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31.
The pathogenicity of Blastocystis hominis is extensively debated in the medical literature. Therefore, we did a prevalence study to investigate the association between the presence of several intestinal parasites and gastrointestinal symptoms in diverse patient cohorts. The study population consisted of 1216 adults, including immunocompromised patients, institutionalized psychiatric or elder subjects, immigrants from developing countries, travellers to developing tropical countries and controls. Several variables for each risk group were considered. Stools specimens, collected in triplicate, were processed by the same technicians. Clinical data about each subject were provided by standardized questionnaires. The presence of gastrointestinal symptoms were related to the presence of any parasite. In addition, on the basis of microbiological results, five subgroups of subjects were evaluated. The results showed a high prevalence of parasites in all the risk groups. Immunocompromised status, recent arrival from developing countries and the presence of behavioural aberrations were significantly related to presence of parasites. B. hominis was the parasite most frequently detected in each studied group. B. hominis showed a significant correlation with gastrointestinal symptoms only when detected in the group including subjects with a severe immunodepression. Immunodepression seems to be a factor of primary importance of the pathogenic role of B. hominis.  相似文献   
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L-leucine, an essential amino acid, is one of the most popular ingredients in dietary supplements. To investigate a possibility of its embryo-fetal toxicity in rats, 11- to 12-week old dams were orally administered an aqueous solution of L-leucine at doses of 300 or 1000 mg/kg body weight on gestational days 7-17. Body weight and feed intake was evaluated throughout the whole course of pregnancy (days 0-20). L-Leucine did not influence body weight, but at a dose of 1000 mg/kg, slightly enhanced feed intake on days 14 and 18 of pregnancy. Caesarean section (day 20) revealed no influences on the litter size and weight of live-born fetuses, the number of corpora lutea, implantation index or the quality of placenta, and the minor increase in feed intake was considered irrelevant to the pregnancy outcomes. Fetuses were evaluated in a battery of external, visceral and skeletal examinations. No effects of L-leucine on gender ratio and external abnormalities, and no significant treatment-related variations in visceral and skeletal pathologies were observed. These results suggested that L-leucine, administered orally during organogenesis at doses up to 1000 mg/kg body weight, did not affect the outcome of pregnancy and did not cause fetotoxicity in rats.  相似文献   
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IntroductionThere is growing interest in the relationship between fibromyalgia and processes related to food, such as food intolerances. In fact, different associations have been described between the control of dietary habits and the improvement of the different symptoms of fibromyalgia.Material and methodsWe collected the results of applying a specific test of histamine release related to the diet of patients with fibromyalgia, and evaluated the changes in terms of the symptoms usually described by the patients. A total of 84 patients who met the established criteria were recruited; 40 of them underwent the exclusion diet for a period of 6 months, while the remaining ones continued with their usual dietary habits. All patients were instructed not to modify any other parameter during the study, such as medication, exercise, or other complementary treatments. The parameters studied were as follows: the Fibromyalgia Impact Questionnaire (FIQ), the Gastrointestinal Symptoms Rating Scale (GSRS), the pain Visual Analogue Scale (VAS), as well as the patients’ body weight was controlled.ResultsThere was a significant improvement (p < 0.05) in the group of patients who underwent the exclusion diet in assesment by GSRS and in total in total body weight. There were no differences compared to the rest of the patients in terms of VAS and FIQ.ConclusionsDiet modification in patients with fibromyalgia by specific histamine relase test improves certain clinical parameters related to the symptoms of the digestive sphere, compared to the control group. Our work opens a possible way of non-pharmacological treatment to improve some symptoms of this very prevalent disease.  相似文献   
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Several hepatitis B virus (HBV)-related factors, including the viral load, genotype, and genomic mutations, have been linked to the development of liver diseases. Therefore, in this study we aimed to investigate the influence of HBV genetic variability during acute and chronic infection phases. A real-time nested PCR was used to detect HBV DNA in all samples (acute, n = 22; chronic, n = 49). All samples were sequenced for phylogenetic and mutation analyses. Genotype A, sub-genotype A1, was the most common genotype in the study population. A total of 190 mutations were found in the pre-S/S gene area and the acute profile revealed a greater number of nucleotide mutations (p < 0.05). However, both profiles contained nucleotide mutations linked to immune escape and an increased risk of hepatocellular carcinomas (acute, A7T; chronic, A7Q). Furthermore, 17 amino acid substitutions were identified in the viral polymerase region, including the drug resistance mutations lamivudine and entecavir (rtL180M), with statistically significant differences between the mutant and wild type strains. Owing to the natural occurrence of these mutations, it is important to screen for resistance mutations before beginning therapy.  相似文献   
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OBJECTIVE: To establish leukocyte count and leukocyte differential percentiles in normal uncomplicated pregnancy. STUDY DESIGN: This retrospective longitudinal study was performed in an outpatient facility for routine antenatal care. The study population comprised of 726 healthy women from the 5th to the 41st week of pregnancy. Altogether, there were 1749 complete blood count evaluations, of which 481 were in the 1st trimester, 687 in the 2nd trimester and 581 in the 3rd trimester. The total and differential leukocyte counts were determined by an automated cell counter. RESULTS: The leukocyte and neutrophil counts gradually and significantly increased form the 1st to the 3rd trimester. The monocyte count increase became significant only during the 3rd trimester. The eosinophil count did not significantly change throughout pregnancy. The basophil count significantly decreased during the 2nd trimester and returned to 1st trimester values during the 3rd trimester. CONCLUSION: In this study, we provide total and differential leukocyte counts' mean+/-S.D., minimal and maximal values, and the 3rd, 5th, 10th, 50th, 90th, 95th, and 99th percentiles for entire pregnancy and for each trimester separately. These reference values should prove useful for diagnostic and research purposes.  相似文献   
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Introduction of Doppler ultrasound in obstetrical practice has changed both management and understanding of several diseases that put at risk women and them fetuses. To establish necessary basics and correctly apply this technique, this review will focus in physical principles, acquisition methods, consistency, and safety issues of Doppler ultrasound, in order to improve precision, accuracy and interpretation of this methodology.  相似文献   
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Zusammenfassung Die Berichte über die reizhusten-bekämpfende Wirkung des Giftlattichs (Lactuca virosa) und seiner Zubereitung, die wir in der Literatur des Mittelalters und auch später vorfinden, lassen sich im Tierversuch bestätigen und quantitativ verfolgen. Die Wirkung ist bei Gewichts-vergleich der Wirkung des Milchsaftes etwa 5oomal schwächer als beim Morphin. Dieses Verhältnis wird aber günstiger, wenn die Droge fraktioniert gegeben wird, weil ihre Wirkung protrahierter ist, und erreicht dann nur noch eine etwa 50mal schwächere Wirkung. Diese Zahlenangaben gelten nur für das Gewicht, nicht für die therapeutische Breite. Im Gegenteil werden trotz der entsprechend höheren Dosierung die Gefahren von Nebenwirkungen geringer sein, besonders die Gefahr der Sucht fehlen. Daher füllt es eine Lücke im Arzneischatz. Allerdings ist nicht zu erwarten, daß die ganze Tiefe der Morphinwirkung je erreicht werden kann, weshalb die Opiate bei schwerstem Reizhusten wohl nicht ersetzt werden können. Man kann beim Vergleich feststellen, daß etwa die Gesamtwirkung der Droge repräsentiert wird durch den Bitterstoff Lactucin, der offenbar auch der Repräsentant der sedativen Wirkung ist.  相似文献   
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