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21.
Serum complement levels were assayed in 26 patients with disseminated cancer, who received immunotherapy with infusion of C. parvum. Complement activation, indicated by the consumption of C3 or C4 or both, was found in 46% of the patients. Serum samples showed direct correlation between decreased C3 and conversion of C3 proactivator, whereas such conversion did not occur when C4 alone was decreased. It is concluded that the bypass (properdin) pathway was activated in patients in whom C3 consumption was detected, while the classical (C1) pathway was activated in the patients with C4 consumption unaccompanied by C3 decrease. Direct correlation was observed between delayed cutaneous hypersensitivity reactions to recall antigens and the incidence of C. parvum-associated complement activation.  相似文献   
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The indices of glucocorticoid and androgen activity in the adrenal cortex (the level of circulating eosinophils, the daily urine excretion of 17 OCS and 17 CS) and the functional reserve after an ACTH loading was studied in 2 groups of patients with disorders of cerebral circulation under 45 years of age (247 cases) and over 55 (234 cases). In the acute period of a cerebral stroke there was an increase of the glucocorticoid activity which was more definitely expressed in the younger group and a certain inhibition of the androgen function seen mainly in the older group. In transient disorders of cerebral circulation significant age difference in the functioning of the adrenal cortex was not established. In the period following a stroke the established and potential reserves of the adrenocortical glands were distinctly decreased in patients above 55 years and practically unchanged in the younger group.  相似文献   
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Two alkylating (cyclophosphamide and 036.5122 Asta) and two antiproliferative agents (6-mercaptopurine and azathioprine) have been compared for their immuno-suppressive potency on the primary and secondary humoral immune response of mice. If equitoxic dosages of the respective drugs are compared, the alkylating agents proved to be of much higher immunosuppressive potency than the antiproliferative agents. In non toxic dosages alkylating agents were able to completely inhibit a primary or secondary immune response, whilst a similar effect with antiproliferative drugs could not be obtained even within toxic dose ranges. Induction of immunological tolerance was possible only by use of the alkylating agents. The significance of these comparative studies is discussed in view of the frequent use of the tested drugs in clinical immunosuppression.  相似文献   
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X-ray fiber diffraction studies of satellite DNAs from Gecarcinus lateralis, Drosophila virilis and Mus musculus, all of which have highly repetitious base sequences but with different degrees of sequence complexity, reveal only classical polynucleotide duplex structures in contrast to some highly repetitious synthetic DNAs.  相似文献   
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Ceftriaxone has a very high plasma protein binding (up to 98%) that is saturable and decreases with higher concentrations. This high protein binding results in high concentrations in plasma that are frequently related to the anti-infective activity. However, because only the free fraction of the drug is pharmacologically active and most of the infections are located in the tissues, it is more relevant to evaluate unbound concentrations in the interstitial space. Plasma and tissue pharmacokinetics of ceftriaxone in rats after single intravenous administration were investigated at two different concentrations (50 and 100 mg/kg). Both plasma and tissue samples were taken simultaneously from the same animal and analyzed by reversed-phase high-performance liquid chromatography. Free tissue levels in the thigh muscle were measured by microdialysis. The concentration in plasma is much higher than the free concentration in tissue. After determination of nonlinear protein binding by microdialysis and including these parameters in the pharmacokinetic model, it is possible to predict free concentrations in the interstitial space from plasma levels for any given dose.  相似文献   
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