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41.
应用显微分光光度计测定15例鼻咽癌19处癌旁病变的上皮细胞核DNA含量并与浸润癌相比较。中、重度异型增生上皮细胞核DI及超过2.5c细胞的百分数处于单纯增生+轻度异型增生与浸润癌之间,3组DI及超过2.5c细胞的百分数差异显著。中、重度异型增生以非整倍体为主,其细胞核DNA含量组方图相似于浸润癌。从细胞核DNA含量角度来看,中、重度异型增生是重要的癌前病变。  相似文献   
42.
Summary The 275 Purkyn cells identified by the criteria of the previous paper have been investigated with respect to their role as units integrating the input to the anterior lobe from various limb nerves. The discharges from single Purkyn cells have been studied in lightly anesthetized (pentothal) or in decerebrate unanesthetized cats, there being averaging usually of 128 responses in the form of post-stimulus time histograms and cumulative frequency distributions.Single Purkyn cells exhibited a wide variation in their responses to the diverse inputs from the various afferent nerves. Attention was focussed on excitatory and inhibitory responses evoked by mossy fibers with a short latency, usually 10–15 msec for hindlimb afferents. With most Purkyn cells these responses were predominantly evoked from cutaneous nerves, low threshold fibers being particularly effective. A few Purkyn cells were preponderantly excited by afferent volleys from muscle nerves, but there was a large group with a mixed input from cutaneous and muscle nerves. Graded strengths of stimulation of muscle nerves showed that sometimes group I volleys were prepotent, but other Purkyn cells were selectively excited by group II volleys. Though sometimes the afferent volleys from antagonistic muscles had a reciprocal action on a Purkyn cell, as on a motoneurone, it was more common to find similar actions. Also convergence of inputs from forelimb and hindlirnb nerves, both cutaneous and muscular, was not uncommon, particularly in marginal areas between hindlimb and forelimb zones. A special design feature is the convergence onto a Purkyn cell of mossy fiber and climbing fiber inputs evoked by the same afferent volley. This convergence was of particular interest along the parasagittal strip of hindlimb climbing fiber distribution in lobule V.It was not possible to translate the observations into some map of the cerebellar cortex on which are marked the territorial distributions from the various limb afferent nerves. Rather, there was an ill-defined patchy character, closely adjacent Purkyn cells often receiving very different subsets of the total input from the various limb nerves. The unitary integrations accomplished by the individual Purkyn cells are further integrated when their axons converge onto and inhibit the neurones of the cerebellar nuclei, and this integration by convergence would occur in each successive relay on the output pathways from the cerebellum.It is pointed out that the experimental findings on the integrative action of the individual Purkyn cells provide basic information for attempts to construct models simulating cerebellar performance and control.Post-Doctoral Fellow NINDS (1F2NB40, 545101 NSRB).Post-Doctoral Fellow UHF Grant No. FTF-3-UB-70.  相似文献   
43.
Journal of Clinical Immunology - The objective of this study was to characterize interleukin-1 receptor antagonist (IL-1ra) and interleukin-1β (IL-1β) production by human peripheral blood...  相似文献   
44.
45.
Summary Hemoglobin (Hb) M-Saskatoon, a variant of methemoglobin, is characterized by mild hemolysis. It is caused by the substitution of a histidine by a tyrosine at the 63rd amino acid residue of the -globin chain. Amplification and sequence analysis of genomic -globin DNA from an Indonesian boy diagnosed as having the more severe disease thalasemia demonstrated the presence of a C to T transition at nucleotide 473 in one of the two -blogin genes resulting in a histidine to tyrosine substitution at 63rd residue. This amino acid change matched with that reported in Hb M-Saskatoon. This nucleotide change abolished a recognition site for the restriction endonucleaseNlaIII.NalIII digestion of the corresponding -globin DNA amplified from the patient's parents indicated that the mutation was inherited through from his mother. This result shows that the world-wide distribution of Hb M-Saskatoon extends to Indonesia, where it was not previously identified. Possible causes of the unusually severe symptoms observed in the case are discussed.  相似文献   
46.
A procedure is described for standardising the determination of adenosine 5-triphosphate and phosphocreatine concentration ([ATP] and [PC], respectively, in absolute arbitrary units) in human muscle by nuclear magnetic resonance (NMR) spectroscopy. The individual 31phosphorus (21P)-NMR spectra obtained on equal hemispherical tissue volumes (muscle plus skin and fat) were corrected for the thickness of the skin and of the subcutaneous fat. The volumes investigated were standardised using an external reference. The procedure described made possible the comparison of high energy phosphate concentrations among different subjects. It was applied to the assessment of [ATP] and [PC] in four groups of sedentary subjects (children, and adults aged 20–35, 35–50 and over 50 years), and in a group of athletes (volleyball players). The [ATP] and [PC] were not statistically different in the groups investigated.  相似文献   
47.
The adrenergic control of vascular smooth muscle was compared in young and adult rabbits using a variety of in vitro techniques. Norepinephrine (NE) content and accumulation of 3H-NE were not different in blood vessels from the two age groups. In contrast, stimulation-evoked release of endogenous NE was reduced by 40–60% in vessels from the aged animals. Functional studies of smooth muscle contractions were carried out using isolated ring segments of the ear artery. There were no differences in the resting force-response relationship between vessels from young and adult rabbits. Maximum contractile responses to nerve stimulation, NE or KCl were not different in vessels from the two age groups, nor was the NE ED50. However, blockade of the neuronal uptake system with desmethylimipramine produced a greater shift in the NE concentration-response curve in vessels from the young animals compared to the shift in vessels from adult animals. This observation reflects a decline in neuronal NE uptake with age. Although maximal contractile responses to transmural nerve stimulation at 16 Hz were unchanged, responses to stimulation at lower frequencies were reduced in vessels from adult rabbits, an effect which was also enhanced when an antagonist of neuronal uptake was present. Thus, there is a decline in function of adrenergic nerves in adult animals, reflected in a decrease in stimulation-evoked NE release and a decrease in norepinephrine uptake revealed by functional studies. These two effects tend to balance each other, so that there is a small decrease in contractile response to adrenergic nerve stimulation which is exacerbated when neuronal uptake mechanisms are blocked.  相似文献   
48.
We report three possibly disease-causing point mutations in one of the inner-ear-specific genes, KIAA1199. We identified an R187C mutation in one family, an R187H mutation in two unrelated families, and an H783Y mutation in one sporadic case of nonsyndromic hearing loss. In situ hybridization indicated that the murine homolog of KIAA1199 mRNA is expressed specifically in Deiters cells in the organ of Corti at postnatal day zero (Pn) P0 before the onset of hearing, but expression in those cells disappears by day P7. The signal of KIAA1199 was also observed in fibrocytes of the spiral ligament and the spiral limbus through to P21, when the murine cochlea matures. Thus, the gene product may be involved in uptake of potassium ions or trophic factors with a particular role in auditory development. Although the R187C and R187H mutations did not appear to affect subcellular localization of the gene product in vitro, the H783Y mutation did present an unusual cytoplasmic distribution pattern that could underlie the molecular mechanism of hearing impairment. Our data bring attention to a novel candidate for hearing loss and indicate that screening of mutations in inner-ear-specific genes is likely to be an efficient approach to finding genetic elements responsible for deafness.Nucleotide sequence data reported herein are available in the DDBJ/EMBL/GenBank databases; for details, see the electronic eatabase section of this article.  相似文献   
49.
Summary The a mating pheromones synthesized in three Saccharomyces yeasts (S. cerevisiae, S. kluyveri, and S. exiguus) displayed interspecific actions on the a cells of all three species despite the fact that the amino acid sequences of all three pheromones are different. Mating between species, however, did not occur. The interspecifie pheromone — a cell reaction was not necessarily more effective than the interspecific one. Deceased on March 28, 1987  相似文献   
50.
Zusammenfassung Die BKS und 12 Plasmaproteine von 21 Kranken mit unterschiedlichen Krankheiten wurden statistisch miteinander verglichen. Dabei ergaben sich positive Korrelationen zwischen der BKS und dem sauren 1-Glykoprotein und der BKS und dem 1-Antitrypsin, eine negative Korrelation zwischen der BKS und dem Transferrin. Außerdem korrelierten das saure 1-Glykoprotein und das 1-Antitrypsin sowie das saure 1-Glykoprotein und das Transferrin miteinander. Bei der Deutung dieser Ergebnisse müssen einerseits Gemeinsamkeitskorrelationen in Betracht gezogen werden, zum anderen die Möglichkeit, daß zwischen bestimmten Proteinmustern und der BKS Zusammenhänge bestehen.  相似文献   
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