compared the clinical history, eiectrophysiologicai, ond echocardiographic dato from the patients with hemodynamic deteriorotion and worsening mitral regurgitation (group 1) to those without hemodynamic deterioration and stable mitral regurgitation after the procedure (group 2). Eight out of 108 patients (7.4%) undergoing ablation of the ACS deteriorated hemodynamically with acute pulmonary edema in three and congestive heart failure in five patients occurring at a mean of 3 and 8 weeks, respectively, after the procedure. Three of these patients were referred for mitral valve surgery. Two patients underwent ablation using a left-sided approach. A right-sided approach was used in five patients. In one patient, a left- and right-sided approach was used. Compared to group 2 patients, group 1 patients had significantly higher left ventricular end-diastolic diameters (64 ± 6 mm vs 56 ± 9 mm) at baseline despite similar fractional shortening (32%± Il% vs 34%± 13%), left ventricular end-systolic diameters (43 ± 9 mm vs36 ± 7 mm) and degree of mitral regurgitation (1.4 ± 1.1 vs 1.4 ±0.7) on echocardiographic analysis. Thus, hemodynamic deterioration together with progression of mitral regurgitation is a potential complication of ablation of the ACS (up to 7.4%). Patients with high left ventricular end-diastolic diameters ond moderate mitral regurgitation at baseline seem prone to this complication.  相似文献   
29.
Predicting New‐Onset AF. Background: Atrial fibrillation (AF) increases morbidity and mortality in patients with previous myocardial infarction and left ventricular systolic dysfunction. The purpose of this study was to identify patients with a high risk for new‐onset AF in this population using invasive and noninvasive electrophysiological tests. Methods: The study included 271 patients from the Cardiac Arrhythmias and RIsk Stratification after Myocardial InfArction (CARISMA) study with an acute myocardial infarction (AMI) and left ventricular ejection fraction ≤40% without previous AF at enrollment. Within 21 days after the AMI, an implantable loop recorder was inserted and used to diagnose AF over the 2‐year study duration. The following tests were performed: heart rate variability (HRV) and turbulence (HRT) analyses from repeated 24‐hour Holter recordings, 2‐dimensional (2D)‐echocardiograms, exercise test, and programmed electrophysiologic stimulation. Results: A total of 101 patients (37%) developed AF during the study. Predictive measures included several indexes of HRV including reduced low‐frequency (LF) power from spectral HRV analysis (adjusted HR = 1.6, P = 0.034), HRT slope ≤2.5 (HR = 1.6, P = 0.032) and Detrended Fluctuation Analysis (DFA1) from HRV analysis (HR = 1.8, P = 0.011); all are measures of cardiac autonomic nervous system dysfunction. Combined with age >60 years, low values for LF, HRT slope, and DFA1 provided a powerful risk score for prediction of new‐onset AF (1–2 points: HR = 4.3, P = 0.001, 3–4 points: HR = 7.0, P < 0.001). Conclusion: Abnormal HRV and HRT parameters, which are associated with disturbances in the cardiac autonomic regulation, are associated with increased risk of new‐onset AF independently of conventional clinical risk variables. (J Cardiovasc Electrophysiol, Vol. 21, pp. 983‐990, September 2010)  相似文献   
30.
PROBLEM: Menstrual disorders, reduced fertility and sexual problems seem to be more frequent in women with epilepsy than in the general population. Most investigations concerning menstrual disturbances in epilepsy patients, however, are small and based on selected materials. We therefore wanted to investigate the frequency of menstrual disturbances in a large, unselected population of epilepsy patients. METHODS: A retrospective, questionnaire study of a cohort of female outpatients, aged 18-45 was conducted. Each patient chose a close female friend who served as control, to optimise matching regarding age and lifestyle. RESULTS: Answers were received from 265 patients and 142 controls. Menstrual disturbances were more frequent in patients with epilepsy (48.0%) than in controls (30.7%) (P=0.004). Menstrual disturbances were more frequent in patients on polytherapy versus monotherapy (P=0.049) and more frequent in patients with high seizure frequency (>5seizures/year) compared to patients with a lower seizure frequency or those seizure free (P=0.006). The frequency of menstrual disturbances was higher in patients on valproate compared to carbamazepine monotherapy (P=0.045). CONCLUSION: This investigation confirms that women with epilepsy have an increased frequency of menstrual disturbances compared to women without epilepsy. In women with high seizure frequency and in those on polytherapy, the frequency of menstrual disturbances are further increased. The highest frequency of menstrual disturbances occurred in women using valproate.  相似文献   
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