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91.
Breast conserving surgery and radiation therapy (RT) can achieve a more favorable cosmetic outcome than mastectomy in patients with early breast cancer. However, it is widely recognized that RT is an impediment to improving the cosmetic outcome. Between 1985 and 1993, 113 patients were enrolled in a prospective randomized study to examine whether or not RT could be avoided following sector resection in patients with Stage I and II (UICC) invasive breast cancer. There was no significant difference in the 8 year local recurrence free survival rate between the RT and non-RT groups (92.3% versus 89.8% respectively). The characteristics of suitable patients would be negative nodes and microscopically negative resection margins. In conclusion, sector resection without RT is a reasonable option for some patients with early breast cancer.  相似文献   
92.
A single administration of ifenprodil at the doses of 100, 200 and 400 mg/kg (p.o.), and 50 and 100 mg/kg (i.m.) produced a moderate CNS depression in rats, such as, sedation, ptosis, systemic muscle relaxation and decrease in motor activity. These symptoms appeared dose-dependently and persisted for about 4 hours following administration. In a direct physical dependence test, 5 groups of rats were fed the ifenprodil-admixed food together with drinking water ad libitum for 24 hours daily for 53 approximately 103 days (mean ifenprodil intake, 43--240 mg/kg/day), on the gradedly increased dosage schedule with a dosage level of 0.5 vs. 1 mg/g food to 4 mg/g food. In the natural withdrawal following administration, no significant withdrawal signs were observed in any group. In a substitution test either for phenobarbital or morphine, no suppression of withdrawal signs during the period of cross-administration of ifenprodil and no maintenance of dependence were observed. In a physical dependence-producing test, the rats fed ifenprodil never manifested withdrawal signs such as diarrhea, "wet shakes", sudden loss of body weight as in the levallorphan precipitation test. Ifenprodil apparently has no physical dependence liability.  相似文献   
93.
Cadmium and zinc concentrations were determined in the tissues and organs, including the fetus, of striped dolphins. The kidney showed the highest cadmium concentration and the hepatic cadmium concentration was also relatively high. A similar distribution pattern among soft tissues was also observed with zinc, where its concentration varied less than that of cadmium. A significant positive correlation between zinc and cadmium was found in both the kidney and the liver; the increase of zinc concentration with cadmium was more marked in the liver (Zn:Cd 3∶1 on molar basis) than kidney (Zn:Cd 1∶1). Negligible cadmium concentration in the fetus suggested that cadmium is not transferred to the fetus via the placenta from the mother. Organ-specific age trends of cadmium and zinc concentrations were presented in detail for muscle, liver, kidney, pancreas, brain, and blood. Both metals showed rapid change during the periods of the fetus and weaning.  相似文献   
94.
Summary Aprindine is a class Ib antiarrhythmic agent. We studied effects of aprindine (3 µmol/l) on the Na+ current using whole cell voltage clamp (tip resistance = 0.5 , [Na]i ando = 10 mmol/l at 18°C). Aprindine revealed tonic block (Kdrest = 37.7 µmol/l, Kdi = 0.74 µmol/l; n = 4). Aprindine, shifted inactivation curve to hyperpolarizing direction by 11.4 ± 3.5 mV (n = 4) without changes in slope factor. In the presence of 3 µmol/l aprindine, aprindine showed phasic block, i.e., duration-dependent block at 2 Hz (64% ±3070 at 1.5 ms, 82%±6% at 20 ms, 93%±7% at 200 ms; n = 4). Short single prepulse also produced aprindine-induced phasic block (12% at 1.5 ms, 22% at 100 ms; n = 2). After removal of fast inactivation of Na+ current by 3 mmol/l tosylchloramide sodium, aprindine revealed phasic block, independent of holding potential. The recovery time constant from aprindine-induced phasic block was 4.8 s at holding potential = –100 mV and 5.0 s at holding potential = –140 mV. This use-dependent block of aprindine had pH dependency. Under acidic condition (pH 6.0), 3 µmol/l aprindine showed smaller use-dependent block (14% ± 7% at 2 Hz; n = 4) comparing with either at pH 7,4 (68% ± 13%; n = 4) or at pH 8.0 (90% ±12%; n = 4).The results suggest that aprindine could bind to the receptor via activation process through channel pore, resulting in decrease of Na+ current, and egress from the receptor through the lipid bilayer. These effects might be attenuated under acidic condition due to changes in intracellular ratio of charged to neutralized form of drug molecule. Send offprint requests to: R. Sato at the above address  相似文献   
95.
The intravenous secretin injection test (secretin test) has been used for the differential diagnosis of gastrinoma. In this study we report that the intraoperative secretin test (IOS test) is also useful for determining the extent of curability in patients with Zollinger-Ellison syndrome (ZES). Twelve patients with ZES underwent surgical exploration and the IOS test. The results of the IOS test were obtained by rapid radioimmunoassay of the serum gastrin level (IRG) within 60 minutes. The test was diagnosed as negative when the maximum increase of serum IRG was less than 80 pg/ml and also less than 20% of the basal serum IRG level. Three of the twelve patients underwent pancreatoduodenectomy (PD), and two patients underwent distal pancreatectomy. Extirpation of duodenal tumors with dissection of regional lymph nodes was performed in seven patients. In two of the seven patients the IOS test remained positive after extirpation of the duodenal tumors and the dissection of regional lymph nodes. In one patient PD was performed on the basis of the positive results, and the IOS test became negative after PD. In the other patient, two tiny metastatic liver tumors were identified and were resected, but the IOS test did not become negative. We closed the abdomen in 11 patients when we obtained negative results from the IOS test. The results of the IOS test were almost identical to the data obtained by the standard assay postoperatively. The serum IRG levels of all but one patient fell to the normal level, and the secretin test became negative postoperatively. The IOS test is thus useful and indispensable for curative resection of microgastrinomas in patients with ZES.  相似文献   
96.
PURPOSE: The purpose is to assess clinical significance of matrix metalloproteinase (MMP)-2 and MMP-9 status, especially MMP-2 status, in stromal cells in non-small-cell lung cancer (NSCLC) because experimental studies have revealed that stromal MMP-2 plays important roles in progression of malignant tumors, but most clinical studies focused on tumoral MMP-2 expression, not stromal MMP-2 expression. EXPERIMENTAL DESIGN: We conducted a retrospective study on MMP-2 and MMP-9 expression as evaluated immunohistochemically in a total of 218 consecutive patients with completely resected pathological stage I-IIIA, NSCLC. RESULTS: Strong MMP-2 expression in tumor cells and stromal fibroblasts were documented in 54 (24.8%) and 132 (60.6%) patients, respectively. Strong MMP-2 expression in stromal fibroblasts was more frequently seen in squamous cell carcinoma (72.7%) than in adenocarcinoma (54.9%; P = 0.016). Tumors showing strong MMP-2 expression in stromal fibroblasts showed a significantly higher intratumoral microvessel density (IMVD) than weak stromal MMP-2 tumors (mean intratumoral microvessel density, 50.9 versus 32.4, P = 0.003). In addition, postoperative prognosis of strong stromal MMP-2 patients was significantly poorer than that of weak stromal MMP-2 patients (5-year survival rate, 77.5 versus 60.2%, P = 0.032), and the prognostic significance was enhanced in squamous cell carcinoma patients but disappeared in adenocarcinoma patients. Multivariate analyses confirmed that strong stromal MMP-2 expression was a significant factor to predict a poor prognosis in squamous cell carcinoma patients, not in adenocarcinoma patients. In contrast, MMP-2 or MMP-9 status in tumor cells was not a significant prognostic factor. CONCLUSIONS: MMP-2 status in stromal fibroblasts, not in tumor cells, was a significant prognostic factor associated with angiogenesis in NSCLC.  相似文献   
97.
To investigate the functional involvement of the pineal gland in circadian expression of the rat period homolog gene (rPer2) in the suprachiasmatic nucleus (SCN) and peripheral tissues, we performed Northern blot analysis in tissues from pinealectomized rats. The ectomy did not have any significant effects on rPer2 mRNA expression patterns both in a daily light-dark condition and in a constant darkness. These results suggest that the rhythmic secretion of pineal melatonin is not essential for the circadian expression of clock genes in the SCN and other peripheral tissues of rats.  相似文献   
98.
Although exfoliative dermatitis (erythroderma) secondary to malignancy is commonly associated with lymphomas or leukemias, coincident gastrointestinal (GI) malignancy and erythroderma is rare. The authors recently encountered a patient with gallbladder carcinoma presenting as erythroderma. A 77-yr-old Japanese man presented with a 3-mo history of erythematous eruptions with pruritus over almost the entire body. After confirming the diagnosis of erythroderma, asymptomatic gallbladder carcinoma was found. Further investigations detected no malignancies in other organs. An extended cholecystectomy was performed. Histologic examination of resected specimens revealed poorly differentiated adenocarcinoma with negative resection margins. The eruptions with pruritus resolved within 1 wk after the operation. This is the first report, to our knowledge, of coincident biliary malignancy and erythroderma. The experience of the current patient suggests that erythroderma secondary to GI malignancy may resolve spontaneously after curative resection of the tumor.  相似文献   
99.
The "glove" phenomenon is caused by arterial injection of a bone-imaging agent into the antecubital fossa. The authors describe a patient who incidentally received an arterial injection of bone-imaging agent into the right distal radial artery near the wrist, which resulted in a "hot" palm and thumb. The phenomenon of hot palm and thumb can be explained by normal anatomic-physiologic blood flow after radial artery injection. The radial artery contributes the blood supply to the thumb through the dorsal metacarpal arteries of the first metacarpals, and the dorsal carpal branch of the radial artery, a branch of the interosseous artery, and dorsal carpal branch of the ulnar artery form the dorsal carpal rete. The normal vascular anatomic-physiologic dynamic constituted the mixture and dilution effects after the distal radial artery injection that resulted in hot areas limited to the palm and thumb of the hand on bone scintigraphy.  相似文献   
100.
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