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Summary Utilizing two types of human renal carcinoma heterotransplanted in nude mice, we investigated the variations in hyperthermic effects (42.5°C for 30 min) caused by differences in tumor type with special reference to variations in tumor vascularity. In the hypovascular JRC1 strain, sporadic vascular dilation was observed throughout the tumors after heating. Destruction of tumor cells was observed mainly in the region of dilation. In the hypervascular JRC11 strain, homogenous vascular dilation was observed immediately after heating, mainly at the periphery of tumors. There was a decrease in the viability of cells in the center of the tumor. Therefore, the hypervascular tumors showed greater destruction mainly at the center where blood circulation was reduced. The range of necrosis was also greatly affected by the extent of vascular dilation caused by heating in hypovascular tumors.  相似文献   
3.
T Shirakawa  Y Kusaka  N Fujimura  M Kato  S Heki    K Morimoto 《Thorax》1990,45(4):267-271
Eight asthmatic patients with hard metal asthma due to cobalt underwent bronchial provocation challenge with nickel sulphate. Seven patients developed a fall in FEV1 of 20% or more after inhaling nickel sulphate, four showing an immediate response and three a late response. Eight control subjects, including six asthmatic patients, with no history of hard metal exposure, showed no bronchoconstriction in response to a provocation challenge with nickel sulphate. Specific antibodies to nickel conjugated human serum albumin were present in four of the eight patients with sensitivity to cobalt conjugated human serum albumin but were absent from the serum of 60 unexposed asthmatic patients and 25 exposed symptom free workers. These results suggest that nickel as well as cobalt sensitivity plays a part in hard metal asthma.  相似文献   
4.
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia.  相似文献   
5.
Exposure of cultured human retinal pigment epithelial cells to platelet-derived growth factor, nerve growth factor or epidermal growth factor resulted in a time- and dose-dependent alteration in the distribution of actin stained by rhodamine-phalloidin. These growth factors (platelet-derived growth factor of 80 ng/ml, nerve growth factor of 10 ng/ml or epidermal growth factor of 10 ng/ml) caused disappearance of actin filaments from the peripheral region of a cell in 1 or 2 h and change of cell configuration to spindle shape in 3 or 4 h. Other growth factors, fibroblast growth factor of 10 ng/ml and insulin of 25 mumol/ml had no effect on actin distribution. The alteration of actin and the change of cellular shape might be associated with stimulation of cell growth and migration of retinal pigment epithelial cells.  相似文献   
6.
The effects of 5-hydroxytryptamine (5-HT) on the release of gamma-aminobutyric acid (GABA) were examined in the longitudinal muscle-myenteric plexus (LM-MP) preparation of guinea-pig ileum. 5-HT increased the spontaneous release and inhibited the electrically-evoked release of [3H]-GABA. The 5-HT-evoked release was Ca2+-dependent and tetrodotoxin-sensitive, and was antagonized by (3 alpha-tropanyl)-1H-indole-3-carboxylic acid ester (ICS 205-930), but not by methysergide and ketanserin. The inhibitory effect of 5-HT was antagonized by methysergide, but not by ketanserin and ICS 205-930. 8-Hydroxy-2-(di-n-propylamino)tetralin mimicked the inhibitory effect of 5-HT. Thus, 5-HT may exert an excitatory effect on the enteric GABAergic neurone via the 5-HT3 receptor and an inhibitory effect via the 5-HT1A receptor.  相似文献   
7.
A new doxorubicin analogue, epirubicin (EPI), was evaluated in 41 patients with acute leukemia at 11 Japanese institutions participating in a phase II study between January 1983 and July 1985; during this period 35 patients were considered evaluable. There were 25 males and 10 females with a median age of 43 years (range, 19-71 years) and the median PS of 2 (range, 0-4). EPI was given to 25 patients who had previously been treated with intensive combination chemotherapy, of whom 22 had already received anthracyclines. Ten patients had not been treated previously. Two dose schedules were explored. The higher dose schedule (18 cases) consisted of the administration of 24 to 60 mg/m2 for 3 to 5 consecutive days, and the lower dose schedule (17 cases) consisted of 11 to 20 mg/m2 for 5 to 7 days. Remissions were obtained in 7 patients (20%), 2 of whom showed complete remission and 5 partial remission. The remission duration was 2, 2, 3, 5, 16, 16 and 29+ weeks, respectively. The expected myelosuppression was universal. Stomatitis occurred in 15 patients, of which 7 cases were severe. This stomatitis occurred frequently in the higher dose schedule, and was thought to be a dose-limiting factor. In others, alopecia, G.I. symptoms, and diarrhoea (4 patients) were seen. These results from a cooperative group study indicated that EPI was an effective drug for the treatment of acute leukemia.  相似文献   
8.
Intracranial MR imaging was performed in five patients with achondroplasia. All patients had narrowing of the subarachnoid space at the level of the foramen magnum that was mainly due to protrusion of the posterior aspect. Three patients had compressive deformities of the brainstem and/or upper cervical spine. Among them, two patients had deformities of the pons. Relative upward displacement of the brainstem was seen in all patients. Hydrocephalus was seen in three patients.  相似文献   
9.
Several reports claim that portal hypertension after living-donor liver transplantation (LDLT) adversely affects graft function, but few have assessed the impact of portal venous pressure (PVP) on graft regeneration. We divided 32 adult LDLT recipients based on mean PVP during the 1st 3 days after LDLT into a group with a PVP > or = 20 mm of Hg (H Group; n = 17), and a group with a PVP < 20 mm of Hg (L Group; n = 15). Outcome in the H Group was poorer than in the L Group (58.8 vs. 92.9% at 1 year). Peak peripheral hepatocyte growth factor (HGF) during the 1st 2 weeks was higher in the H Group (L: 1,730 pg/mL, H: 3,696 pg/mL; P < .01), whereas peak portal vascular endothelial growth factor (VEGF) level during the 1st week was higher in the L Group (L: 433 pg/mL, H: 92 pg/mL; P < .05). Graft volume (GV) / standard liver volume (SLV) was higher in the H Group (L / H, at 2, 3, and 4 weeks, and at 3 months: 1.02 / 1.24, .916 / 1.16, .98 / 1.27, and .94 / 1.29, respectively; P < .05). Peak serum aspartate aminotransferase, bilirubin levels, and international normalized ratio after LDLT were significantly higher in the H Group, as was mean ascitic fluid volume. In conclusion, early postoperative PVP elevation to 20 mm of Hg or more was associated with rapid graft hypertrophy, higher peripheral blood HGF levels, and lower portal VEGF levels; and with a poor outcome, graft dysfunction with hyperbilirubinemia, coagulopathy, and severe ascites. Adequate liver regeneration requires an adequate increase in portal venous pressure and flow reflected by clearance of HGF and elevated VEGF levels.  相似文献   
10.
Antithrombin III (AT III) is known to be the most important inhibitor of serine protease in the coagulation system. In the presence of heparin, AT III is converted from its progressive activity state to an immediate activity state. In disseminated intravascular coagulation (DIC) in the field of obstetrics, the treatment has to be initiated very early. Heparin treatment, on the other hand, is critical since frequently postpartal or postoperative wound bleeding is present. We, therefore, established diagnostic criteria for the early diagnosis of DIC and investigated the clinical efficacy of a therapy with AT III in a well-controlled comparative study versus the injectable synthetic protease inhibitor FOY. The results of the trial showed that the AT III group (92%; n = 24) was significantly (p less than 0.001) superior in clinical efficacy to the FOY group (60%; n = 15). No side effects whatsoever were observed after treatment with AT III concentrate (Behring Institute). From these results, it could be concluded that a single therapy with AT III concentrate can sufficiently control the symptoms of DIC in the field of obstetrics without the risk of increased bleeding.  相似文献   
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