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81.
Brucellosis represents a rare cause of neonatal infection. In this article we report a very unusual case of congenital infection due to BRUCELLA MELITENSIS in a term neonate presenting after birth with severe respiratory distress and radiological manifestations (lobar consolidation and diffuse interstitial infiltrations) compatible with pulmonary involvement. The neonate was successfully treated with trimethoprim-sulfamethoxazole, rifampicin, and gentamicin.  相似文献   
82.
We describe a child dependent on parenteral nutrition who developed loss of all conventional central venous catheter insertion sites coupled with very unusual collateralization due to extensive thrombosis of both the superior and inferior vena cava, including the azygos vein. We successfully achieved trans-hepatic anterior access to the infra-diaphragmatic vena cava. Since the success rate for this technique is low due to catheter dislodgement, the procedure was surgically assisted for increased safety and efficacy.  相似文献   
83.

Objectives

The aim of this in vitro study was to assess the effect of toothpastes containing three different sodium fluoride concentrations and a calcium sodium phosphosilicate system, on root dentine demineralization and remineralization.

Methods

During a fourteen-day pH-cycling protocol, pre-softened bovine root dentine specimens were immersed twice daily, before and after the demineralization periods, for 2 min, in the following toothpaste slurries: (a) non-fluoridated (control), (b) 7.5% calcium sodium phosphosilicate, (c) 1450 ppm F, (d) 2800 ppm F, and (e) 5000 ppm F. Subsequently, the slabs were subjected to a fifty-hour acid resistance test. Knoop microhardness at different lesion depths was assessed in specimen cross-sections and KHN values were converted to vol.% mineral. Comparisons between the groups were performed at each lesion depth through ANOVA-based tests and furthermore, regression analysis of the derived statistic of “integrated vol.% mineral loss” was carried out. Also, lesions were evaluated qualitatively using transmission and polarized light microscopy.

Results

The 5000 ppm F toothpaste group, during pH-cycling, presented significantly less total vol.% mineral loss and subsequently exhibited considerably increased surface acid resistance, compared to all the other tested groups. The calcium sodium phosphosilicate toothpaste, during pH-cycling, inhibited demineralization and/or promoted remineralization of the surface layers significantly more effectively than the control group nevertheless, subsequently, the acid resistance of the calcium sodium phosphosilicate dentifrice group was similar to that of the control group. These observations were confirmed by microscopic examination of the lesions.

Conclusions

Under the present experimental conditions, the 5000 ppm F toothpaste, promoted remineralization and inhibited demineralization more effectively, than the other tested toothpastes.  相似文献   
84.
High-affinity extrasynaptic GABA(A) receptors are persistently activated by the low ambient GABA levels that are known to be present in extracellular space. The resulting tonic conductance generates a form of shunting inhibition that is capable of altering cellular and network behavior. It has been suggested that this tonic inhibition will be enhanced by neurosteroids, antiepileptics, and sedative/hypnotic drugs. However, we show that the ability of sedative/hypnotic drugs to enhance tonic inhibition in the mouse cerebellum will critically depend on ambient GABA levels. For example, we show that the intravenous anesthetic propofol enhances tonic inhibition only when ambient GABA levels are <100 nm. More surprisingly, the actions of the sleep-promoting drug 4,5,6,7-tetrahydroisothiazolo-[5,4-c]pyridin-3-ol (THIP) are attenuated at ambient GABA levels of just 20 nm. In contrast, our data suggest that neurosteroid enhancement of tonic inhibition will be greater at high ambient GABA concentrations. We present a model that takes into account realistic estimates of ambient GABA levels and predicted extrasynaptic GABA(A) receptor numbers when considering the ability of sedative/hypnotic drugs to enhance tonic inhibition. These issues will be important when considering drug strategies designed to target extrasynaptic GABA(A) receptors in the treatment of sleep disorders and other neurological conditions.  相似文献   
85.
The aim of this study was to assess the serum concentrations of Clara cell secretory protein (CC16) in association with acute and chronic lung injury in mechanically ventilated preterm neonates. Thirty-five preterm neonates (gestational age [GA] ≤31 weeks) with acute respiratory failure were enrolled. Of these, 23 neonates requiring ventilatory support within 2 h after birth comprised the mechanically ventilated group (MV group), and 12 neonates who were not ventilated made up the nonventilated group (NV group). Serum CC16 was measured (using enzyme-linked immunosorbent assay [ELISA]) within 2 h (T0) and at 72 h (T1) after birth, at day 14 of life (T2) and at 36 weeks postmenstrual age (T3). The median CC16 concentrations were significantly higher in the MV group compared to the NV group at all times. Analysis with respect to differences observed in the group characteristics showed that GA, Apgar score at 5 min and mechanical ventilation were significant covariates of serum CC16 at T0. All neonates in the NV group and 18 cases in the MV group, respectively, survived discharge. Ventilated survivors with later bronchopulmonary dysplasia (BPD; oxygen requirement at T3, n = 7) had significantly higher CC16 at all times compared to nonventilated neonates. Elevated serum CC16 levels at T2 were predictive of BPD development. In conclusion, our results show that serum CC16 increases significantly in preterm neonates ventilated early after birth and remains high in those with later BPD. Further research is needed to validate the usefulness of CC16 as a peripheral blood biomarker of acute and chronic lung injury.  相似文献   
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89.
The likelihood of finding organ-confined untreated prostate cancer (PCa) by pathological examination at the time of radical prostatectomy (RP) is only 50% in patients with clinically organ-confined disease. In addition, tumour is present at the resection margin in approximately 30% of clinical T2 (clinical stage B) cases. The issue of clinical "understaging" and of resection limit positivity have led to the development of novel management practices, including "neoadjuvant" hormonal therapy (NHT). The optimal duration of NHT is unknown. We undertook the present analysis to evaluate the effect of NHT on pathologic stage of PCa and resection limit status in patients with prostate cancer and treated with total androgen ablation either for three or six months before RP. Between January 1996 and February 1998, 259 men with prostate cancer underwent radical retropubic prostatectomy and bilateral pelvic node dissection in the 26 centres participating in the Italian randomised prospective PROSIT study. Whole mount sectioning of the complete RP specimens was adopted in each centre for accurately evaluating the pathologic stage and resection limit status. By February 1998, haematoxylin and eosin stained sections from 155 RP specimens had been received and evaluated by the reviewing pathologist (RM). 64 cases had not been treated with total androgen ablation (e.g. NHT) before RP was performed, whereas 58 and 33 had been treated for three and six months, respectively. 114 patients were clinical stage B whereas 41 were clinical stage C. After three months of total androgen ablation, pathological stage B was more prevalent among patients with clinical B tumours, compared with untreated patients (57% in treated patients vs. 36% in untreated). The percentage of cancers with negative margins was statistically significantly greater in patients treated with neoadjuvant therapy than those treated with immediate surgery alone (69% vs. 42%, respectively). After six months of NHT therapy the proportion of patients with pathological stage B (67% vs. 36%, respectively) and negative margins was greater than after 3 months (92% vs. 42%, respectively). For clinical C tumours, the prevalence of pathological stage B and negative margins in the patients treated for either 3 or 6 months was not as high as in the clinical B tumours, when compared with the untreated group (pathological stage B: 31% and 33% vs. 6% in the clinical C cases, respectively. Negative margins: 56% and 67% vs. 31%, respectively). The initial results of this study suggest that total androgen ablation before RP is beneficial in men with clinical stage B because of the significant pathological downstaging and decrease in the number of positive margins in the RP specimens. These two effects are more pronounced after six months of NHT than after three months of therapy. The same degree of beneficial effects are not observed in clinical C tumours.  相似文献   
90.
Background  TNFα seems to contribute to inflammation and malnutrition in Crohn’s disease (CD) patients. In CD patients, the comparative effects on nutritional status of infliximab and traditional therapy have not yet been determined. The aim of our study was to assess the effects of infliximab as compared with those of standard therapy on nutritional status, disease activity, resting energy expenditure (REE), and food intake in CD children and adolescents. Methods  From September 1999 to September 2005, all CD patients treated with infliximab (group A) were reviewed and matched with CD patients treated with traditional therapy (mesalazine and azathioprine) (group B). Results  Fourteen CD patients from group A and 14 from group B were included; median interval before follow-up investigation was 10 months. Baseline and final values of weight, height, body mass index (BMI), pediatric CD activity index (pCDAI), REE, and food intake were studied. In treated patients, but not in control group, mean baseline weight (kg) and BMI values, 39.7 ± 13.1 and 17.9 ± 3.3, respectively, were significantly lower than their final values 42.6 ± 13.2 and 18.9 ± 3.1, and median pCDAI values 23.5 were significantly higher than their final values 10 (P < 0.05). Significant changes in height, REE, and food intake were not found in either group. Conclusions  In pediatric CD patients, infliximab seems to impact positively on the nutritional status as demonstrated by the improvement in weight and BMI, but not in linear growth; effects on nutritional status seem to be due to amelioration of disease activity, rather than to REE reduction or food intake increase.  相似文献   
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