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111.
The FT-Raman spectra of six mammalian ivories, other than elephant and mammoth, are presented and spectral differences formulated into a protocol for the identification of animal species from the ivory samples. In this study, sperm whale, walrus, wart hog, narwhal, hippopotamus and domestic pig are considered. The results, which are obtained non-destructively from a variety of specimens, suggest that FT-Raman spectroscopy provides a potentially useful method for the identification of mammalian ivory. 相似文献
112.
Allograft or synthetic meniscal replacement has the potential to delay the arthritic sequelae of the meniscectomized knee. Meniscal implants must, however, be side and size specific. A cadaveric study was performed in which medial and lateral menisci were painted with a radiopaque tantalum powder-cyanoacrylic mixture. Radiographs of this preparation demonstrated reproducible relationships between each meniscus and established bony landmarks. When corrected for magnification, meniscal size could be derived from plain films. Meniscal width equaled the distance (coronal) from the peak of the tibial eminence to the periphery of the tibial metaphysis on anteroposterior films. Meniscal length was measured from lateral radiographs. Medial meniscal length was 80%, and lateral meniscal length was 70% of the measured sagittal length of the tibial plateau. Measurement error averaged 7.8% by these parameters. 相似文献
113.
The prevalence of hypercalcemia in patients with untreated tuberculosis (TB) varies widely between countries. Since the vitamin D status and calcium intake are important determinants of hypercalcemia in TB, these two factors were compared among four populations (U.K., Hong Kong, Malaysia, Thailand) with a low prevalence (<3%) and two populations (Sweden, Australia) with a high prevalence (>25%). In the three Asian countries, the circulating vitamin D levels are abundant, but the calcium intakes are low. Subjects from the U.K. have the lowest circulating vitamin D level of all, although their calcium intake is high. In Sweden and Australia, both the circulating vitamin D levels and calcium intakes are high. Since serum 1,25(OH)2D concentration will only be raised if its substance for extrarenal conversion, 25(OH)D, is plentiful and the effect of a given serum 1,25 (OH)2D concentration on serum calcium is determined by the calcium intake, it is postulated that the regional variation in the prevalence of hypercalcemia in TB may be due to differences in the circulating vitamin D levels and calcium intakes in these populations. 相似文献
114.
VV Kukharchuk EIu Solov'ev PP Malyshev TA Rozhkova OA Semenova EE Aronskaia 《Canadian Metallurgical Quarterly》1997,69(9):41-45
13 patients aged 39 to 60 years with coronary atherosclerosis confirmed at selective coronary angiography combined with primary hyperlipidemia (phenotypes 2a and 2b) received enduracin in a dose 1500 mg/day. As a result of the treatment total cholesterol (TC) and LDL cholesterol lowered by 10.3 and 13.1%, respectively, whereas HDL cholesterol rose by 15.2%. Half of the patients demonstrated activation of hepatic transaminases, but discontinuation of the drug was not necessary. In 3 out of 4 patients after 2 years of enduracin treatment stabilization of atherosclerosis was observed. Thus, long-term enduracin is able to inhibit progression of atherosclerosis in coronary heart disease patients. 相似文献
115.
Brain substrates of infant-mother attachment: contributions of opioids, oxytocin, and norepinephrine
The aim of this paper is to review recent work concerning the psychobiological substrates of social bonding, focusing on the literature attributed to opioids, oxytocin and norepinephrine in rats. Existing evidence and thinking about the biological foundations of attachment in young mammalian species and the neurobiology of several other affiliative behaviors including maternal behavior, sexual behavior and social memory is reviewed. We postulate the existence of social motivation circuitry which is common to all mammals and consistent across development. Oxytocin, vasopressin, endogenous opioids and catecholamines appear to participate in a wide variety of affiliative behaviors and are likely to be important components in this circuitry. It is proposed that these same neurochemical and neuroanatomical patterns will emerge as key substrates in the neurobiology of infant attachments to their caregivers. 相似文献
116.
Phylogenetic relationships of mangabeys within the Old World monkey tribe Papionini are inferred from analyses of nuclear DNA sequences from five unlinked loci. The following conclusions are strongly supported, based on congruence among trees derived for the five separate gene regions: (1) mangabeys are polyphyletic within the Papionini; (2) Cercocebus is the sister taxon to the genus Mandrillus; and (3) Lophocebus belongs to a clade with Papio and Theropithecus, with Papio as its most likely sister taxon. Morphologically based phylogenies positing mangabey monophyly were evaluated by mapping the sequences for each locus on these trees. The data seem to fit these trees poorly in both maximum-parsimony and likelihood analyses. Incongruence among nuclear gene trees occurred in the interrelationships among Lophocebus, Papio, and Theropithecus. Several factors that may account for this incongruence are discussed, including sampling error, random lineage sorting, and introgression. 相似文献
117.
Fifteen patients with posttraumatic shortened atrophic femoral nonunions were treated with one-stage lengthening. The alloimplant was composed of allogeneic antigen extracted autolyzed human bone perfused with partially purified human cortical bone morphogenetic protein associated with noncollagenous protein and used as graft. The composite was lyophilized and sterilized with ethylene oxide. All 15 nonunions were atrophic diaphyseal and were lengthened through intercalary segmental defects bridged with the human bone morphogenetic protein composite alloimplants stabilized to the medial femoral cortex through plate osteosynthesis and lag screw fixation. One lengthened proximal femur had fatigue failure of the plate and was treated successfully by exchange plating. The average increase in length was 2.8 cm (range, 1.5-5 cm) and an average percentage increase in length of 8% (range, 4%-132%) of the residual shortened femur. The human bone morphogenetic protein composite produced an immediate reactive bone formation in the host bone and progressive remodeling of the donor recipient interfaces. There were no infections, allergic reactions, clinical rejection of the human bone morphogenetic protein composite alloimplants, or evidence of malignant disease. One-stage femoral lengthening augmented with human bone morphogenetic protein composite graft bridged the intercalary defect, remodeled the atrophic host bone and restored bone continuity within 1 to 2 years. Human bone morphogenetic protein composite alloimplants are a substitute of autogeneic bone graft and offer an alternative to iliac crest bone without the associated morbidity. 相似文献
118.
119.
Cyclohexane transformation was studied during water chlorination. Three mechanisms of cyclohexane transformation in the presence of chlorine were determined. Over 70 reaction products were identified. Five of them have mutagenic activity. 相似文献
120.
EE Mason 《Canadian Metallurgical Quarterly》1998,8(5):524-529
The ribulose bisphosphate carboxylase/oxygenase rbcL and rbcS genes of a carbon monoxide-oxidizing bacterium, Hydrogenophaga pseudoflava DSM 1084, were cloned and sequenced. The cloned rbcL and rbcS genes had open reading frames of 1422 and 351 nucleotides encoding RbcL and RbcS with calculated molecular masses of 52,689 and 13,541, respectively. The known active site residues in other RbcL proteins were conserved in the H. pseudoflava proteins. The H. pseudoflava RbcS protein lacked the 12-residue internal sequence found in the plant enzymes. The 2 genes were separated by a 134 bp intergenic region and cotranscribed as a 2.0 kb rbcLS mRNA. Novel two perfect 9 bp direct repeats overlapping with two dyad symmetries were found in the rbcLS promoter region. 相似文献