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In order to explore which amino acids or which blocks of amino acids in the 29 amino acid neuropeptide galanin are important for recognition of the endogenous ligand by galanin receptor subtypes present in the jejunum and in the hypothalamus, respectively, we have carried out L-Ala substitutions of individual amino acids or of blocks of amino acids in the rat galanin sequence and examined the binding of the obtained analogs to the rat hypothalamic and jejunal galanin receptor subtypes. This study reveals that the galanin sequence YLLGPH9–14 is essential for recognition of galanin by both the rat hypothalamic and jejunal galanin receptor subtypes. Substitution of the N-terminal amino acids, GWTL1–4, leads to total loss of affinity of galanin for both hypothalamic and jejunal galanin receptors. The α-helical C-terminal amino acid (25–29) part of galanin has no greater influence on the affinity of galanin to the hypothalamic galanin receptor subtype. L-Ala substitution of the C-terminal amino acids of galanin KHGLT25–29 shows, however, that this C-terminal motif is essential for the recognition by the jejunal galanin receptor subtype, whereas amino acids in the middle portion of galanin NSAG5–8 are of importance for binding to the hypothalamic but not to the jejunal receptor. [Ala5–8] Galanin thus has a more than 100-fold higher affinity to jejunal receptor than to the hypothalamic receptor, while [Ala25–29] galanin has a more than 100-fold higher affinity for the hypothalamic than for jejunal galanin receptor subtypes. pH dependence of the galanin binding to these receptor subtypes is also different. © Munksgaard 1997. 相似文献
3.
FMRFamide-like immunoreactive neurons of the nervus terminalis of teleosts innervate both retina and pineal organ 总被引:2,自引:0,他引:2
The tetrapeptide FMRFamide (Phe-Met-Arg-Phe-NH2) was first isolated from molluscan ganglia. Subsequently, it has become clear that vertebrate brains also contain endogenous FMRFamide-like substances. In teleosts, the neurons of the nervus terminalis contain an FMRFamide-like substance, and provide a direct innervation to the retina (Proc. Natl. Acad. Sci. U.S.A., 81 [1984] 940-944). Here we report the presence of FMRFamide-immunoreactive axonal bundles in the pineal organ of Coho salmon and three-spined sticklebacks. The largest numbers of axons were observed proximal to the brain, in the pineal stalk, while the distal part of the pineal organ contained only few axons. No FMRFamide-like-immunoreactive (IR) cell bodies were observed in the pineal organ. In adult fish it was not possible to determine the origin of these axons, due to the large numbers of FMRFamide-like IR axons in the teleost brain. However, by following the development of FMRFamide-like IR neurons in the embryonic and larval stickleback brain, it was possible to conclude that, at least in newly hatched fish, FMRFamide-like IR axons that originate in the nucleus nervus terminalis reach the pineal organ. Thus, it seems there is a direct connection between a specialized part of the chemosensory system and both the retina and the pineal organ in teleost fish. 相似文献
4.
This paper reports the health experience of compressed air workersduring construction of the Island Line Section of the Mass TransitRailway in Hong Kong. The requirements of CIRIA's Code of Practiceincluding specifications of the Blackpool Tables for decompressionprocedures and the employment of doctors to monitor the healthof exposed workers by regular examination were prescribed bylocal legislation. Over a 3 year period there were 394 716 man-decompressionsfrom pressures between 1 and 3-5 kg/cm2 with 2032 cases of acutedecompression sickness giving a bends rate of 0-52 per cent.The epidemiology followed the usual pattern of increase in bendsrate with increase in pressure and length of shift and withage. Most attacks occurred within a short period after decompressionand the majority of limb pains affected the leg. There werealso 10 cases of barotrauma and 22 cases of dysbaric osteonecrosisof which 7 resulted in some disability. The low incidence ofillness was an index of the effectiveness of the Code of Practiceas applied to a large scale compressed air work operation butthe toll of dysbarism, albeit small, underlines the problemthat there are as yet no decompression procedures which willprotect all men at all times and indicates the need for furtherresearch and work-site evaluation.
Requests for reprints should be addressed to: W. K. Lo, Occupational Health Division, Labour Department Headquarters, Harbour Building, 38 Pier Road, Central Hong Kong. 相似文献
5.
Pachydermodactyly refers to a rare form of digital fibromatosis involving the proximal portions of the fingers. There are only nine cases reported in the literature, ill idiopathic and occurring in young men. We report a 5-year-old Chinese boy with tuberous sclerosis who presented with localized pachydermodactyly since birth. This congenital form of pachydermodactyly may represent an additional cutaneous sign of tuberous sclerosis. 相似文献
6.
H-C. HSIA H-C. LIN F-Y. LEE Y-T. TSAI S-D. LEE H-C. MENG Y. CHAO S-S. WANG K-J. LO 《Journal of gastroenterology and hepatology》1993,8(1):15-20
Abstract Somatostatin has been used to effectively control acute variceal haemorrhage, with conjectured mechanisms on portal hypertension. We, therefore, evaluated the effects of somatostatin on hepatic and systemic haemodynamics in 15 patients with hepatitis B-related cirrhosis and portal hypertension. All patients received an intravenous, continuous infusion of somatostatin 250 μg/h, following a bolus injection of 250 μg. In systemic haemodynamics, the mean arterial pressure (MAP) increased ( P < 0.05), associated with a reflex bradycardia within 3 min following bolus injections, compared with basal values. The right atrial pressure, pulmonary capillary wedge pressure, inferior vena cava pressure, cardiac index, and systemic vascular resistance remained unaffected after drug infusion. In hepatic haemodynamics, the wedge hepatic vein pressure remained unchanged after drug administration. However, there was an increase in free hepatic vein pressure (FHVP; P < 0.05), and a trend toward a decrease in the hepatic vein pressure gradient (HVPG; P = 0.063), within 3 min after bolus injection. Furthermore, the hepatic blood flow decreased significantly at 10 and 30 min after somatostatin infusion ( P < 0.05). The effective sinusoidal perfusion assessed by indocyanine green infusion also decreased progressively at 10 min ( P = 0.057) and 30 min ( P < 0.05). We concluded that somatostatin, at the dose used in this study, caused a transient and bolus-related vasoconstrictive effect, resulting in increases in MAP and FHVP, a decrease in heart rate, and a trend toward lower HVPG. In addition, somatostatin reduced the hepatic blood flow and effective sinusoidal perfusion which may be hazardous to cirrhotic patients during variceal haemorrhage. 相似文献
7.
麝香保心丸治疗冠心病心绞痛临床疗效观察 总被引:5,自引:2,他引:5
目的 :观测麝香保心丸治疗冠心病心绞痛的疗效。方法 :将 2 0 0例冠心病心绞痛的患者随机分析治疗组 12 0例 ,对照组 80例 ,治疗组口服麝香保心丸 ,每次 2片 ,每日 3次 ,对照组口服单硝酸异酯脂 ,每次 2 0mg ,每日 2次。 结果 :麝香保心丸可显著改善冠心病心绞痛临床症状 ,显著改善心电图 ,缺血总面积。总的症状疗效 :治疗组为 83% ,对照组为6 1% ,(P <0 .0 5 ) ,心电图疗效 :治疗组为 74 % ,对照组为 4 6 % (P <0 .0 5 )。结论 :麝香保心丸治疗冠心病心绞痛优于单硝酸异山梨酯。 相似文献
8.
为探讨运动对青少年长骨发育的机理,本研究以大鼠作为实验模型,使生长期大鼠进行不同强度的跑台运动,同时结合悬吊和负重模型,采用体视学全视野无偏采样方法对不同强度运动和不同形式机械负荷的生长期大鼠骨量、骨结构、骨代谢等形态参数进行测试分析,取得运动与负荷对大鼠长骨发育影响的系列结果,为儿童少年生长发育状况的评价、运动和其它干预手段的选择以及运动处方的制订等提供部分依据。 相似文献
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10.
Nilsen TO Ebbesson LO Kiilerich P Björnsson BT Madsen SS McCormick SD Stefansson SO 《General and comparative endocrinology》2008,155(3):762-772
The present study compares developmental changes in plasma levels of growth hormone (GH), insulin-like growth factor I (IGF-I) and cortisol, and mRNA levels of their receptors and the prolactin receptor (PRLR) in the gill of anadromous and landlocked Atlantic salmon during the spring parr-smolt transformation (smoltification) period and following four days and one month seawater (SW) acclimation. Plasma GH and gill GH receptor (GHR) mRNA levels increased continuously during the spring smoltification period in the anadromous, but not in landlocked salmon. There were no differences in plasma IGF-I levels between strains, or any increase during smoltification. Gill IGF-I and IGF-I receptor (IGF-IR) mRNA levels increased in anadromous salmon during smoltification, with no changes observed in landlocked fish. Gill PRLR mRNA levels remained stable in both strains during spring. Plasma cortisol levels in anadromous salmon increased 5-fold in May and June, but not in landlocked salmon. Gill glucocorticoid receptor (GR) mRNA levels were elevated in both strains at the time of peak smoltification in anadromous salmon, while mineralocorticoid receptor (MR) mRNA levels remained stable. Only anadromous salmon showed an increase of gill 11beta-hydroxysteroid dehydrogenase type-2 (11beta-HSD2) mRNA levels in May. GH and gill GHR mRNA levels increased in both strains following four days of SW exposure in mid-May, whereas only the anadromous salmon displayed elevated plasma GH and GHR mRNA after one month in SW. Plasma IGF-I increased after four days in SW in both strains, decreasing in both strains after one month in SW. Gill IGF-I mRNA levels were only increased in landlocked salmon after 4days in SW. Gill IGF-IR mRNA levels in SW did not differ from FW levels in either strain. Gill PRLR mRNA did not change after four days of SW exposure, and decreased in both strains after one month in SW. Plasma cortisol levels did not change following SW exposure in either strain. Gill GR, 11beta-HSD2 and MR mRNA levels increased after four days in SW in both strains, whereas only the anadromous strain maintained elevated gill GR and 11beta-HSD2 mRNA levels after one month in SW. The results indicate that hormones and receptors of the GH and cortisol axes are present at significantly lower levels during spring development and SW acclimation in landlocked relative to anadromous salmon. These findings suggest that attenuation of GH and cortisol axes may, at least partially, result in reduced preparatory upregulation of key gill ion-secretory proteins, possibly a result of reduced selection pressure for marine adaptations in landlocked salmon. 相似文献