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Summary In the pars tuberalis of the hypophysis of Rana temporaria, which shows the ultrastructural characteristics of a polypeptide hormone secreting endocrine gland, seasonal changes of the ultrastructure are described. In accordance with the literature, these seasonal changes of ultrastructure are interpreted as the morphological expression of seasonal changes of endocrine activity of the pars tuberalis. 相似文献
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肺癌在中国恶性肿瘤的发病率位居第一,随着低剂量薄层CT在肺癌筛查中的广泛应用,临床发现更多表现为非完全实性结节的肺腺癌,目前众多研究使CT影像学特征和肺腺癌病理的关系得到更进一步的认知,虽然CT能对部分非完全实性结节做出定性和定位诊断,但仍有部分非完全实性结节诊断困难,PET-CT结合了病灶的代谢信息和精确的定位信息,从而提高对肺部结节诊断的敏感性、特异性、准确性,综合多个文献PET-CT在非完全实性结节中的诊断分期价值较CT无明显提升,却在评估预后和制定合适手术方案上可以起到一定的作用,本文就PET-CT在SSN中的应用价值进行阐述。 相似文献
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The brain of the lizard, Ctenosauria pectinata, was studied light microscopically using an immunocytochemical staining method that is specific for neurohypophysial hormones and somatostatin. It was shown that the telencephalon and particularly the diencephalon contain somatostatin-producing perikarya, while somatostatinergic fibers occur in the entire brain. Similar to the situation in other vertebrates, somatostatin neurons in Ctenosauria pectinata form a population distinct from the neurohypophysial hormone-producing neurons. The small-sized somatostatin neurons were found in the cortex and the diencephalon: (1) ventral from, and partially overlapping with, the classical neurosecretory paraventricular nucleus; and (2) in the region of the infundibular (tuberal) nucleus. Somatostatin fibers were found among the classical neurosecretory fibers of the supraoptico-paraventricular system (tract, median eminence, neural lobe), near to and within the epiphysis, in the septum, in the vicinity of the tectum opticum and the cerebellum, and in the tegmentum. 相似文献
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B. De Corte D. Dries W. Verstraete P. Stevens L. Goossens P. De Vos J. De Ley 《Biotechnology letters》1989,11(8):583-588
Summary The metabolite pattern of batch cultures ofLactobacillus
casei LMG 6400,Clostridium
butyricum LMG 1213t1 andEscherichia
coli LMG 2093 was effected only for the latter organism when the H2 partial pressure was below 1 atmosphere: high hydrogen partial pressures increased the formate formation, low pressures gave rise to increased acetate production and higher cell yields. 相似文献
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New enrichment method for isolation of pathogenic Yersinia enterocolitica serogroup O:3 from pork 总被引:3,自引:0,他引:3
G Wauters V Goossens M Janssens J Vandepitte 《Applied and environmental microbiology》1988,54(4):851-854
A new enrichment medium for the recovery of pathogenic Yersinia enterocolitica serogroup O:3 from naturally infected meat products based on three selective agents, Irgasan, ticarcillin, and potassium chlorate (ITC), was compared with several other one- or two-step enrichments. Y. enterocolitica serogroup O:3 was recovered from 96.5% of 29 pork tongues, 24% of 50 ground pork samples, 16% of 25 masseter muscle samples, and 61% of tonsils. ITC was by far the most sensitive method for the recovery of Y. enterocolitica O:3, especially from ground meat and masseter muscles, while cold and two-step enrichments yielded better results for nonpathogenic strains. Plating of ITC enrichments onto SS-deoxycholate-calcium agar gave overall better results than plating onto cefsulodin-Irgasan-novobiocin agar for serogroup O:3. 相似文献
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烟青虫感染核型多角体病毒后围食膜的病变 总被引:4,自引:1,他引:3
昆虫的围食膜是衬在昆虫中肠内一种网状的结构,它可充作虫体抵御外来病原侵染的一道屏障。关于鳞翅目昆虫幼虫感染了昆虫病毒后围食膜的病变问题,国内外鲜有报道。尤锡镇和康慧娟(1985)曾以实验证明家蚕围食膜对核型多角体病毒有灭活作用,而且认为核型多角体病毒不能侵染和破坏围食膜。Derksen和Granados(1988)则证明染病幼虫的围食膜因不同杆状病毒(包括两种核型多角体病 相似文献
10.
Determination of the spectrum of beta-thalassemia genes in Spain by use of dot-blot analysis of amplified beta-globin DNA. 总被引:3,自引:1,他引:2 下载免费PDF全文
S Amselem V Nunes M Vidaud X Estivill C Wong L d''''Auriol D Vidaud F Galibert M Baiget M Goossens 《American journal of human genetics》1988,43(1):95-100
We have delineated the molecular lesions causing beta-thalassemia in Spain, a country that has witnessed the passage of different Mediterranean populations over the centuries, in order to evaluate the extent of heterogeneity of these mutations and to make possible simplified prenatal diagnosis of the disorder in that country. The use of the polymerase chain-reaction (PCR) technique to preferentially amplify beta-globin DNA sequences that contain the most frequent beta-thalassemia mutations in Mediterraneans enabled us to rapidly analyze 58 beta-thalassemia alleles in a dot-blot format either by hybridization with allele-specific radiolabeled oligonucleotide probes or by direct sequence analysis of the amplification product. The Spanish population carries seven different beta-thalassemia mutations; the nonsense codon 39 is predominant (64%), whereas the IVS1 position 110 mutation, the most common cause of beta-thalassemia in the eastern part of the Mediterranean basin, is underrepresented (8.5%). The IVS1 mutation at position 6 accounts for 15% of the defects and leads to a more severe form of beta+-thalassemia than originally described in most of the patients we studied. In this study, we demonstrate further the usefulness of the dot-blot hybridization of PCR-amplified genomic DNA in both rapid population surveys and prenatal diagnosis of beta-thalassemia. 相似文献