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111.
112.
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   
113.
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   
114.
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   
115.
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   
116.
Frequent expression of bcl-2 protein in solitary fibrous tumors   总被引:3,自引:0,他引:3  
The distinction of solitary fibrous tumors from histologically similar neoplasms is often difficult because they rarely occur at a variety of extrapleural sites. CD34 immunoreactivity has recently been recognized to be an adjunct for the diagnosis of solitary fibrous tumors. However, it is now known that CD34 staining is not entirely specific for this entity. We evaluated 23 solitary fibrous tumors and 54 other spindle cell tumors often considered in the differential diagnosis for immunoreactivity using monoclonal antibodies directed against bcl-2 protein, which protects cells from apoptosis and CD34. The patients with solitary fibrous tumors comprised 11 men and 12 women, ranging in age from 35 to 85 years (mean, 57.6 years). Fourteen tumors arose in the pleura, four in the retroperitoneum, three in the superficial soft tissue and one each in the mediastinum and uterine cervix. Nineteen of 23 solitary fibrous tumors (83%), irrespective of tumor site, demonstrated diffuse cytoplasmic staining for bcl-2 protein. bcl-2 immunoreactivity was also observed in five of seven neurofibromas (71%), eight of 10 synovial sarcomas (80%) and one of three spindle cell lipomas (33%). CD34 immunoreactivity was present in all but one solitary fibrous tumor (96%), seven of seven neurofibromas (100%), three of three spindle cell lipomas (100%), five of five dermatofibrosarcomas (100%), three of three hemangiopericytomas (100%) and two of seven malignant fibrous histiocytomas (29%). To date, most of the pleural and extrapleural cases have not shown aggressive features. We suggest that bcl-2 protein can be used together with CD34 in the diagnosis of solitary fibrous tumor to distinguish this entity from other spindle cell neoplasms.   相似文献   
117.
To know the potential of growth, invasion and metastasis of uterine endometrial cancer associated with neovascularization, the expressions of VEGF and its mRNA, especially their subtypes, in uterine endometrial cancers and normal uterine endometria as controls were determined by Western blot analyses with a sandwich enzyme immunoassay and RT-PCR-Southern blot analysis, respectively, and the relation between their expressions and histological grades, grades of myometrial invasion and clinical stages of uterine endometrial cancers was analyzed. The levels of VEGF (VEGF165 and VEGF121) protein and mRNA were in a wide range and higher in normal uterine endometria than in the malignant counterparts. The levels of VEGF protein were higher in order of histopathological differentiation (normal uterine endometrium > well-differentiated (G1) > moderately differentiated (G2) and poorly differentiated (G3)) and those of VEGF protein and VEGF121 mRNA were lower in order of the advance of clinical stages (normal uterine endometrium > stage I > stage II > stages III and IV). There was, however, no significant difference in their levels among uterine endometrial cancers classified according to grades of myometrial invasion. This suggests that VEGF is downregulated during uterine endometrial cancer progression with dedifferentiation. Namely, VEGF in some endometrial cancers might contribute to the early process of advancing of malignancy via angiogenic activity.  相似文献   
118.
Agaricus blazei Murrill, an edible mushroom, is widely used as a functional food due to its possible medicinal effects. Aqueous extracts are also used as food additive to provide an agreeable bitter taste. As a part of its safety assessment, the present 90-day subchronic toxicity study was performed in F344 rats. To establish a no-observed-adverse-effect level (NOAEL), rats were fed powder diet containing A. blazei Murrill aqueous extract at dose levels of 0 (basal diet), 0.63, 1.25, 2.5 and 5% (maximum) for 90 days. During the experiment, there were no remarkable changes in general appearance and no deaths occurred in any experimental group. Although serum blood urea nitrogen was slightly but significantly increased in males of the 2.5 and 5% groups, no related histopathological changes were observed in the kidney, and serum creatinine levels were rather reduced, suggesting the increase of blood urea nitrogen to be of little toxicological significance. Hematology, organ weight measurement and histopathological observation revealed no test compound-related toxicological changes. In conclusion, A. blazei Murrill extract even at 5% in the diet (2654 mg/kgb.w./day for male rats and 2965 mg/kgb.w./day for female rats) did not cause remarkable adverse effects in F344 rats. Thus, the NOAEL was concluded to be 5% in the diet.  相似文献   
119.
To investigate the mechanism of chronic cell death following postischemic hypothermia, the change of N-methyl- -aspartate receptor (NMDAR) were examined by immunohistochemistry of NMDAR1 and long-term potentiation (LTP) in the CA1 subfield of the gerbil hippocampus. At 1 week following postischemic hypothermia (32°C×4 h), all CA1 neurons survived; however, immunoreactivity of NMDAR1 increased in neuronal perikarya whereas decreased in dendrites in the CA1 neurons. The abnormality was still observed in remaining CA1 neurons at 1 month after hypothermia. LTP was also significantly depressed at 1 week after hypothermia. These results suggest that some abnormalities in the glutamate receptor may be caused by ischemia; such abnormality would persist in spite of hypothermia treatment, resulting in the depression of LTP.  相似文献   
120.
Cells of oligodendroglial lineage are susceptible to oxygen and glucose deprivation. When oligodendrocyte-like cells differentiated from CG-4-immortalized rat O-2A progenitor cells were exposed to hypoxia alone or glucose deprivation alone for 48 h, release of lactate dehydrogenase (LDH) into the culture medium did not increase. However, when cells were deprived of both oxygen and glucose for 6 or 12 h preceding reoxygenation for 2 h, LDH release increased. Adding glucose to the medium protected against cell death and increased lactate production in a concentration-dependent manner. Cell damage induced by deprivation of oxygen and glucose was prevented by calcium-free medium or by non-N-methyl-D-aspartate glutamate receptor (GluR) antagonists, such as 6-cyano-7-nitroquinoxaline-2,3-dione or LY293558, but not by the voltage-dependent calcium channel blocker, nimodipine, or by the N-methyl-D-aspartate GluR antagonist, MK-801. The glutamate concentration in the medium from cells exposed to oxygen-glucose deprivation for 12 h was 49.70+/-3.04 microM/l, which is sufficient to activate GluRs during deprivation of oxygen and glucose. Apoptotic cells detected by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end-labeling (TUNEL) or Hoechst 33258 staining did not increase in cells exposed to oxygen-glucose deprivation for 12 h and subsequent reoxygenation for 2 h. No DNA laddering was detected by agarose gel electrophoresis from cells exposed to deprivation of oxygen and glucose. Neither acetyl-YVAD-CHO, an inhibitor of caspase-1-like proteases, nor acetyl-DEVD-CHO, an inhibitor of caspase-3-like proteases, prevented oxygen-glucose deprivation-induced injury. Thus, oxygen and glucose deprivation causes calcium-influx-induced necrotic cell damage in cells of oligodendroglial lineage via non-N-methyl-D-aspartate GluR channels.  相似文献   
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