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41.
P Sidhu SW MacGowan 《Canadian Metallurgical Quarterly》2003,24(4):668; author reply 668-668; author reply 669
42.
RE Hughes AG Schneeberger KN An BF Morrey SW O''Driscoll 《Canadian Metallurgical Quarterly》1997,6(5):444-448
A retrospective case reference study examining the use of alcohol and tobacco in 303 women aged 40 or over suffering from oral or oropharyngeal cancer was conducted in the south-west Netherlands. Both alcohol and tobacco consumption are important in the development of oral and oropharyngeal cancer with increased consumption of both markedly increasing the risks of cancer, but alcohol having the greater effect. 相似文献
43.
The human follicle-stimulating hormone receptor (FSH-R) consists of two distinct domains of >330 amino acids, the N-terminal extracellular exodomain and membrane-associated endodomain. The exodomain alone binds hormone with high affinity, whereas the endodomain is the site of receptor activation. Coordination of these two domains is essential for successful hormone action but little is known about their functional and structural relationship. In this communication, we report that exoloop 3 of FSH-R constrains follicle-stimulating hormone binding to the exodomain. When the FSH-R exodomain was prepared by truncating its endodomain, the hormone binding affinity of the exodomain was slightly improved, compared with the wild type receptor. The binding affinity was further improved by >3-fold when the exodomain was attached to the membrane-associated domain of CD8. These results suggest that the FSH-R endodomain attenuates hormone binding at the exodomain. As a first step to test this hypothesis, the 11 amino acids except Ala589 of exoloop 3 were individually substituted with Ala. Ala substitution for Leu583 or Ile584 improved the hormone binding affinity by 4-6-fold while totally abolishing cAMP induction, indicating an inverse relationship. The Ala substitution for Lys580 or Pro582 had a similar trend but to a lesser extent. This significant improvement in the binding affinity suggests that the four residues at the N-terminal region of exoloop 3 interact with the exodomain and constrain the hormone binding in the wild type receptor. This effect is specific since substitutions for other than the 4 residues did not improve the hormone binding affinity. Computer modeling shows that the 4 residues can be positioned on one side of exoloop 3. This result and the apparent inverse relationship of hormone binding and cAMP induction suggest that these two essential functions may work against each other. Therefore, hormone binding might be compromised to preserve cAMP inducibility while maintaining a reasonably high, but below maximum, binding affinity. 相似文献
44.
Provision of automated support for planning protocol-directed therapy requires a computer program to take as input clinical data stored in an electronic patient-record system and to generate as output recommendations for therapeutic interventions and laboratory testing that are defined by applicable protocols. This paper presents a synthesis of research carried out at Stanford University to model the therapy-planning task and to demonstrate a component-based architecture for building protocol-based decision-support systems. We have constructed general-purpose software components that (1) interpret abstract protocol specifications to construct appropriate patient-specific treatment plans; (2) infer from time-stamped patient data higher-level, interval-based, abstract concepts; (3) perform time-oriented queries on a time-oriented patient database; and (4) allow acquisition and maintenance of protocol knowledge in a manner that facilitates efficient processing both by humans and by computers. We have implemented these components in a computer system known as EON. Each of the components has been developed, evaluated, and reported independently. We have evaluated the integration of the components as a composite architecture by implementing T-HELPER, a computer-based patient-record system that uses EON to offer advice regarding the management of patients who are following clinical trial protocols for AIDS or HIV infection. A test of the reuse of the software components in a different clinical domain demonstrated rapid development of a prototype application to support protocol-based care of patients who have breast cancer. 相似文献
45.
Many proteins require enzymatic assistance in order to achieve a functional conformation. One rate-limiting step in protein folding is the cis-trans isomerization of prolyl residues, a reaction catalyzed by prolyl isomerases. SurA, a periplasmic protein of Escherichia coli, has sequence similarity with the prolyl isomerase parvulin. We tested whether SurA was involved in folding periplasmic and outer membrane proteins by using trypsin sensitivity as an assay for protein conformation. We determined that the efficient folding of three outer membrane proteins (OmpA, OmpF, and LamB) requires SurA in vivo, while the folding of four periplasmic proteins was independent of SurA. We conclude that SurA assists in the folding of certain secreted proteins. 相似文献
46.
Bipolar illness may be characterized by dysregulation and dysfunction of biologically active ions and ion pumps, respectively. In an effort to examine whether purported physiologic abnormalities may have functional counterparts, nerve conduction velocities (NCVs) and H-reflex recovery were examined in 7 acutely manic, 11 euthymic bipolar, 13 remitted schizophrenic, and 6 normal control individuals. All electrophysiologic tests were clinically normal. However, euthymic bipolar patients had significantly slower NCVs than either manic or normal individuals. Percent decrement of H-reflex recovery was nonsignificantly increased in manic versus euthymic bipolar subjects. Data analysis suggests lithium was not responsible for these changes. These data indicate that different mood states in bipolar illness are associated with alterations in electroneurophysiologic function. 相似文献
47.
We characterized the lymphocyte subpopulations and investigated the effect of age on cellular and humoral immunity, development of lymphoid organs, and the relative proportions of CD4+ and CD8+ cells in turkeys. The mitogenic responses of peripheral T cells were poorly developed at hatch but developed rapidly after hatch and reached adult levels by 2 weeks-of-age. The average percentage of CD4+ cells was 45, 29.8, and 26.3 in the thymi, peripheral blood, and spleens, respectively, in turkeys. The mean percentage of CD8+ cells in the thymi, peripheral blood, and spleens of turkeys was 53.8, 13.6, and 15.5, respectively. Age did not influence the relative proportions of CD4+ and CD8+ T cells in the spleens and peripheral blood of turkeys. The mean percentages of IgM+ cells in the bursae and spleens were 78.5 and 26.8, respectively. Day-old turkeys did not develop detectable antibodies to either thymus dependent or independent antigens. However, 2 week or older turkeys showed good humoral responses. Inoculation of BSA at hatch induced tolerance, whereas injection of SRBC did not. Analysis of relative organ weights of turkey lymphoid organs showed that spleens and thymi developed rapidly during the first week-of-age. 相似文献
48.
Motion based object tracking with mobile camera 总被引:4,自引:0,他引:4
Kyu Won Lee Seong Won Ryu Soo Jong Lee Kyu Tae Park 《Electronics letters》1998,34(3):256-258
An efficient algorithm which detects and tracks a moving object is proposed. The global motion energy caused by camera movement is eliminated by finding the maximal matching position with the cross-correlation value between two consecutive frames using the spiral scanning technique. The region of a moving object is segmented exactly by combining the results of the temporal derivatives and edge map from one image, and the actual centroid of the moving object is determined as the mid-point of the cumulative distribution of the projection profile of the region 相似文献
49.
Large scale use of lysozyme for periplasmic release has been impeded by the cost of the pure enzyme and its subsequent presence as a contaminant in later downstream processing steps. In this paper, we discuss the use of lysozyme for pilot scale recovery of a periplasmic enzyme from E. coli. The effects of concentration of sucrose, lysozyme and cells on periplasmic enzyme release were examined. Lysozyme concentration can be reduced 5-fold from previous reports and a reduction in sucrose concentration from 20 to 15% (w/v) allows an improvement in centrifugal harvesting by reducing viscosity. High levels of release were still achieved using this technique and further improvements in yield were obtained by optimising other components of the releasing mixture. Results show that some release is still achieved in circumstances where no lysozyme use is possible. Results also indicate that a substantial proportion (up to 70%) of lysozyme remains bound to the cellular debris after its action and is removed with this material. 相似文献
50.
Twenty mothers of preterm babies who had survived to 1 year old, were matched for age and parity of the mother and time of birth of the baby, with 20 mothers delivering fullterm. Bone mineral, body composition and anthropometric measurements were obtained for each mother and analysed using paired t-tests. The only significant difference (P < 0.01) between the groups was a lower fat-free mass in the preterm mothers calculated from skinfold thickness measurements. 相似文献