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41.
Covariance structures analysis is often used in nursing research to appraise statistical models reflecting complex human health processes. The model selection approach in covariance structures analysis is designed to select the "best" model from a specified set of theoretically defensible, competing alternatives, all of which are viewed as approximations. Model selection criteria explicitly incorporate both model misfit in the population and sampling error to evaluate the set of models. The result is that interpretability of model parameters and goodness-of-fit are enhanced simultaneously. Relative merits of the model selection approach are identified in light of technical concerns, parsimony, and use of scientific theory in nursing. 相似文献
42.
KJ Zucker SJ Bradley G Oliver J Blake S Fleming J Hood 《Canadian Metallurgical Quarterly》1996,30(4):300-318
Women with congenital adrenal hyperplasia (CAH) (N = 31) and their unaffected sisters or female cousins (N = 15) participated in a study of psychosexual development. All participants were > or = 18 years of age (mean age, 25 years; range, 18-40). Comparisons were also made between the CAH women with the salt-wasting (SW) form of the disorder and those with simple virilization (SV). A psychosexual assessment protocol examined six variables: (1) sex assignment at birth (probands only); (2) recalled sex-typed behavior during childhood; (3) gender identity and gender role identification in adulthood; (4) relationship status; (5) sexual orientation in fantasy; and (6) sexual orientation in behavior. Salt-wasting status and sex assignment at birth were also ascertained for the CAH women who either refused to participate in the study (N = 10) or could not be traced (N = 13). Compared to the controls, the women with CAH recalled more cross-gender role behavior and less comfort with their sense of "femininity" during childhood. The two groups did not differ in degree of gender dysphoria in adulthood, although the probands showed more cross-gender role identification. Three of the nonparticipant probands were living, as adults, in the male social role (2 reared from birth as boys and 1 who changed from the female to the male social role during adolescence). The CAH women and the controls did not differ in relationship status (married/cohabiting vs. single). The CAH women had lower rates of exclusive heterosexual fantasy and fewer sexual experiences with men than the controls; however, the CAH women did not have more sexual experiences with women than the controls. Comparisons between the SW and SV revealed several differences: the SW were less likely to be assigned to the female sex at birth, recalled more cross-gender role behavior during childhood, were less likely to be married or cohabiting, and had lower rates of sexual experiences with men. The results were discussed in relation to the effects of prenatal androgens on psychosexual differentiation. 相似文献
43.
Using PCR with degenerate primers and screening of a human B-cell lymphoblast cDNA library, a full-length cDNA encoding a 375-amino-acid protein was isolated. It contains seven regions of hydrophobic amino acids probably representing membrane-spanning domains of a novel heptahelix receptor, tentatively named CMKRL2. It shows nearly 30% overall identity with the high-affinity IL8 receptor and similar degree of homology with other chemoattractant receptors, including the "fusin" coreceptors for HIV1. Measurements of various transduction pathways following application of a panel of chemokines to transfected cells failed to evoke any reproducible response. Although the natural ligand for CMKRL2 could, thus, not be identified, receptor expression in spleen and lymph nodes as well as in Burkitt's lymphoma (irrespective of EBV status) supports a functional role in activated B-cells. Receptor message was ubiquitously distributed in normal peripheral tissues and CNS, suggesting that CMKRL2 is expressed in widespread cell populations, such as macrophages and neuroglia. 相似文献
44.
H Kopsa J Zazgornik P Schmidt H Pall SJ Pok PM Bayer P Balcke P Pils 《Canadian Metallurgical Quarterly》1977,107(27):942-947
Two cases with acute renal failure after prolonged hypothermia are presented. Both patients were found in come, became rapidly uremic and required hemodilaysis treatment. Although the laboratory findings were typical of severe muscle damage, e.g. elevated levels of serum creatinine phosphokinase, serum lactic dehydrogenase and serum aldolase activities, visible "crush-injuries" were not found. Acute renal failure was characterized by extreme catabolism and severe metabolic acidosis. After 4 and 10 hemodialyses respectively, the patients became polyuric and finally were discharges with normal renal and muscle function. Hypotension with diminished renal perfusion and nontraumatic rhabdomyolysis due to prolonged hypothermia are regarded as the dominant pathogenetic factors in the acute renal failure. 相似文献
45.
The roles chronological age and gender play in subjective time experience were explored in a sample of 294 adult men and women. Subjective time experience (STE: the difference between subjective age and chronological age) was found to vary widely among individuals, with some being "accurate" (SA = CA), and others either "retarded" (SA less than CA) or "advanced" (SA greater than CA). Males were more retarded in STE than females at every point in the lifespan, and patterns of age differences in adulthood differed for the two sexes as well. The results suggest that chronological age may play a key role in transitions in STE, and that chronological age is more significant in the STE of women than in the STE of men. 相似文献
46.
47.
Shima Yousefi Zahra Emam-Djomeh Sayed Mohammad Ali Mousavi Gholam Reza Askari 《Food and Bioprocess Technology》2012,5(4):1328-1339
Pomegranate juice was concentrated by conventional heating and microwave heating at different operational pressures (12, 38.5,
and 100 kPa), and their effects on evaporation rate and quality attributes of concentrated juice were investigated. The final
juice concentration of 40° Brix was achieved in 140, 127, and 109 min at 100, 38.5, and 12 kPa, respectively, by using conventional
heating. Applying microwave energy decreased required times to 118, 95, and 75 min. The changes in color, anthocyanin content,
and antioxidant capacity during concentration processes were investigated. L*, a*, and b* parameters were measured to estimate the intensity of color loss. All Hunter color parameters decreased with time. Results
showed that the degradation of color, anthocyanins, and antioxidant activity were more important in conventional heating compared
to microwave heating method. Degradation rates increases by increasing process pressure. A first-order kinetics model was
applied to modeling changes in total solid content, anthocyanin content, and antioxidant capacity. 相似文献
48.
49.
C Robinson SJ Brookes J Kirkham WA Bonass RC Shore 《Canadian Metallurgical Quarterly》1996,10(2):173-9; discussion 179-80
Amelogenin-mineral interactions were investigated using an in vitro binding approach. Rat incisor enamel matrix proteins (mainly amelogenins) were dissolved in synthetic enamel fluid and allowed to equilibrate with deproteinised developing enamel crystals. The results showed that amlogenin proteins of 21, 23, 24, 26 and 27-kDa (corresponding to nascent and partially degraded amelogenins) were associated with the crystals whilst the lower Mr amelogenins (< 21 KDa) remained free in the synthetic enamel fluid. These data suggest the nascent and partially degraded amelogenins may interact with developing enamel crystals and could influence their growth. Albumin-mineral interactions were investigated by extracting developing rat incisor enamel with synthetic enamel fluid. Insoluble material (including the enamel crystals) was then further extracted with 0.1 M phosphate buffer (pH 7.4) to desorb any mineral bound proteins. Western blotting using anti-albumin antibodies showed that almost all of the albumin from the secretory stage enamel and a significant proportion of the albumin present in early transition stage was extractable in the synthetic enamel fluid. However, synthetic enamel fluid did not extract albumin from late transition or maturation stage tissue, which could only be removed following further extraction with phosphate buffer. Albumin degradation was apparent during the transition and maturation stages, where it is degraded and ultimately removed. This binding pattern may be related to amelogenin degradation and removal during the transition stage, permitting albumin access to the previously obscured crystal surfaces. That the secretory stage matrix appears to "protect" secretory stage crystals from albumin may be an important consideration in the aetiology of enamel hypoplasias (i.e. incomplete crystal growth) and when using dissociative extraction procedures for the identification of mineral bound proteins. 相似文献
50.
We have analyzed the T-cell receptor (TCR) V beta repertoire using polymerase chain reaction (PCR) in a cohort of eight patients receiving allogeneic bone marrow transplantation (BMT) from related and unrelated donors at the City of Hope. Results of PCR studies from graft-versus-host disease (GVHD) skin lesions show a bias in the usage of TCR V beta families, whereas examination of peripheral blood (PB) withdrawn at the same time did not reveal a similar phenomenon. In one such family, TCR V beta 2 is predominantly expressed in 7 of 7 biopsy specimens examined. V beta 2 TCR expression from these patients was analyzed more extensively using a combination of individual TCR gene cloning, followed by sequence analysis. We found evidence of oligoclonal expansion of single V beta 2-bearing TCRs in GVHD lesions, and in the PB of some patients after diagnosis of GVHD. In contrast, GVHD-negative biopsy samples showed no evidence for clonotypic TCR amplification. Sequence-specific TCR CDR3 region probes were derived from analysis of the predominant expressed TCR in GVHD lesions, and used to probe Southern blots of amplified V beta 2 TCR mRNA from PB and tissue from BMT recipients and their respective donors. In most cases the probes are highly specific in detecting TCR expression from GVHD lesions alone, although in several instances expression could be detected in PB after GVHD diagnosis. These data provide supporting evidence for the hypothesis that acute GVHD is associated with expansion of T-cell clones expressing antigen-specific TCRs that may contribute to the disease pathology. 相似文献