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991.
Vegetarians may have subtle nutritional deficiencies which have been related to the occurrence of an unrecognized malabsorption syndrome. The excess phytate content in cereals, nuts, legumes and oilseeds which represent the mainstay of their food intake, seems to play a central role in the pathogenesis of this malabsorption syndrome as an inverse relationship has been shown to link the phytate content of the diet with the intestinal absorption of trace minerals and proteins. We postulate that manipulating the endogenous digestive microflora of subjects on a vegetarian diet through administering probiotic lactic bacteria would represent an innovative tool to counteract the occurrence of the malabsorption syndrome dependent on the high phytate content of their diet. Even though there are no data about the composition of endogenous digestive microflora in subjects on a vegetarian diet, we expect that probiotic lactobacilli can interact with or affect distinct yet interrelated components within the intestinal milieu, such as epithelial cells, enteric flora, and/or mucosal immune cells. This would ultimately translate into the correction of the unregulated mechanisms implicated in the altered intestinal absorption of trace metals and proteins commonly seen in vegetarians. Clinical experience with probiotic therapy of patients with inflammatory bowel disease fully agrees with this view. One additional point of interest is that probiotic lactobacilli, and other species of the endogenous digestive microflora as well, are an important source of the enzyme phytase which catalyses the release of phosphate from phytate and hydrolyses the complexes formed by phytate and metal ions or other cations, rendering them more soluble ultimately improving and facilitating their intestinal absorption. The regular intake of probiotic preparation, may represent a cheap and safe tool in order to convert a diet with a low potential for bioavailability of trace minerals and proteins, such as the vegetarian diet, into a diet with a high bioavailability potential. The benefit of such an approach would not be restricted to vegetarians.  相似文献   
992.
We studied the presence of Natural antibodies in plasma samples from individual birds from selected chicken lines at young and old age. Binding, specificity, and relative affinity to various antigens were determined in plasma from non-immunized female chickens at 5 weeks of age, and in plasma obtained from the same chickens one year later using indirect two-step ELISA. Birds were from three different lines. The lines were divergently selected for either high (H line) or low (L line) antibody titers to Sheep Red Blood Cells at 5 weeks of age, next to a random bred control (C line). Binding of plasma immunoglobulins (Ig) from all three lines was found with chicken-egg-white protein (CEP), ovalbumin (OVA), myoglobin (MYO), thyroglobulin (THYRO), keyhole limpet hemocyanin (KLH), bovine serum albumin (BSA), and transferrin (TRANS). Significantly higher binding to most antigens was found with plasma Ig from adult birds from the H line as compared to plasma Ig from the L line, whereas binding of plasma Ig from C-line birds was in between or similar to the H or L line, respectively. Binding of Ig to all antigens in all three lines was significantly higher in plasma obtained at one year of age as compared to plasma obtained at 5 weeks of age. A competitive ELISA with homologous and heterologous antigens was used for determining specificity of the antigen-binding antibodies. Nai;ve plasma samples were characterized by a broad binding to all antigens tested. Inhibition of binding to specific antigens was possible with a broad range of heterologous antigens, but highest competition of binding was obtained with homologous antigen. Both linear regression analysis of serial dilutions of the plasma Ig binding the antigens, as well as competitive ELISA with homologous antigen indicated that plasma Ig from the H line and plasma Ig from the L line had similar affinity characteristics to the antigens tested with the exception of OVA and KLH. Pooled non-immune plasma from H line birds bound to CEP, OVA, THYRO, TRANS, MYO, KLH, and salt-precipitated extracts and supernatants of extracts from chicken heart, spleen, liver, brain, bursa, thymus, and kidney, respectively, as determined by Western blotting. The increasing presence of antibodies in nai;ve chicken plasma binding heterologous and homologous (tissue) antigens indicates the presence of Natural antibodies in poultry. Apart from age, increasing levels of Natural antibodies may be related with the genetically based magnitude of specific antibody levels in the chicken lines studied.  相似文献   
993.
Abnormalities in the long arm of chromosome 7 are a frequent chromosomal aberration in myeloid disorders. Most studies have focused on the analysis of del(7q), demonstrating the presence of several minimal deleted regions in 7q22 approximately q31. By contrast, few studies in myeloid disorders have been devoted to the analysis of translocations, either balanced or unbalanced, involving 7q. In this study, we used fluorescence in situ hybridization (FISH) to characterize the 7q31.3 approximately q34 region (markers D7S480-D7S2227) in patients with deletion or translocation of 7q. A total of 910 cases of myeloid disorders were studied by conventional cytogenetics. Fifty-eight (6%) patients had structural aberrations of 7q. FISH studies were carried out in the 27 patients with involvement of 7q31 approximately q34: 14 cases had an acute myelogenous leukemia and 13 cases had a myelodysplastic syndrome. FISH analysis revealed the existence of high complexity in the 7q31.3 approximately q34 region in patients with unbalanced translocations. No breakpoints in 7q31.3 approximately q34 were found in the cases with deletion or balanced translocation. Nevertheless, studies of unbalanced translocations showed several breakpoints in markers D7S480-D7S2227, which delineate a commonly altered region. The complexity of 7q rearrangements suggests that a synergy of different genetic factors, rather than the alteration of a single tumor suppressor gene, could be involved in the pathogenesis of del(7q) in myeloid disorders.  相似文献   
994.
BACKGROUND: Hymenoptera venom hypersensitivity is an epidemiologically important problem. The only effective treatment in the management of venom-allergic patients with a history of generalized reactions to insect sting is specific immunotherapy. OBJECTIVE: To demonstrate safety and effectiveness of a modified ultrarush desensitization protocol in venom-allergic patients. METHODS: Fifty-seven patients with Hymenoptera venom allergy underwent a specific 1-day ultrarush desensitization by the subcutaneous route, reaching the cumulative dose of 101.1 microg in 2.5 hours. The maintenance dose (100 microg) was administered after 15 days and thereafter once a month. Patients were followed up for a year. Antihistamines were withheld for 15 days before and during desensitization to not underestimate the incidence of adverse effects. RESULTS: All patients but I completed the ultrarush desensitization. (This patient discontinued the treatment because of a hypertensive crisis not related to the desensitization.) The treatment caused a rapid variation of immunological parameters (IgE, IgG4) since the 15th day. After the desensitization, skin prick test results became negative in 15 patients (27%, decrease of 3.5 log), whereas they decreased in 14 patients (25%, decrease of 1 log). Sixty-four percent showed no adverse effects. Only 7% had a mild systemic reaction. CONCLUSIONS: Ultrarush desensitization is an effective and safe therapy in the management of patients with Hymenoptera venom allergy. In fact, it provides a faster tolerance, without significant differences regarding incidence of severe adverse effects, compared with traditional and rush protocols. It can be adopted for all patients, even children and teenagers.  相似文献   
995.
A cytolytic protein named Coelomic Cytolytic Factor-1 (CCF-1) was isolated from the coelomic fluid of the earthworm Eisenia foetida foetida. Despite the absence of any gene homology, CCF-1 showed functional analogy with the mammalian cytokine tumour necrosis factor (TNF), particularly based on similar lectin-like activity. Indeed, both CCF-1 and TNF recognise N,N'-diacetylchitobiose and exert lytic activity on African Trypanosoma brucei brucei. In this report, we show that South-American Trypanosoma cruzi trypomastigotes, but not epimastigotes, were lysed by earthworm coelomic fluid or purified CCF-1. However, T. cruzi was less susceptible to lysis than T. brucei brucei. This lytic effect of coelomic fluid and CCF-1 on T. cruzi trypomastigotes was partially inhibited in the presence of anti-CCF-1 monoclonal antibody, antibody neutralising the lectin-like activity of TNF or N,N'-diacetylchitobiose. In contrast, this lytic effect was completely inhibited when using T. b. brucei. In addition, T. cruzi components, upon recognition by CCF-1 in E. f. foetida coelomic fluid, triggered the prophenoloxidase cascade, an invertebrate defence mechanism. These results further extend the functional analogies of CCF-1 and TNF, suggesting that both molecules share a similar lectin-like activity that has been conserved as an innate recognition mechanism in invertebrates and vertebrates. They also establish a link between stercorarian (T. cruzi) and salivarian (T. brucei) trypanosomatids having divergent phylogenetic origins and patterns of evolution, but possessing closely related cell surface sugar moieties.  相似文献   
996.
997.
998.
AIM: To evaluate the safety of BufferGel (ReProtect LLC, Baltimore, MD), a spermicidal microbicide that acidifies semen and maintains the protective acidity of the vagina, in a high-dose tolerance trial. METHODS: HIV/STD negative, sexually abstinent, and sexually active women in India, Thailand, Malawi, and Zimbabwe were asked to insert one applicator ( approximately 5 ml) of BufferGel vaginally twice per day for 14 days. Sexually active women agreed to have sex (while using BufferGel and nonlubricated condoms) at least twice per week. RESULTS: In total, 98 women (30 sexually abstinent and 68 sexually active) were enrolled. Overall compliance with product use was 93%. Epithelial abnormalities detected by pelvic examination or colposcopy were uncommon (8 cases in 271 examinations). Irritation was reported by approximately one quarter of the women (0.58 events per woman-week) but was generally mild and of short duration. The prevalence of bacterial vaginosis (BV) fell significantly, from 30% at enrollment to 6% at one week, and 7% at two weeks of BufferGel use. Thirty-two women acquired microscopically detectable yeast during BufferGel exposure, but only 3 developed symptomatic vaginitis. CONCLUSION: BufferGel appears to be safe and well tolerated by the cervicovaginal epithelium. Its effect on BV and yeasts merits further study.  相似文献   
999.
1000.
Abstract

The stethoscope is a major symbol of modern medicine. It is used for diagnosis of different conditions and enables physicians to listen to internal body sounds. Electrocardiography was only introduced in medicine in the beginning of the twentieth century. Today measuring heart’s electrical activity is also fundamental cardiac diseases diagnosis. Although performed with independent devices, requiring physician and patient presence in the same physical space, in combination they enhance cardiovascular assessment. In this paper, a digital stethoscope encapsulation was designed, adding new functionality to this advanced medical device. Today wired and wireless communications enable different medical devices to share data and information, over long distances. Using low-cost hardware technologies, the encapsulation will add the ability to acquire and transmit via Bluetooth the Electrocardiographic activity, determined in the same cardiac focus and synchronised with the Phonocardiographic sound recordings. Several encapsulation concepts were developed and prototyped using 3D printing. They were easily fitted to the digital stethoscope and tested in a hospital environment for ergonomics, acoustic and electric signals acquisition. The best concept was chosen with the help of a physician’s opinion and the final prototype performance was very satisfactory.  相似文献   
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