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11.
In this study, antiserum raised against an insect myotropic peptide, leucokinin I (DPAFNSWGamide), was: used for mapping leucokinin-like immunoreactive (LK-LI) neurons in the gastropod mollusc, Helix pomatia. Immunocytochemistry performed on both whole-mounts and cryostat sections demonstrated LK-LI neurons in all ganglia of the central nervous system (CNS), except the visceral ganglion. Altogether about 700 immunolabelled neurons have been found, with nearly one-half (46%) in the cerebral ganglia. A large proportion of the LK-LI neurons have small cell bodies and are likely to be interneurons. The most prominent LK-LI cell group is represented by the entire neuron population of the mesocerebri, which is the major source of a thick fiber bundle system, encircling and innervating the whole CNS. One single LK-LI giant neuron was found, which is located in the left pedal ganglion and is termed GLPdLKC (giant left pedal leucokinin immunoreactive cell). This cell has not been identified previously. The ganglion neuropils are heavily innervated by varicose LK-LI fiber arborizations. Some integrative centers, such as the medullary neuropil of the procerebri, reveal an extreme density of LK-LI innervation. All major peripheral nerves contain a large number of LK-LI axons, and LK-LI innervation is found in the musculature of different peripheral organs (buccal mass, lip, tentacles, oviduct, intestine). Among the peripheral organs investigated, the intestine contains a rich varicose LK-LI network, composed of both intrinsic and extrinsic elements. Radioimmunoassay (RIA) demonstrates a very high content of LK-LI material in Helix ganglion extracts (about 50 pmol/CNS). This is the first report on the occurrence of a substance resembling the myotropic neuropeptide leucokinin I in a phylum outside arthropods. Based on our immunocytochemical observations, a role for leucokinin-like peptides in both central and peripheral regulatory processes in Helix is suggested. According to double-labelling experiments, only a small number of the LK-LI neurons are labelled with an antibody to the vertebrate tachykinin substance P.  相似文献   
12.
Twenty men, aged 50 to 75 years (mean, 67 years), suffering from benign prostatic hypertrophy received 160 mg of a lyposterolic extract of Serenoa repens, twice daily for 30 days. Before and at the end of treatment, plasma levels of testosterone, follicle-stimulating hormone, and luteinizing hormone were determined. No changes in plasma hormone levels occurred as a result of treatment. It is concluded that Serenoa extract, which is useful in the treatment of benign prostatic hypertrophy, does not act via systemic changes of hormone levels.  相似文献   
13.
After palliative procedure a 2 years old girl with congenital heart disease was corrected with aortic homograft. Truncus arteriosus is a rare congenital heart disease and this is the first successfully corrected case in our country. Using homograft in this age group improves the early and late result of this type of corrective surgery.  相似文献   
14.
Authors report on long term follow up of 12 patients operated with critical valvular aortic stenosis. They could perform control echocardiography in 11 patients 4-83 (mean 29) months after valvulotomy. The size and function of the left ventricle was found to be satisfactory, with elevated ejection fraction. The cause of the significant pressure gradient between the left ventricle and the aorta is discussed emphasizing the importance of echocardiography in determining the optimal time for valve replacement or homograft implantation.  相似文献   
15.
Single neuron activities in the lateral hypothalamic area (LHA) were recorded during bar press feeding task in the monkey. First registered neurons were sorted into 2 groups, glucose-sensitive (GS) and glucose-insensitive (GIS) neurons, depending on their glucose sensitivity. Then firing variations to feeding, electrophoretically applied catecholamines and opiate, and to odor and taste stimuli were investigated. GS neurons responded to dopamine, noradrenaline and morphine more often than GIS neurons. In feeding task GS neurons responded during bar press (BP) and reward (RW) periods with long-lasting inhibition of firing and at cue tone (CT) with transient inhibition, while GIS neurons responded during BP and RW periods mainly with excitation and at cue light (CL) with excitation. A majority of GS neurons responded to both odor and taste stimuli more often than GIS neurons. Data suggest that these two kinds of neurons in the LHA may be involved in different functional aspects of feeding: GS neurons, mainly in internal information processing and reward mechanism, and GIS neurons, in external information processing and motor aspects.  相似文献   
16.
Transglutaminase (TGase) activity was reduced in intact mitogen-stimulated human peripheral blood lymphocytes (PBL) when compared to intact resting PBL. Moreover, a treatment of the same quiescent immunocompetent cells with purified liver TGase and Ca2+ completely suppressed the mitogen-induced blast transformation. A decrease in TGase activity in neoplastically transformed seminal vesicle epithelial cells with respect to their normal parent counterpart was also observed. Our data support the notion of a possible implication of TGase in cell proliferation and transformation.  相似文献   
17.
The genetic basis for addiction to tobacco smoking--particularly that of the perception of olfactory stimuli that may be important in reinforcing smoking addiction--is largely unknown. A cluster of genes for olfactory receptors is in close proximity to the MHC region on chromosome 6. Polymorphisms of MHC class III genes (RCCX modules, TNFA promoter polymorphisms) were determined in 101 healthy subjects and 232 coronary artery disease (CAD) patients from Hungary with defined tobacco smoking habits. A highly significant association between ever smoking (past + current smokers) and a specific MHC haplotype was observed (odds ratios = 2.14-4.13; P-values = 0.012 to <0.001). This haplotype is characterized by the presence of C4A null alleles and a solitary short C4B gene linked to the TNF2 allele of the promoter for TNFA gene. This haplotype occurred more frequently in the ever smokers than in the never smokers [odds ratio: 4.97 (1.96-12.62); P = 0.001], and such associations were stronger in women (odds ratio = 13.6) than in men (odds ratio = 2.79). An independent study of complement C4 protein polymorphism and smoking habits in Icelandic subjects (n = 351) yielded similar and confirmative results. Considering the documented link between olfactory stimuli and smoking in females, and the presence of a cluster of odorant receptor genes close to the MHC class I region, our findings implicate a potential role of the MHC-linked olfactory receptor genes in the initiation of smoking.  相似文献   
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19.
Patterns of recruitment and attendance (1951-79) of general practitioners at seminars at the Tavistock Clinic are analysed. Latterly about 40 general practitioners have attended each week; a turnover of about 15 join or leave each year; about 60 per cent stay at least two years and 40 per cent stay over three years. Half come from outside London. The ratio of men and women reflects the prevailing ratio in the profession. Most join five to 10 years after qualifying and younger general practitioners tend to leave early. At least seven per cent of recent members have left general practice; but the proportion involved in training, course organizing and the Royal College of General Practitioners is far above the average for all general practitioners.  相似文献   
20.
To investigate the possible interactions between human and porcine interferons (IFNs) in vitro, human transformed (FL) and nontransformed (HEF) cells were treated with either HuIFN alpha and/or gamma and porcine alpha and/or gamma. In both cases the antiproliferative activity was measured to determine the effects of different combinations between human and porcine IFNs on cell proliferation. Combinations of human and porcine IFNs acted mostly antagonistically with exception of IFN combination Hu-alpha/Po-gamma which showed a synergic cooperativity in therms of antiproliferative activity on human transformed cells.  相似文献   
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