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81.
Previous studies using primary monolayer cultures of epithelial cells from the involved epidermis of patients with mammary and extramammary Paget's disease investigated whether Paget cells proliferate as other malignant cells do. Although epithelial monolayers from the involved skin were maintained for approximately 45 days, no permanent cell lines were established. The proportion of carcinoembryonic antigen (CEA)-positive cells did not increase in the long-term cultures. Herein, we report studies of whether there is a real reduction of Paget cell numbers or if this is merely a decrease in the expression of CEA by the cells. Furthermore, we investigated whether Paget cells survive longer when cultured free from any potential inhibitory keratinocytes or other epidermal cells. Skin samples were obtained from one patient with mammary Paget's disease and three with extramammary Paget's disease; epidermal cells were cultured in vitro. An enrichment of Paget cells was carried out from the cultured epidermal cells by combining an anti-epithelial membrane antigen monoclonal antibody, binding to immunobeads, and density gradient centrifugation in Nycodenz. The separated cells were re-cultured in Keratinocyte-SFM serum-free media. The proportion of CEA-positive cells did not increase in the cultures, and the purified cells did not show any increase in survival times compared to the non-purified cultured cells. These results suggest that the decrease of CEA-positive cells noted during culture results from a decline in expression of CEA in the Paget cells. Paget cells in the involved epidermis do not proliferate significantly and thus differ from many other malignant cells.  相似文献   
82.
Mycosis fungoides (M.F.) is a rare cutaneous malignancy of childhood and adolescence. The disease commonly presents with the classic sequence of erythematous patches and plaques. Hypopigmentation as the presenting symptom is distinctly rare. This is the 9th case report of M.F. presenting with hypopigmentation in a patient under 20 years of age. The disease was only partially controlled with PUVA therapy, necessitating nitrogen mustard treatment.  相似文献   
83.
A 42-year-old woman with progressive myelopathy and mononeuritis multiplex is reported. The neurological examination on admission revealed hyperreflexia of the four extremities with pathological reflexes and moderate muscle weakness of the lower extremities with spasticity. Sensory disturbance was distributed on the areas of the bilateral lateral cutaneous femoral, the superficial peroneal and sural nerves. The antibody to HTLV-I in the serum and cerebrospinal fluid was more than 8192X and 512X, respectively. No sensory potential was recorded in the sensory conduction study of bilateral lateral femoral cutaneous nerves. Corticosteroid therapy caused a marked improvement of the sensory and urinary disturbances and had a slight effect on the spastic gait. Our nerve conduction study found small sensory potentials with normal conduction velocities in the bilateral lateral femoral cutaneous nerves. These results suggested the presence of an axonal degeneration in the peripheral nerves in this case. There have been no reports in the literature regarding a case of HAM with mononeuritis multiplex.  相似文献   
84.
Intestinal dialysis of drugs by oral administration of activated charcoal has been compared with peritoneal dialysis in rats. The average amounts of theophylline transported over 120 min into the intestinal lumen and the peritoneal cavity were 15.7 and 16.5% of the intravenous dose (10 mg kg-1), respectively, showing no significant difference, whereas the amount of the same intravenous dose of phenobarbitone transported from the blood into the intestinal lumen (7.8%) was significantly smaller than that entering the peritoneal cavity (12.5%). The net water flux showed that secretion predominated in the peritoneal transport whilst absorption predominated in the intestinal transport for both drugs. However, the net water flux in the intestinal lumen after intravenous theophylline (as aminophylline) was significantly smaller than that following phenobarbitone. The differences in transport across the two membranes could be due to differences in the intrinsic properties of the could be due to differences in the intrinsic properties of the membranes, such as the surface area, the thickness of the membrane and the distribution of blood vessels. Differences could also be due to differences in the pharmacological effects of the drugs.  相似文献   
85.
A 10-year experience with 2,441 patients over 65 years of age undergoing operations for non-upper gastrointestinal tracts was reviewed to evaluate both the incidence of postoperative upper gastrointestinal bleeding and the clinical risk factors associated with the complication. A total of 18 (0.7%, 7 males and 11 females) patients had overt postoperative upper gastrointestinal bleeding of non-variceal origin documented by endoscopic findings or blood transfusions. Of these, the complication developed in 10 (1.5%) of 646 patients after an operation for biliary or pancreatic disease, 1 (1.5%) of 64 for aneurysmal or obstructive arterial disease, 5 (1.1%) of 43 for colorectal cancer and 2 (0.3%) of 916 for hernia. The incidences of bleeding after an operation for obstructive jaundice (3.8%), for biliary or pancreatic malignancy (4.5%), and of unavoidable diversion colostomy for colorectal anastomosis (3.1%) were significantly higher than for non-jaundice (0.6%), for non-malignancy (1.1%) and of postoperative upper gastrointestinal bleeding in the present study. The origins of bleeding were gastric ulcer in 11, acute gastric mucosal lesion in 4, duodenal ulcer in 1 and other in 2. All cases of bleeding were treated and met success in hemostasis using H2-blockers. Of these, however, 5 patients died of multiple organ failure despite discontinued hemorrhage, prophylactic use of H2-blockers showed a decrease in occurrence of postoperative upper gastrointestinal bleeding in the present study.  相似文献   
86.
OBJECTIVE: We aimed to determine whether or not the potential distribution of the sympathetic skin response (SSR) on the palm and dorsum of the hand can be described by an equivalent current dipole (ECD) as an SSR source model. METHODS: The SSR of 22 normal subjects were simultaneously obtained from two electrodes placed on the palm and the dorsum of hand, with an indifferent electrode on the thumbnail. We then measured the SSR potential distribution in 10 of the 20 subjects who had responded to stimulation with a clear dorsal SSR. To do this, 18 electrodes were attached to the palm and dorsum of the hand. SSR-evoking stimulation (sound, voice and rapid inspiration) were randomly delivered to the subject at time intervals of more than 1min to minimize the habituation effect. We estimated the ECD from the measured potential distribution. RESULTS AND CONCLUSIONS: The SSR-evoked by stimulation was negative in potential at the palmar sites of all 22 subjects, and was positive in potential at the dorsal sites of the hand in 20 of the 22 subjects. The SSR potential distribution, which was measured in 10 subjects, reached its maximum negative and positive potential near the base of the middle finger on the palm, and near the corresponding site on the dorsum of the hand, respectively. The SSR potential measured on the dorsum of the hand, however, was about 1/3 in amplitude of those on the palmar sites. These results suggest that the SSR source is located on the palm (probably the sweat glands) as confirmed by the estimated ECD (a negative pole on the palm and a positive pole on the dorsum of the hand). We speculate that the SSR may result from the potential difference caused by the Na(+) concentration gradient in the sweat, which results from intracanal reabsorption of Na(+). SIGNIFICANCE: The ECD resulting from the Na(+) concentration gradient within the canal of sweat glands is thought to be the source of the SSR from the negative pole on the palm to the positive pole on the dorsum.  相似文献   
87.
88.
1. The effects of sarafotoxin S6c (S6c), a selective endothelin ETB receptor agonist, on renal haemodynamics and urine formation were examined in anaesthetized dogs. 2. Intrarenal arterial infusion of S6c at a rate of 1 or 5 ng/kg per min produced a transient increase in renal blood flow (RBF), with no change in systemic blood pressure and heart rate; RBF then decreased gradually to below the basal value. There were significant and dose-dependent increases in urine flow and free water clearance and decreases in urine osmolality during S6c infusion, whereas urinary excretion of sodium and glomerular filtration rate (GFR) remained unchanged. Simultaneously, S6c administration elicited a marked increase in urinary excretion of nitric oxide (NO) metabolites, N02? and N03? (UNO*V). 3. In dogs simultaneously administered S6c (5 ng/kg per min) and iVG-nitro-L-arginine (NOARG; 40 (jig/kg per min), a NO synthase inhibitor, the renal vasodilator effect of S6c was abolished and marked reductions in RBF and GFR were observed. The S6c-induced diuretic action was not affected by NOARG. In the presence of NOARG, there was a small amount of UNOxV at the basal level and the administration of S6c did not increase UNOxV. 4. These results suggest that an intrarenal arterial infusion of S6c enhances the production of NO in the kidney and that this enhancement contributes to the peptide-induced renal vasodilation. In contrast, it is unlikely that S6c-induced water diuresis is related to NO production stimulated by this peptide.  相似文献   
89.
The concentration of soluble interleukin 2 receptor (IL-2R) was determined in the serum of 54 patients with systemic lupus erythematosus (SLE) by an enzyme linked immunosorbent assay (ELISA) using two monoclonal antibodies with the IL-2R. Concentrations of soluble IL-2R in the serum of the patients with SLE (study group) were significantly higher than in 20 normal subjects (control group). The relation between concentrations of soluble IL-2R and clinical findings was investigated. The concentration of soluble IL-2R showed no particular relation with the clinical manifestations and did not correlate with the level of anti-DNA antibody or CH50. Significant correlation between the concentration of soluble IL-2R and disease activity did exist, however. Furthermore, the concentration of soluble IL-2R in some cases changed simultaneously with the disease activity. Thus the concentration of soluble IL-2R may serve as a new clinical indicator of disease activity in patients with SLE.  相似文献   
90.
A gene encoding sannamycin B-glycyltransferase (sms13) of Streptomyces sannanensis IFO 14239 was identified by cloning and complementation of S. sannanensis mutant SN13 which is blocked at the interconversion of sannamycins B and A. The cloned DNA fragment also permitted the conversion of fortimicin B to A both in S. sannanensis SN13 and Streptomyces lividans TK23. DNA sequences similar to sms13 were detected in all five producers of the fortimicin-group antibiotics, Micromonospora olivasterospora ATCC 21819 (fortimicin-producer), Micromonospora sp. strain SF-2098 ATCC 31580 (SF-2052), Dactylosporangium matsuzakiense ATCC 31570 (dactimicin), Streptomyces tenjimariensis ATCC 31603 (istamycin), and Saccharopolyspora hirsuta ATCC 20501 (sporaricin). This suggests that these genes of similar function from different genera were derived from a common ancestral gene.  相似文献   
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