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排序方式: 共有501条查询结果,搜索用时 31 毫秒
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A comparison of Skirrow's, Butzler's, Blaser's, Campy-BAP and Preston media for Campylobacter spp was made using human, animal and environmental specimens. Butzler's medium gave the lowest isolation rate and Preston medium, which was the most selective, the highest isolation rate. Enrichment culture using Preston enrichment broth gave a higher isolation rate than direct plating onto Preston medium. 相似文献
5.
Pfeifer JD Ashley Hill D Ramos CV Wippold FJ II Dehner LP 《Archives of pathology & laboratory medicine》2000,124(6):898-901
A 77-year-old woman with neurofibromatosis type 1 presented with ill-fitting dentures due to intraoral extension of a right temporal fossa mass. Computed tomographic scanning demonstrated that the masticator space mass bowed the zygomatic arch and remodeled the lateral orbit and maxillary sinus walls, findings that were consistent with the clinical diagnosis of a neurofibroma with possible malignant transformation. However, light microscopic, immunohistochemical, and ultrastructural examination of tissue from an incisional biopsy specimen were diagnostic of meningioma. This case illustrates that the clinicopathologic differential diagnosis of an enlarging mass in patient with neurofibromatosis should include sporadic, unrelated neoplasms as well as tumors known to be associated with the syndrome. 相似文献
6.
Frataxin is reduced in Friedreich ataxia patients and is associated with mitochondrial membranes 总被引:17,自引:8,他引:17
Campuzano V; Montermini L; Lutz Y; Cova L; Hindelang C; Jiralerspong S; Trottier Y; Kish SJ; Faucheux B; Trouillas P; Authier FJ; Durr A; Mandel JL; Vescovi A; Pandolfo M; Koenig M 《Human molecular genetics》1997,6(11):1771-1780
Friedreich ataxia is a progressive neurodegenerative disorder caused by
loss of function mutations in the frataxin gene. In order to unravel
frataxin function we developed monoclonal antibodies raised against
different regions of the protein. These antibodies detect a processed 18
kDa protein in various human and mouse tissues and cell lines that is
severely reduced in Friedreich ataxia patients. By immunocytofluorescence
and immunocytoelectron microscopy we show that frataxin is located in
mitochondria, associated with the mitochondrial membranes and crests.
Analysis of cellular localization of various truncated forms of frataxin
expressed in cultured cells and evidence of removal of an N-terminal
epitope during protein maturation demonstrated that the mitochondrial
targetting sequence is encoded by the first 20 amino acids. Given the
shared clinical features between Friedreich ataxia, vitamin E deficiency
and some mitochondriopathies, our data suggest that a reduction in frataxin
results in oxidative damage.
相似文献
7.
Francisco J. Salguero Pedro J. Sánchez-Cordón Alejandro Núñez José C. Gómez-Villamandos 《Avian pathology》2002,31(2):133-140
Duck virus enteritis is an acute contagious viral disease affecting birds of the order Anseriformes (ducks, geese and swans). The disease agent is a member of the Herpesviridae family (Anatidae herpes virus 1). A group of Anseriformes waterfowl from a Nature Reserve and Centre for the Recovery of Endangered Species in Spain suffered an outbreak of the disease, affecting adults, young and newborns. Other non-Anseriformes waterfowl such as coots, from the family Rallidae, order Gruiformes, were also affected. Histopathological and ultrastructural findings confirmed the viral infection. The present study provides evidence that birds different from the order Anseriformes can be affected, suggesting that the virus has the ability to infest other non-Anseriformes waterfows. 相似文献
8.
Dithiothreitol prevents age-associated decrease in oocyte/conceptus viability in vitro 总被引:2,自引:0,他引:2
The present study was designed to ascertain whether the negative effects on
reproductive potential of post-ovulatory ageing in vitro of oocytes can be
prevented by antioxidant therapy. Mouse metaphase II (MII) oocytes were
aged in vitro for 12 h prior to insemination in the presence of varying
concentrations of L-ascorbic acid, 6-methoxy-
2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox), L-cystine
dihydrochloride, ethylenediaminetetraacetic acid (EDTA), beta-
mercaptoethanol and DL-dithiothreitol (DTT). In-vitro ageing of oocytes was
associated with lower fertilization rate, higher proportion of concepti
exhibiting cellular fragmentation at 24 h post-insemination and lower
percentage of concepti reaching the blastocyst stage. Ascorbic acid, Trolox
and EDTA had no effect on cellular fragmentation or potential of oocytes
for development. However, the probability of an oocyte reaching the
blastocyst stage was decreased (P < or = or = 0.05) in oocytes incubated
in the presence of L-cystine (50 and 500 microM) and beta-mercaptoethanol
(5, 50 and 500 microM) when compared to control aged oocytes.
Age-associated cellular fragmentation at 24 h post-insemination was
partially prevented (P < or = 0.05) by incubating oocytes in the
presence of beta-mercaptoethanol (500 microM). DTT (50 and 500 microM)
increased (P < or = 0.05) fertilization rate and number of cells at 81 h
post-insemination to levels similar to those exhibited by control oocytes.
Furthermore, both age-associated fragmentation at 24 h post-insemination (P
< or = 0.05) and decreased potential of oocytes for development to the
blastocyst stage (P < or = 0.05) were prevented, at least in part, by
culturing oocytes in the presence of DTT (50 microM). Although the
mechanism by which DTT exerts its beneficial effects on aged oocytes
remains to be elucidated, it may protect oocytes by preventing oxidation of
free thiol groups and/or altering a redox-independent signalling pathway
that mediates cellular fragmentation and death.
相似文献
9.
Núñez A Gómez-Villamandos JC Sánchez-Cordón PJ Fernández de Marco M Pedrera M Salguero FJ Carrasco L 《Journal of comparative pathology》2005,133(1):23-32
Fourteen pigs were inoculated with the 'Alfort 187' strain of classical swine fever (CSF) virus and killed in pairs at 2, 4, 7, 9, 11, 14 or 17 days post-inoculation for histopathological, ultrastructural and immunohistochemical examination. For the latter method, the antibodies used were those against viral antigen Gp55, porcine myeloid marker SWC3, IL-1alpha, IL-6, TNF-alpha and Factor VIII-related antigen. Activation and increase in the number of hepatic macrophages was observed following viral detection in liver, as well as an increase in IL-1alpha and IL-6 production, mainly by Kupffer cells. Maximum detection of viral antigen was observed in the middle stage of the experiment coinciding with overexpression of the three cytokines studied, with IL-6 production by interstitial macrophages prominent at the end. Additionally, the labelling of platelets for Factor VIII-related antigen and the ultrastructural study of the sinusoids revealed activation and aggregation of thrombocytes close to Kupffer cells at the beginning of the infection. The liver seems to play a prominent role in the origin of the thrombocytopenia that occurs in CSF and contributes to the overexpression of proinflammatory cytokines considered responsible for the disorders observed during the course of the disease. 相似文献
10.
Y chromosome microdeletions, in azoospermic or near-azoospermic subjects, are located in the AZFc (DAZ) subregion 总被引:9,自引:2,他引:9
Submicroscopic deletions of the Y chromosome and polymorphisms of the
androgen receptor (AR) gene in the X chromosome have been observed in men
with defective spermatogenesis. To further define the subregions/genes in
the Y chromosome causing male infertility and its relationship to
polymorphisms of the AR polyglutamine tract, we screened the genomic DNA of
202 subfertile males and 101 healthy fertile controls of predominantly
Chinese ethnic origin. Y microdeletions were examined with 16
sequence-tagged site (STS) probes, including the RBM and DAZ genes,
spanning the AZFb and AZFc subregions of Yq11, and related to the size of
trinucleotide repeat encoding the AR polyglutamine tract. Y microdeletions
were detected and confirmed in three out of 44 (6.8%) of azoospermic and
three out of 86 (3.5%) severely oligozoospermic patients. No deletions were
detected in any of the patients with sperm counts of >0.5 x 10(6)/ml,
nor in any of the 101 fertile controls. All six affected patients had
almost contiguous Y microdeletions spanning the entire AZFc region
including the DAZ gene. The AZFb region, containing the RBM1 gene, was
intact in five of the six subjects. Y deletions were not found in those
with long AR polyglutamine tracts. Our study, the first in a Chinese
population, suggest a cause and effect relationship between Y
microdeletions in the AZFc region (possibly DAZ), and azoospermia or
near-azoospermia. Y microdeletions and long AR polyglutamine tracts appear
to be independent contributors to male infertility.
相似文献