Spatio-temporal changes in the metabolic processes in the blood-tissue system in the terminal states of the organism

The role of synergism in diffusion of oxygen from erythrocyte into interstitial liquid and water filtration through the capillary wall was studied on the model using the following parameters: hydrostatic pressure on arterial and venous ends of the capillary (Pa and Pb), oncotic blood and tissue pressure (Pob and Pot), pore radius in the capillary (r), the number of pores in the capillary (n) per m2, amount of the liquid released from the capillary (q(x)), gas diffusion coefficient (D), time of erythrocyte movement in the capillary (T), speed of oxygen consumption (V), maximal distance with adequate V (Xmax), characteristic time of diffusion (Topt). It is shown that diffuse and convective components of the metabolic process have their own contribution and in changed conditions they redistribute. In increased number and diameter of hydravlic pores the greatest role in tissue saturation with oxygen belongs to convective metabolism, but in this situation tissues contain areas lacking oxygen.     

Changes in the edentate mandible in the elderly

Resorption of alveolar bone is the best recognized feature of mandibular aging in the edentate subject. The other consequences of the loss of teeth in the elderly are less well known. An anthropometric study of the mandible by antero-posterior and lateral radiographs of subjects older than 70 years both dentate and edentate but without any maxillo-mandibular dysmorphosis has been done to demonstrate the differences, which exist between the dentate and edentate mandible. The edentate mandibles showed a diminution in the height of the symphysis and increase in the height of the mandibular incisure. A diminution in the height of the body and an increase in the gonial angle in the significant manner. No significant difference was seen for the height of the ramus and the length of the mandible, the minimum width of the ramus and the bigonial width. The diminution in the height of the mandibular symphysis and of the body is explained by the resorption of the alveoli part of the mandible. The increase in the mandibular angle and the diminution in the height of the mandibular incisure may be explained by disequilibrium between the elevator and depressor muscles of the mandible, as a function of the elevator muscles or by the absence of the molar buttress.     

On the role of the lymphoid follicle-associated areas in the organization of the bursal follicle in the cloacal bursa in birds

The present paper contains data on the morphological modifications present in chicks which, after treatment with testosterone lasting 10 days (from the seventh to the seventeenth days after hatching), were killed on the 30th, 35th, 40th, 50th and 70th day of life; this interval of time might theoretically have allowed a gradual re-establishment of the bursal architecture. Examination of the bursae of Fabricus of the animals treated showed greatly varying pictures. The 2 main types of behaviour were the following: the histological pattern of certain bursae had been completely restored to normal. Others did not act in the same way but wide areas of their plicae proved to be devoid of lymphoid tissue and well-formed lymphoid follicles were observed only in certain places. These 2 kinds of behaviour, and particularly what we observed in the second case, might suggest that, since the lymphoid follicle-associated epithelial cells are the last to disappear after treatment with testosterone propionate and the follicles are restored only where these cells remain, the lymphoid follicle-associated epithelial cells may be considered to be responsible for the re-establishment of the bursal follicle.     

Changes in the adrenals in the sudden death syndrome in infants

Adrenal glands of 52 children dying from a syndrome of sudden death (SSD) and 14 children of the same age dying from acute viral respiratory infections (AVRI) with a long terminal period were studied. The following adrenal changes typical for the SSD were observed: low weight, decrease of the size of the definitive cortex and its zones, the appearance of numerous adenomatous growths in the definitive cortex and so-called giant cells in the fetal cortex, low secretory activity. The appearance of adenomas and giant cells in the presence of organ hypoplasia is a compensatory-hyperplastic adrenal response which attests to a long glucocorticoid deficiency in the SSD. It is suggested that the deficiency of these hormones leads to the metabolic disturbances in various organs, including brain, resulting in the narrowing of the range of homeostatic host responses; this may become the cause of sudden death when the clinical and morphological manifestations of AVRI are insignificant.     

神经调节蛋白1在神经发育中的研究进展

神经调节蛋白1(neuregulin 1,NRG1)是一类含有表皮生长因子样结构域的营养因子.NRG1与其受体ErbB构成的NRG1-ErbB信号通路在神经发育中发挥着重要作用,与精神分裂症等神经发育异常所导致的疾病密切相关.更好的理解NRG1-ErbB在神经发育中的机制有助于发展更有效的针对神经发育疾病的治疗措施,现就近年来NRG1在神经发育中的研究进展作一综述.     

Stimulus specificity in the habituation of the startle response in the rat

A series of experiments evaluated whether the habituation of the startle response of the rat to tactile and auditory cues is stimulus specific. Experiment 1 showed stimulus specificity of a short-term habituation effect, whereby the startle to the second of a pair of stimuli was significantly less when the initial stimulus involved the same rather than the different modality. Experiments 2 and 3 focused on the more persistent decrement in startle that is a result of repeated stimulation, and demonstrated that such long-term habituation to the tactile and auditory stimuli contained a stimulus specific component in addition to a generalized component. The generalized habituation observed between the tactile and auditory stimuli in the three experiments may be due to an auditory accompaniment of the tactile stimulus employed. Discussion emphasized the utility of investigating habituation in a preparation with robust specificity.     

Challenges in the Management of Asthma in the Elderly

Recent literature has emphasized the clinical and socio-epidemiological significance of asthma in the elderly. However, why the disease burden remains high in this group is unclear. Elderly subjects usually have multiple chronic illnesses, and the role played by comorbidities in the context of asthma has been underappreciated. This review aims to summarize the literature associations between comorbidities and asthma in elderly patients. In addition, we discuss patient management issues.     

Changes in the testes following vasectomy in the rat

Six months and more after unilateral vasectomy in the rat, ipsilateral (same side) and bilateral testicular atrophy are common; this paper investigates their etiology. Ipsilateral atrophy is associated with the presence of a sperm granuloma in the head of the corresponding epididymis and appears to be pressure-mediated. That sperm granulomas at the epididymal head fail to relieve intraluminal pressure in the epididymal duct of the rat was supported by a study of the effects of ligation of that region. No histological evidence was found to indicate that bilateral atrophy was the result of an immune response. A radiological study does not support the idea that compression or displacement of testicular blood vessels by sperm granulomas is responsible for bilateral atrophy. © 1996 Wiley-Liss, Inc.     

Life in the Future Versus Life in the Present

Roemer and Orsillo have provided an integrative perspective for developing more effective therapies for generalized anxiety disorder, based on existing knowledge about the disorder, cognitive behavioral approaches to its treatment, and conceptualizations and treatment methods from the acceptance/mindfulness tradition. The present commentary expands upon the notion of the adaptive value of focused attention on present-moment experience and cognitive perspectives that can facilitate that process.     

Child care in the new towns in the UK

New towns with large populations of children present ideal opportunities to study and implement extended primary care services for children. It appears that workload in most new towns is higher than in established communities. Often, the demanding nature of new town practice seems to have precluded innovations in primary care services for children. This report, which is general-practice orientated, can only indicate some aspects of child care in new towns which require further scrutiny. General practitioners are strongly divided in their views as to how they can act most effectively in child health, but there is no doubt that there is a chance in our new towns to nurture the idea of expanding the general practitioner's role in child care.