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AIM: To investigate the participation of adenosine receptors in the adenosine 5'-triphosphate (ATP)-induced relaxation in the corpus cavernosum penis (CCP) of rabbits. METHODS: The ATP-induced relaxation was assessed on the noradrenaline precontracted CCP of rabbits in the presence and absence of 8-(3-chlorostyryl)caffeine (CSC); an adenosine A(2A) receptor antagonist; alloxazine and MRS1754; adenosine A(2B) receptor antagonists; and ARL67156, an inhibitor of ecto-nucleoside triphosphate diphosphohydrolases. RESULTS: Adenosine and ATP relaxed the noradrenaline precontracted CCP of rabbits in a concentration-dependent manner. The adenosine- and ATP-induced relaxations were suppressed by alloxazine and MRS1754, but not by 8-(3-chlorostyryl)caffeine. ARL67156 potentiated the ATP-induced relaxation but not the adenosine-induced one. MRS1754 suppressed the ATP-induced relaxation potentiated by ARL67156. CONCLUSIONS: The above results suggest that, in the CCP of rabbits, the adenosine receptor mediating adenosine-induced relaxation is of the A(2B) receptor and the ATP directly causes relaxation through the A(2B) receptor on the CCP.  相似文献   
3.
A 75-year-old man had been admitted to another hospital because of left abdominal pain, and was given a diagnosis of left hydronephrosis and acute pancreatitis. After a JJ stent insertion and medication, he was transferred to our hospital for further examinations. US and EUS revealed a chronic pancreatitis-like pattern and multicystic lesion in the pancreas head and body. At that time enhanced CT findings showed an extrapancreatic low density area to be inflammatory change, extending from the pancreas body to the left crus of the diaphragm and posteriorly the spreading from the left crus of the diaphragm via the left urinary duct into the left iliopsoas muscle, in which MRI revealed partial high intensity. ERCP and MRCP showed focal irregular narrowing of the pancreatic duct of unknown cause, and we decided that an internal pancreatic fistula due to pancreatitis had induced left ureteral obstruction, caused by a protein plug or alcohol. Follow-up 6 months later showed that extrapancreatic spreading of the low density area had markedly regressed without any change in the ureteral obstruction.  相似文献   
4.
Under whole cell patch conditions, 1389-S blocked the INa in guinea-pig ventricular myocytes under steady state conditions (Kdrest = 30 microM, Kdi = 2.4 microM) with a shift of the inactivation curve to the hyperpolarizing direction. Both brief and long conditioning pulses could produce a use-dependent block of 1389-S. These results suggest that 1389-S had a higher affinity to the inactivated than to the rested state under steady state conditions and had a higher affinity to the activated state during train pulses as well as to the inactivated state, making channels unavailable for conduction upon activation.  相似文献   
5.
We encountered a rare case of hypersensitivity pneumonitis associated with bilateral hilar lymphadenopathy (BHL). The patient was a 53-year-old male, who developed dry cough and shortness of breath when using a humidifier since 1982. He was admitted to our hospital for further evaluation in 1987. Chest X-ray films showed BHL and ground glass appearance in the bilateral lung fields. Pulmonary function test indicated disturbance of diffusing capacity. Transbronchial lung biopsy revealed interstitial pneumonitis, and lymph node biopsy by mediastinoscopy showed lymphoid sinus histiocytosis without noncaseating granuloma. Provocation test using the humidifier was positive, and the diagnosis of humidifier lung with BHL was made.  相似文献   
6.
A case-control study was conducted to examine factors relating to discontinuation of domiciliary care for the bedridden elderly in Shinagawa-ku, Tokyo. Cases were bedridden residents aged 65 years and over who had abandoned home care and applied for admission to live in a special nursing home for the aged between April and September in 1990 after being recipients of welfare allowances for disabled elderly. Controls were bedridden residents who continued to be given home care and matched to cases by sex, age and beginning month of the receiving of allowances. Among 50 cases and 94 controls interviewed, we obtained responses from 31 cases (62%) and 60 controls (64%). The main results were as follows: 1. During the home-care period, ADL (activities of daily living) of cases, especially walking ability, deteriorated more severely than in controls. Night delirium also appeared more frequently in cases. 2. The primary caregivers of cases were older than those of controls. Remarkable differences between cases and controls were observed in the family structure, the number of family members and the number of sub-caregivers. Cases tended to live alone or live with a spouse only, and with smaller number of family members and caregivers. 3. Case lived more frequently in houses with small numbers of rooms and without rooms of their own. 4. As regards utilization of domiciliary care services, cases used dispatch of home helpers more frequently and used day services less frequently.  相似文献   
7.
Genetic alteration in carcinoid tumors of the lung.   总被引:1,自引:0,他引:1  
Surgically resected specimens of 13 carcinoid tumors of the lung including nine typical carcinoids and four atypical carcinoids, and eight salivary gland type carcinomas (six mucoepidermoid carcinomas and two adenoid cystic carcinomas) were analyzed regarding p53 expression, loss of heterozygosity (LOH) in chromosome 3p, 9p, and K-ras mutation. The overexpression of p53 was identified in four atypical carcinoid tumors, one mucoepidermoid carcinoma, and one adenoid cystic carcinoma, however, none of typical carcinoids showed p53 immunoreactivity. LOH in 3p14 was demonstrated in three of seven informative cases in all tumors. LOH in 9p was demonstrated in two of five informative cases in all tumors. Two of three cases with LOH at 3p14 had a poor prognosis, one of which also had LOH at 9p. No mutation of the K-ras gene was observed in any of these tumors. These data thus indicate that p53 overexpression might distinguish atypical carcinoid tumors from typical tumors and might therefore be useful as an adjunct modality in the differential diagnosis of pulmonary carcinoid tumors. The presence of LOH at 3p14 or 9p may thus help to identify lung cancer patients with a poor prognosis.  相似文献   
8.
The aim of this study was to examine the pharmacokinetics of clinically applied benzoporphyrin derivative monoacid ring‐A (BPD‐MA; Verteporfin®), a second‐generation photosensitizer, during a trial of photodynamic therapy (PDT) in nine dogs having naturally occurring neoplasms. After injecting BPD‐MA at 0.5 mg/kg intravenously, its mean half‐life (t1/2) was found to be 8.14 ± 5.34 h, mean clearance (Cl) 35.13 ± 9.62 ml/(h kg), the mean value of the volume of distribution (Vc) 0.08 ± 0.01 l/kg and the mean steady state volume of distribution (Vss) 0.38 ± 0.31 l/kg respectively. With the exception of a transitional increase in serum alkaline phosphatase activity, no other clinical abnormalities were observed. The t1/2 in dogs with naturally occurring tumours was longer than that in humans, but similar to that in rats. The values of Cl and Vss in dogs having naturally occurring neoplasms were lower than those in humans. It is suggested that the pharmacokinetics of BPD‐MA in tumour‐bearing dogs would be helpful in determining the protocol of a short drug‐light interval PDT with BPD‐MA that mainly targets the tumour vasculature.  相似文献   
9.
Background The antitumor effects of adoptive immunotherapy in combination with chemoradiotherapy were investigated in patients with oral squamous cell carcinoma. Methods Inductive chemoradiotherapy with peplomycin, 5-fluorouracil and60Co was given to 56 patients [CRI(−)group]. A local injection of adoptive lymphokine-activated killer (LAK) cells (≈2×108 cells) and small doses of interleukin-2(≈3×105 U) and interferon-gamma (≈2×105U) was given to 40 other patients in combination with the chemoradiotherapy [CRI(+) group]. Results Clinically, CR, PR, and LR were observed in 15 (37.5%), 24 (60.0%), and 1 (2.5%) of the patients in the CRI (+) group, respectively; and in 14 (25.0%), 38 (67.9%), and 4 of the patients (7.1%) in the CRI (−) group. The histopathological effects were correlated with the tumor remission rate, with lethal degeneration (grades III and IV), and prominent degeneration (grade IIB) in the tumor cells noted in 20 (50.0%) and 16 (40.0%) of the CRI(+) patients, respectively; and in 21 (37.5%) and 29 (51.8%) of the CRI (−) patients. Immunohistochemically, a prominent decrease of proliferating cell nuclear antigenpositive cells with a reciprocal increase of LeY-positve cells was induced by the chemoradioimmunotherapy. DNA fragmentation was observed in the mutant type p53-negative tumors in the CRI(+) group. Conclusion Adoptive immunotherapy with LAK cells and cytokines in combination with chemoradiotherapy induces advantageous anticancer effects resulting from necrosis and apoptosis.  相似文献   
10.
The authors studied 34 patients with juvenile ischemic cerebrovascular disease over a 15-year period. Of the 34 patients, 23 had intracranial occlusions attributed to cerebral thrombosis or embolism and 11 had occlusions resulting from moyamoya disease. Clinicopathological features were evaluated in the 23 cases with ischemic stroke, but not those with moyamoya disease. The cause of the arterial occlusion remained undetermined in 11 patients and was found to be an embolism based on congenital heart disease in 8, on trauma in 3, and on infection in 1. Cerebral angiography was performed in 21 patients. Of these, 17 had stenoses or occlusions corresponding to their symptoms. CT scans were performed in 10 patients; the lesion in question showed no stenosis or occlusion with cerebral angiography. With regard to prognosis, patients with unknown etiology had good outcomes compared with those with congenital heart disease. With respect to acute infantile hemiplegia, 10 patients had convulsive seizures and 4 had a history of an earlier infection. Angiography and CT scans in patients with congenital heart disease demonstrated arterial occlusive sites in the middle cerebral artery region. Three patients had abscesses after their ischemic lesions.  相似文献   
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