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51.
Common origin of the Val30Met mutation responsible for the amyloidogenic transthyretin type of familial amyloidotic polyneuropathy 总被引:3,自引:0,他引:3
52.
Kaoru Fujiyarna Masao Kishikawa Hideharu Fuji Tadayoshi Moriyarna Kengo Fuchigami Masachika Iseki Kiyoto Shinkai 《Pathology international》1990,40(5):376-382
We report a 6-year-old girl with anaplastic ependymoma probably originating in the region of the conus medullaris and probably spreading retrogradely to the region of the interventricular foramen (Monro) through the cere-brospinal fluid (CSF). Since ependymoma of the spinal cord rarely occurs in children, and retrograde spreading is extremely rare, the histological features and mechanism of metastasis of the tumor are discussed. 相似文献
53.
T. Kubo M. Kihara H. Hata Y. Misu 《Naunyn-Schmiedeberg's archives of pharmacology》1987,335(3):274-277
Summary The cardiovascular effects of selective alpha1 and alpha2 agonists and antagonists injected into the nucleus tractus solitarii (NTS) were studied in urethane-anesthetized rats. Methoxamine (0.3–3 g) injected bilaterally into the NTS caused a dose-dependent increase in blood pressure and heart rate. Phenylephrine (6 g) and an imidazolidine derivative St 587 (3 g) similarly injected also produced an increase in blood pressure, whereas a-methylnoradrenaline and an azepine derivative B-HT 920 (1 and 3 g) caused a decrease in blood pressure and heart rate. The pressor response to methoxamine (1 g) was markedly inhibited by prazosin (0.3 pg) injected into the same sites or hexamethionum (25 mg/kg, i. v.). Prazosin (0.3 g) alone injected bilaterally into the NTS did not affect the blood pressure, while yohimbine (0.1 g) similarly injected increased the pressure. These results suggest that in the rat NTS there exist alpha1 adrenoceptors responsible for an increase in arterial pressure. The NTS alpha2 adrenoceptors seem to be involved in the tonic regulation of arterial pressure.
Send offprint requests to T. Kubo at the above address 相似文献
54.
Conclusion Nous pensons que nous devons clairement préciser non seulement la distribution des branches de la v. porte, mais aussi celle des v. hépatiques drainant une tumeur afin de faciliter au mieux la résection hépatique à réaliser tout en conservant un maximum de parenchyme fonctionnel. Lorsqu'un segment doit être réséqué, il est nécessaire d'étudier la morphologie des veines et de leurs branches par phlébographie hépatique préopératoire afin de bien préciser les limites de la résection en fonction du siège de la tumeur. 相似文献
55.
Complement factor D (FD) is a serine protease that plays an essential role in the activation of the alternative pathway (AP) by cleaving complement factor B (FB) and generating the C3 convertases C3(H2O)Bb and C3bBb. FD is produced mainly from adipose tissue and circulates in an activated form. On the contrary, the other serine proteases of the complement system are mainly synthesized in the liver. The activation mechanism of FD has long been unknown. Recently, a serendipitous discovery in the mechanism of FD activation has been provided by a generation of Masp1 gene knockout mice lacking both the serine protease MASP-1 and its alternative splicing variant MASP-3, designated MASP-1/3-deficient mice. Sera from the MASP-1/3-deficient mice had little-to-no lectin pathway (LP) and AP activity with circulating zymogen or proenzyme FD (pro-FD). Sera from patients with 3MC syndrome carrying mutations in the MASP1 gene also had circulating pro-FD, suggesting that MASP-1 and/or MASP-3 are involved in activation of FD. Here, we summarize the current knowledge of the mechanism of FD activation that was finally elucidated using the sera of mice monospecifically deficient for MASP-1 or MASP-3. Sera of the MASP-1-deficient mice lacked LP activity, but those of the MASP-3-deficient mice lacked AP activity with pro-FD. This review illustrates the pivotal role of MASP-3 in the physiological activation of the AP via activation of FD. 相似文献
56.
Vascular anatomy of the pancreaticoduodenal region: A review 总被引:4,自引:0,他引:4
G. Murakami K. Hirata T. Takamuro M. Mukaiya F. Hata S. Kitagawa 《Journal of Hepato-Biliary-Pancreatic Surgery》1999,6(1):55-68
Vascular anatomy of the pancreaticoduodenal region has been the subject of numerous studies. However, several essential areas
of confusion remain in interpretation of the vascular configuration. We note and discuss three key points in relation to this
confusion: (1) a missing vascular arcade, (2) a rearrangement of the arcade by collateral and/or transverse vessels, and (3)
a solitary vessel without an accompanying comites vein or artery. In addition, we consider that different interpretations
as well as varying reported incidences depend on different "thresholds" when observations are made. Consideration of new aspects
of vascular anatomy of the pancreaticoduodenal region is required for further improvement of surgical procedures. In terms
of the selection of lymph node resection procedure, we discuss mainly the inferior arterial origin. Special attention should
be paid to the ligation of inferior arteries because of the high incidence of the common trunk formation of the upper jejunal
and inferior pancreaticoduodenal arteries. With regard to duodenum-preserving pancreatic head resection for benign tumors,
our observations are introduced in view of either arterial or venous configuration. First, a communicating artery between
the anterior and posterior arterial arcades is noted because of its possible critical role in blood supply to the papilla
of Vater. Second, a venous drainage route from the duodenum to the retroperitoneal space in "normal" specimens is described.
Received for publication on June 17, 1998; accepted on July 27, 1998 相似文献
57.
Sezai A Shiono M Orime Y Nakata K Hata M Iida M Kashiwazaki S Kinoshita J Nemoto M Koujima T Furuichi M Eda K Hirose H Yoshino T Saitoh A Taniguchi Y Sezai Y 《Artificial organs》1999,23(3):280-285
We examined a major organ function during 3 h biventricular assisted circulation after acute myocardial infarction model in the pig. In left ventricular circulation, the outflow cannula was placed in the ascending aorta and an inflow cannula through the mitral valve in the left ventricle. A pump (pulsatile group, Zeon Medical, Inc., Tokyo, Japan and nonpulsatile group, Nikkiso HPM-15, Nikkiso, Inc., Tokyo, Japan) was connected to each cannula. In right ventricular circulation, the outflow cannula was placed in the pulmonary artery and an inflow cannula in the right ventricle. The right ventricular circulation was supported by a nonpulsatile pump (Nikkiso HPM-15). The items measured were the regional blood flows of the cortex and medulla in the kidney, white matter and gray mater in brain, and liver; renal arterial flow; carotid arterial flow; portal vein flow; common hepatic arterial flow; arterial ketone body ratio (AKBR); and lactate/pyrubic acid (L/P). In the pulsatile group, the renal cortical blood flow increased, and the medulla blood flow decreased. On the other hand, in the nonpulsatile group, both regional blood flows decreased. That means that in the pulsatile assisted group intrarenal redistribution improved rather than in the nonpulsatile assisted group. In addition the liver regional blood flow, AKBR, and L/P showed significant differences between the pulsatile and nonpulsatile groups. On the other hand, the white matter and gray matter regional blood flows and carotid arterial flow did not show significant differences between the groups. The results of our study indicated that pulsatile circulation produced superior circulation in the kidney and liver, and microcirculation on the cell level was superior as well in early treatment of acute heart failure. 相似文献
58.
Full-thickness skin graft from the ulnar aspect of the wrist to cover defects on the hand and digits
Skin defects on the volar surface of the hand and digits are commonly treated with skin grafts. Many donor sites capable of providing adequate skin have already been reported. Ideal conditions for the donor site depend on skin color, texture, durability, and size. The authors describe the use of a new donor site for harvesting skin grafts to repair relatively small skin defects on the hand and digits. They used full-thickness skin grafts from the ulnar aspect of the wrist to reconstruct burn contractures and syndactyly in 20 patients. Their grafts provided an ideal color and texture match, and normal function of the hand and digits was restored. The donor site was closed directly, and the resulting scar was inconspicuous. 相似文献
59.
J. Y. Lew F. Hata T. Ohashi M. Goldstein 《Journal of neural transmission (Vienna, Austria : 1996)》1977,41(2-3):109-121
Summary Bromocriptine and lergotrile, which are clinically used as antiparkinsonian (AP) agents, compete for the binding of H3-dopamine, H3-apomorphine, and H3-haloperidol to striatal membrane sites. Lergotrile has a higher affinity for the H3-dopamine binding to bovine striatal membranes than bromocriptine. Lergotrile and bromocriptine are almost equipotent in competing for the binding of H3-apomorphine to rat striatal membranes, but bromocriptine is more potent in competing for the binding of H3-haloperidol than lergotrile. These results indicate that lergotrile and bromocriptine are mixed putative agonist-antagonist with respect to the postsynaptic dopamine receptors. Lergotrile and bromcriptine at higher concentrations inhibit synaptosomal tyrosine hydroxylase activity, and reverse the apomorphine elicited enzyme inhibition. Thus, these ergot alkaloids behave as mixed agonist-antagonist also with respect to the presynaptic dopamine receptors. Bromocriptine and lergotrile, as well as other tested DH-ergot alkaloids and neuroleptics, compete for the binding of the-antagonist H3-WB-4101 to rat cerebral cortical membranes. The displacing potencies of the tested DH-ergot alkaloids and of the neuroleptics indicate that they have a high affinity for the-adrenoreceptors in the CNS. 相似文献
60.
西洛他唑对磷脂多糖诱导的粘附及粘附分子释放的影响 总被引:1,自引:1,他引:1
目的 研究磷酸二酯酶 3型抑制剂西洛他唑对磷脂多糖 (LPS)诱导的粘附及血管内皮细胞 (ECs)释放可溶性细胞粘附分子 (sCAMs)的影响。方法 体外培养第 4~ 6代人脐静脉血管内皮细胞 (HUVECs) ,以LPS(5mg·L- 1)刺激 ,并与西洛他唑 (1~ 10 μmol·L- 1)共培养 2 4h ,观察西洛他唑对由LPS诱导的HUVECs与中性粒细胞之间的粘附的影响 ;另取培养上清 ,以ELISA法测定HUVECs释放可溶性血管细胞粘附分子 1(sVCAM 1)、细胞间粘附分子 1(sICAM 1)以及E 选择素 (sE selectin ,sELAM 1)。结果 西洛他唑抑制由LPS诱导的HUVECs与中性粒细胞之间的粘附以及HUVECs释放sVCAM 1,而对sICAM 1和sE 选择素无影响。并且 ,该药对于sVCAM 1的抑制作用被蛋白激酶A(PKA)抑制剂H 89所阻断。结论 西洛他唑对由细胞因子LPS诱导的粘附反应以及ECs释放sVCAM 1有抑制作用 ,后者可能与PKA依赖性通路相关 相似文献