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1.
Human CD4+ T cells differ in their expression of the leucocyte common antigen. Antibodies detecting certain forms (CD45RA and CD45RO) of this antigen have been used to identify and isolate subpopulations of the CD4+ T cells. These isolated subsets have been shown to have different abilities concerning lymphokine production and provision of help to B cells for Ig production. When these T-cell subsets were activated in vitro with polyclonal activators, the production. When these T-cell subsets were activated in vitro with polyclonal activators, the CD45RA+ cells lost this marker and gained the expression of CD45RO. This was true for all mitogens used in this report, i.e. accessory cell-dependent stimulation with SEA and accessory cell-independent activation with PMA or PHA. A correlation between proliferation and differentiation was observed, but this was probably not causative as stimulation with PMA in the absence of DNA synthesis resulted in the acquisition of CD45RO and loss of the CD45RA antigen. Moreover, cells proliferating vigorously for long periods of time expressed both markers at significant levels, which suggests that proliferation did not automatically result in complete loss of the CD45RA marker. The phenotypical differentiation was associated with a functional differentiation which induced the stimulated cells' ability to act as helper cells for Ig production and to produce gamma interferon (IFN-gamma). The results obtained in this study support the contention that the CD45RA+ cells are precursors of the CD45RO+ cells and that the two subsets represent different maturational stages of the same lineage.  相似文献   
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ABSTRACT. Enzyme-linked immunosorbent assay (ELISA) was used to measure the antibody response to Pseudomonas aeruginosa exotoxin A, elastase, alkaline protease and phospholipase C in patients with cystic fibrosis (CF). Only the chronically colonized patients showed elevated antibody titres to phospholipase C (22/22 patients), alkaline protease (16/22 patients), exotoxin A (15/22 patients) and elastase (5/22 patients). In a few patients where serial specimens were available, rising titres were recorded to all four antigens during periods of active infection. Antibiotic treatment resulted in decrease of titres against all four antigens, but only the anti-exotoxin A and anti-elastase titres decreased to normal levels. Titres to phospholipase C were the least influenced by antibiotic treatment. The results imply different roles for these exoproteins in chronic colonization versus active infection. The levels of P. aeruginosa antibodies to exoproteins could probably be used in monitoring treatment of patients with CF.  相似文献   
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Young adults (Md 24) and Adults (Md 41) were examined with respect to the distribution of occlusal contacts in molars, premolars and anterior teeth when exerting light and hard pressure respectively in the habitual intercuspal position. There was no difference between the right and left side and the number of contacts per tooth was low. In all groups of teeth there was a smaller number of contacts at light pressure. The lower number of contacts at light pressure in Adults when comparing with Young adults was related only to the anterior teeth. The increase of the number of contacts at hard pressure was greater for the anterior teeth than for the molars. In cases where there was a greater number of contacts present on one side, the distribution did not alter significantly when changing from light to hard pressure. Neither did the articulator-adjusted intercuspal position differ significantly in this respect from the clinically recorded intercuspal position at hard pressure. A further result was that about 50% of the individuals had 60% or more contacts on one side at light pressure. These findings stress the importance of meticulous care when performing occlusal adjustment, as the number of contacts per tooth is low and indicates the need for observing the difference between light and hard pressure.  相似文献   
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Release of hormones peri-operatively in patients with metastatic carcinoids may lead to severe circulatory and respiratory disturbances. Fourteen patients with liver metastases were studied during 16 operations with a modified neurolept anaesthesia in order to evaluate the central haemodynamic and respiratory functions as well as plasma serotonin levels. The premedication in five patients was supplemented with levopromazine. During the 11 operations performed on patients not pretreated with levopromazine, no major significant fluctuations in circulatory or respiratory functions were recorded although big variations in serotonin plasma levels were measured. In the patients treated with levopromazine, however, significant changes were observed in heart rate, mean pulmonary artery pressure, cardiac index, and left and right ventricular stroke work especially during flushing episodes. However, these changes did not correlate with the changes in plasma serotonin levels. Modified neurolept anaesthesia without levopromazine pretreatment combined with careful monitoring seems to be a safe procedure for carcinoid patients. Using this type of anaesthetic procedure only one major complication occurred in connexion with 16 major operations and then in the postoperative period.  相似文献   
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R. J. ERICSSON 《Andrologia》1977,9(1):111-114
Human sperm progressively motile and free of seminal debris can routinely be isolated, during a 1.5 hour process, from semen of normal and subfertile men. Serum albumin, in a vertical column, acts to filter sperm based on their swimming abilities of forward progression. The isolated sperm constitute a population that can be inseminated as an aid to male subfertility or, to enhance the chances of sperm survival upon deep-freeze preservation. The latter use resulted in twice the survival rate, based on sperm motility, of random populations of control sperm.

Zusammenfassung


Progressiv bewegliche menschliche Spermatozoen, die frei sind von anderen Sperma-bestandteilen, können routinemäßig in einem 1 1/2 stündigen Vorgang aus dem Sperma von normalen und subfertilen Männern isoliert werden. Serum Albumin, in einer verti-kalen Säule, wird dazu benutzt, um die Spermatozoen aufgrund ihrer Schwimmfähig-keit und ihrer progressiven Motilität zu filtrieren. Die isolierten Spermatozoen stellen eine Population dar, die als Hilfe oder als Therapeutikum bei männlicher Subfertilität dienen kann oder das Äberleben der Spermatozoen nach Aufbewahrung unter Gefrier-bedingungen verbessert. Diese Anwendung ergab eine Äberlebensrate (gemessen an der Motilität), die doppelt so hoch war, wie bei zufällig ausgewählten Populationen von Kontrollsperma.  相似文献   
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