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11.
M. G. Bradbury M. Henderson J. T. Brocklebank H. A. Simmonds 《Pediatric nephrology (Berlin, Germany)》1995,9(4):476-477
A 9-month-old child with the skeletal abnormalities of Fuhrmann's syndrome presented with acute renal failure secondary to bilateral renal calculi. Hereditary xanthinuria was shown to be the underlying metabolic defect. Treatment with allopurinol was unsuccessful at reducing the xanthine excretion. 相似文献
12.
Ducklings on a problem farm which showed persistent and unacceptably high mortality yielded a larger range and greater number of viruses than did ducklings from a second flock, in which mortality was of a power and acceptable level. Reoviruses were the viruses most frequently isolated from young birds from both farms, but for longer at the problem site. ELAs (Embryo Lethal Agents), named since they caused high mortality in chick embryos, but could not otherwise be characterized, were recovered frequently and throughout the growth cycle of the problem flock, but not at all in the other flock. Lentogenic Newcastle disease virus was detected at all ages on the problem farm but less often than ELAs. The faeces of birds on the problem farm yielded rota-like viruses, corona-like viruses and adeno-like viruses, and on the farm with normal mortality, Egg Drop Syndrome-76 virus and adenovirus. Detection techniques included culture on chick embryos and chick embryo liver cells, and electron microscopy (EM). Inoculation of whole eggs was particularly valuable and more successful than cell culture for virus recovery. EM was most useful for direct examination of faecal preparations and confirmation of the viral type. 相似文献
13.
New chromogenic identification and detection of Staphylococcus aureus and methicillin-resistant S. aureus 下载免费PDF全文
Merlino J Leroi M Bradbury R Veal D Harbour C 《Journal of clinical microbiology》2000,38(6):2378-2380
This paper describes a new chromogenic plate medium, CHROMagar Staph aureus (CHROMagar, Paris, France), for the identification of Staphylococcus aureus on the basis of colony pigmentation. The abilities of CHROMagar Staph aureus, thermostable nuclease (DNase), and mannitol salt agar (MSA) to identify S. aureus isolates (n = 114) and discriminate between S. aureus and coagulase-negative staphylococci (CoNS; n = 22) were compared. CHROMagar Staph aureus proved to be more sensitive and specific than DNase and MSA, allowing a reliable, simple, and rapid method for the identification of S. aureus isolates. All CoNS encountered in this study with the exception of S. chromogenes could be easily differentiated from S. aureus on this medium. The supplementation with 4 microgram of oxacillin or methicillin per ml allowed simple identification of methicillin resistance in hospital-acquired S. aureus strains which show multiple-drug resistance profiles. Community-acquired methicillin-resistant S. aureus strains showing non-multi-drug resistance profiles require further evaluation on this new chromogenic medium. Methicillin or oxacillin resistance of all S. aureus isolates was confirmed by the detection of penicillin-binding protein 2a, encoded by the mecA gene, using the latex slide agglutination MRSA-Screen test (PBP 2' Test, DR900M; Oxoid). 相似文献
14.
This paper describes attempts to isolate and characterize glycosaminoglycan (GAG)-binding molecules on the surface of lymphocytes and lymphoma cell lines and relate their expression to splenic and lymph node homing capacity. Initial binding studies with radiolabelled GAG and rosetting studies with GAG-coupled erythrocytes revealed that there are receptors on lymphocytes for the major classes of GAG (i.e. hyaluronic acid, chrondroitin sulfates, heparin), but lymphocytes bind heparin much more avidly than other GAG species. Analysis of the binding of solubilized radiolabelled cell-surface molecules to immobilized GAG revealed cell-type specific expression of GAG-binding molecules. Thus, each of four lymphoma cell lines tested gave a characteristic pattern of GAG-binding molecules, some molecules being unique to a particular cell line and others being shared by some of the lines. Similarly, splenocytes expressed at least 10 distinct GAG-binding molecules with molecular weights (MW) ranging from 10,000 to 100,000, whereas thymocytes expressed additional GAG-binding proteins of 190,000 and 250,000 MW. Furthermore, splenocytes differed from thymocytes by possessing a unique family of cell-surface molecules which reacted with each GAG. Immunoprecipitation studies demonstrated that the GAG-binding molecules on splenocytes did not correspond to any of the cell-surface antigens tested, notably the cell adhesion molecules MEL-14, CD11/CD18 and CD44, although CD8 bound weakly to heparin. Four lymphoma cell lines with well-characterized migration properties were examined for GAG-binding molecules which may control lymphocyte migration. It was found that no one GAG-binding protein could be correlated with the entry of cells into a particular lymphoid organ. Nevertheless, the role of GAG-binding molecules in the subsequent positioning of lymphocytes within lymphoid organs requires further investigation. 相似文献
15.
Hydrosalpinges adversely affect markers of endometrial receptivity 总被引:22,自引:10,他引:22
Meyer WR; Castelbaum AJ; Somkuti S; Sagoskin AW; Doyle M; Harris JE; Lessey BA 《Human reproduction (Oxford, England)》1997,12(7):1393-1398
While in-vitro fertilization (IVF) was initially developed in women with
tubal factor infertility, recent clinical studies have suggested that the
presence of hydrosalpinges lowers implantation and pregnancy rates. We
postulated that these hydrosalpinges cause impaired endometrial
receptivity. A total of 103 women with hydrosalpinges were prospectively
evaluated, and compared with 55 infertile and 44 fertile controls. All
women had endometrial biopsies during the window of implantation, analysed
by conventional histological criteria, and also stained for three integrin
markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha
vbeta3). Women with hydrosalpinges (cases) expressed significantly less of
the alpha vbeta3 integrin compared with controls. There was no difference
in expression of alpha1beta1 or alpha4beta1 among groups. A significantly
greater number of cases had out of phase histology and missing alpha vbeta3
(type I defects) and absent integrin expression despite normal histological
maturation (type II) defects, compared with controls. Of 20 women with
impaired endometrial receptivity who were also biopsied after hydrosalpinx
surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven
percent of type I and 57% of type II defects were corrected
postoperatively. Using markers of endometrial receptivity, this study
demonstrates that inflammatory hydrosalpinges have an adverse effect on
endometrial receptivity, which in some cases may be overcome by surgical
treatment of the hydrosalpinx.
相似文献
16.
17.
Proliferation of ovarian stromal cells is a common phenomenon in peri- and post-menopausal ovaries. It is generally assumed to be secondary to the rise in circulating gonadotrophins at the menopause, though the process by which it occurs is poorly understood. This study aimed to examine the effect of menopausal levels of pituitary gonadotrophins on the growth of primary cultures of ovarian stroma. A culture system was developed using primary explants of ovarian stroma on a collagen substrate. The effect of follicle stimulating hormone (FSH; 10(-5) g/l) and luteinizing hormone (LH; 10(-5) g/l) on the proliferation of cultures derived from the cortices and medullae of ten ovaries was evaluated using a dual radiothymidine labelling technique. FSH was stimulatory to cortical cultures from 9/10 ovaries and medullary cultures from 7/10 ovaries, while LH was stimulatory to cortical cultures from 6/9 ovaries and medullary cultures from 5/10 ovaries. The responsiveness of the cultures did not correlate with the degree of hyperplasia in vivo. This study demonstrates that pituitary gonadotrophins may modulate the growth of stromal cells in culture, and thus may play a role in the process whereby stromal proliferation occurs in peri- and post-menopausal ovaries. 相似文献
18.
Following preliminary experiments to determine suitable methods for studying mycoplasma survival, suspensions of Mycoplasma gallisepticum (four strains), Mycoplasma synoviae (two strains) or Mycoplasma iowae (two strains) were seeded onto replicate samples of cotton, rubber, straw, shavings, timber, food, feathers and human hair. The organisms were also seeded onto human skin, ear and nasal mucosa. All samples were cultured for viability after 4, 8, 12 and 24 h, and then daily up to 6 days. The identity of recovered mycoplasmas was confirmed by indirect immunofluorescence. All three Mycoplasma species survived for the longest time on feathers with M. gallisepticum surviving between 2 and 4 days and M. synoviae 2 to 3 days. The type strain of M. iowae remained viable for 5 days on feathers, while the field strain was still viable at the end of the 6-day experiment. This strain also survived for at least 6 days on human hair and several other materials. M. gallisepticum survived on human hair up to 3 days and one recent field isolate also survived in the nose for 24 h. Survival times of the organisms were generally less on other materials although M. gallisepticum could be isolated from straw, cotton and rubber samples after 2 days. 相似文献
19.
A 51 year old man presented in 1969 with slowly progressive cerebellar ataxia of unknown origin. He was admitted to hospital aged 68 after a fall, and a ruptured spleen was removed at laparotomy. Histological analysis of the spleen suggested Niemann-Pick disease, which was subsequently confirmed. He deteriorated and died of bronchopneumonia shortly afterwards: subdural haemorrhage with storage material in neurones was found at necropsy. This late onset case of Niemann-Pick disease with neurovisceral storage is unusual and may represent a variant. 相似文献
20.
Pathogenicity and cytadherence of Mycoplasma imitans in chicken and duck embryo tracheal organ cultures. 下载免费PDF全文
Two strains of the avian organism Mycoplasma imitans were examined for pathogenicity and cytadherence in chicken and duck embryo tracheal organ cultures, and a virulent strain of the related pathogen Mycoplasma gallisepticum was included for comparison. All consistently cause ciliostasis in tracheal explants from both hosts, and examination of infected tissues by immunofluorescence and transmission electron microscopy demonstrated that M. imitans proliferated on the epithelial surface and adhered to the respiratory epithelium by means of its terminal tip structure in the same manner as M. gallisepticum. These observations endorse the striking phenotypic similarities between M. imitans and M. gallisepticum and suggest that M. imitans may have pathogenic potential in vivo. 相似文献