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31.
Endocrine tumor of the pancreas is potentially malignant. A multicenter analysis of these tumors was conducted to clarity the present status of their surgical management and the subsequent long-term surgical results. The Japan pancreatoduodenectomy (JPD) study group carried out the study; 368 patients were enrolled and variables related to tumor characteristics, surgery, and survival were retrospectively analyzed. There were 222 patients with functioning tumor and 143 patients with nonfunctioning tumor. Malignant tumor was found in 140 of 368 (38%) of the patients, and 63/140 (45%) of these patients had metastatic lesion; the most common site of the metastasis was liver 34/136 (25%), followed by regional lymph nodes 26/136 (19%). Pancreatic resection was performed in 91% of patients with nonfunctional tumor and in 83% of those with malignant tumor, and 73% of the pancreatic resections were done with lymph node dissection. The overall 5-year actuarial survival rate was 76% in patients with malignant tumor. The actuarial 5-year survival rate was 93% in the patients without metastasis and 83% in patients who received curative resection. Multivariate analysis showed that the presence or absence of synchronous metastasis was the sole significant prognostic factor. The results suggest that: (i) malignant endocrine tumor of the pancreas is a curable malignancy when pancreatic resection with lymph node dissection is adopted and (ii) that synchronous metastasis is the dominant prognostic factor. This study was carried out as a group project. The authors' institutions are as follows  相似文献   
32.
We implanted normal peripheral blood lymphocytes (PBL) from healthy donors and splenic tissues from patients with gastric cancers into the severe combined immunodeficient (SCID) mouse, demonstrating that SCID mouse with splenic tissue can produce a high level of human immunoglobulin G (IgG). The normal PBLs at 10(7) and 10(8)/mouse were implanted intraperitoneally, and three splenic tissues with a size of 3 x 3 x 3 mm from gastric cancer patients were inoculated subcutaneously into the bilateral backs of the mice. At 2, 4, 6 and 8 weeks after inoculation, mice were killed, and the human IgG was assessed by an ELISA method. SCID mice with splenic tissue revealed high human IgG levels from 2 weeks after inoculation and approximately 2 mg of IgG per ml was observed at 8 weeks post-implantation, while the IgG levels in mice treated with PBLs were limited. Since the half life of the extrinsic human IgG was 10.2 days, the high level of human IgG in the SCID mice was supposed to be produced by human plasma cells in the splenic tissue from gastric cancer patients. This model was thought to be adequate for evaluating human immunological functions in vivo.  相似文献   
33.
Subclinical gallbladder carcinoma.   总被引:7,自引:0,他引:7  
Clinicopathologic features of 31 patients with subclinical gallbladder carcinoma were reviewed in an attempt to determine the parameters for a course of therapy. Subclinical gallbladder carcinoma was defined as a gallbladder carcinoma that was first diagnosed microscopically by surgical pathologists. Of 31 patients, there were 26 women and 5 men, ranging in age from 54 to 84 years (mean age: 68 years). All 31 patients had undergone cholecystectomy for presumed benign gallbladder conditions. The 31 gallbladder carcinomas consisted of 6 carcinomas limited to the mucosa or the muscle coat (m or pm) and 25 carcinomas extending into the subserosal layer with surgical margins free of malignant cells in 14 (ss ew [-]) and affected by malignant cells in 11 (ss ew [+]). Cumulative 1-year, 3-year, and 5-year survival rates of six patients with m or pm carcinoma were 100% (p less than 0.001, versus ss ew [+] at 1 year), 100% (p less than 0.05, versus ss ew [-] at 3 years), and 100% (p less than 0.05, versus ss ew [-] at 5 years) compared with 91% (p less than 0.01, versus ss ew [+] at 1 year), 65%, and 65% of 14 with ss ew (-) carcinoma and 43%, 0%, and 0% of 11 with ss ew (+) carcinoma. Thirteen of the 31 patients died of local recurrence and/or liver metastasis. Univariate logrank analysis of 10 prognostic factors showed that depth of invasion, venous invasion, and surgical margin were prognostic factors. Multivariate Cox-regression analysis of these three profound factors demonstrated that surgical margin and depth of invasion were independent variables. These results showed that m or pm subclinical gallbladder carcinoma does not necessarily require an additional operation, whereas ss ew (-) and ss ew (+) carcinomas necessitate additional resection and adjuvant treatment.  相似文献   
34.
The effects of fenbufen on the serum concentrations and penetration into the brain and CSF of sparfloxacin (AT-4140), a new quinolone antibacterial agent, were investigated in rats. At designated times after a bolus iv dose of sparfloxacin 10 mg/kg with or without fenbufen 20 mg/kg, arterial blood, CSF and whole brain were simultaneously collected from each rat. Sparfloxacin concentrations were assayed by HPLC. Serum concentration of sparfloxacin declined bi-exponentially with time and was not changed by coadministered fenbufen. Binding sparfloxacin to serum protein slightly decreased after the coadministration. No elevation of sparfloxacin concentrations was observed in either brain or CSF after coadministration with fenbufen except for only a few time-points. The pharmacokinetic analysis based on the physiological model indicated that fenbufen did not affect the permeability across the blood-brain or blood-CSF barrier. These results suggest that fenbufen may be unlikely to affect the pharmacokinetics, involving the entry into the central nervous system, of sparfloxacin.  相似文献   
35.
Two elderly women complaining of intermittent claudication complicated with persistent sciatic artery are herein reported. A direct femoral arteriogram showed hypoplasty of the superficial femoral artery and an unnatural anatomical relationship between the distal superficial femoral artery and the proximal popliteal artery, thus suggesting the presence of persistent sciatic artery. The diagnosis of persistent sciatic artery was finally made based on the aortography findings including the iliac arterial system and computed tomography (CT) scan. Magnetic resonance imaging (MRI) was helpful to demonstrate the entire image of this anomaly in cases with non-thrombolized sciatic artery. These diagnostic methods were useful in designing the optimal surgical strategy. The first case with a gluteal pulsating mass underwent exclusion of the persistent sciatic artery including the aneurysm through a retroperitoneal approach with a combination of femorotibial bypass, while the second case with thrombosed persistent sciatic artery only underwent femoropopliteal bypass. To recognize such a rare lesion, awareness of the differential diagnosis is important, and to provide appropriate treatment, an accurate whole image including adequate angiography, a CT scan, and magnetic resonance imaging is necessary.  相似文献   
36.
The effects of 12 essential oils, popularly used as antifungal treatments in aromatherapy, on growth of Candida albicans were investigated. Mycelial growth of C. albicans, which is known to give the fungus the capacity to invade mucosal tissues, was inhibited in the medium containing 100 micro g/ml of the oils: lemongrass (Cymbopogon citratus), thyme (Thymus vulgaris), patchouli (Pogostemon cablin) and cedarwood (Cedrus atlantica). Not only lemongrass oil but also citral, a major component of lemongrass oil (80%), in the range of 25 and 200 micro g/ml inhibited the mycelial growth but allowed yeast-form growth. More than 200 micro g/ml of citral clearly inhibited both mycelial and yeast-form growth of C. albicans. These results provide experimental evidence suggesting the potential value of lemongrass oil for the treatment of oral or vaginal candidiasis.  相似文献   
37.
N-(2-Ethylhexyl)-3-hydroxybutyramide hydrogen succinate (M-2H) has been reported to increase REM sleep. The effects of M-2H on the metabolisms of monoamines which have been implicated in the regulation of the sleep-wakefulness cycle were studied in rats. M-2H (500 mg/kg p.o.) increased the levels of 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid and 3-methoxy-4-hydroxyphenylethyleneglycol sulfate in various regions of the rat brain. However, no appreciable changes occurred in levels of serotonin (5-HT), norepinephrine, dopamine, or 3,4-dihydroxyphenylacetic acid. The effect of M-2H (500 mg/kg p.o.) on 5-HT metabolism was investigated with intraventricularly-injected [14C]-5-HT. Although [14C]-5-HT level was not significantly changed, [14C]-5-HIAA level was above control level in four brain regions such as the hypothalamus, hippocampus, midbrain and pons-medulla at 3 h after the administration of M-2H. M-2H retarded the efflux of intraventricularly-injected [14C]-5-HIAA in all brain regions except the cortex. These results suggest that M-2H preferentially impaired the transport system for acid metabolites of monoamines, resulting in increase of monoamine metabolite levels in the brain.  相似文献   
38.
2-(2,3,3-Triiodoallyl)tetrazole (ME1401), a novel antifungal agent, showed therapeutic effectiveness in topical treatment of experimental dermal infections with Trichophyton mentagrophytes and Candida albicans in guinea-pigs. Addition of diethyl sebacate to the ME1401 preparations increased its in vivo antifungal activity and its penetration into the skin. When the estimation of efficacy of treatment with active formulations was made on the basis of skin lesion and the rate of negative skin cultures in comparison with those for infected, untreated or placebo-treated controls, the in vivo activity of 0.5% ethanol tincture or gel of ME1401 was comparable to that of reference antimycotic drugs such as clotrimazole, haloprogin and others. Pharmacokinetic studies in the experimental animals demonstrated that ME1401 was unstable in vivo, being readily converted to an active metabolite 2-(3-iodopropargyl)tetrazole (CN144) first and then to 2-propargyltetrazole (CN151). CN144 showed potent in vitro and in vivo antifungal activities, while the in vitro activity of CN151 was negligible.  相似文献   
39.
A P300 (P3)-evoked response is generated in a variety of mammalian species upon detection of significant environmental events. The P3 component has been proposed to index a neural system involved in attention and memory capacity. We investigated the contribution of anterior and posterior association cortex to somatosensory P3 generation. Somatosensory event-related potentials (ERPs) were recorded in controls (n = 10) and patients with unilateral lesions in temporal-parietal junction (n = 8), lateral parietal cortex (n = 8), or dorsolateral frontal cortex (n = 10). Subjects pressed a button to mechanical taps of the fifth finger (targets; p = 0.12), randomly interposed in sequences of taps to the second (standards; p = 0.76) and the third or fourth finger (tactile novels; p = 0.06). Occasional shock stimuli were delivered to the wrist (shock novels; p = 0.06). The scalp-recorded P3 was differentially affected by anterior and posterior association cortex lesions. Subjects with temporal-parietal lesions showed markedly reduced P3s to all types of stimuli at all scalp locations. The reductions were largest at the parietal electrode site over the lesioned hemisphere. Parietal patients had normal P3s for all stimulus types except for contralateral shock novels, which generated reduced P3s. Frontal lesions had reductions of the novelty P3 over frontal sites with minimal changes in the target P3. The data support the existence of multiple intracranial P3 sources. The data further indicate that association cortex in the temporal-parietal junction is critical for generating the scalp-recorded target and novelty P3s, whereas dorsolateral frontal cortex contributes preferentially to novelty P3 generation. The N2 component was reduced by parietal and frontal lesions in patients who had intact target P3s, suggesting that different neural systems underlie N2 and P3 generation.  相似文献   
40.
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