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991.
Haptoglobin (Hp) groups were determined in 65 patients with dementia of Alzheimer type (DAT) and 74 with multi-infarct dementia (MID). The increased Hp1 gene frequency among patients with DAT described by other investigators could not be confirmed in this study. The patients showed no significant difference from the controls with respect to phenotype and gene frequencies, and there were no significant differences between early and late onset cases of DAT.  相似文献   
992.
Haptoglobin groups and rheumatoid arthritis   总被引:2,自引:0,他引:2  
Haptoglobin types were determined in 200 patients with rheumatoid arthritis (RA) subdivided according to sex and familial occurrence of polyarthritis. A highly significant excess of the Hp2 gene was found among patients with a family history of polyarthritis, more pronounced among males. The possible association between Hp2 and predisposition for increased immune reactivity is discussed.  相似文献   
993.
Sutural morphogenesis in the mouse calvaria: the role of apoptosis   总被引:5,自引:0,他引:5  
Sutural morphogenesis was studied in calvariae of fetal and newborn 16- to 26-day postconception C57B1/6J mice. The squamoid pattern characteristic of most calvarial sutures appeared to be established during the phase of approach of the adjacent bone territories as they assumed different ecto/ifendocranial planes within the desmocranium. When this stratification failed, apoptosis, a form of cell death, was seen to occur upon physical contact of the leading osteogenic cells of each heterotopic bone territory. Apoptosis appeared as part of a secondary morphogenetic mechanism preventing physical contact and resultant fusion of adjacent mineralized zones, as well as enhancing appearance of the usual pattern of overlap of calvarial sutures.  相似文献   
994.
The chemical composition of chromatin from the livers of 12-, 15- and 19-day-old embryos, of 1-day-old chicks and of adult chickens was analysed. The process of embryonic development is accompanied by an increase in non-histone chromatin proteins and chromatin RNA, as well as in the phosphorus content of chromatin phosphoproteins. The amount of these components decreases in the livers of 1-day-old chicks and adults. Two-dimensional polyacrylamide gel electrophoresis of acid-soluble chromatin proteins showed an increase in the amount of the H1 histone in 19-day-old embryos and adult chickens. Non-histone proteins of embryo liver chromatin showed a high content of the fraction of Mr of about 40 000; this was not the case for adult chickens. The non-histone protein fraction of Mr of about 120 000, characteristic of adult chicken liver proteins, was not found in the livers of 12- and 15-day-old embryos. Non-histone chromatin proteins isolated from the livers of animals of different age exhibited also quantitative differences.  相似文献   
995.
Specific antibodies against the histone H2A from calf thymus were generated by injecting rabbits with complexes: histone H2A-RNA with a protein to RNA ratio of 3:1. In the microcomplement fixation assay the antibodies against the histone H2A from calf thymus immuno-reacted with the histone H2A from calf thymus but not with H2A from Physarum polycephalum. The histone H2A from calf thymus therefore appears to have an immunological determinant(s) which does not exist in H2A from Physarum polycephalum.  相似文献   
996.
A prospective controlled investigation in 134 consecutive outpatients compared the cytologic adequacy of sputum samples obtained by spontaneous and provoked expectoration. Inhalation of nebulized 10% sodium chloride was used for provoked expectoration. A significantly higher number of adequate samples was produced after provocation, as judged by the presence of alveolar macrophages (X2 = 5.63; p less than 0.02). The improvement in sample adequacy was limited to the nonsmokers and ex-smokers in the study. This result, together with the relatively high cost of cytologic sputum examinations, indicates that provoked expectoration should at least be applied to the collection of sputum samples from nonsmokers and ex-smokers.  相似文献   
997.
Degeneration of the knee joint and increase of anterior-posterior tibial displacement are resulting from total meniscectomy, especially in knees with anterior cruciate deficiency. Vascularisation of the meniscus was studied in 12 cadaver knees after latex injection of vessels. Vascularisation of the anterior and posterior horns was found to be much better than that of the body of meniscus. All vessels originated from the popliteal artery, but variably in importance, and formed the perimeniscal and subsynovial network. 11 peripheral meniscus tears (8 freshly injured, 3 ruptures older than 2 months) were repaired by refixation, followed by immobilisation for 6 weeks. Arthroscopy 3 months postoperatively showed complete healing of all tears. Clinical examinations--follow-up for 14 months--showed no signs of rerupture in any of the patients.  相似文献   
998.
The conidia of the endoparasitic fungus Meria coniospora (Deuteromycetes) had different patterns of adhesion to the cuticles of the several nematode species tested; adhesion in some species was only to the head and tail regions, on others over the entire cuticle, whereas on others there was a complete lack of adhesion. After adhesion, the fungus usually infected the nematode. However, adhesion to third-stage larvae of five animal parasitic nematodes, all of which carry the cast cuticle from the previous molt, did not result in infection. M. coniospora infected animal parasitic nematodes when this protective sheath was removed. Seven preparations of sialic acid (N-acetylneuraminic acid) gave three types of response in adhesion-infection of nematodes: (i) a significant reduction in conidial adhesions; (ii) no interference with adhesion, but a 10-day delay in infection; and (iii) a delay in infection by 2 to 3 days. The current results support previous findings indicating involvement of sialic acids localized on nematode cuticles in recognition of prey by M. coniospora.  相似文献   
999.
Pigs deriving from 150 breeding centres constituting a representative section of elite breeding herds (2496 Swiss Landrace pigs, 587 Swiss Large White pigs) were subjected to blood typing during the period 1981 to 1984. Production traits such as daily gain, feed conversion ratio, lean meat content and meat quality score were available to show the trend in these performance traits since 1978. Field data on the halothane reaction of 14 270 Swiss Landrace (SL) pigs were used to assess the porcine stress syndrome during the period 1978-1983. In SL pigs the frequency of the alleles Ha, PhiB and AdaA decreased significantly, and that of the Hc and PhiA increased during the period of the study. The frequency of the Ha allele dropped from 0.36 in 1981 to 0.20 in 1984, whereas the Hc allele rose from 0.22 to 0.37. In Swiss Large White (SLW) pigs, on the other hand, the frequency of the Ha allele increased constantly from 0.31 to 0.37 during this period. An initial frequency of 17.7% (1978) halothane reactors in SL pigs was lowered to 0.7% (1982) after five years of halothane testing. In SL pigs the meat quality scores improved regularly, whereas in SLW pigs it did not change very much. The percentage of PSE animals in the SL breed was reduced from 32.7% in 1978 to 7.1% in 1983. Because the Hal locus is associated with production traits such as meat quality, linkage disequilibria could explain the observed associations between the H and Phi types and production traits.  相似文献   
1000.
This study examines the effects of various degrees of chemical modification of low-density lipoprotein (LDL) on its catabolism by various cell types. Moderate glucosylation of LDL does not alter its interaction with the high-affinity receptor present on human fibroblasts at concentration of 5-2000 micrograms LDL-cholesterol/ml. Only heavily glucosylated LDL (more than 12 lysine residues glucosylated per apolipoprotein B) or LDL glucosylated in the presence of Na(CN)BH3, i.e., conditions not expected to occur in diabetes, inhibit receptor-mediated internalisation and degradation. Moderately glucosylated LDL is also readily recognized by cultured rat hepatocytes and porcine endothelial cells. Human monocyte-derived macrophages accumulate cholesteryl ester when incubated with acetylated LDL for 12 days but no enhanced cholesteryl ester formation was found when native or glucosylated LDL (3.3 lysines glucosylated per apolipoprotein B) were used.  相似文献   
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