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71.
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Increased Sensitivity of Lymphocytes from Atopic Individuals to Histamine-Induced Suppression 总被引:4,自引:0,他引:4
Histamine depressed lymphocyte reactivity to phytohemagglutinin and, to a lesser degree, concanavalin A, when administered simultaneously with mitogen to lymphocyte cultures. Addition of histamine at later times to the cultures appeared to have a slightly enhancing effect on the lymphocyte response. Stimulation of lymphocytes with pokeweed mitogen was in some cases enhanced, even by high concentrations of histamine. Lymphocytes from atopic individuals were more sensitive to the inhibitory effect of histamine than lymphocytes from nonatopic individuals. The sensitivity appeared age-dependent, but within each age group histamine evoked significantly more suppression on lymphocytes from atopic than from nonatopic individuals. The possibility that the altered reactivity of lymphocytes to histamine, which appears to be associated with atopic allergy, is of pathogenic importance, is discussed, and a hypothesis for the development of atopic disease is proposed. 相似文献
73.
Predominance of null mutations in ataxia-telangiectasia 总被引:15,自引:4,他引:15
Gilad S; Khosravi R; Shkedy D; Uziel T; Ziv Y; Savitsky K; Rotman G; Smith S; Chessa L; Jorgensen TJ; Harnik R; Frydman M; Sanal O; Portnoi S; Goldwicz Z; Jaspers NG; Gatti RA; Lenoir G; Lavin MF; Tatsumi K; Wegner RD; Shiloh Y; Bar-Shira A 《Human molecular genetics》1996,5(4):433-439
Ataxia-telangiectasia (A-T) is an autosomal recessive disorder involving
cerebellar degeneration, immunodeficiency, chromosomal instability,
radiosensitivity and cancer predisposition. The responsible gene, ATM, was
recently identified by positional cloning and found to encode a putative
350 kDa protein with a Pl 3-kinase-like domain, presumably involved in
mediating cell cycle arrest in response to radiation-induced DNA damage.
The nature and location of A-T mutations should provide insight into the
function of the ATM protein and the molecular basis of this pleiotropic
disease. Of 44 A-T mutations identified by us to date, 39 (89%) are
expected to inactivate the ATM protein by truncating it, by abolishing
correct initiation or termination of translation, or by deleting large
segments. Additional mutations are four smaller in-frame deletions and
insertions, and one substitution of a highly conserved amino acid at the Pl
3-kinase domain. The emerging profile of mutations causing A-T is thus
dominated by those expected to completely inactivate the ATM protein. ATM
mutations with milder effects may result in phenotypes related, but not
identical, to A-T.
相似文献
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Breast cancer detection: one versus two views 总被引:2,自引:0,他引:2
Mammographic examinations of 169 patients with 172 biopsy-proved carcinomas, and of 194 healthy subjects, were interpreted independently and retrospectively by three experienced mammographers, initially as single-view oblique examinations and 6 months later as two-view oblique-cephalocaudal examinations. For the single-view examinations of the cancer patients, 67% of the cancers were correctly recommended for biopsy, additional views were requested for 23%, and a "negative" interpretation was made for 10%. For the single-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were recommended for 32%. For the two-view examinations of women with cancer, 80% of the cancers were correctly recommended for biopsy, additional views were requested for 4%, and a "negative" interpretation was made for 16%. For two-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were requested for only 5%. The authors conclude that single-view screening should not be performed, because it would lead to an excessive number of "call-back" examinations of healthy patients, producing additional cost and anxiety that would outweigh any theoretical benefit. 相似文献
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Dane Christina Daoud MD Elena M. S. Cartagena MD MSc Katherine J. P. Schwenger RD PhD Nicha Somlaw MD Leah Gramlich MD Scott Whittaker MD David Armstrong MD Brian Jurewitsch PharmD Matreyi Raman MD Donald R. Duerksen MD James D. McHattie MD Johane P. Allard MD 《JPEN. Journal of parenteral and enteral nutrition》2022,46(2):348-356
80.
Specific nutrition and metabolic characteristics of critically ill patients with persistent COVID-19