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111.
D. T. Sprague T. M. Haard J. B. Kycia M. R. Rand Y. Lee P. J. Hamot W. P. Halperin 《Journal of Low Temperature Physics》1995,101(1-2):185-194
We report pulsed nuclear magnetic resonance (NMR) measurements of the transverse frequency and magnetization of3 He confined in aerogel with 98.2% open volume porosity. A homogeneous superfluid phase is observed at pressures, P > 12 bar, accompanied by a sharp onset of frequency shifts showing little or no textural broadening; a result quite unexpected for3He confined in random porous media. The transition temperatures and order parameter are both significantly suppressed from their bulk values and the magnetization data indicate this low temperature phase is an equal-spin pairing superfluid. For NMR tipping angles greater than 40 ° the resonance frequency drops abruptly to the normal state value. This tip angle dependence is not consistent with either the bulk3He-A or3He-B superfluid phases. 相似文献
112.
High dose chemotherapy and stem-cell rescue (bone marrow transplantation) is used increasingly in the treatment of malignant disorder. Numerous trials have demonstrated the effectiveness of bone marrow transplantation in the treatment of non-Hodgkin's lymphoma. However, there are many unanswered questions as to the role of high-dose therapy in certain subtypes of lymphoma, the timing of transplant, and even the type of transplant to perform. An attempt will be made to clarify many of these unanswered questions. The utilization of high-dose therapy for non-Hodgkin's lymphoma is recommended for most patients who have relapsed after initial therapy. Transplantation in first remission is not recommended routinely. Allogeneic bone marrow transplantation should by reserved for individuals with poorly responding disease or in individuals with bone marrow involvement. The precise roles of purging and transplantation of individuals with low grade lymphoma are being investigated. 相似文献
113.
We show here that treatment of 3T3-L1 cells with leukemia inhibitory factor (LIF) stimulated Raf-1 activity in a time- and dose-dependent manner. Although phorbol ester failed to activate Raf-1 directly, a protein kinase C-stimulated signal was found to be necessary, but not sufficient, for LIF-mediated activation of Raf-1. Elevation of intracellular cAMP levels completely blocked Raf-1 activation by LIF, but was without effect on the magnitude of mitogen-activated protein kinase (MAPK) stimulation by the cytokine, suggesting the presence of a Raf-1-independent, cAMP-insensitive MAPK kinase kinase (MAPKKK) pathway in 3T3-L1 cells. Mono Q-fractionation of LIF-stimulated 3T3-L1 extracts identified a single peak of MAPKKK activity that was largely insensitive to elevated intracellular levels of cAMP, and that failed to correlate with stimulation of either Raf-1 or MEKK1 protein kinases. Our results demonstrate that LIF-mediated activation of the MAP kinase cascade in 3T3-L1 cells proceeds through both Raf-1-dependent and -independent pathways which differ in their sensitivity to inhibition by intracellular cAMP. 相似文献
114.
We sought to determine whether intracellular or extracellular events contribute to the decrease in circulating antithrombin (AT) levels that is seen in subjects with the Utah mutation (Pro 407 to Leu). Site-directed mutagenesis was used to recreate this mutation within a previously characterized rabbit AT cDNA. Cell-free expression of the mutated cDNA yielded an AT protein that failed to react with thrombin. Expression of the rabbit AT-Utah protein in transiently transfected Cos cells resulted in a 10-fold decrease in the amount of AT antigen detected in the conditioned media, as compared with that seen with the wild-type recombinant AT. This effect was not caused by variations in transfection efficiency, because AT levels were normalized to the product of a cotransfected plasmid, chloramphenicol acetyl transferase. Moreover, on Northern blot analysis, AT mRNA levels were comparable in cells expressing either the rabbit AT-Utah or wild-type recombinant rabbit AT. Immunoblots of conditioned media from the two populations of transfected cells showed that the recombinant AT-Utah protein was intact. The results obtained with Cos cells were reproduced using permanently transfected Chinese hamster ovary (CHO) cells. Pulse-chase experiments with the CHO lines showed that both initial levels of rabbit AT-Utah after the pulse labeling and the rate of subsequent secretion during the chase period were reduced compared with that seen with cells expressing the wild-type AT. The observed reduction in AT secretion was also observed for the AT-Oslo mutation (Ala 404 to Thr) when recreated in the rabbit AT background, and expressed in Cos cells. In these experiments, the media levels of mutant AT were reduced by 50%, compared with wild-type. These results show that intracellular events, as opposed to accelerated clearance or other extracellular causes, contribute to the paucity of AT secretion seen in these strand 1C AT mutants. 相似文献
115.
AW Bradbury DJ Adam KR Makhdoomi WP Stuart JA Murie AM Jenkins CV Ruckley 《Canadian Metallurgical Quarterly》1998,85(5):645-647
BACKGROUND: This study reviews the results of infrarenal abdominal aortic aneurysm (AAA) surgery over 21 years (1 January 1976 to 31 December 1996). METHODS: A prospectively gathered database was analysed. RESULTS: Infrarenal AAA repair was performed in 1515 patients: 492 (32.5 per cent) had elective repair of an asymptomatic AAA; 194 (12.8 per cent) had elective repair of a symptomatic AAA; 156 (10.3 per cent) had emergency repair of a symptomatic non-ruptured AAA; and 673 (44.4 per cent) had surgery for a ruptured AAA. The 30-day and/or same admission mortality rates were 6.1, 5.8, 14.1 and 37 per cent respectively. Operative mortality increased in all four groups over the study interval, although this only attained statistical significance in patients having elective repair of a symptomatic, non-ruptured AAA. There was a significant increase in the age of patients undergoing elective repair of an asymptomatic AAA, but not in the other three groups. There was also a significant increase in the proportion of straight 'tube' grafts inserted in all four groups. CONCLUSIONS: It remains the minority of patients who have elective operation before the onset of symptoms and/or rupture. Despite anaesthetic and surgical specialization, the results of AAA repair have not improved over the past two decades. Operative mortality may be increasing, possibly because of the increasing age and associated comorbidity of the patients presenting to this unit. 相似文献
116.
Vibrio cholerae O1 strains isolated mostly in Japan between 1977 and 1995 were typed according to restriction fragment patterns by cleavage of genomic DNA with Sfi I and Not I and separation by Pulsed-field gel electrophoresis (PFGE). Two hundred sixty five strains from human were divided into 60 PFGE patterns (provisional types). Strains of type 2-3, 3-4, 4-5 and 51-54 were dominant in the Philippines, Thailand, India and Indonesia, respectively. Types 1-1, 2-3, 2-53, and 3-4 were detected over a long period of time in contrast to the other types. Strains of the same type (Types 1-1, 2-3, 2-53 and others) isolated from the Japanese who had never been outside Japan were often found among strains from Southeast Asia. Most strains from humans were cholera-toxin (CT)-positive, while those from the environment and the sea were generally not. 23 strains from the environment and the sea in Japan were divided into 12 types. Strains of the same types as CT-positive strains from humans could not be found in the environment and sea. These results suggest that cholera in Japan is closely related with cholera in Southeast Asia and PFGE is useful for epidemiological analysis of cholera in Japan. 相似文献
117.
WP Sullivan 《Canadian Metallurgical Quarterly》1998,(80):25-33
Because many consumers view spirituality as important in their recovery, mental health professionals can benefit from a clearer understanding of the role of religion from the consumer's perspective. 相似文献
118.
119.
WP Witjes MJ de Wildt PF Rosier CT Caris FM Debruyne JJ de la Rosette 《Canadian Metallurgical Quarterly》1996,156(3):1026-1034
PURPOSE: We quantified the physiological variability of clinical and pressure-flow study variables in patients with symptomatic benign prostatic enlargement. MATERIALS AND METHODS: Symptom scores were measured, and advanced urodynamic studies with pressure-flow analysis were performed in 178 patients before and 6 months after a period a watchful waiting. RESULTS: Patients without bladder outlet obstruction experienced significant symptomatic improvement. Symptoms in patients with obvious bladder outlet obstruction did not improve significantly. The reproducibility of mean pressure-flow variables was evident. However, there was an important intra-individual variability. Patients with obvious bladder outlet obstruction showed a significant decreases in detrusor pressure at maximal flow of 14cm. water, a significant decrease in the urethral resistance factor of 7 cm. water and a significant decrease of 1 obstruction class on the linear passive urethral resistance relation nomogram, indicating less severe bladder outlet obstruction. CONCLUSIONS: Mean differences among therapy groups must be regarded critically, especially when the difference are slight and possibly within physiological variability. 相似文献
120.