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1.
Our group has previously reported significant changes in the incorporation of precursors into glycerophospholipids, particularly phosphatidylserine, in polymorphonuclear cells obtained from the peripheral blood of cluster headache patients, when compared with controls. The potential of these results led to further work using both the previous methodology and a modified isolation technique to obtain polymorphonuclear cells in as pure a state as possible. Neither the new results obtained using the original technique, nor the results with high purity polymorphonuclear cells from controls and cluster headache patients, confirm the marked changes in precursor uptake into glycerophospholipids originally reported.  相似文献   
2.
Propriospinal myoclonus (PSM) is a rare movement disorder characterized by involuntary spinal-generated muscular jerks that spread rostrally and caudally to other spinally innervated muscles. Most patients have no clear etiology, and conventional MRI of the spinal cord is generally normal. Here we report the use of magnetic resonance diffusion tensor imaging (DTI) and fiber tracking to detect tract-specific abnormalities in a patient with propriospinal myoclonus. As the patient had the fragile-X premutation and antithyroid antibodies, spinal cord DTI abnormalities may be related to these conditions. Tract-specific analysis may provide new insights into the pathophysiology of propriospinal myoclonus.  相似文献   
3.
The surface-spreading synaptonemal complex (SC) technique was employed to analyze spermatocytes and oocytes of rainbow trout in order to visualize the process of autosome and sex chromosome synapsis in this species. The structure of lateral elements (LEs) of the SC and the chromosome synapsis process at the stages of leptotene, zygotene and pachytene are described. Comparative analysis of SCs of spermatocytes and oocytes showed a difference in the synaptic process, i.e. in spermatocytes all LEs were synapsed before the appearance of centromeric regions in the biarmed elements, while in the oocytes some fully synapsed LEs, including the centromeric region of the biarmed elements, were found together with fully or partially unsynapsed LEs. In males the sex chromosome synapsis starts only after all autosomes have synapsed. Irregular synapses involving three or four LEs were found in 3.4% of the cells analyzed in mid or late zygotene. Multivalents were found in males and females. Some aspects of initial meiotic development and their implications in rainbow trout cytogenetics, genetics and evolution are discussed.  相似文献   
4.
Immunization of BALB/c mice with an expression genomic library of Toxoplasma gondii induces a Th1-type immune response, with recognition of several T. gondii proteins (21 to 117 kDa) and long-term protective immunity against a lethal challenge. These results support further investigations to achieve a multicomponent anti-T. gondii DNA vaccine.  相似文献   
5.
Characterization of Sm13, a tegumental antigen of Schistosoma mansoni   总被引:2,自引:0,他引:2  
Sm13, a 13-kDa Schistosoma mansoni tegumental antigen, is one of the principal polypeptides recognized by antibodies from mice protectively vaccinated with adult-worm tegumental membranes. To obtain the complete gene encoding Sm13 we subcloned and sequenced a cDNA and a fragment of a genomic clone. The collated sequence contains 1088 nucleotides and represents the full-length open reading frame of the gene, encoding a protein of 104 amino acids with a calculated molecular mass of 11,923 Da, compatible with the native protein identified in the tegumental membranes. The sequence derived from genomic DNA contains a 45-nucleotide intron. The analysis of the predicted protein suggests the presence of both N- and C-terminal hydrophobic membrane-spanning segments, and the coding region contains no homology in the currently available data bases. Additionally, the coding region is preceded by putative CCAAT and TATA boxes that may be involved in the control of expression. Western-blot analysis and indirect immunofluorescence resulted in the identification of a 13-kDa protein (Sm13) in the tegument of adult worms. The present study reveals that Sm13 behaves as an integral membrane protein upon partitioning in Triton X-114 and that it is present in worms of 3 weeks or older but not in schistosomula or miracidia. Moreover, it is also specifically recognized by sera from some schistosomiasis patients in enzyme-linked immunosorbent assay and Western-blot analysis, suggesting that it is immunogenic in human schistosomiasis. Received: 17 February 2000 / Accepted: 22 March 2000  相似文献   
6.
Red foxes served as a biological indicator for the temporal development of environmental contamination with polychlorinated biphenyls (PCB). The concentration of PCB congeners nos. 28, 49, 52, 101, 138, 153, and 180 were analyzed in the body fat of 80 foxes (Canis vulpes) from Germany. The samples were from animals that had been submitted for examination in 1983, 1987, and 1991. Throughout this time period, a reduction was seen in the concentration of the highly chlorinated biphenyls 138, 153, and 180, whereas the concentration of the low-chlorinated congeners PCB nos. 28, 49, and 52 increased. No change in contamination with congener 101 was observed. These results show a trend toward reduction of environmental contamination with highly-chlorinated biphenyls since 1983, while contamination with low-chlorinated congeners is apparently increasing.An interesting observation is the disproportionately higher amount of 2,2,3,4,4,5,5-hepatachlorobiphenyl (PCB 180) over that of 2,2,4,4,5,5-hexachlorobiphenyl (PCB 153) in body-fat samples from all foxes analyzed. This phenomenon was also observed in 10 dogs examined as controls. Based on evidence from other authors of experimental toxicological studies on beagles, it appears that the fox possesses a similar cytochrome P-450 isoenzyme that can degrade 2,4,5-trichloro-substituted aromatic compounds. As a consequence, in canines, PCB 180 which is additionally meta-chloro substituted is accumulated to a greater degree than is PCB 153.This paper contains portions of the doctoral thesis of G. Bachour  相似文献   
7.
Intravenous administration of antibothropic antivenom (BAv) neutralises the systemic effects, but does not efficiently reverse the local symptoms elicited by the Bothrops jararaca venom (BjV). The mechanisms involved in this poor protection have not been clarified. In this work, intravital microscopy studies were carried out to determine the efficacy of different schedules of BAv treatment on local effects evoked by topical application of BjV in the microcirculatory network of the internal spermatic fascia of Wistar rats. Results demonstrated that BAv administration 15 min before, simultaneously with, or 15 min after BjV application did not totally reverse the local symptoms, represented by disturbances of coagulation, development of haemorrhage lesions, vascular permeability increase and increment on leukocyte-endothelium interactions. This lack of effectiveness neither reflects an inadequate amount of specific antibodies in the antivenom against toxins responsible for local effects nor an insufficient dose of circulating BAv during the assays. Administration of fluorescein isothiocyanate (FITC) labelled-BAv showed the dynamics of distribution of the antivenom in the microcirculatory network. Images obtained from prior and simultaneously treated animals showed that the antivenom remains at luminal side of vessels before venom application, and the latency time to antivenom leakage is coincidental to that for local effects evoked by the venom. In addition, images from posterior treatment demonstrated that the intense alterations in the microcirculatory network impair antivenom distribution at the site of injection. Together, our data show that the lack of effectiveness of antivenom therapy is due to impaired and delayed venom and antivenom interaction at the site of injury.  相似文献   
8.
OBJECTIVES: To assess the serious maternal morbidity during pregnancy, delivery and post partum, which led to an hospitalization in a medical or surgical intensive care unit. STUDY DESIGN: A Retrospective study was carried out on a period of ten years, from July 1986 to July 1996, in the University Teaching Hospital of Besan?on. PATIENTS: The criterions of inclusion come from the definition of the serious maternal morbidity decided by the Inserm: any admission of a pregnant woman in a medical or surgical intensive care unit in the 42 days of the post-partum, whatever the term of the pregnancy and the type of the post-partum, extra uterine pregnancy, spontaneous miscarriage and medical or voluntary abortion. METHODS: Forty-six patient's medical file hospitalized in a medical or surgical intensive care unit between July, 1st 1986 and July, 31st 1996, have been studied. RESULTS: The analysis of the cause underline the gravity of the pathologies handled with young patients and initially healthy, the short length of controlled ventilation and hospitalization, the avoidability of great number of transfer in an intensive care unit, and the lack of hospitalization due to anaesthesia. The frequency of hospitalisation in an intensive care unit during and after the pregnancy was estimated at 0.17% of lives births. CONCLUSION: The serious maternal morbidity could be an indicator of the quality of the obstetrics cares which would complete the study of the maternal mortality. The potential gravity of the complication of the pregnancy and the delivery require better care of this patients.  相似文献   
9.
This study was undertaken to examine whether males develop schizophrenia at a younger age than females, and whether temporal socioeconomic change affects the age at onset of schizophrenia. The subjects were 848 ICD-9 schizophrenics who were admitted to Nihon University Hospital, Tokyo, Japan, during the period of 1955-64 (n = 468 (214 males and 254 females), group A) or during the period of 1982-91 (n = 380 (220 males and 160 females). group B). Schizophrenic males showed an earlier age at onset than schizophrenic females. However, the mean age at onset of schizophrenia did not differ significantly between group A and group B. These results indicate that the gender difference in age at onset of schizophrenia has not been influenced by temporal socioeconomic change.  相似文献   
10.
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