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171.
172.
Electron microscopic examination of gonads of Drosophila melanogaster with different genotypes, including a metafemale 3X;2A and an intersex XXY;3A have revealed that the formation of synaptonemal complexes is controlled by the genic balance, i.e., the ratio of X chromosomes to autosomes. The Y chromosome is not involved in the genetic control of the formation of precursors of the central element of synaptonemal complexes in males, nor does it disturb their formation in XXY females. Hyperploidy for sections 1-3A and 18A-20 of the X chromosome does not lead to the appearance of synaptonemal complexes in males and does not interfere with their formation in females. Females hyperploid for extensive regions of the X chromosome (sections 1-11A, 11A-20, and 8C-20) are fertile and show apparently normal formation of synaptonemal complexes. Hyperploidy for sections 8C-11A of the X results in a sharp decrease in the viability of females, in abnormal differentiation of ovary cells, and in the lack of synaptonemal complexes. These data suggest a possible important role for the sections 8C-11A in the genic balance controlling the formation of synaptonemal complexes in D. melanogaster. The lack of synaptonemal complexes in hypoploid females may be the result of abnormal cell differentiation in gonads.  相似文献   
173.
Seven polymorphic loci mapping to human chromosomal region 11q22-qter   总被引:11,自引:0,他引:11  
Seven polymorphic loci that map to human chromosomal region 11q22-qter are revealed by DNA probes isolated from a chromosome-specific phage library constructed from a human X mouse somatic cell hybrid that has retained an 11q;16q translocation as the only human DNA. Three probes, each of which reveals a two-allele polymorphism, and four probes, each of which detects two linked RFLPs, have been characterized. Using a somatic cell hybrid mapping panel that divides 11q into four discrete sections, the seven clones have been localized to specific chromosomal regions. Localization of one of the clones has been confirmed and refined by in situ hybridization.  相似文献   
174.
FSH beta, as well as LH beta, and alpha-subunit mRNA levels were examined in the pituitary glands of male rats after sex steroid replacement at various times (7, 28, or 90 days) after orchiectomy. Testosterone propionate, dihydrotestosterone propionate, or 17 beta-estradiol benzoate (E) were administered daily for 7 days before killing, to assess the role of different gonadal steroids on gonadotropin subunit mRNA levels. Subunit mRNAs were determined by blot hybridization using rat FSH beta genomic DNA, and alpha and LH beta cDNAs. At all time points, alpha and LH beta mRNAs increased after gonadectomy and fell toward normal levels with either androgen or estrogen replacement. FSH beta mRNA levels increased variably postcastration: 4-fold at 7 days, 2-fold at 28 days, and 4- to 5-fold at 90 days. Although E replacement uniformly suppressed FSH beta mRNAs, neither testosterone propionate nor dihydrotestosterone propionate administration suppressed FSH beta mRNA levels at any time point after orchiectomy. These data demonstrate that there is a relative lack of negative regulation of FSH beta mRNA levels by androgens in a paradigm in which E administration results in marked negative regulation of FSH beta mRNA levels. Thus, in the male rat, estrogens negatively regulate all three gonadotropin subunit mRNA levels while androgens negative regulate LH beta and alpha-subunit but fail to suppress FSH beta mRNAs.  相似文献   
175.
Summary Anatomical evidence is presented for an interaction of ACTH1–39 immunostained fibers and a specific population of hypothalamic paraventricular (PVN) neurons; these neurons project to the dorsal vagal complex (DVC) of brainstem medulla. Bilateral injection of 10% HRP-WGA into DVC is incorporated into nerve terminals and transported retrogradely to cell bodies in the parvocellular subdivision of PVN, as revealed by standard HRP-WGA histochemistry or antibody to wheatgerm agglutinin followed by immunocytochemical techniques. Labeled cells are localized predominantly in the ventral portion of the caudal medial parvocellular subdivision and ventrolaterally in the posterior subnucleus of PVN. Few labeled cells are seen in the anterior parvocellular PVN, rostrally in the medial parvocellular component and in the dorsal cap. HRP-WGA cells are rarely observed in the magnocellular divisions of PVN. Dual-staining immunocytochemical-retrograde tracing techniques in the same tissue section demonstrate ACTH1–39 fibers in intimate anatomical proximity to parvocellular PVN neurons that project to DVC. It is suggested that this interaction may partially account for the known cardiovascular effects of opiocorins and supports the role of the paraventricular nucleus in hypothalamie integration and modulation of cardiovascular control.  相似文献   
176.
Cellular adaptation to ethanol   总被引:1,自引:0,他引:1  
  相似文献   
177.
A series of novel hGRF(1-29)-NH2 analogs were synthesized and biotinylated. The immunological and biological activities of these analogs were then characterized. To distance the biotin moiety from the putative bioactive core, a C-terminal spacer arm consisting of -Gly-Gly-Cys-NH2 (-GGC) was added to hGRF(1-29)-NH2 (hGRF29) and analogs, with subsequent biotinylation performed at the cysteine residue. Neither addition of the C-terminal spacer arm nor biotinylation affected affinity of these analogs for GRF antibody. Relative to hGRF(1-44)-NH2 (hGRF44: potency = 1.0), the biotinylated analogs were equipotent in vitro to their nonbiotinylated, parent compounds: [desNH2Tyr1,D-Ala2,Ala15]hGRF29-GGC-(tpBiocyt in)-NH2 (4.7) = [Ala15]hGRF29-GGC-(tpBiocytin)-NH2 (3.9) greater than hGRF29-GGC-(tpBiocytin)-NH2 (0.8). Based upon cumulative GH release data in vivo (0-60 min postinjection), [desNH2Tyr1,D-Ala2,Ala15]hGRF29-GGC-(tpBiocyt in)-NH2, [Ala15]hGRF29-GGC-(tpBiocytin)-NH2, and hGRF29-GGC-(tpBiocytin)-NH2 displayed 8.6, 5.5, and 0.8 times, respectively, the potency of hGRF44. These in vivo potency values were not significantly different from the corresponding parent compounds (i.e., with or without the C-terminal spacer arm). In summary, biotinylated hGRF analogs have been developed that retain full immunoreactivity and potent bioactivity (in vitro and in vivo), thus permitting their use in GRF receptor isolation, ELISA, and histochemical procedures.  相似文献   
178.
The clinical effect of antibiotics in treatment of children at the age of 2 months to 5 years with acute pneumonia during a gnotobiological department in the wards of the 1st class purity and under the conditions of a routine pediatric hospital was estimated. The course of the antibiotic therapy amounted to 4.7 +/- 0.42 days in the gnotobiological department and 12.0 +/- 0.3 days in the routine hospital. After recovery the patients were discharged in 7.61 +/- 0.76 days from the gnotobiological department and in 15.2 +/- 1.11 days from the routine hospital.  相似文献   
179.
It is established that carboxypeptidase H activity increases as affected by various stress factors in the rat brain departments. The increase of the enzyme activity because of the emotional-pain stress is of continuous character. Possible role of carboxypeptidase H in the development of the stress response is discussed.  相似文献   
180.
An analysis of the results of the examination and treatment of 379 patients undergoing transthoracic interventions showed that the use of the target-aimed selective immunomodulation, short-term antibacterial prophylaxis, inhibitors of arachidonic acid metabolites, active elimination of the circulating immune complexes and medium-weight molecular peptides and adequate local analgesia after the interventions providing normalization of the laryngeal reflex and early activation of the patients permitted the incidence of the pulmonary complications to be decreased by 2.5 times, pleural complications by 1.7 times, suppuration of the postoperative wound by 1.8 times and the total expenses by 25.6 per cent.  相似文献   
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