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51.
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   
52.
There is no definitive surgical procedure for acquired lesions of the tricuspid valve (TV). From Feb, 1978, through March, 1990, the surgical treatment for the organic lesions of TV was performed in 10 patients, repair in 6 and TV replacement in 4. TV was repaired by commissurotomy, annuloplasty or valvuloplasty, or combination of them. When residual significant tricuspid regurgitation (TR) and/or stenosis (TS) was detected by intraoperative pulsed Doppler echocardiography after reparative procedures, TV was replaced. Follow-up periods ranged from 1 to 12 years (mean, 45.3 months). There was no early death, and late death was noted in one patient 32 months after operation. Preoperatively, 7 patients were in NYHA class IV and 3 in class III. Out of survivors, 7 are in class I and 2 in class II because of progression of mitral stenosis or coronary artery disease. Following surgery, the patients exhibited significant decrease in the cardiothoracic ratio (69.3 +/- 7.2 to 56.9 +/- 6.4%; p less than 0.01) and in the mean right atrial pressure (11.4 +/- 3.6 to 8.6 +/- 3.1 mmHg; p less than 0.05). The postoperative right ventriculography showed mild to moderate TR in 3 of 6 patients who underwent TV repair. In conclusion, TV repair could be a reasonable procedure for the organic TV lesions, although careful follow-up is recommended for residual TR.  相似文献   
53.
We report the case of a patient with delayed methotrexate (MTX)-induced leukoencephalopathy who showed a marked improvement both in clinical and neuroimaging findings after a high-dose of the active form of folinic acid (leucovorin) treatment. The patient developed progressive affective impairment accompanied by headache, nausea and vomiting after treatment with MTX during the chemotherapy for acute lymphoblastic leukemia, and diagnosed as delayed type MTX-induced leukoencephalopathy. After an intravenous injection of high-dose folinic acid (total 1920 mg), neurological deficits and white matter changes dramatically improved in a few weeks. Although delayed MTX-induced leukoencephalopathy may cause irreversible brain damage, an early treatment with high dose leucovorin may thus facilitate the marked improvement of clinical findings and white matter abnormalities.  相似文献   
54.
To elucidate the penetrability of carteolol, a β-adrenoceptor antagonist (β-blocker) into the brain of rats, intracerebral and serum concentrations of the compound were determined in male rats receiving single or repetitive oral administration of carteolol hydrochloride at 30 mg/kg. The time-course of the intracerebral concentration of carteolol following single IV administration of the compound at 10 and 30 mg/kg was also studied in male rats. A high-performance liquid chromatography method was used to determine the intracerebral and serum concentrations. Following single oral dosing, the intracerebral concentration of carteolol reached a maximum of 0.074 μg/g at 2 h postdosing and declined with a half-life of 3.7 h, and the Cmax and AUC of carteolol in the brain were 12.5% and 19.8% of those in serum. The intracerebral and serum concentrations of carteolol were determined in male rats receiving repetitive oral dosing of the compound once daily for 7 days. The concentration of carteolol in the brain and serum at 1 h postdosing varied within a range of 0.059–0.091 μg/g and 0.321–0.443 μg/ml, respectively, throughout the dosing period, showing no changes in the penetrability of the compound into the brain due to repeated dosing. The concentration of carteolol in the brain and serum increased in a dose-dependent manner in rats receiving a single IV administration of the compound. The elimination half-life of carteolol in the serum and brain was 0.6–0.8 h and 1.3–1.7 h, respectively, in rats following single IV dosing of the compound. The half-life in the brain was about twice as long as that in the serum. The brain to serum concentration ratio was 0.306:0.499. From the above results, it was concluded that carteolol is distributed from the circulation to the brain with low penetrability. Received: 30 October 1996/Final version: 16 December 1996  相似文献   
55.
1. To examine whether cytosolic Ca2+ in smooth muscle cells distributes evenly, cytosolic Ca2+ levels were measured with two different Ca2+ indicators in the ferret isolated portal vein; a fluorescent indicator, fura-PE3, that shows the average Ca2+ level, and a photoprotein, aequorin, that preferentially shows a high Ca2+ compartment. 2. A noradrenaline (10 microM)-induced sustained contraction was associated with a sustained increase in the fura-PE3 signal, or a transient increase followed by small sustained increase in the aequorin signal. A high K(+)-induced contraction was associated with a sustained increase in both the fura-PE3 and aequorin signals. 3. A second application of noradrenaline or high K+ induced reproducible contractions and fura-PE3 signals. In contrast, the aequorin signal resulting from a second application of noradrenaline or high K+ was much smaller than the first signal. 4. Following a 13 h but not a 3 h resting period, the aequorin signal stimulated by noradrenaline or high K+ recovered, without any change in the contractile response. 5. In Ca(2+)-free solution, high K+ was ineffective, whereas noradrenaline induced only a small aequorin signal and contraction compared to those obtained in the presence of external Ca2+. After the addition of Ca2+, the first application of noradrenaline induced a large aequorin signal and a large contraction, although a second application induced a much smaller aequorin signal accompanied by a large contraction. 6. These results suggest that high K+ and noradrenaline increase Ca2+ in at least two cytosolic compartments; a compartment that is coupled to the contractile mechanism ('contractile' Ca2+ compartment; major portion of cytoplasm containing contractile elements) and a compartment that is not coupled to contractile mechanisms ('non-contractile' Ca2+ compartment; small sub-membrane area that does not contain contractile elements). On stimulation, the Ca2+ level in the 'contractile' compartment may increase to a level high enough to stimulate myosin light chain kinase but not so high as to consume aequorin rapidly. In contrast, the Ca2+ level in the 'non-contractile' compartment may increase so greatly that aequorin in this compartment is rapidly consumed. These two compartments may be separated by a diffusion barrier and, during a resting period, aequorin may slowly diffuse from the 'contractile' compartment to the 'non-contractile' compartment and thus restore the full aequorin signal. An increase in Ca2+ in the 'non-contractile' compartment seems to be dependent mainly on Ca2+ influx and partly on Ca2+ release.  相似文献   
56.
Epidural spinal cord stimulation was carried out in 4 patients with denervation caused by spinal cord lesion, and we reviewed previously reported cases. Initial result showed at 1 week in 100% of our cases, but about 1/3 of the cases, even those with the same denervation caused by spinal cord lesion, had no pain relief at this stage in previously reported cases. In our cases, excellent pain relief was gained temporarily, even though the painful area and the spinal cord lesion were separated somatotopically in 2 cases (case 3, 4). Temporary success bore no relationship to quality and duration of pain. In all cases except case 1, a rapidly decreasing effectiveness was noted, and finally no pain relief was gained at all after 4, 3 and 5 months, respectively. In case 1 there was persistent pain relief estimated at 70-80% after 19 months, only when the spinal cord was stimulated. Epidural stimulation also produced sensations in the painful area. Spinal cord stimulation would suppress at least the dorsal horn neurons which were destroyed by various kinds of diseases. A decline in effectiveness with time would occur due to essential causes of the deafferentation pain, such as anatomical and regeneration factors.  相似文献   
57.
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   
58.
M Abe  K Tasaki  K Tominaga  S Fukuhara  S Imai  T Osato  H Wakasa 《Cancer》1992,69(3):763-771
Two human Burkitt's lymphoma cell lines (HBL-4 and HBL-5) were established individually from two patients with small noncleaved cell lymphoma (Burkitt's type). The HBL-4 cell line is Epstein-Barr virus (EBV)-negative, and the HBL-5 cell line is EBV-positive. Cytogenetically, both cell lines had the same chromosomal translocation, t(8;14)(q24;q32) as those observed in the primary malignant cells from individual patients. Morphologic, immunophenotypic, cytogenetic, and molecular studies confirmed that both cell lines were derived from the primary lymphoma cells in vivo. HBL-4 cells lacked CD23(H107), CD11a(LFA-1), and latent membrane protein (LMP) but expressed CD54(ICAM-1) at low levels, whereas HBL-5 cells showed the high level of expression of CD54 and faint expression of LMP but lacked CD11a. In addition, the EBV-positive lymphoblastoid cell line (LCL) expressed CD11a, CD23, CD54, and LMP at high levels. Therefore, an HBL-5 phenotype with expression of CD54 and LMP tends toward an LCL phenotype, and the augmentation of CD54 on the HBL-5 cells in comparison with primary lymphoma cells is likely to be upregulated by LMP, probably resulting from the EBV infection. There was little difference in the BrdUrd uptake in vivo and in vitro, doubling time, tumorigenicity, and dynamics of tumor growth in athymic nude mice between both cell lines. These findings indicate that the potentiality of cell growth and tumorigenicity of these two cell lines are unlikely to be related with EBV.  相似文献   
59.
Aortic arch replacement with proximal first technique.   总被引:2,自引:0,他引:2  
BACKGROUND: Deep hypothermic circulatory arrest (DHCA) without retrograde cerebral perfusion (RCP) has a strict time limit. We modified a surgical technique for anastomosis to shorten the period of DHCA and unilateral cerebral perfusion (UCP). METHODS: Between March 1993 and August 2001, retrospective analysis was done on 23 consecutive patients, who underwent aortic arch replacement with branches. The patients were divided into two groups: DHCA group and UCP group. The DHCA group, in which DHCA alone and without additional cerebral perfusion was performed, comprised of nine patients. Proximal aortic anastomosis was performed first during systemic cooling; then both the brachiocephalic artery and left carotid artery were reconstructed with the branches of the artificial graft during circulatory arrest; thereafter, cerebral and coronary perfusions were resumed. The UCP group, in which DHCA was not used but right hemisphere perfusion during deep hypothermia was performed when the origin of brachiocephalic artery was safely clamped, consisted of 14 patients. RESULTS: Mean time of DHCA was 18.8+/-4.2 minutes and that of right hemisphere perfusion time was 11.0+/-3.8 minutes, respectively. Twenty-one patients survived the surgery (91.3%), and two (8.7%) died during hospitalization. Transient cerebral complication occurred in four patients in the DHCA group and all recovered. Logistic regression analysis revealed that DHCA was the only parameter to significantly influence temporary neurological dysfunction. There was no other significant difference between the two groups. CONCLUSION: With our modified and simple surgical technique for aortic arch repair, we were able to successfully shorten the DHCA time and right hemisphere perfusion time. However, because DHCA was the only parameter to significantly influence temporary neurological dysfunction, some form of continuous cerebral perfusion at deep hypothermia may be a safer method to preserve cerebral function.  相似文献   
60.
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   
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