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排序方式: 共有1008条查询结果,搜索用时 15 毫秒
91.
M Schmitt-Egenolf TH Eiermann WH Boehncke M St?nder W Sterry 《Canadian Metallurgical Quarterly》1996,106(4):711-714
To further evaluate the nature of the HLA association with psoriasis, HLA haplotypes of 60 patients with type 1 (early onset, positive family history) and 30 patients with type II (late onset, no family history) psoriasis were investigated by polymerase chain reaction sequence-specific oligonucleotide hybridization (HLA class II) and serology (HLA class I). Ethnically matched blood donors (146) served as controls. In type I, but not type II psoriasis, the Caucasian HLA extended haplotype (EH) Cw6-B57-DRB1*0701-DQA1*0201-DQB1*0303 named according to the B allele EH-57.1 was highly significantly overrepresented (p cor= 0.00021). This particular EH was present in 35% of type I psoriatics but only 2% of controls. EH-57.1+ individuals therefore carry a 26 times higher risk of developing type I psoriasis than individuals who are EH-57.1-negative Further analysis of individual HLA alleles revealed that within EH-57.1, HLA class I antigens (Cw6-B57) were associated to a much higher extent with type I psoriasis than the HLA class II alleles (DRB1*0701-DQA1*0201-DQB1* 0303). Pedigree analysis of three multiply affected families over three generations revealed a cosegregation of disease with EH-57.1. These results strongly suggest that a gene for familial psoriasis is associated with the class I side of the extended haplotype Cw6-B57-DRB1*0701-DQA1*0201-DQB1*0303. 相似文献
92.
BACKGROUND: This is a retrospective study to evaluate the incidence of heterotopic ossification (HO) in cemented and uncemented femoral neck fractures treated with Bateman bipolar hemiarthroplasty. METHODS: From October 1985 to July 1990, there were 451 cases of displaced intracapsular fractures of the femoral neck treated with Bateman bipolar hemiarthroplasty (261 uncemented vs 190 cemented) at the Veterans General Hospital-Taipei. RESULTS: After an average follow-up of 46 months, there was more HO in the cemented group than in the uncemented group (p = 0.014, chi-squared test). The average surgical time was approximately 20 minutes longer and the average blood loss was approximately 160 ml more in the cemented Bateman bipolar hemiarthroplasty group. CONCLUSIONS: HO formation is more common in cemented Bateman bipolar hemiarthroplasty than in the uncemented procedure. The incidence of HO is not related to age or sex. 相似文献
93.
MG Beconi-Barker RD Roof L Millerioux FM Kausche TH Vidmar EB Smith JK Callahan VL Hubbard GA Smith TJ Gilbertson 《Canadian Metallurgical Quarterly》1995,673(2):231-244
2- and 4-Nitrophenyl beta-D-xylopyranosides (4 and 5) were transformed, via dibutyltin oxidemediated acylation, into the corresponding 2,3-di-O-benzoyl derivatives 11 and 15. Xylobiose and xylotriose were easily isolated by charcoal column chromatography from a commercially available material and converted into the di- and trisaccharide methyl 1-thio-beta-glycosides 36 and 37. The 2-and 4-nitrophenyl beta-glycosides of the beta-(1-->4)-D-xylo-oligosaccharides of dp 2-4 were synthesized by N-iodosuccinimide-silver triflate-promoted condensation using 11 and 15 as the glycosyl acceptors and ethyl 1-thio-beta-D-xylopyranoside triacetate 16, 36, and 37 as the glycosyl donors. Also described are an improved preparation of 4 and 5, and the synthesis of 1-naphthyl beta-D-xylopyranoside, as well as an alternative approach to the 2- and 4-nitrophenyl beta-xylobiosides. 相似文献
94.
95.
TH Wu TD Ting TI Okajima DR Pepperberg YK Ho H Ripps MI Naash 《Canadian Metallurgical Quarterly》1998,87(3):709-717
In budding yeast, a protein kinase called Gin4 is specifically activated during mitosis and functions in a pathway initiated by the Clb2 cyclin to control bud growth. We have used genetics and biochemistry to identify additional proteins that function with Gin4 in this pathway, and both of these approaches have identified members of the septin family. Loss of septin function produces a phenotype that is very similar to the phenotype caused by loss of Gin4 function, and the septins are required early in mitosis to activate Gin4 kinase activity. Furthermore, septin mutants display a prolonged mitotic delay at the short spindle stage, consistent with a role for the septins in the control of mitotic events. Members of the septin family bind directly to Gin4, demonstrating that the functions of Gin4 and the septins must be closely linked within the cell. These results demonstrate that the septins in budding yeast play an integral role in the mitosis-specific regulation of the Gin4 kinase and that they carry out functions early in mitosis. 相似文献
96.
Organ injury scaling: spleen and liver (1994 revision) 总被引:5,自引:0,他引:5
EE Moore TH Cogbill GJ Jurkovich SR Shackford MA Malangoni HR Champion 《Canadian Metallurgical Quarterly》1995,38(3):323-324
A case of haemangiopericytoma of the greater omentum is reported here. We discuss the presentation, treatment and prognosis of these rare tumours. 相似文献
97.
98.
WK Wang T Dudek YJ Zhao HG Brumblay M Essex TH Lee 《Canadian Metallurgical Quarterly》1998,95(10):5740-5745
The seven-transmembrane CCR5 was recently found to double as a coreceptor for a genetically diverse family of human and nonhuman primate lentiviruses. Paradoxically, the main region of the envelope protein believed to be involved in CCR5 utilization was mapped to hypervariable region 3, or V3, of the envelope glycoprotein gp120. In this study, we addressed the question of whether functional convergence in CCR5 utilization is mediated by certain V3 residues that are highly conserved among HIV type 1 (HIV-1), HIV type 2, and simian immunodeficiency virus. Site-directed mutagenesis carried out on three such V3 residues revealed that the Arg-298 of HIV-1 gp120 has an important role in CCR5 utilization. In contrast, no effect was observed for the other residues we tested. The inability of Arg-298 mutants to use CCR5 was not attributed to global alteration of gp120 conformation. Neither the expression, processing, and incorporation of mutant envelope proteins into virions, nor CD4 binding were significantly affected by the mutations. This interpretation is further supported by the finding that alanine substitutions of five residues immediately adjacent to the arginine residue had no effect on CCR5 utilization. Taken together, our data strongly suggests that the highly conserved Arg-298 residue identified in the V3 of HIV-1 has a significant role in CCR5 utilization, and may represent an unusually conserved target for future anti-viral designs. 相似文献
99.
TL Ott JG Fleming TE Spencer MM Joyce P Chen CN Green D Zhu TH Welsh PG Harms FW Bazer 《Canadian Metallurgical Quarterly》1997,57(3):621-629
Interferon tau (IFN tau) is the conceptus-produced antiluteolytic signal in ruminants. Three experiments examined the effects of s.c. administration of recombinant ovine (ro)IFN tau on interestrous interval (IEI), oxytocin (OT)-induced uterine prostaglandin F2alpha metabolite (PGFM) production, rectal temperature (RT), respiration rate (RR), and plasma concentrations of progesterone, cortisol, LH, and antiviral activity (AVA) in plasma and uterine flushings. In experiment I, 20 ewes were treated s.c. with either 0, 1, 2, or 4 mg/day roIFN tau (0.7 x 10(8) U/mg; 5 ewes/dosage) from Days 11 to 15 of the estrous cycle (estrus = Day 0) and were challenged with OT (30 IU) on Day 15. Jugular blood samples were collected at -10, 0, 10, 20, 30, 40, 50, and 60 min relative to the OT challenge and assayed for PGFM. Recombinant oIFN tau increased IEI (16.7, 18.7, and 22.6 +/- 0.6 days for 0, 2, and 4 mg roIFN tau, respectively, p < 0.01). Recombinant oIFN tau did not affect peak PGFM response to OT (2309 +/- 172 pg/ml; p > 0.1). However, the 4 mg/day dosage delayed the time to peak PGFM (32.4 vs. 47.5 +/- 3.4 min; p < 0.01, 0 vs. 4 mg) and resulted in approximately 200% higher concentrations of PGFM at 60 min post-OT (0 vs. 4 mg/day, p < 0.07). Experiment II was similar to experiment I, except that only the 0- and 4-mg/day dosages of roIFN tau were administered. Ewes were hysterectomized on Day 16, and assay of uterine flushes detected no AVA from ewes treated with either 0 or 4 mg/day roIFN tau. In experiment III, 20 ewes were treated s.c. with either 0, 2, 4, or 6 mg roIFN tau on Day 12. Blood samples, RT, and RR were obtained at frequent intervals for 24 h, and plasma was assayed for progesterone, cortisol, LH, and AVA. Plasma AVA, which increased in a dose-dependent manner, was detectable within 60 min and remained elevated at 24 h compared to control values. RT (elevated 0.5-1.0 degrees C), RR, and cortisol increased in response to all dosages of roIFN tau, with peak values occurring 150-180 min postinjection. For all dosages of roIFN tau, plasma progesterone declined from 120 to 360 min posttreatment and then returned to pretreatment values by 24 h (p < 0.01) as compared to controls. Overall, exogenous roIFN tau altered uterine PGFM response to OT from a pulse to a gradual and sustained elevation and extended IEI with only a transient decline in progesterone and mild hyperthermia, effects that are not expected to compromise pregnancy. 相似文献
100.