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The rate of local recurrence (LR) has been 20-40% after resective surgery for rectal cancer by the traditional - Miles or Dixon - operative technics. The authors performed curative resection in 358 patients with rectal cancer in a 10 year period (01.01.1990 - 31.12.2000) in the Surgical Department of Szeged University. Since 01.01.1996 the authors changed this type of surgery for the Heald technics (total mesorectal excision - TME - with sharp dissection, using the UltraCision device) for the surgical treatment of middle or lower third rectal cancer. To compare the results of the two procedures, the authors analysed their material in two periods: Period I: 01.01.1991 - 31.12.1992: 62 patients operated on with the traditional operative technics; LR 15% within 2 years after surgery. Period II: 01.01.1997 - 31.12.1998: 78 patients operated on with the Heald technics (TME with sharp dissection); LR 6.4% within 2 years after surgery. Based on their results, the authors found that the modern operative technics by Heald, used in the second period of the study, was a relevant factor decreasing LR from 15% to 6.4%, while the gender, age of the patients, ratio of the abdominoperineal extirpation versus anterior resection (APRE/AR) and the free margin of more than 3 cm proved to be irrelevant.  相似文献   
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BACKGROUND: The Hungarian Case-Control Surveillance of Congenital Abnormalities was established in 1980. This article describes how the Hungarian Case-Control Surveillance of Congenital Abnormalities was first organized and is currently maintained. The baseline statistics are provided and potential venues of postmarketing surveillance of drug teratogenicity and other public health tasks and research are proposed. METHODS: Cases with congenital abnormalities and patient controls with Down syndrome were selected from the Hungarian Congenital Abnormality Registry. Population controls without congenital abnormalities were selected from the National Birth Registry on the basis of three matching criteria: sex, week of birth, and district of parent's residence. Three sources of information concerning drug exposures, maternal disorders, and pregnancy complications, among others, were used: (1) prospective and medically recorded data from antenatal care logbooks and discharge summaries; (2) retrospective maternal self-reported data obtained with a structured questionnaire in all the three study groups; and (3) data collected by regional nurse in house visits to nonrespondent cases and patient controls. Twenty-five congenital abnormality groups were evaluated. During the 17-year period of data collection, 22,843 cases, 38,151 population controls, and 834 patient controls were incorporated into the data set, constituting the largest population-based case-control data set of congenital abnormalities to date. RESULTS: Demographic features of pregnant women and informative offspring are presented along with the distribution of 25 main groups of congenital abnormalities. CONCLUSIONS: This system is appropriate for postmarketing the surveillance of drug teratogenicity, for the improvement of congenital abnormality diagnosis, to get informed consent, to have a communication with parents and to provide material for research.  相似文献   
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Sonic hedgehog (Shh) signaling patterns many vertebrate tissues. shh mutations dramatically affect mouse ventral forebrain and floor plate but produce minor defects in zebrafish. Zebrafish have two mammalian Shh orthologs, sonic hedgehog and tiggy-winkle hedgehog, and another gene, echidna hedgehog, that could have overlapping functions. To examine the role of Hedgehog signaling in zebrafish, we have characterized slow muscle omitted (smu) mutants. We show that smu encodes a zebrafish ortholog of Smoothened that transduces Hedgehog signals. Zebrafish smoothened is expressed maternally and zygotically and supports specification of motoneurons, pituitary cells and ventral forebrain. We propose that smoothened is required for induction of lateral floor plate and a subpopulation of hypothalamic cells and for maintenance of medial floor plate and hypothalamic cells.  相似文献   
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Glutathione (GSH), a general antioxidant and detoxifying compound, is the most abundant thiol-containing peptide in the central nervous system. It has been earlier shown to regulate the functions of glutamate receptors and to possess specific binding sites in both neurons and glial cells. The possible involvement of disulfide bonds, cysteinyl, arginyl, lysyl, glutamyl, and aspartyl residues in the binding of tritiated GSH to specific sites in pig cerebral cortical synaptic membranes was now studied after covalent modification of membrane proteins. Treatment of synaptic membranes with the thiol-modifying reagents 5,5-dithio-bis(2-nitrobenzoate) (DTNB) and 4,4-dithiodipyridine (DDP) dramatically enhanced the binding of [3H]GSH in a dose-dependent manner. Dithiothreitol (DTT) alone reduced the binding, but pretreatment of the membranes with DTT potentiated the enhancing effect of DTNB. On the other hand, when the modification with DTNB was followed by treatment with DTT, the enhancement by DTNB was completely reversed. N-ethylmaleimide, a thiol alkylating agent, and phenylisothiocyanate, a thiol- and amino-group modifying compound, reduced the binding, and their effects were additive. The guanidino-modifying agent phenylglyoxal reduced the binding but the carboxyl-modifying reagent 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide had no significant effect. The results indicate that cysteinyl side chains and disulfide bonds are essential in the binding of GSH to membrane proteins and that arginyl and lysyl side chains may also be directly involved in this process.  相似文献   
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The present study was undertaken to characterize the oocyst morphology, host specificity, organ location, virulence, and sequences of the small subunit ribosomal RNA, 70-kDa heat shock protein, and oocyst wall protein genes of Cryptosporidium baileyi, and to compare this strain with other Cryptosporidium species. This study also aims to serve as a model for polyphasic (phenetic and genetic) characterization of Cryptosporidium species and strains. On the basis of these results, further genetic and phenetic characterization of an avian isolate is needed if the difference between the length or width, or both, of oocysts of an isolate and of C. baileyi is > or = 10% or if the difference between the oocyst shape index of the isolate and of C. baileyi is > or = 3% (or both). The isolate is infectious for mammals or lower vertebrates, or the host range is narrow, i.e., infectious only for some bird species; after oral or intratracheal inoculation, the parasites are not located in the cloaca and in the bursa of Fabricius or the respiratory tract; clinical disease or weight gain reduction can be observed after oral inoculation; the genetic distance for the examined gene between C. baileyi and the isolate is similar in magnitude to that observed between most closely related Cryptosporidium species.  相似文献   
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The fungal revolution taking place in otorhinology inspired us to study the frequency of occurrence of fungi in the nasal mucus of chronic rhinosinusitis (CRS) patients (with or without polyposis) in order to evaluate the incidence of eosinophilic fungal sinusitis in CRS patients. Ninety-six samples were examined from patients with CRS. In 74 cases mucus was collected non-invasively, and in 22 cases during operation. The Gram-stained direct smears of all samples were also evaluated. Bacteria and fungi colonizing in the mucus were detected by culturing method. The control group consisted of 50 healthy volunteers. Typical aerobic pathogenic bacteria could be isolated from 34 patients. Fifty-seven aerobic bacteria were isolated, i.e. 1.6 bacteria/positive patient with a maximum of 3 different bacteria/sample. The most frequently isolated bacteria were Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Streptococcus pneumoniae, and Haemophilus influenzae. Yeasts and moulds could be detected from 79 patients (83%): Candida albicans, Candida spp., Aspergillus spp., Cladosporium spp, and Penicillium spp. were isolated most frequently. Altogether 237 yeasts and moulds were isolated, i.e. 3.0 different fungi/positive patient, with a maximum of 5 different fungi/sample. In the control group aerobic pathogens were not isolated, only apathogenic species. Fungi were isolated from 22 healthy patients (44%). These data indicate that fungi are frequently involved in the aetiology of CRS. IgE-medicated hypersensitivity to fungal allergens could not be proven in our patients.  相似文献   
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