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101.
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   
102.
103.
The acute effects of nicotine [1-methyl-2-(3-pyridyl)pyrrolidine] on the formation and resorption of bone were examined in cultures of clonal rat calvarial osteogenic cells (ROB-C26) and clonal mouse calvarial preosteoblastic cells (MC3T3-E1), as well as in osteoclast-like cells formed during coculture of mouse bone marrow cells and clonal stromal cells from mouse bone marrow, ST2 cells, at concentrations that occur in the saliva of smokeless tobacco users. Nicotine stimulated the rate of deposition of Ca(2+) by ROB-C26 cells, as well as the alkaline phosphatase activity of these cells, in a dose-dependent manner. However, both activities decreased in MC3T3-E1 cells that had been exposed to nicotine. These results indicate that nicotine affected osteoblastic differentiation in osteoblast-like cells. By contrast, nicotine reduced, in a dose-dependent manner, the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells (MNCs) and the formation of pits on slices of dentine, both of which are typical characteristics of osteoclasts. Our results suggest that nicotine might have critical effects on bone metabolism.  相似文献   
104.
The effects of a synthetic serine protease inhibitor, FOY-305, on the proliferation of normal and transformed mouse fibroblasts were investigated in vitro by MTT colorimetric assay. FOY-305 inhibited the growth of normal NIH3T3 cells and their src- and erbB2-transformed cells with a half maximum inhibitory concentration (IC50) of 1-1.2 mg/ml whereas it suppressed the growth of ras-transformed cells more effectively (IC50 was 0.5-0.6 mg/ml). Flow cytometric analysis using synchronized NIH3T3 cells has shown that the growth-inhibitory activity of FOY-305 was due to the suppression of G(1)/S transition. The synergistic effects between FOY-305 and traditional anticancer drugs were also investigated by the MTT assay and the results showed that FOY-305 significantly enhanced the antiproliferative activities of 5-fluorouracil (5-FU), 1-hexylcarbamoyl-5-fluorouracil (HCFU), 7-ethyl-1-hydroxy-7-ethyl-10-[4-(1-piperidino)-1-piperidino] camptothecin (SN-38), pirarubicin (THP) and 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU).  相似文献   
105.
106.
Prostaglandin E1-induced hypotension (25% reduction from the preadministration level in mean arterial pressure) was applied to thirteen patients. Eight patients among them were operated in the supine position (group I) and other five in the prone position (group II). The maintenance dose of PGE1 was considerably lower in group II than in group I (0.067µg·kg–1·min–1 vs. 0.119µg·kg–1·min–1). In group I, there was a significant increase in CI, with a significant decrease in SVRI and PVRI during PGE1-induced hypotension. Such a high dose of PGE1 (0.119µg·kg–1·min–1) was considered to have a direct dilating action on the systemic resistance bed as well as on the pulmonary vasculature. It was considered that the suppression of hypoxic pulmonary vasoconstriction could be a mechanism to increase venous admixture during PGE1-induced hypotension. In group II, there was no significant increase in CI, and no significant decrease in SVRI and PVRI. PGE1-induced hypotension can be safely applied to the anesthetized patients, but we should be careful to apply it to the patients in the prone position, because lower dose of PGE1 can induce severe hypotension, which is not accompanied by the increase in CI as occures in the patients in the supine position.(Hirose M, Yoda K, Sakai K, et al.: Comparative Study on the cardio-respiratory change during prostaglandin E1-induced hypotention in the patients in the supine and prone position. J Anesth 5: 30–35, 1991)  相似文献   
107.
An 18-year-old high-school boy presented facial muscle weakness since birth, and then developed wasting around the neck, shoulder girdle, upper arms, and thighs. He was born to un-consanguineous parents. His father had suffered from similar but milder muscle atrophy with predominance on the right side of the face and shoulder girdle since adolescence. His mother and his only sibling were clinically unaffected. Hearing disturbance was detected at the age of 6, and he also noted atrophy of the tongue and the bilateral thighs at the age of 10. The symptom progressed gradually. Neurological examination on admission revealed a well-developed boy (166 cm/60 kg) with a prominent facial diplegia with distinct proximal muscular atrophy of the extremities. Muscles of the tongue, neck, upper arms, shoulder and pelvic girdles, and hamstrings were markedly involved. The anterior tibial muscles were also affected, while the calf muscles were hypertrophic. High arched palate, X legs, mild lordoscoliosis were also noted. Serum CK was slightly increased (424 IU/l), and needle EMG in the extremities including the tongue revealed myopathic changes. Muscle CT demonstrated marked atrophy of the proximal muscles in the lower limbs and hypertrophy of the calf muscles. Audiogram showed bilateral sensorineural hearing disturbance. Muscle biopsy of the gastrocnemius showed myogenic as well as neurogenic changes consisting of atrophic and hypertrophic fibers with interstitial cellular infiltration, and type I fiber predominance. With these family history as well as clinical and laboratory examinations, this case could be diagnosed as "congenital facioscapulohumeral muscular dystrophy".(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
108.
To improve low-pitched voices in cases with polypoid vocal cords, YAG laser irradiation combined with a mucosal suturing technique was attempted in 9 female cases with severe polypoid changes in their vocal cords. A YAG laser beam (5 to 10 W) was used to irradiate the upper surface of the polypoid vocal cord. The polypoid content of the cord was gradually coagulated, and the free edge of the cord appeared to slide up toward the burned area. The polypoid content was then removed and squeezed through an open wound made in the burned area using a conventional method. Bleeding was successfully controlled using the laser. After the excessive mucosal margin was trimmed and the contour of the vocal cord was adjusted, the wound was closed by 7-0 monofilament absorbable suture. Suturing was relatively easy because the mucosal edge was also coagulated. Postoperative evaluations of voice quality revealed an improvement in the GRBAS scale of voice quality as well as an elevation in voice pitch and an upwards shift in the voice range in all cases.  相似文献   
109.
PURPOSE: Ewing's family tumors (EFTs) display the characteristic fusion gene EWS-Fli1. We have reported EWS-Fli1 may promote the cell cycle progression accompanied by the suppression of the expression of cyclin-dependent kinase inhibitor p27(kip1) in EFT cells. Here, we describe the prognostic and therapeutic relevance of p27 in EFTs. EXPERIMENTAL DESIGN: We examined tumor samples taken from 21 patients with primary EFTs for the expression of p27 protein immunohistochemically and evaluated its correlation with clinical outcome. We also investigated the usefulness of p27 as a therapeutic strategy in vitro and in vivo using p27 expression adenovirus. Finally, we examined the process of EWS-Fli1-mediated reduction of p27 expression. RESULTS: Immunohistochemical analysis showed that a low expression level of p27 protein was related to poor event-free survival in an univariate analysis and that the expression level of p27 correlated more significantly with patient survival than several clinical factors in a multivariate survival analysis. Overexpression of p27 with the adenoviral vector remarkably inhibited the cell growth in all EFT cells tested and further induced apoptosis in the wild-type p53 EFT cells. In vivo studies demonstrated a reduction in tumor growth of EFT xenograft in nude mice treated with the intratumoral injection of p27-expressing adenovirus. EWS-Fli1 did not significantly affect the p27 promoter activity and p27 mRNA levels. However, the challenge of the proteasome inhibitor caused accumulation of p27 protein in EFT cells. These data strongly suggest EWS-Fli1 might attenuate p27 protein level via activation of the proteasome-mediated degradation pathway. CONCLUSIONS: Our findings provide the first evidence of the prognostic relevance of p27 expression in EFTs. We propose p27 as a novel and powerful therapeutic factor for the molecular target therapy of EFTs.  相似文献   
110.
BACKGROUND: This phase I dose-escalating study investigated the tolerability and toxicity of the selective epidermal growth factor receptor tyrosine kinase inhibitor gefitinib ('Iressa', ZD1839) in Japanese patients with solid tumors. Thirty-one patients were included. PATIENTS AND METHODS: Patients initially received a single oral dose of gefitinib followed by 10-14 days of observation. Oral gefitinib was subsequently administered on 14 consecutive days, every 28 days. Dose escalation was from 50 mg/day to a maximum of 925 mg/day or dose-limiting toxicity (DLT). RESULTS: Most adverse events were mild (grade 1/2); the most frequent were an acne-like rash and gastrointestinal effects. Two of six patients at 700 mg/day had DLT; no further dose escalation occurred. C(max) was reached within 3-7 h and exposure to gefitinib increased with dose. Mean terminal half-life following multiple dosing was 50.1 h (range 27.8-79.7 h). A partial response (duration 35-361 days) was observed in five of the 23 patients with non-small-cell lung cancer over a range of doses (225-700 mg/day), and seven patients with a range of tumors had disease stabilization (duration 40-127 days). CONCLUSIONS: In conclusion, gefitinib showed a favorable tolerability profile in Japanese patients. The safety profile, pharmacokinetic parameters and antitumor activity observed in our study are comparable to those observed in patients from the USA and Europe.  相似文献   
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