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P Avril R Ducroc B Garzon E Moreau F Hervatin P Millet J P Geloso 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1986,303(18):739-742
Sensitivity of the developing rat stomach to histamine (HA) was examined on isolated gastric mucosae of rats of various ages from the fetal to adult periods. Spontaneous acid secretion in mu eq/h.cm2 occurred at all the ages studied, at a basal rate of 0.45 +/- 0.07 in fetuses to 0.22 +/- 0.03 (day 5), 0.11 +/- 0.04 (day 10), 0.12 +/- 0.04 (day 12), 0.22 +/- 0.08 (day 16) and 0.33 +/- 0.04 (adults). In the fetal rats as in the adults, marked responses to respectively 10(-5) and 10(-4) M HA were demonstrated. The H2-receptor antagonist cimetidine diminished HA-induced secretion by 66 and 57% in fetuses and adults respectively. Between these two stages (from days 5 to 12), basal secretion and the response to HA dropped significantly. On day 21 of gestation, as well as on the critical days 5 and 12 after parturition, db-cAMP (10(-4) M) caused maximal stimulation of acid secretion. These results indicate that the development of responsiveness to HA in the rat is biphasic. They suggest that after birth, the H2-receptor adenylate cyclase system undergoes major modifications which might lead to the complete lack of responsiveness to HA by day 12. 相似文献
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A C Srivastava A J Pinching M W Adler R Robertson R Higgs 《BMJ (Clinical research ed.)》1987,294(6570):495-496
Dr A C Srivastava has written to us to describe a case that raises the suggestion that people infected with the human immuno-deficiency virus (HIV) should carry identity cards. We asked two physicians, a general practitioner working with patients with the acquired immune deficiency syndrome (AIDS), and a general practitioner with a special interest in medical ethics to respond to the broad issues raised by Dr Srivastava''s letter. 相似文献
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Eileen M. Proctor Judith L. Isaac-Renton William B. Robertson William A. Black 《CMAJ》1985,133(9):876-878
A survey was done of Canadians who had been interned by the Japanese during World War II to assess the prevalence of latent infection with Strongyloides stercoralis in this group. Packages containing three mail-in kits and a questionnaire were sent to 992 men, 694 (70%) of whom responded. Larvae were found in the stool specimens of four of the respondents. Examination of stool specimens after formalin-ether concentration was the most successful method of detecting Strongyloides larvae. The Baermann concentration technique yielded negative results in all four men. Three of the four cases of strongyloidiasis were detected after sampling of three fecal specimens. In the fourth case additional specimens were requested on the basis of data derived from the questionnaire. The most frequently cited clinical manifestations were abdominal pain, weight loss, diarrhea and rashes. 相似文献
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Abstract— An enzyme radiochemical assay for p -octopamine, m -octopamine (norphenylephrine) and phenylethanolamine based on the N -methylation of these amines by the enzyme phenylethanolamine N -methyl transferase ( S -adenosyl- l -methionine: phenylethanolamine N -methyl transferase (EC 2.1.1.28) has been developed. [3 H]Methyl- S -adenosyl- l -methionine was used as methyl donor. The reaction products are converted to their dansyl derivatives and separated by TLC in three different solvent systems prior to liquid scintillation counting. The method exhibits a sensitivity of less than 10 pg for each amine and is suitable for the measurement of endogenous p -octopamine levels in mammalian brain. The highest levels of p -octopamine were found in the hypothalamus (3.4 ng/g) but despite the sensitivity of the assay, neither phenylethanolamine nor m -octopamine could be detected. After MAO inhibition, however, both of these amines were found to be present. p -Octopamine was increased substantially in all brain regions following the administration of an MAO inhibitor, whereas pretreatment with reserpine produced a significant decrease in the hypothalamus. 相似文献
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The myc family of proto-oncogenes consists of several members that possess regions of sequence homology and some have known similarities in structure and function. We have isolated an 8.8-kb EcoRI fragment from a human genomic library by hybridization to a 28-base oligonucleotide probe derived from a region of the second exon of MYC, which is highly conserved in the myc gene family. Sequence analysis of this myc-like (MYCLK1) DNA fragment has revealed the existence of a region with 85% homology to the 28-base oligonucleotide probe. An open reading frame of 207 nucleotides containing the region of homology was found. We have mapped MYCLK1 to human chromosome 7 at band p15 by chromosome in situ hybridization; this site is distinct from the map location of previously characterized myc genes. Whether MYCLK1 represents a new functional member of the myc family of proto-oncogenes remains to be determined. 相似文献