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The results of panoramic diagnostic microhysteroscopy are reported in 284 patients with sterility or infertility problems. In 33.5% of the patients, microhysteroscopy revealed uterine pathology; in the majority of cases they were pathologies which are unanimously recognized as being causes of sterility, while in others there were pathologies whose role infertilities is still unclear. There was a good correlation between microhysteroscopy and histology in cases of endometrial hyperplasia and of endometritis, whereas in cases of endometrial polyps and functional diagnosis of the endometrium, the correlation was less satisfactory. Although it is not possible at present to draw definite conclusions about the real value and advantages of microhysteroscopy in the diagnosis of female infertility, we are convinced that it is of great use and that it should be at the basis of any investigation involving the infertile woman.  相似文献   
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We studied the effects of cardiac rehabilitation on the sympathovagalcontrol of heart rate variability in 30 patients after a first,uncomplicated myocardial infarction. Twenty-two patients completed8 weeks of endurance training (trained), while eight decidednot to engage in the rehabilitation programme for logisticalreasons, and were taken as untrained controls. Age, site ofinfarction, ejection fraction, ventricular diameter and stresstest duration were similar in the two groups at baseline. Heartrate variability was evaluated 4 weeks after infarction beforestarting rehabilitation, and repeated 8 weeks and one year laterin both trained and untrained patients. Measures of heart ratevariability, obtained from both time- and frequency- domainanalysis of a 15 min ECG recording in resting conditions, wereas follows: mean RR interval and its standard deviation (RRSD),the mean square successive differences (MSSD), the percent ofRR intervals differing >50 ms from the preceding RR (pNTN50),the low and high frequency components of the autoregressivepower spectrum of the RR intervals and their ratio (LF/HF).At baseline, heart rate variability was similar in trained anduntrained patients. In the short term (8 weeks after infarction),training increased RRSD by 25% (P<0·01), MSSD by 69%(P<0·01), pNN50 by 120% (P<0·01), and reducedLF/HF ratio by 30% (P<0·01). The effects persistedafter one year in trained patients. In untrained patients, theautonomic control of heart rate variability did not change 8weeks after myocardial infarction and was only slightly modifiedby time. Thus, exercise training, performed for 8 weeks aftera myocardial infarction, modifies the sympathovagal controlof heart rate variability toward a persistent increase in parasympathetictone, known to be associated with a better prognosis. This maypartly account for the favourable outcome of patients who undergorehabilitation.  相似文献   
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This work deals with the UV spectrophotometric quantitation of a mixture of compounds with overlapped spectra. The mixture spectrum is resolved by use of three computational programs based on different algorithms, namely Multicomponent Analysis (commercial software available from Hewlett-Packard), MULTIC (relying on multiple regression analysis) and SIMPLEX. The results obtained for mixtures of acetylsalicylic acid, acetaminophen and caffeine in commercial analgesic formulations, are compared.  相似文献   
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The effects of various Flustra foliacea metabolites on different types of human neuronal nicotinic acetylcholine receptors (nAChRs) expressed in Xenopus oocytes were investigated. Whereas most of the compounds tested had a small blocking effect, one of them, deformylflustrabromine, selectively increased the current obtained in alpha4beta2 receptors when co-applied with acetylcholine (ACh). The current increase was reversible and concentration-dependent. This potentiating effect was still present at saturating concentrations of acetylcholine, and no changes in single-channel conductance or reversal potential were observed, thus suggesting a modification in the gating of alpha4beta2 receptors. Dwell time analysis of single channel records indicates that the mechanism of action of deformylflustrabromine could be both an increase of the opening rate constant and a decrease of the closing rate constant on alpha4beta2 receptors. Thus, deformylflustrabromine may constitute an excellent starting point for the future development of related agents able to potentiate human neuronal nicotinic receptor function.  相似文献   
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Various studies suggested that inflammation is involved in the pathogenesis of Alzheimer's disease (AD). We investigated cytokine release from LPS-stimulated blood cells of 32 AD patients, with different disease severity, compared to 16 age-related controls. A significant decrease of IL-1beta and IL-6 secretion was observed in severely demented patients; TNF-alpha release was also decreased, but not significantly. By contrast, mild and moderate patients showed a cytokine release similar to controls. IL-1beta, IL-6 and TNF-alpha secretion was negatively correlated with the severity of dementia, quantified by the MMSE. Our data suggest that alterations of the immune profile are associated with AD progression.  相似文献   
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Congenital hypothyroidism results in deafness that is caused by changes in the auditory receptor, including scanty development of the outer hair cells and a lack of synaptogenesis between these cells and the efferent system. although the afferent population is present. The normal efferent innervation of the cochlea originates in the superior olivary complex, arising from efferent neurons belonging to the lateral or to the medial olivocochlear system. In the rat, the former is constituted by neurons located in the lateral superior olivary nucleus, that project to the inner hair cells, while the later originates in the ventral nuclei of the trapezoid body and project to the outer hair cells. The aim of this work is to study the localization, number and morphology of the olivochochlear neurons in congenital hypothyroid animals by means of the injections of the retrograde tracers, either fast blue or cholera toxin, in the cochlea. The mean total number of labeled olivocochlear neurons after injection of fast blue in hypothyroid animals was 1,016, and in control ones was 1,027. Using cholera toxin, the mean total number of labeled olivocochlear neurons was slightly lower: 863 in hypothyroid animals versus 910 in control ones. Although both tracers showed no significant differences between groups, when the somatic area of the labeled olivocochlear neurons is considered, the size of all of the three different population of cells (lateral olivocochlear neurons, medial olivocochlear neurons and shell neurons) was significantly lower in the hypothyroid rats. This is the first study of the olivocochlear neurons in hypothyroid animals. The conclusion from this work is that in hypothyroid rats the labeled olivocochlear neurons are significantly smaller but that there is not any modification in the localization and number of the labeled olivocochlear neurons, suggesting that thyroid hormones are necessary for the neuronal growth. However, most of the medial olivocochlear neurons do not make contact with their target, so their maintenance suggests that the axons are in contact with other structures of the cochlea.  相似文献   
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