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371.
F. N. Johnson 《Cellular and molecular life sciences : CMLS》1976,32(10):1350-1351
Summary Arguments presented against a hypothesis of the mechanisms underlying the behavioural effects of lithium ions are examined and found to be inadequate in a number of important respects, including some of a logical nature. 相似文献
372.
J. Dunn R. Peppler M. Hess D. C. Johnson 《Cellular and molecular life sciences : CMLS》1976,32(10):1342-1344
Summary Intact and TPTx animals showed the expected afternoon increase in serum LH, FSH and prolactin levels. But the afternoon increase in serum LH levels in TPTx rats was less than that observed for intact animals (p<0.01). Neither serum prolactin nor FSH levels were altered by TPTx.The excellent technical and secretarial assistance ofS. Hemelt andD. Landman is gratefully acknowledged. 相似文献
373.
Biological processes frequently require the formation of multi-protein or nucleoprotein complexes. Some of these complexes have been produced in homogeneous form, crystallized, and analysed at high resolution by X-ray crystallography (for example, see refs 1-3). Most, however, are too large or too unstable to crystallize. Individual components of such complexes can often be purified and analysed by crystallography. Here we report how the coordinated application of cryoelectron microscopy, three-dimensional image reconstruction, and X-ray crystallography provides a powerful approach to study large, unstable macromolecular complexes. Three-dimensional reconstructions of native cowpea mosaic virus (CMPV) and a complex of CPMV saturated with a Fab fragment of a monoclonal antibody against the virus have been determined at 23 A resolution from low-irradiation images of unstained, frozen-hydrated samples. Despite the nominal resolution of the complex, the physical footprint of the Fab on the capsid surface and the orientation and position of the Fab have been determined to within a few ?ngstroms by fitting atomic models of CPMV4 and Fab (Kol)5 to reconstructed density maps. 相似文献
374.
Two classes of molecules often released after the interaction of T lymphocytes, macrophages and antigen are B-cell maturation factors (BMF)1-3 and immune (gamma) interferon (IFN-gamma)4-7. BMFs directly induce the maturation of resting B lymphocytes to the state of active immunoglobulin secretion, while IFN-gamma is defined by the reduction of viral infectivity in vitro. However, interferons have been shown to have a variety of effects and they have also been reported both to increase and decrease B-cell differentiation in intact animals and complex cellular mixtures in vitro. Here we show that murine IFN-gamma produced by recombinant DNA technology shows similar biological effects to BMFs from two other sources. All three preparations induce immunoglobulin secretion by both normal resting murine splenic B cells and the comparable B-cell tumour line WEHI-279.1 (refs 1, 3). IFN-gamma and the other two BMFs are not identical, however, as anti-IFN-gamma antibodies block the effects on B cells of IFN-gamma, but not those of the other two lymphokines. IFN-gamma may be one of several molecules with a direct role in driving the maturation of resting B cells to active immunoglobulin secretion. 相似文献
375.
The data suggest that rats genetically inbred to be hypertensive (SHR) are less able to compensate for hemorrhage and shock than their normotensive controls (WKY). Two reasons for this genetic dysfunction are: 1) SHRs seem to depend more on innervated alpha 1 than noninnervated alpha 2 adrenoreceptors for vasoconstriction; and 2) the vascular smooth muscle hypertrophy noted in SHRs may interfere with effective vasoconstriction. 相似文献
376.
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378.
B. Stavric W. J. Johnson S. Clayman R. E. A. Gadd A. Chartrand 《Cellular and molecular life sciences : CMLS》1976,32(3):373-374
Summary Fructose administration to the uricase inhibited rat produces a very marked elevation in serum urate levels. 相似文献
379.
380.
Allotransplantation of fresh, 1 or 2 week cultured parathyroid glands from Wistar rats (AgB2) to Fischer rats (AgB1) resulted in prompt rejection of the transplant in the muscle site; whereas transplantation into the adrenal site offered slightly prolonged survival, suggesting that the latter is a privileged transplantation site. 相似文献