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91.
92.
The aim of our study was to examine the effects of hormone replacement on the size of the uterus and the development or increase of myomatas. Fifty perimenopausal women were included in the study (53.8 ± 5.0 years). Patients received a substitution therapy composed of a combination of 4 mg estradiolvalerate and 200 mg prasteronenantate (Gynodian® Depot cartridges) given as a muscular injection in 6–10 week intervals (mean 7 weeks ± 4 days). Prior to the onset of therapy with Gynodian® and after a period of 12 months (± 13 days) vaginosonography was performed. Measurements taken were length, thickness, height of endometrium, size of ovaries and of myomas. Data obtained were correlated with baseline findings. Within 1 year, significant increases in uterus length from 73.4 mm to 88.2 mm, in uterus thickness from 33.9 mm to 43.5 mm and in endometrium height from 4.1 mm to 6.7 mm were observed (median values). There was an increase in both the number (from 2.2 to 3.5) and the size of the myomatas (29.4–35.0 nm diameter). A statistical analysis conducted by means of the Wilcoxon matched pairs signed-rank sum test showed P < 0.001. No significant change occurred in the size of the ovaries. Our study shows that hormone substitution may have an impact on uterus growth and that therefore vaginosonographical monitoring can be recommended.  相似文献   
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94.
Benzodiazepines can regulate neoplastic growth and immune response through specific peripheral benzodiazepine receptors. We investigated the presence of peripheral and classic central benzodiazepine receptors as well as diazepam-binding inhibitor, an endogenous ligand of both types of receptors, in different human cerebral tumors. Peripheral benzodiazepine receptors were present in all the tumor types studied, whereas central benzodiazepine receptors and diazepam-binding inhibitor were detectable in astrocytomas and glioblastomas and undetectable in meningiomas, neurinomas, and metastases. The role of diazepam-binding inhibitor and of the different benzodiazepine receptors in neoplastic cells is still to be defined.  相似文献   
95.
Acetylcholine and tachykinins act as co-transmitters along excitatory pathways at different gut levels. Since cholinergic pathways are involved in maintaining gastric tone during fasting, our aim was to study the possible role of tachykininergic pathways in modulating canine gastric tone and compliance in vivo by using selective tachykinin receptor antagonists. In four fasting, conscious dogs, we characterized the pressure-volume relationship in the proximal stomach by using a barostat. We increased the pressure of the intragastric bag by 2 mmHg increments every 3 min, starting from a baseline value of 2 up to 12 mmHg. Drug effects were investigated by studying pressure-volume relationships before and 15 min after intravenous (i.v.) administration of SR140333, SR48968, or SR142801 (respectively, NK (1)-, NK (2)-, and NK (3)-receptor antagonist, each at the dose of 1 mg kg (-1)) or atropine (100 microg kg (-1)). Pressure-volume curves were fitted by nonlinear regression analysis. Before drug administration, the curve that best fitted the pressure-volume relationship was exponential. SR140333, SR48968 and SR142801 did not affect baseline gastric tone or the gastric pressure-volume curve at any distension level. At a distending pressure of 6 mmHg, the Delta volumes obtained after administration of SR140333, SR48968 or SR142801 vs control were 65 +/- 28, 27 +/- 26, 14 +/- 20 ml, respectively. The same was true even when all three antagonists were administered together to achieve simultaneous blockade of all three tachykinin receptor subtypes. Atropine increased baseline gastric volume (Delta volume = 237 +/- 15 ml; P< 0.01) and significantly (P< 0.0001) shifted the pressure-volume curve to the left. After atropine, a linear equation best fitted the pressure-volume curve. We conclude that tachykininergic pathways are not involved in modulating canine gastric tone and compliance during fasting, whereas cholinergic pathways play a major role not only in maintaining gastric tone, but also in modulating the compliance of the proximal stomach to a distending stimulus.  相似文献   
96.
We investigated CSF levels of diazepam-binding inhibitor (DBI), a recently discovered neuropeptide that allosterically modulates GABAergic transmission, in various neurodegenerative disorders with dementia (28 patients with Parkinson's disease, 10 with Alzheimer's disease, 7 with Huntington's chorea). We applied a battery of neuropsychological tests to determine the degree of dementia and to exclude the presence of mood alterations. CSF DBI levels were elevated in parkinsonian subjects with dementia and in patients with Alzheimer's disease, but decreased in Huntington's chorea patients. We hypothesize that modifications of CSF DBI levels may be related to a functional or structural alteration of the GABAergic system.  相似文献   
97.
A new technique of umbilicoplasty in neonates who underwent primary omphalocele repair is described and illustrated. The procedure resulted in a nearly-normal appearance of the umbilicus. Accepted: 6 August 1998  相似文献   
98.
The aim of this review is to evaluate the impact of sleep on breast cancer risk. Given the supposed protective role played by melatonin in breast cancer, it is interesting to study the effect of sleep, which is the moment of melatonin synthesis. Articles were extracted from the PUBMED database between 2000 and 2012 with the following keywords “sleep duration”, “sleep quality”, “breast cancer risk” and “melatonin”. In total, 10 articles were selected. Most prospective cohort studies found a decrease in the risk of breast cancer varying from 38 to 72% for “long sleepers”. Furthermore, a meta-analysis of the studies assessing the link between breast cancer risk and urinary concentration of 6-sulfatoxy-melatonin (6MT), which is melatonin's main metabolite, found a 34% decrease for patients with the highest 6MT concentration. Even though other studies are necessary to confirm these results, it seems already adequate to detect sleep disorders and to try to treat them.  相似文献   
99.
Group B Streptococcus (GBS) is the leading cause of neonatal infections in industrialized countries. Intrapartum antibiotic prophylaxis (IAP) given to colonized parturients is a key step for the prevention of neonatal early-onset infection. We compared the performances of Xpert® GBS polymerase chain reaction (PCR) (Cepheid, Sunnyvale, CA, USA) as a point-of-care system in labor wards to standard culture for intrapartum GBS detection. Pregnant women with a GBS-positive antenatal screening were prospectively included. A vaginal double swab was collected at the time of delivery for point-of-care Xpert® GBS PCR and GBS culture. A total of 565 pregnant women were included. Valid Xpert® GBS results were obtained for 488 (86.4%) women on the first attempt. Repeat testing improved the PCR success to 516 (91.3%) women. Among the 305 women positive for GBS by culture at delivery, only 238 (78.0%) were positive by Xpert® GBS PCR, cycle thresholds being correlated to culture quantification. Among 260 women negative for GBS culture, 56 (21.5%) were positive by Xpert® GBS PCR, including 50 where IAP was initiated before vaginal sampling. Overall, among the 565 women with GBS antenatal positive culture, only 335 (59.3%) were still positive at delivery whatever the technique used, resulting in unnecessary IAP for 40% of them. This large cohort study comparing intrapartum to antepartum GBS detection provides evidence that (i) Xpert® GBS PCR might be a valuable solution for intrapartum GBS detection compared to culture-based strategies and (ii) laboratory training of non-specialized staff is mandatory to reach the performances required for point-of-care tests.  相似文献   
100.
Background  Intravenous iron is a critical component of anaemia management. However, currently available preparations have been associated with the release of free iron, a promoter of bacterial growth and oxidative stress.
Materials and methods  We determined the molecular weight, dialysability and capacity for free iron release of ferumoxytol, a semi-synthetic carbohydrate-coated superparamagnetic iron oxide nanoparticle. Ferumoxytol was compared with three intravenous iron preparations in clinical use: iron dextran (low molecular weight), sodium ferric gluconate and iron sucrose. Intravenous iron preparations were also incubated in rat, and pooled human sera (at concentrations of 600 μM and 42 μg mL−1 respectively) from healthy subjects.
Results  The molecular weight of ferumoxytol was 731 kDa. The relative order of molecular weight was as follows: ferumoxytol > iron dextran > iron sucrose > sodium ferric gluconate. The least ultrafilterable iron was observed with ferumoxytol and the most with ferric gluconate. The least dialysable free iron was observed with ferumoxytol and the most with ferric gluconate. Incubation of intravenous iron preparations in rat or pooled human sera demonstrated minimal free iron release with ferumoxytol. The order of catalytic iron release as detected by the bleomycin detectable iron assay was as follows: ferumoxytol < iron dextran < iron sucrose < ferric gluconate. A similar trend was observed for the in vivo serum concentration of free iron in rats.
Conclusions  In vitro observations from these experiments suggest that ferumoxytol has a favourable profile in terms of tendency to release free iron, in comparison with currently available intravenous iron preparations.  相似文献   
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