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53.
Arterial blood ketone body ratio (AKBR; acetoacetate/beta-hydroxybutyrate) is known as a parameter to indicate the function of the liver cells. We evaluated the effects of induced hypotension with prostaglandin E1 (PGE1) or trimetaphan (TMP) on AKBR in patients without liver disease undergoing mastectomy. Almost no change was observed in AKBR before, during and after hypotension with PGE1, but slight diminution was observed during hypotension with TMP. No hepatic dysfunction, however, developed in these patients postoperatively. These findings suggest that usual hypotension with TMP may provoke no postoperative hepatic dysfunction in patients without liver disease. For the patient who required either hypotension of long duration or hypotension with other factors affecting function of liver (surgical procedures, drugs and others), we prefer PGE1 to TMP as a hypotensive drug. We should also adopt PGE1 when cardiovascular control with hypotensive drug is necessary in patients with liver disease.  相似文献   
54.
With the purpose of obtaining more potent and selective gastric prokinetic than metoclopramide (1), a new series of N-[(2-morpholinyl)alkyl]benzamides (17-52) were synthesized and their gastric prokinetic activity was evaluated by determining effects on the gastric emptying of phenol red semisolid meal and of resin pellets solid meal in rats and mice. The morpholinyl moiety was newly designed after consideration of the side-chain structure of cisapride (2) and produced the desired activity when coupled with the 4-amino-5-chloro-2-methoxybenzoyl group of both metoclopramide and cisapride. Modification of the substituents of the benzoyl group markedly influenced the activity. In particular, 4-amino-N-[(4-benzyl-2-morpholinyl)methyl]-5-chloro-2-methoxybenzamide (17) and the 4-(dimethylamino) and 2-ethoxy analogues (25 and 29) of 17 showed potent and selective gastric prokinetic activity along with a weak dopamine D2 receptor antagonistic activity.  相似文献   
55.
The kapurimycins A1, A2 and A3 were revealed to be new antitumor antibiotics with molecular formula of C27H26O9, C26H24O9 and C27H24O9, respectively. The structures of the kapurimycins were determined by NMR spectroscopic analysis. The kapurimycins are new class of polycyclic microbial metabolites having the tetrahydroanthra-gamma-pyrone skeleton and the beta, gamma-unsaturated delta-keto carboxylic acid structure. The individual components of the kapurimycins differ from one another in the side chain at the pyrone ring of the molecule.  相似文献   
56.
The cell body size (cross-sectional area) of S100-immunoreactive (-ir) primary neurons was measured in the trigeminal (TG) and lumbar dorsal root ganglia (DRG). About a half of neurons exhibited S100-immunoreactivity (-ir) in the DRG (44.0%) and TG (59.0%). DRG neurons with cell bodies >1200 μm2 mostly exhibited S100-ir (96.5%), whereas S100-ir DRG neurons <600 μm2 were rare (8.0%). 36.6% of DRG neurons in the cell size range 600–1200 μm2 showed the ir. TG neurons >800 μm2 mostly exhibited S100-ir (93.1%), whereas those <400 μm2 were devoid of it (positive cells 10.5%). 58.3% of TG cells in the range 400–800 μm2 contained S100-ir. Double-immunofluorescence method revealed the co-expression of S100 and other calcium-binding proteins. Parvalbumin-ir neurons mostly exhibited S100-ir in the DRG (97.4%) and TG (97.0%). The co-expression of S100 and calbindin D-28k was very rare in the DRG, because the DRG contained few calbindin D-28k-ir neurons. Unlike in the DRG, numerous neurons co-expressed S100- and calbindin D-28k-ir in the TG. Most calbindin D-28k-ir TG neurons were also immunoreactive for S100 (90.7%). Sub-populations of calretinin (CR)-ir neurons co-expressed S100-ir in both the DRG (68%) and TG (50.0%). Virtually all CR-ir neurons >1400 μm2 co-expressed S100-ir in the DRG (100%) and TG (95.9%). CR-ir neurons <800 μm2 were rarely exhibited S100-ir (DRG 18.0%, TG 21.9%). 71.3 and 60.5% of CR-ir neurons in the range 800–1400 μm2 co-expressed S100-ir in the DRG and TG, respectively. The present study indicates that S100 is closely correlated to the primary neuronal cell size in the DRG and TG.  相似文献   
57.
Hepatocyte regeneration has been widely investigated, with the mitotic index and the incorporation of [3H]thymidine being used as regeneration markers. We focused on the induction of DNA replication enzymes, particularly DNA polymerases (pol) α, δ, and ε. Using rat models, we have shown that the activity of pol α in crude liver extract well represents the regenerating capacity of hepatocytes. Using pol α as an indicator, we analyzed liver regeneration in rat models under various conditions: obstructive jaundice, external or internal biliary drainage, and the obstruction of portal vein branches. It has been revealed that the ligation of the common bile duct alone induces a certain amount of hepatocyte proliferation. It was striking that external biliary drainage suppressed regeneration capacity in cholestatic rat liver after partial hepatectomy. The strong regeneration in nonligated lobes induced by portal branch ligation was similar to the liver regeneration seen after partial hepatectomy with respect to the induction of DNA polymerases. Taken together, the aspects of DNA replication, particularly the induction of DNA polymerases, may contribute to shedding new light on the regeneration of human liver. This work was supported in part by a Grant-in-Aid for General Scientific Research and for Cancer Research from the Ministry of Education, Science and Culture, Japan, and by grants from the Uehara Memorial Foundation  相似文献   
58.
We examined radiographs of the elbows of the pitching arms of 79 professional baseball pitchers (mean age, 25.1 years; mean duration of professional career, 4.7 years) and noted the frequency and size of spurs, bone fragments, and intra-articular loose bodies according to site. The influence of duration of professional baseball career on these osteoarthritic changes was also investigated. The olecranon tip was the most frequent site of spurs (62/79; 78.5%), and fragmentation of the spur was detected in 17 joints. The frequency of spurs was also high at the medial margin of the olecranon, the tip of the coronoid process, the medial margin of the sigmoid notch, the medial margin of the trochlea and the olecranon fossa. In 38 subjects, spurs were observed at the distal portion of the radial notch of the ulna. However, few pitchers had osteoarthritic changes in the humeral capitellum or radial head. Intra-articular loose bodies were detected in 4 of 79 joints (5.1%), and bone fragments were present below the medial humeral epicondyle in 25 of 79 joints (31.6%). Osteoarthritic changes in the elbow joint appeared to be attributable mainly to traction stress and impingement associated with extension and valgus strain. Significant osteoarthritic changes were often found in professional pitchers whose careers exceeded 5 years.  相似文献   
59.
Immunopathogenicity of trypsin-solubilized or non-solubilized renal tubular basement membrane (TBM) of the Lewis (LEW) rat was investigated. Autoimmune tubulointerstitial nephritis (TIN) was induced in BALB/c mice by immunization with trypsin-solubilized LEW rat TBM, while immunization with non-solubilized TBM did not produce the disease. Based on this preliminary experiment we studied the characterization of immunogenic and nephritogenic TBM antigen of the LEW rat. TIN was characterized by severe mononuclear cell infiltrates with multi-nucleated giant cells in the interstitium, tubular destruction and intensive IgG and C3 deposits along the TBM. Anti-TBM antisera and eluate from the nephritic mouse kidneys reacted with the TBM of normal LEW rat kidney by immunofluorescence. LEW rat TBM was also detected immunofluorescently by using antisera from BALB/c mice immunized with autologous trypsin-solubilized TBM. A competitive inhibition test revealed a higher titer of anti-TBM antibody in the eluate than in the adsorption-treated antisera per microgram IgG. Immunoblotting showed one reactive band with a molecular weight of 45,000 daltons, and the blotting patterns in tryptic TBM of the Brown Norway (BN) and LEW rats appeared similar. Amino acid analysis of nephritogenic LEW rat tryptic TBM showed that it contained no hydroxyproline and hydroxylysine, suggesting that this TBM preparation was not collagenous. These findings suggest that tryptic digestion contributes to the release of nephritogenic antigen from the LEW rat TBM and that this antigen system might participate in the immune system involved in the anti-TBM associated TIN that is well known to be induced by non-digested TBM of TBM antigen positive animals.  相似文献   
60.
Three xenografts established from three patients with anaplastic thyroid carcinoma were investigated for their biological characteristics and chemosensitivity. The histological and immunohistochemical findings of these tumors were almost the same as those of the original tumors. Although the growth rate of each xenograft was constant, the tumor doubling time varied from 4.8 per 9.0 days, and the labeling indexes, determined using bromodeoxyuridine pulse labeling, varied from 11.4 to 25.1 per cent. The chemosensitivity tests were performed according to the Battelle Columbus Laboratories Protocol, with adriamycin, cyclophosphamide, cisplatin, mitomycin C and tegafur administered intraperitoneally to tumor-bearing nude mice in maximum tolerable doses. Tumors with slower growth rates tended to be sensitive to more drugs. Furthermore, cyclophosphamide showed antitumor effects against all the tumors tested. Although previous treatments of the original tumors may have affected the results, our results suggest that a more suitable chemotherapy for anaplastic thyroid carcinoma could be developed.  相似文献   
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