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51.
During the anhepatic phase of orthotopic liver transplantation, the veno-venous bypass has been used to keep systemic hemodynamics (SHD) in a stable condition. In this study, changes of SHD and oxygen transport and consumption (OTC) during the anhepatic phase used the passive bypass (PB) with Anthron bypass tubes were compared with those used the pump-driven bypass (PDB) with a centrifugal pump in mongrel dogs. Moreover the effects of the increased instillation rate and administration of dobutamine on SHD and OTC were evaluated. The portal venous and inferior vena caval pressure were increased in PB group, but not in PDB group. Whenever PB or PDB was used, cardiac index and oxygen consumption were markedly decreased caused by hypovolemia. In PDB group trebled the instillation rate, SHD and oxygen consumption were not improved. These results suggested that the primarily cardiovascular depression during the anhepatic phase was related to the disturbance of SHD. When dobutamine was administered and the instillation rate was trebled in PDB group, SHD and OTC were maintained in a favorable state. It is concluded that PDB, administration of dobutamine and sufficient instillation are advantageous to maintain systemic hemodynamic stability during the anhepatic phase of orthotopic liver transplantation. 相似文献
52.
Effects of microwave-induced whole-body hyperthermia (WBH) on the mouse kidney were examined histologically for acute and late effects up to 150 days after WBH treatment at 43.5 degrees C (rectal temperature) for 20 min or 42 degrees C for 40 min. As a whole the damage could be divided into two types. One was the damage to distorted epithelial cells in the subcapsular region. This lesion was common in most animals, possibly caused by direct hyperthermic effect of microwave. The other was general renal atrophy accompanied with aqueous or protein-rich cysts due to a chain of physiological reactions of the whole body to WBH. The first reaction was characterized by general stasis of the blood stream in all parts of the kidney, which resulted in acute ischemia of some tissues. This was seen immediately by dilatation of the renal and interlobular veins as well as the bundles of capillaries in the medulla region. The subsequent event was rather specific cell necrosis of distal and collecting tubular epithelium as compared to proximal tubules. The cell destruction induced cell proliferation of the proximal tubular epithelia after two days. Later on, in accord with the recovery of the blood circulation, the proliferated cells were carried away into the lumen, these processes then resulting in obstruction of tubules through formation of protein casts in the lumen. The block incidentally led to the destruction of nephrons. The degenerated area sometimes consisted of aqueous or protein-rich cysts of various sizes after 7 to 30 days. Thereafter these cysts degenerated, decreasing in both number and size. Thus irreversible atrophy of the kidney developed after WBH. 相似文献
53.
54.
A cerebral type of Lewy body disease (LBD) is proposed. Lewy body disease was split formerly into three types: brainstem type, transitional type and diffuse type. The diffuse type is now called diffuse Lewy body disease (DLBD). These three types are characterized pathologically by the presence of a large number of Lewy bodies in the CNS. In the brainstem type, Lewy bodies are numerous in the brainstem and diencephalon nuclei, and in DLBD, a vast number are present not only in these nuclei but also in the cerebral cortex and amygdala. In the cerebral type of LBD, as many Lewy bodies are found in the cerebral cortex and in the amygdala as there are in DLBD, but only rarely are they present in the brainstem and diencephalon nuclei. Thus, this type of LBD is different from other types in that it has no parkinson pathology. Therefore, parkinsonism fails to occur throughout the whole clinical course of this disease. The existence of a cerebral type of LBD suggests that Lewy bodies occur in the cerebral cortex earlier than in the brainstem nuclei and that cortical Lewy bodies appear even when the mesocortical dopaminergic system is intact. In addition, this might explain why dementia frequently precedes parkinsonism in DLBD. 相似文献
55.
Koichi Akamatsu Soichiro Miyauchi Kenji Ohshima Shunji Okita Yoshifumi Yasuhara Hiroshi Mogami Yasuyuki Ohta Ken Hamamoto 《Cancer chemotherapy and pharmacology》1989,23(Z1):S59-S64
Transcatheter arterial embolization (TAE) with the concurrent use of caerulein was assessed for the purpose of preventing gallbladder complications often seen after TAE of hepatic carcinoma. Ninety-six cases with primary hepatic carcinoma, who had undergone TAE in the right hepatic arterial region over the past 4 years, were divided into three groups: 22 cases for which embolization was possible on a selective basis by passing the catheter to the peripheral side beyond the bifurcated region of the cystic artery; 40 cases who had undergone TAE in which caerulein was not administered, from the central side of the bifurcated region of the cystic artery; and 34 cases given 20 g caerulein 15–30 min before TAE. A comparison was made using the abdominal pain, pyrexia, rate of leukocytosis and the US findings of the gallbladder as the indices of the gallbladder complications. As a result, it become evident that it was possible to prevent or alleviate gallbladder complications if caerulein were administered before TAE in cases where the embolizing substances were infused in the right hepatic artery from the central side of the bifurcated region of the cystic artery. It was conclusively shown that the gallbladder blood flow decreases if the organ is contracted by caerulein, which in turn causes a decrease in the inflow of the embolizing substances whereby complications are alleviated. 相似文献
56.
Association of the insertion/deletion polymorphism of the angiotensin I-converting enzyme gene in patients of migraine with aura 总被引:2,自引:0,他引:2
Kowa H Fusayasu E Ijiri T Ishizaki K Yasui K Nakaso K Kusumi M Takeshima T Nakashima K 《Neuroscience letters》2005,374(2):129-131
Recently, several angiotensin I-converting enzyme (ACE) inhibitors and an angiotensin II receptor blocker were demonstrated to have a clinically important prophylactic effect in migraine. ACE is one of the key enzymes in the rennin-angiotensin-aldosterone system, which modulates vascular tension and blood pressure. In humans, serum ACE levels are strongly genetically determined. Individuals who were homozygous for the deletion (D) allele showed increased ACE activity levels. To investigate the role of ACE polymorphism in headache, we analyzed the ACE insertion (I)/deletion (D) genotypes of 54 patients suffering from migraine with aura (MwA), 122 from migraine without aura, 78 from tension-type headache (TH), and 248 non-headache healthy controls. The ACE D allele were significantly more frequent in the MwA than controls (p<0.01). The incidence of the D/D genotype in MwA (25.9%) was significantly higher than that in controls (12.5%; p<0.01; odds ratio=5.26, 95% confidence interval: 1.69-16.34, adjusted for age and gender). No differences in the remaining groups were found. Our results support the conclusion that the D allele and the D/D genotype in the ACE gene is a genetic risk factor for Japanese MwA. There seems to be a possible relationship between ACE activity and the pathogenesis of migraine. 相似文献
57.
58.
Masaharu Muranaka Shuji Suzuki Kazuhiro Koizumi Hiroshi Igarashi Hiroshi Okumura Koyo Takeda Kenji Tadokoro Yoshihiko Horiuchi 《The Journal of allergy and clinical immunology》1978,62(5):276-282
All of the five commercially available benzylpenicillin preparations obtained from different sources and a PcG preparation prepared by filtration of a commercial PcG on Sephadex G10 elicited the systemic anaphylactic reactions in guinea pigs which had been immunized with benzylpenicilloyl (BPO)-Ascaris extract conjugate (BPO-As) mixed with aluminum hydroxide gel. These preparations could evoke no such reactions in guinea pigs immunized with BPO-bovine gamma globulin conjugate (BPO-BGG) emulsified with complete Freund's adjuvant. The severity of the systemic anaphylactic reactions correlated significantly with the titers of either 8-day passive cutaneous anaphylactic (8-day PCA) reactions or 4-hr PCA reactions evoked with the same benzylpenicillin preparations. In vitro benzylpenicillin preparation contracted the tracheas of the guinea pigs immunized with BPO-As. These results indicated that the commercially available benzylpenicillin preparations have enough antigenicity to evoke systemic anaphylactic reactions in guinea pigs immunized with BPO-As mixed with aluminum hydroxide gel. Such guinea pigs represent an animal model for investigation of penicillin allergy. 相似文献
59.
Satoshi Mochida Itsuro Ogata Yasuhiko Ohta Teruaki Oka Kenji Fujiwara 《Pathology international》1991,41(3):217-220
In order to investigate superoxide production by pulmonary macrophages in the rat, a route was created by ligating both the inferior and superior venae cavae and resecting the aorta after cannulation through the inferior vena cava into the right atrium of the heart. Lung perfusion was performed via this route with nitro blue tetrazolium. Although there was no formazan deposition throughout the lung, it became detectable in both alveolar and interstitial macrophages when phorbol myristate acetate was added to the perfusate. This deposition was markedly enhanced by previous injection of Corynebacterium parvum. The deposition disappeared after further addition of Cu(Lys)2 , a scavenger of superoxide anions. This procedure may be useful for estimating in situ the ability of pulmonary macrophages to produce superoxide in the rat. 相似文献
60.
Kenji Moriyama Kazuko Iida Ichiro Yahara 《Genes to cells : devoted to molecular & cellular mechanisms》1996,1(1):73-86
Background: Cofilin is a low-molecular weight actin-modulating protein, and is structurally and functionally conserved in eucaryotes from yeast to mammals. The functions of cofilin appear to be regulated by phosphorylation and dephosphorylation. Results: A proteolytic study of phosphorylated porcine cofilin and expression of a mutated cofilin in cultured cells revealed that Ser-3 is the unique phosphorylation site. Phosphorylated cofilin was found not to bind to either F-or G-actin while unphosphorylated cofilin binds to both. S3D-cofilin, in which Ser-3 was replaced with Asp, did not bind in vitro to actin while S3A-cofilin did. The transient overexpression of wild-type or S3A-cofilin in cultured cells caused disruption of pre-existing actin structures and induced cytoplasmic actin bundles. Heat shock-induced nuclear or NaCl buffer-induced cytoplasmic actin/cofilin rods contained the expressed cofilin. In contrast, the overexpression of S3D-cofilin did not alter the actin structures. Induced actin rods did not contain S3D-cofilin. S3D-porcine cofilin did not complement the lethality associated with Δcof1 mutations in Saccharomyces cerevisiae while wild-type and S3A-cofilin did. Furthermore, we found that S2A/S4D- and S2D/S4D-yeast cofilin mutants were not viable. Conclusion: We conclude that the function of cofilin is negatively regulated in vivo by phosphorylation of Ser-3 and that cells require the functions of unphosphorylated cofilin for viability. 相似文献