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91.
92.
M Paulli E Berti E Boveri S Kindl E Bonoldi C Gambini R Rosso G Borroni V Straccapansa U Magrini JE DeCoteau PH Krammer P M?ller ME Kadin 《Canadian Metallurgical Quarterly》1998,29(11):1223-1230
The spectrum of CD30+ cutaneous lymphoproliferative disorders is characterized by the histology of a high-grade lymphoma but frequent clinical regression of skin lesions in lymphomatoid papulosis (LyP) and occasional regression in CD30+ large cell lymphomas (LCLs). A recent study shows that apoptosis may be a significant mechanism of regression of LyP (Arch Dermatol 133:828-833, 1997). Therefore, we studied expression of proteins that induce apoptosis, including CD27, CD40, CD95, and nerve growth factor receptor (NGF-R), as well as anti-apoptotic protein bcl-2 in skin lesions from 25 patients within the spectrum of CD30+ cutaneous lymphoma. Our results show consistent expression of CD95 (APO-1/Fas), but rare or absent expression of CD27, CD40, and NGF-R on tumor cells from both regressing LyP lesions and nonregressing CD30+ lymphomas. Bcl-2 was expressed at low levels in LyP and at high levels in pleomorphic CD30+ lymphomas. These results indicate that, in addition to CD30, CD95 expression is preferentially expressed at high levels in all cutaneous CD30+ lymphomas and suggest that CD95 may play a role in the regression of CD30+ skin lesions. Expression of bcl-2 appears to protect tumor cells from apoptosis in CD30+ lymphoproliferative disorders. 相似文献
93.
PH Katelaris TV Nguyen GJ Robertson R Bradbury MC Ngu 《Canadian Metallurgical Quarterly》1998,28(5):633-638
1. Heterozygous naked neck birds were raised under natural spring (average 21.2 degrees C) and summer temperatures (average 27.1 degrees C) to investigate the influence of dietary energy on broiler performance, carcase yield and nutrient composition of breast meat. 2. Birds were fed on a low energy diet of 12.12 MJ ME/kg, a medium energy diet of 12.96 MJ ME/kg and a high energy diet of 13.79 MJ ME/kg with 2 protein concentrations per energy treatment, 230 and 200 g/kg, from 0 to 3 and 3 to 7 weeks of age, respectively. 3. Summer rearing resulted in a decrease in body weight, body weight gain, carcase weight and carcase part yields of birds. 4. Increasing dietary energy from 12.12 to 13.79 MJ ME/kg increased body weight at 3 and 7 weeks, body weight gains from 0 to 3 and 3 to 7 weeks, carcase weights and relative abdominal fat weights of birds in a linear manner. There was no effect of dietary energy on the nutrient composition of breast meat. 5. It was concluded that there was no differences in dietary energy requirements of heterozygous naked neck birds when grown under natural optimum (21.2 degrees C) and summer temperatures (27.1 degrees C). 相似文献
94.
HOAgraveNG XUÂN PHÚ 《International journal of control》2013,86(5):1867-1882
We solve a linear optimal control problem with state and control restrictions by the method of region analysis, where the state equations describe the flow in a directed graph without a circuit. The results are used for the optimal control of a system of hydroelectric power plants. 相似文献
95.
Gravitropism allows plant organs to direct their growth at a specific angle from the gravity vector, promoting upward growth for shoots and downward growth for roots. Little is known about the mechanisms underlying gravitropic signal transduction. We found that mutations in the ARG1 locus of Arabidopsis thaliana alter root and hypocotyl gravitropism without affecting phototropism, root growth responses to phytohormones or inhibitors of auxin transport, or starch accumulation. The positional cloning of ARG1 revealed a DnaJ-like protein containing a coiled-coil region homologous to coiled coils found in cytoskeleton-interacting proteins. These data suggest that ARG1 participates in a gravity-signaling process involving the cytoskeleton. A combination of Northern blot studies and analysis of ARG1-GUS fusion-reporter expression in transgenic plants demonstrated that ARG1 is expressed in all organs. Ubiquitous ARG1 expression in Arabidopsis and the identification of an ortholog in Caenorhabditis elegans suggest that ARG1 is involved in other essential processes. 相似文献
96.
The beta-lactamase genes of Klebsiella oxytoca were previously divided into two main groups: bla(OXY-1) and bla(OXY-2). The two beta-lactamase groups were each represented by beta-lactamases with four different pIs. In each group, one form of beta-lactamase is more frequent than the others combined. The beta-lactamase gene of each representative beta-lactamase with a different pI that was not yet sequenced (pIs 5.7, 6.8 [OXY-2], 7.1, 8.2, and 8.8 [OXY-1]) was cloned and sequenced. The susceptibility patterns as well as relative rates and kinetic parameters for beta-lactam hydrolysis revealed that OXY-2 enzymes hydrolyzed several of the beta-lactams that were examined (carbenicillin, cephalothin, cefamandole, ceftriaxone, and aztreonam) at a greater rate than the OXY-1 enzymes did. Comparison of K. oxytoca beta-lactamases with plasmid-mediated extended-spectrum beta-lactamases MEN-1 and TOHO-1 implied that the threonine at position 168 present in OXY-2 beta-lactamase instead of the alanine in OXY-1 could be responsible for its modified substrate hydrolysis. In each group, the beta-lactamase with a variant pI differs from the main form of beta-lactamase by one to five amino acid substitutions. The substrate profile and the 50% inhibitory concentrations revealed that all substitutions differing from the main form of beta-lactamase were neutral except one difference in the OXY-1 group. This substitution of an Ala to a Gly at position 237 increases the hydrolysis of some beta-lactams, particularly aztreonam; decreases the hydrolysis of benzylpenicillin, cephaloridine, and cefamandole, and decreases the susceptibility to clavulanic acid (fivefold increase in the 50% inhibitory concentration). 相似文献
97.
Significant cleavage by hammerhead ribozymes requires activation by divalent metal ions. Several models have been proposed to account for the influence of metal ions on hammerhead activity. A number of recent papers have presented data that have been interpreted as supporting a one-metal-hydroxide-ion mechanism. In addition, a solvent deuterium isotope effect has been taken as evidence against a proton transfer in the rate-limiting step of the cleavage reaction. We propose that these data are more easily explained by a two-metal-ion mechanism that does not involve a metal hydroxide, but does involve a proton transfer in the rate-limiting step. 相似文献
98.
A Renstr?m S Gordon PH Larsson RD Tee AJ Newman Taylor P Malmberg 《Canadian Metallurgical Quarterly》1997,27(11):1314-1321
BACKGROUND: Mouse and rat urinary proteins are potent occupational allergens for exposed personnel. Methods of measuring airborne allergens differ greatly, and reported levels of allergens vary considerably between laboratories. OBJECTIVES: To compare the values obtained using two different methods of allergen detection. METHODS: Air samples were collected in rat rooms in Sweden and the United Kingdom at 2 L/min on to polytetrafluoroethylene (PTFE) filters and extracted in buffer containing 0.5% v/v Tween 20. Airborne rat urinary allergen (RUA) was measured in all samples by both RAST inhibition using a polyclonal human serum pool (UK) and a two monoclonal antibody sandwich ELISA employing antibodies specific for Rat n 1.02 (alpha2u-globulin) (Sweden). RESULTS: The two methods gave values which were correlated (r2 log values = 0.72, P<0.0001), but differed by several orders of magnitude (median [range] ratio of RAST inhibition/ELISA = 316 [7-26(80)]. There was a systematic bias: as the absolute values increased, the difference in the measurements increased. The rat urine standards used were antigenically similar. CONCLUSIONS: A large contrast in RUA values obtained from the two assays was observed in this study. This may be primarily due to methodological differences, but variations in antibody specificities or composition of allergenic epitopes in the air samples may contribute. The results demonstrate that standardization of methods and antibodies is necessary before interlaboratory comparisons can be made. 相似文献
99.
H Kappauf WM Gallmeier PH Wünsch HO Mittelmeier J Birkmann G Büschel G Kaiser J Kraus 《Canadian Metallurgical Quarterly》1997,8(10):1031-1039
Spontaneous remission of cancer (SR) is defined as a complete or partial, temporary or permanent disappearance of all or at least some relevant parameters of a soundly diagnosed malignant disease without any medical treatment or with treatment that is considered inadequate to produce the resulting regression. We report the case of a 61-year-old man who presented with extensive metatastic disease five months after pneumonectomy for poorly differentiated large cell and polymorphic lung cancer. A vast metastatic tumour mass of the abdominal wall was confirmed histolologically and there was clinical and radiographic evidence of liver and lung metastases. Eight months later, the patient was operated on for a hernia, which had developed in the inguinal biopsy scar and the surgeon confirmed complete clinical SR of the abdominal wall metastases. Again five months later there was no longer any radiologic evidence of liver and lung metastases. Complete remission has persisted more than five years. Histology of the primary and of the abdominal metastases were reviewed by several independent pathologists. SR is an extremly rare event in lung cancer. This is the first documented case of clinically evident visceral metastases of a bronchiogenic adenocarcinoma developing after complete resection of the primary and then showing complete SR. The epidemiology of SR is reviewed and possible mechanisms involved in SR are discussed. 相似文献
100.
RA Fratti PH Belanger MA Ghannoum JE Edwards SG Filler 《Canadian Metallurgical Quarterly》1998,66(1):191-196
MRL-lpr/lpr mice spontaneously develop manifestations of autoimmunity including arthritis, vasculitis, and glomerulonephritis. The paramagnetic molecule nitric oxide has been implicated as an effector molecule in initiation and propagation of these inflammatory conditions. In this study, we utilized electron paramagnetic resonance spectroscopy to directly detect nitrosylated protein complexes as products of nitric oxide in whole blood and in kidneys of MRL-lpr/lpr mice. Electron paramagnetic resonance spectra of blood samples from MRL-lpr/lpr mice showed nitrosyl hemoglobin species. Amounts of blood nitrosyl hemoglobin in MRL-lpr/lpr mice were significantly increased as compared to age-matched control mice. Electron paramagnetic resonance spectra of MRL-lpr/lpr kidney tissue exhibited a signal characteristic of a dinitrosyl-iron-dithiolate complex at g approximately 2.04. Formation of nitrosylated nonheme protein in diseased kidneys is associated with development of glomerulonephritis in the autoimmune mice. The presence of nitrosylated nonheme protein indicates the formation of nitric oxide within the kidneys of the diseased mice signifying in situ renal nitric oxide formation. 相似文献