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991.
992.
In order to evaluate diclofenac-Na (DC-Na) micro-enema, DC-Na gel preparations were administered to rats and man. When DC-Na gel preparations were rectally administered at various pH (pH 5– 8) to rats, their bioavailability increased at higher pH. The bioavailability of DC-Na gel preparations (pH 8.0) in rats was significantly higher than that with conventional suppository bases, Witepsol H-15 and polyethylene glycol 1000 (PEG 1000). In man, the DC-Na gel preparation showed higher Cmax and higher bioavailability than commercial suppository made with an oily base. DC-Na gel preparations containing 10% v/v oleic acid showed a prolonged action. The irritative effect of DC-Na gel preparation on rectal mucosa in rats was weaker than that of PEG 1000, but similar to that of Witepsol H-15. Therefore, the present results suggest that gel preparation is a favorable form for rectal administration of diclofenac-Na.  相似文献   
993.
Albumin microspheres as drug carriers   总被引:4,自引:0,他引:4  
In order to improve the therapeutic index in cancer chemotherapy, it is necessary to deliver antitumor agents to target sites (tumor sites). One of the methods used to deliver those agents to target sites is to employ nontoxic and biodegradable drug carriers. Considerable efforts have been directed toward the development of drug carriers, i.e., DNA complexes, protein-drug conjugates, lactic/glycolic acid polymer, liposomes, emulsion, etc. Albumin microsphere is one of those drug carriers. This review describes the progress which has been made during the last 10 to 15 years in the application of albumin microspheres as drug carriers to cancer chemotherapy. It will cover a wide range of subjects including the preparation and physicochemical properties of microspheres containing antitumor agents, pharmacokinetics of the microspheres in experimental animals, and the antitumor efficacy by intra-arterial use against human primary metastatic liver tumor.  相似文献   
994.
In a retrospective multicenter study to investigate the correlation between estrogen (ER) and/or progesterone receptors (PgR) in primary breast cancer with patient prognosis, 3118 patients with operable breast cancer (International Union Against Cancer Stages I, II, and III) were investigated from ten hospitals in Japan who underwent surgery from October 1972 to December 1982; 3089 were evaluable. The ER-positive and PgR-positive cancers were found in 56% and 34% of patients, respectively. The positivities decreased as the tumor size increased but were independent on lymph node metastasis. There were no significant differences in relapse-free survival (RFS) in relation to receptor status (median follow-up, 89 months [ER], 84 months [PgR]). However, in patients with four or more positive nodes, those with PgR-positive cancer had a longer RFS. The patients with ER-positive cancer survived significantly longer than ER-negative ones, with the greatest difference seen in those with four or more positive nodes. There was a significantly longer postrelapse survival (PRS) for patients with ER-positive cancer because of the different distribution of the major metastasis and better responses to first-line and subsequent treatments. Cox's multivariate analysis showed that overall survival but not PRS was affected by ER (and more weakly by PgR) because of the longer PRS in patients with ER-positive cancer.  相似文献   
995.
1) Plasma renin activity (PRA) response to isometric exercise was studied before and after the intravenous administration of 0.2 mg/kg of propranolol in 8 normotensive and 10 normal renin hypertensive patients. 2) Handgrip exercise at the 30% level of maximal voluntary contraction (MVC) for four minutes induced a significant increase in PRA in either normotensive or normal renin hypertensive patients, while the increase in PRA in normal renin hypertensive patients was significantly higher than that in normotensive patients. 3) Pretreatment with the administration of propranolol inhibited an increase in PRA after handgrip exercise in either normotensive or normal renin hypertensive patients. 4) The results suggest that isometric handgrip exercise can induce an augmentation in renin release mainly by stimulation of the sympathetic nervous system in either normotensive or normal renin hypertensive patients. The possible mechanism of the exaggerated response in PRA to handgrip exercise in normal renin hypertensive patients has been discussed.  相似文献   
996.
Yield of methanolic extract of fresh roots of Ginseng harvested in winter was found to be more than two-fold grater than from roots collected in summer; this remarkable increase is mainly due to the large increase of sucrose in roots in winter. On the other hand, biologically active dammarane-saponins in the roots increase in summer. These results indicate that roots should be harvested in summer for the production of high quality Ginseng extracts.  相似文献   
997.
Thirty anesthetized cats were randomly assigned to one of three groups of 10 cats each: nimodipine treatment, nimodipine treatment combined with induced hypertension, or a control group. The behavior of the cerebral pial arteries was measured by means of microscopic observation through a cranial window. The middle cerebral artery of each cat was clipped for 1 hour via the transorbital approach. Five hours after circulation was reestablished in the middle cerebral artery, Evans blue dye was injected intravenously: 30 minutes later, the animal was killed. Administration of nimodipine or saline in the treated or control group was started 5 minutes before the middle cerebral artery was clipped and maintained until the end of the experiment. Induced hypertension was produced by administration of dopamine during the occlusion. Damage to the blood-brain barrier (BBB) was judged by extravasation of Evans blue dye. Cerebral edema and infarction were evaluated from histological findings. They were most prominent in the control group: the extent of hemisphere affected was as follows (mean +/- standard error): extravasation, 40.5 +/- 8.8%; edema, 43.2 +/- 5.7%; infarction, 35.5 +/- 9.6%. On the other hand, the extravasation of Evans blue dye and cerebral edema were significantly more extensive in the group treated with nimodipine and induced hypertension (extravasation, 28.2 +/- 9.6% of the hemisphere; edema, 30.3 +/- 7.1%) than in the group treated with nimodipine alone (extravasation, 18.5 +/- 8.7% of the hemisphere; edema, 19.4 +/- 6.3%), but the infarction size was similar in both groups (16.6 +/- 4.9% of the hemisphere in the former; 17.0 +/- 6.2 in the latter).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
998.
A rupture of the ascending aorta which occurred in a woman on the 13th postoperative day following a right upper lobectomy with mediastinal lymph node dissection for lung cancer is reported herein. Fortunately, the patient was rescued from a cardiac tamponade and hemothorax by emergency operation. The operative findings suggested a traumatic rupture of the aorta, however, lymph node dissection of the mediastinum could not be excluded as a possible cause. Therefore, careful mediastinal lymph node dissection should be carefully performed in operations for lung cancer.  相似文献   
999.
The significance of the level of circulating 1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphorylcholine (C16-PAF, platelet-activating factor) in relation to transient neutropenia during hemodialysis with cuprophane membranes was examined. The neutrophil count was transiently and significantly decreased at 30 min after the start of hemodialysis, and it then gradually recovered during the period from 60 to 240 min after the start. Mirror image changes were observed in the circulating levels of C3a and C5a, suggesting that the decrease in the neutrophil count was triggered by activation of the complement factors. The circulating level of C16-PAF, although being similar to the basal level after 30 min of hemodialysis, was significantly increased after 60 and 120 min of hemodialysis. These data indicate that the increase in the circulating PAF level is not a direct cause of the transient decrease in the neutrophil count, but may be the result of activated neutrophils during hemodialysis with cuprophane membranes.  相似文献   
1000.
BACKGROUND: Primary adenocarcinomas of the vulva have been classified as sweat gland carcinomas, extramammary Paget's disease, and primary breast carcinomas of the vulva. They share some common histopathologic features. METHODS: We describe a 72-year-old Japanese woman with apocrine carcinoma of the vulva and local lymphatic metastasis. RESULTS: The patient presented with a bruise on her inguinal area. Physical examination revealed a 4 cm x 7 cm, dark-red, irregularly elevated tumor on the left labium majora. Dome-shaped, flesh-colored, small papulovesicles were scattered on the abdomen, accompanied by erythema and induration. The lesion showed a band-like arrangement. General examination revealed multiple bone metastases, particularly in the spine. Microscopic examination revealed a moderately differentiated adenocarcinoma with signet ring cells. A few pagetoid clear cells were present in the hypertrophic epidermis. The peripheral papulovesicles demonstrated the same histopathologic view as in inflammatory and telangiectatic, metastatic breast carcinoma. Tumor cells were positive for various ductal and glandular markers. Estrogen and progesterone receptors were not expressed. Ultrastructural findings suggested differentiation towards apocrine or mammary glands because of the presence of an apocrine process and electron-dense mucous granules. The patient died in spite of combination chemotherapy and irradiation therapy. CONCLUSIONS: We report a rare case of apocrine carcinoma of the vulva in a band-like arrangement with local lymphatic metastasis which showed the clinical and histopathologic characteristics of inflammatory and telangiectatic carcinoma.  相似文献   
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