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81.
82.
SM Dyer IS de la Lande DB Frewin & RJ Head 《Clinical and experimental pharmacology & physiology》1998,25(3-4):246-251
1. 5-Hydroxytryptamine (5-HT) exerts both contractile and relaxant effects in the marmoset isolated aorta, actions that are unaffected by the 5-HT2 antagonist ketanserin. The aim of the present study was to define the receptors mediating the contractile activity of 5-HT in the marmoset aorta.
2. Contractile responses were elicited in aortic rings that were either: (i) precontracted submaximally with the thromboxane A2 agonist U44069 in order to amplify the responses; or (ii) exposed to N ω -nitro- L -arginine (100 μmol/L) plus LY 53857 (0.1 μmol/L; a 5-HT2 receptor antagonist shown previously to inhibit relaxation). The effect of 5-HT on adenosine 3',5'-cyclic monophosphate (cAMP) formation was also investigated.
3. The effects of agonists and antagonists comprised: (i) agonist potencies in the order 5-carboxamidotryptamine > 5-HT > sumatriptan > 8-hydroxy-2-(di- n -propylamino)tetralin; (ii) inhibition of contractile action of 5-HT by the 5-HT1D antagonist GR 127935; (iii) a contractile response to methysergide; (iv) a lack of effect of tropisetron, an antagonist of 5-HT3 and 5-HT4 receptors; and (v) inhibition of forskolin-stimulated cAMP formation by 5-HT (in the presence of LY 53857), indicative of negative coupling to adenylate cyclase.
4. The above effects fulfil the criteria for a 5-HT1 -like receptor. In view of the previous finding that this contractile response is insensitive to ketanserin, it is concluded that the contractile effects of 5-HT in the marmoset aorta are mediated exclusively by a 5-HT1 -like receptor. 相似文献
2. Contractile responses were elicited in aortic rings that were either: (i) precontracted submaximally with the thromboxane A
3. The effects of agonists and antagonists comprised: (i) agonist potencies in the order 5-carboxamidotryptamine > 5-HT > sumatriptan > 8-hydroxy-2-(di- n -propylamino)tetralin; (ii) inhibition of contractile action of 5-HT by the 5-HT
4. The above effects fulfil the criteria for a 5-HT
83.
84.
MM Harjai DC Agarwal P Dave SS Jog P Arora SM VSM 《Medical Journal Armed Forces India》2005,61(2):143-147
Background
The sudden increase in incidence and magnitude of mine blast injuries prompted us to highlight the problem and its management.Methods
The cases of mine blast injuries occurring during mining and demining in a particular geographical area were analysed. Total 27 cases of mine blast injuries occurred during mining or demining operations in a period of 13 months.Results
Various body regions were involved in the mine blast injuries but the main brunt was borne by feet and legs followed by multiple body regions due to splinters. 14 patients underwent below knee (BK) amputation while 4 patients required through knee (TK) amputations. The effect of blast was so severe that most of the cases required 2 to 5 times wound debridements. The initial aggressive debridement / open stump amputation saved the limb and life of all patients.Conclusion
A mine blast causes extensive injuries and psychological trauma. Management is needed urgently, surgery is difficult, and amputation is often inevitable. Maximum lives and limbs can be saved with aggressive debridement, repeated inspections and dressings under anaesthesia and definitive closure at optimum time.Key Words: Amputation, Antipersonnel mine, Crush syndrome, Debridements, Mine blast injury, Secondary missiles, Shrapenels 相似文献85.
86.
Minimally invasive techniques as the first line of management in vascular reconstruction are beginning to replace older surgical techniques. General and specific approaches in the endovascular reconstruction of branches off the aortic arch (innominate and subclavian arteries) and the visceral branches off the abdominal aorta (renal and mesenteric arteries) are described. The branches of the aortic arch and the visceral arteries are discussed together because of the similarity in the interventional techniques used for revascularization. Patient selection, endoluminal techniques, complications, and patient management will also be discussed. 相似文献
87.
88.
Over 200 measurements of the resting rate of oxygen consumption using an open-circuit method were made on 15 small babies nursed in their usual clinical setting during the first month of life. There were striking and persistent variations between babies that could not be explained by postnatal age, relationship to feed, sleep, or time of day. It was not possible from clinical examination to predict which babies had the higher or lower metabolic rates, except that babies who were light-for-dates generally had higher values. Because of these variations the appropriate thermal temperature for small babies cannot be predicted from average values adjusted for body weight and postnatal age alone. 相似文献
89.
N Yang SM Liu LF Zheng T Ji Y Li XL Mi H Xue W Ren JD Xu XH Zhang LS Li Y Zhang JX Zhu 《British journal of pharmacology》2010,159(8):1623-1625
Background and purpose:
5-Hydroxytryptamine (5-HT) is a key regulator of the gastrointestinal system and we have shown that submucosal neuronal 5-HT3 receptors exerted a novel inhibitory effect on colonic ion transport. The aim of the present study was to investigate the precise mechanism(s) underlying this inhibitory effect.Experimental approach:
Mucosa/submucosa or mucosa-only preparations from rat distal colon were mounted in Ussing chambers for measurement of short-circuit current (Isc) as an indicator of ion secretion. Somatostatin release was determined with radioimmunoassay. Intracellular cAMP content was measured with enzyme-linked immunoadsorbent assay (elisa). Immunohistochemical techniques were used to study the expression of 5-HT3 receptors, somatostatin and somatostatin receptors in colonic tissue.Key results:
In rat distal colonic mucosa/submucosa preparations, pretreatment with 5-HT3 receptor antagonists enhanced 5-HT-induced increases in Isc. However, in mucosa-only preparations without retained neural elements, pretreatment with 5-HT3 receptor antagonists inhibited 5-HT-induced ΔIsc. Pretreatment with a somatostatin-2 (sst2) receptor antagonist in mucosa/submucosa preparations augmented 5-HT-induced ΔIsc. Combination of sst2 and 5-HT3 receptor antagonists did not cause further enhancement of 5-HT-induced ΔIsc. Moreover, both sst2 and 5-HT3 receptor antagonists enhanced 5-HT-induced increase in intracellular cAMP concentration in the mucosa/submucosa preparations. 5-HT released somatostatin from rat colonic mucosa/submucosa preparations, an effect prevented by pretreatment with 5-HT3 receptor antagonists. Immunohistochemical staining demonstrated the presence of 5-HT3 receptors on submucosal somatostatin neurons and of sst2 receptors on colonic mucosa.Conclusion and implications:
Activation of neuronal 5-HT3 receptors in the submucosal plexus of rat colon suppressed 5-HT-induced ion secretion by releasing somatostatin from submucosal neurons. 相似文献90.
JKS Parihar SM DP Vats SM VSM RP Gupta TR Bera R Phooken A Singh 《Medical Journal Armed Forces India》2007,63(1):19-22