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61.
本文回顾我院20年来所收治的100例颈椎损伤合并截瘫伤员,试图对诊断和处理方法上若干主要问题提出探讨。 相似文献
62.
Abstract – Dental injuries are common following facial trauma. This article presents a rare injury: the dislocation of a third molar into the maxillary sinus after complex mandibular and maxillary tuberosity fractures. The possible mechanism and clinical treatment are discussed. 相似文献
63.
64.
L-Ascorbic acid (Vitamin C) produced a marked reduction in the blood glucose concentration following intravenous injection (20-100 mg kg-1) to anaesthetized rats. This hypoglycaemic effect was accompanied by an increase in plasma insulin concentration. D-ascorbic acid produced a similar hypoglycaemic effect. 相似文献
65.
Solid-phase synthesis of 16 potent (selective and nonselective) in vivo antagonists of oxytocin 总被引:7,自引:0,他引:7
M Manning M Kruszynski K Bankowski A Olma B Lammek L L Cheng W A Klis J Seto J Haldar W H Sawyer 《Journal of medicinal chemistry》1989,32(2):382-391
We describe the synthesis and some pharmacological properties of 16 new in vivo antagonists of oxytocin. These are based on modifications of three peptides: A, B, and C. A is our previously reported potent and selective antagonist of the vasopressor (V1 receptor) responses to arginine-vasopressin (AVP)/weak oxytocin antagonist, [1-(beta-mercapto-beta,beta-pentamethylenepropionic acid), 2-O-methyltyrosine]arginine-vasopressin (d(CH2)5[Tyr(Me)2]AVP. B reported here, the Ile3 analogue of A, is d(CH2)5[Tyr(Me)2]AVT (5 below) and C is our previously reported potent nonselective oxytocin antagonist/AVP V1 antagonist, [1-(beta-mercapto-beta,beta-pentamethylenepropionic acid),2-O- methyltyrosine,8-ornithine]vasotocin (d(CH2)5[Tyr(Me)2]OVT). The following substitutions and deletions, alone or in combination, were employed in A, B, and C: 1-deaminopenicillamine (dP); D-Tyr(Alk)2 (where Alk = Me or Et), D-Phe2; Val4, Thr4; delta 3-Pro7; Lys8, Cit8; desGly9, desGly-NH2(9), Ala-NH2(9); Leu-NH2(9); Arg-NH2(9). The 16 new analogues are (1) d(CH2)5[D-Tyr(Me)2]AVP, (2) d(CH2)5[D-Tyr(Me)2, Val4,delta 3-Pro7]AVP, (3) d(CH2)5[D-Tyr-(Et)2, Val4,Lys8]VP, (4) d(CH2)5[D-Tyr(Et)2,Val4,Cit8]VP, (5) d(CH2)5[Tyr(Me)2]AVT, (6) d(CH2)5[Tyr(Me)2,Lys8]VT, (7) dP[Tyr(Me)2]AVT, (8) dP[Tyr(Me)2,Val4]AVT, (9) d(CH2)5[D-Tyr(Me)2, Val4]AVT, (10) d(CH2)5[D-Phe2,Val4]AVT, (11) d(CH2)5[Tyr(Me)2,Thr4]OVT, (12) d(CH2)5[Tyr(Me)2,Thr4,Ala-NH2(9)]OVT, (13) d(CH2)5[Tyr(Me)2,Thr4,Leu-NH2(9)]OVT, (14) d(CH2)5[Tyr(Me)2,Thr4,Arg-NH2(9)]OVT, (15) desGly-NH2(9),d(CH2)5[Tyr(Me)2,Thr4]OVT, (16) desGly9,d(CH2)5[Tyr(Me)2,Thr4]OVT. 1-4 are analogues of A, 5-10 are analogues of B, and 11-16 are analogues of C. Their protected precursors were synthesized either entirely by the solid-phase method or by a combination of solid-phase and solution methods (1 + 8 or 8 + 1 couplings). All analogues were tested in rats for agonistic and antagonistic activities in oxytocic (in vitro, without and with Mg2+, and in vivo) assays as well as by antidiuretic and vasopressor assays. All analogues exhibit potent oxytocic antagonism in vitro and in vivo. With an in vitro pA2 (in the absence of Mg2+) = 9.12 +/- 0.09, dP[Tyr(Me)2]AVT is (7) one of the most potent in vitro oxytocin antagonists reported to date. Fifteen of these analogues (all but 6) appear as potent or more potent in vivo oxytocin antagonists than C (pA2 = 7.37 +/- 0.17). Analogues 1-9 and 14 are potent AVP V1 antagonists. Their anti-V1 pA2 values range from 7.92 to 8.45. They are thus nonselective oxytocin antagonists.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
66.
Delivery of anticancer drugs 总被引:1,自引:0,他引:1
R K Zee-Cheng C C Cheng 《Methods and findings in experimental and clinical pharmacology》1989,11(7-8):439-529
67.
成意伟 《中华实用中西医杂志》2005,18(20):1330-1332
糖尿病肾病(DN)是糖尿病全身性微血管合并症之一,即糖尿病性肾小球硬化证,是糖尿病特异的肾损害,是糖尿病致死的重要原因之一。有效地治疗DN、延缓其肾功能减退的进程,是临床亟待解决的难题。积极寻求有效方药,提高疗效,临床医师做了大量研究,现综述如下。 相似文献
68.
Pro-opiomelanocortin messenger ribonucleic acid and posttranslational processing of beta endorphin in spleen macrophages. 总被引:12,自引:6,他引:6 下载免费PDF全文
S J Lolait J A Clements A J Markwick C Cheng M McNally A I Smith J W Funder 《The Journal of clinical investigation》1986,77(6):1776-1779
We have previously demonstrated low levels of immunoreactive (ir)-beta-endorphin (beta-EP) and ir-ACTH in a subpopulation of mouse spleen macrophages, which is consistent with an involvement of opioid peptides in modulation of immune responses. Gel chromatography studies suggested the presence of an approximately 3.5,000-molecular weight (mol wt) species, putatively beta-EP, an approximately 11.5,000-mol-wt species, putatively beta-lipotropin, and a higher molecular weight species (putative beta-EP precursor, pro-opiomelanocortin (POMC). In this study we have extended our original findings by demonstrating the presence of messenger RNA for POMC by the use of a complementary DNA probe and Northern blot analysis of extracts of mouse and rat spleen. In addition, using high performance liquid chromatography (HPLC), we have shown that the major endorphin species in mouse spleen macrophages is beta-EP1-31, and that there are smaller amounts of each of the acetylated forms, N-acetyl-beta-EP1-16 (alpha-endorphin), N-acetyl-beta-EP1-17 (gamma-endorphin), N-acetyl-beta-EP1-27, and N-acetyl-beta-EP1-31. We interpret these studies as showing that (a) the spleen is an organ of POMC synthesis and that (b) the predominant COOH-terminal product of macrophage POMC is the opiate-receptor active species beta-EP1-31. 相似文献
69.
采用离心法收集羽化后不同天数的雌雄虫血淋巴,用意大利CABLOERBA3A3o型氨基酸自动分析仪测定,共检出10种氨基酸和1个氨残基,其氨基酸总量及每种氨基酸的含量与成虫性别、不同发育期有密切的关系。 相似文献
70.
Tissue samples from 30 patients with adenoid cystic carcinoma and 20 with adenocarcinoma of salivary gland origin were studied by immunohistochemical staining with specific antibodies to the four macromolecules that are present in normal basement membranes: type IV collagen, laminin, heparan sulfate proteoglycan, and entactin. In the adenoid cystic carcinoma samples, the four proteins were localized in different types of extracellular matrices in the tumor, namely pseudocystic spaces, hyaline stroma, and around tumor cell nests. The staining intensity was enhanced by pretreatment with hyaluronidase. The tumor cells of adenoid cystic carcinoma showed a tendency to proliferate with individual cells in contact with the basement membrane and to infiltrate through basement membrane-rich tissues, such as peripheral nerves, blood vessels, and skeletal muscles. In contrast, only circumferential staining of tumor cell nests was obtained in adenocarcinoma samples. The results suggest that adenoid cystic carcinoma is a tumor with affinity for basement membranes, and this basic feature is reflected in its histology and presumably in its biologic behavior. Immunostaining with antibodies to basement membrane proteins appears to be useful for differential diagnosis of some types of these two carcinomas. 相似文献