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681.
This paper reviews selected biochemical and functional studies characterizing B lymphocytes from patients with chronic lymphocytic leukemia. When compared to B lymphocytes from the circulation of normal subjects, a number of differences are noted. Functionally, the CLL B lymphocyte is impaired in mitogen response, cap formation following attachment of multivalent ligands, and the density of surface immunoglobulins. It also differs from normal in the content of the ectoenzyme 5' nucleotidase, which is often decreased, and the concentration of ascorbic and dehydroascorbic acid, which are markedly elevated in these cells. The level of tocopherol is decreased. CLL and normal B lymphocytes are more vulnerable than T lymphocytes to the toxic effect of H2O2. This sensitivity is Ca2+ dependent and inhibited by nanomolar concentrations of nonsteroidal antiinflammatory agents. These studies identify the human B lymphocyte as a cell that should be a suitable target for selective killing by H2O2. 相似文献
682.
In 5- to 6-, 7- to 8-, and 10- to 11-year-old children, age-related features of the effects of former experience on the recognition of emotional facial expressions were found using a cognitive set model. In five- to six-year-old children, an inert set to an angry facial expression was formed and expressed during testing as a large number of erroneous recognition of facial expressions of the perseverative type (assimilative) illusions. Set plasticity was increased in seven- to eight-year-old children and the number of assimilative illusions decreased. In 10- to 11-year-old children, the cognitive set was similar to adults in terms of its plasticity and a ratio of assimilative and contrast illusions. Changes in the spatial synchronization of electrical potentials in the ??- and ??-frequency bands were observed in all age groups, mainly during set formation. In all age groups, we observed a correlation between the bioelectrical data and the effects of former experience on the recognition of facial expression. Based on the data on the coherence of the potentials of the ??- and ??-ranges we propose age-related changes in the involvement of the cortico-hippocampal and fronto-thalamic functional systems of integration of brain activity in organizing the sets to emotionally negative facial expressions. 相似文献
683.
Malcolm A. Bagshaw Harold M. Schneidman Eugene M. Farber Henry S. Kaplan 《The Western journal of medicine》1961,95(5):292-297
Ionizing radiation in the form of x-ray therapy is the best modality of treatment available at the present time for single, isolated lesions of mycosis fungoides. However, for generalized mycosis fungoides, generalized x-ray therapy is technically difficult and dangerous. It is now possible to employ electron beam therapy for generalized mycosis fungoides, using energies which confine the dose to the superficial layers of the skin and thus avoid hematopoietic injury. A technique for wide field electron beam therapy has been developed for this purpose which has been effective and well tolerated in limited trials to date. 相似文献
684.
Anaphylactic reactions following the injection of penicillin or other antibiotics have increased greatly during the past several years. These untoward reactions to penicillin were infrequent during the first nine years of penicillin therapy and there can be no doubt that hypersensitivity to these drugs is developing in many people. Therefore promiscuous use of them is to be condemned. It is safer not to use antibiotics parenterally in patients with allergic conditions such as bronchial asthma. The further use of a particular antibiotic should be avoided if the patient has previously shown any hypersensitivity to that drug.A questionnaire was answered by more than 1,000 California physicians who reported that over 300 patients had severe anaphylactic reactions from parenteral penicillin and streptomycin. There were seven deaths.Since the antibiotics should still be used when needed, prevention of anaphylaxis is of fundamental importance. The frequency of these reactions can be greatly reduced by the use of antihistaminic solutions combined with the antibiotics. Treatment of these shock-like reactions demands the prompt administration of epinephrine intramuscularly, antihistaminic solutions intravenously and oxygen. 相似文献
685.
Mice carrying the autosomal recessive rd gene experience total degeneration of the photoreceptor cells of the retina by 3 to 4 weeks of life. Biochemical studies of the rd retina have demonstrated a lesion in cyclic guanosine monophosphate (cGMP) metabolism due to depressed rod-specific cGMP-phosphodiesterase (cGMP-PDE) activity. The depressed activity could result from, among other things, a lesion in the cGMP-PDE enzyme itself or in any of a number of proteins in the rod that regulate it. We have used a cDNA clone for the alpha-subunit of bovine rod transducin (T alpha 1) to map the corresponding gene, Gnat-1, to mouse chromosome 9 with a panel of Chinese hamster-mouse somatic cell hybrid DNAs. Transducin, a heterotrimeric G protein, is involved in the stimulation of cGMP-PDE when light hits the rod photoreceptors. Since the primary defect in rd disease occurs in a gene(s) on mouse chromosome 5, our results suggest that Gnat-1 is not the rd gene. 相似文献
686.
687.
B. H. Forman E. Marban R. D. Kayne N. M. Passarelli S. N. Bobrow V. A. Livolsi M. Merino M. Minor L. R. Farber 《The Yale journal of biology and medicine》1979,52(2):181-189
A 51-year-old female was diagnosed preoperatively to have a pheochromocytoma producing ACTH. This diagnosis was based upon her paroxysmal hypertension, hyperpigmentation, and hypokalemia. Elevated levels of serum and urine corticosteroids, plasma ACTH, urinary VMA, and catecholamines fell after a right adrenal pheochromocytoma was removed. Subsequently this tumor was found to have a high content of ACTH. Review of the literature indicates a mortality rate of 57% for this syndrome. Proper preoperative recognition and management can result in total cure. 相似文献
688.
689.
690.
R N Lolley B M Brown D B Farber 《Biochemical and biophysical research communications》1977,78(2):572-578
Protein kinase activity of isolated rod outer segments from bovine retinas is activated by cGMP when in a soluble form, and it is cyclic nucleotide independent when associated with the rod outer segment membranes. The soluble protein kinase phosphorylates in a cyclic nucleotide-dependent manner only a single endogenous protein with an apparent molecular weight of 30,000 daltons. The 30,000-dalton phosphoprotein is localized specifically in the visual cells of the retina. It is proposed that the light-induced changes in cGMP levels that occur in rod outer segments are linked by the cyclic nucleotide-dependent protein kinase to alterations in the content of the 30,000-dalton phosphoprotein. 相似文献