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21.
A technique for reducing the morbidity and mortality of pancreatoduodenectomy by using an omental flap to protect the anastomoses and splanchnic vessels exposed during dissection is described herein.  相似文献   
22.
Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT.  相似文献   
23.
A 61-year-old man had been treated for malignant fibrous histiocytoma with the pulmonary and the lymph node metastasis in the department of orthopedics in our hospital. He was admitted to our department because of an acute onset of conscious disturbance and non-fluent aphasia. Diffusion-weighted imaging (DWI) showed high signal intensity areas in the bilateral cerebella, thalami and posterior lobes. T2WI did not show any mass effects. Enhanced CT did not reveal any enhanced lesion. He was diagnosed as having cerebral embolism, and his conscious disturbance was improved after medication. Eight weeks later, he presented dysphagia, dysarthria, and ataxia in his extremities. DWI showed multiple lesions of low signal intensity located at the identical place where had showed high signal intensity in the initial DWI. T2WI showed high signal intensity area with mass effect. It was indicated that cerebral metastasis might grow after tumorgenic embolism. This is a rare case that tumor emboluses were developed to the metastatic brain tumors.  相似文献   
24.
1. Sensory mechanisms play an important role in the vagal regulation of tracheobronchial smooth muscle tone. We examined the effect of KW-4679, an anti-allergic drug, on guinea-pig tachykinin-mediated contractile responses induced by electrical field stimulation (EFS) in guinea-pig bronchial muscles. 2. EFS (8 Hz, 0.5 ms, 15 V, for 15 s) evoked biphasic contractile responses in the guinea-pig isolated main bronchus in the presence of 5 microM indomethacin. The contractions consisted of a fast phase of an atropine-sensitive transient contraction and a slow phase of a sustained contraction which was inhibited by a combination of the tachykinin NK1 receptor antagonist, (+/-)-CP-96,345 (1 microM) and the NK2 receptor antagonist, SR 48969 (0.1 microM). 3. KW-4679 preferentially inhibited the slow phase in a concentration-dependent manner by 43.2 +/- 7.7% at 10 microM, whereas the drug had no effect on the fast phase at concentrations up to 10 microM. KW-4679, at a concentration of 100 microM, inhibited not only the slow phase by 49.2 +/- 11.4%, but also the fast phase by 36.8 +/- 9.3% [corrected]. 4. KW-4679 (10 microM and 100 microM) did not affect the substance P-induced or neurokinin A-induced contraction. Against the acetylcholine-induced contractile responses, 100 microM KW-4679 had a marked effect producing a 10.2 fold shift to the right in the curve. 5. The inhibitory effect of KW-4679 (10 microM) on the slow phase contraction was not influenced by treatment with naloxone (100 nM), propranolol (1 microM), thioperamide (1 microM), saclofen (50 microM), yohimbine (1 microM), methiothepin (1 microM) or methysergide (1 microM). 6. The inhibitory effect of KW-4679 (10 microM) on the slow phase contraction was not influenced by treatment with intermediate or large conductance Ca(2+)-activated K+ channel blockers (charybdotoxin (10 nM) or iberiotoxin (10 nM)), but suppressed by treatment with small conductance Ca(2+)-activated K+ channel blockers, apamin (500 nM) or scyllatoxin (300 nM). Apamin or scyllatoxin per se did not influence the slow phase contractions. 7. The results suggest that KW-4679 preferentially inhibits the release of tachykinins from the bronchial sensory nerves through activation of small conductance Ca(2+)-activated K+ channels.  相似文献   
25.
26.
OBJECTIVE: Severe aortic arch obstruction including an interrupted aortic arch in congenital complex heart anomalies remains a challenge in surgical management. METHODS: Treatment and outcomes in 75 consecutive patients who underwent an aortic arch repair as the first step of the staged repair protocol between 1975 and 2000 were reviewed. Their ages at repair ranged from 1 day to 8.5 months. RESULTS: Cross-sectional postoperative follow-up data were available in all the patients. The follow-up period ranged from 0 to 27.6 years (mean: 7.3 +/- 7.3 years). There were 20 postoperative hospital deaths (27%) and 7 late deaths. The Kaplan-Meier estimate of survival was 81.3% +/- 4.5% at 1 month, 68.0% +/- 5.4% at 1 year, 65.0% +/- 5.5% at 5 years, 63.1% +/- 5.7% at 10 years, 63.1% +/- 5.7% at 20 years. By Cox regression analysis, body weight of 2.5 kg or less is the only independent determinant of postoperative mortality (p = 0.04, multivariable odds ratio: 2.50, [95% confidence interval: 1.02-6.1]). The aortic arch morphology, the primary cardiac lesion, or date of operation did not reach a statistically significant level to show correlation with mortality. Reintervention to reconstruct the aortic arch was performed at 9 occasions in 8 of the 55 patients who survived the primary operation (14.5%). The Kaplan-Meier estimate of the reintervention-free rate was 91.3% +/- 4.2% at 5 years, 85.5% +/- 5.6% at 10 years, 75.6% +/- 8.2% at 20 years. Using multivariable Cox regression analysis, interrupted aortic arch (versus aortic coarctation) was the only independent predictor of a shorter time to reintervention (p = 0.001, multivariable odds ratio: 16.1, [95% confidence interval: 3.2-80.2]). CONCLUSIONS: The staged repair protocol was associated with significant limitations in patient survival and with the development of recurrent aortic arch obstruction. Thus, a primary repair protocol may serve as an alternate approach, especially in patients with low weight or with an interrupted aortic arch.  相似文献   
27.
BACKGROUND: Olopatadine hydrochloride (olopatadine; Allelock) is one of the second-generation antihistamines that are treated for allergic disorders such as rhinitis, urticaria and eczema dermatitis. Olopatadine has recently been shown to have inhibitory effects on the chronic contact hypersensitivity induced by repeated application of oxazolone in mice. Although topical steroids have widely been prescribed for atopic dermatitis, a relapse often occurs within several days after discontinuation of their prolonged use. OBJECTIVES: We investigated the possible efficacy of olopatadine against the relapse after discontinuation of prolonged use of topical prednisolone in the Balb/c mice with oxazolone-induced chronic contact hypersensitivity. METHODS: Mice with the chronic contact hypersensitivity induced by repeated application of oxazolone were treated with olopatadine as a sequential therapeutic agent. The effects of olopatadine were quantified by measurements of ear-swelling, and levels of cytokines and histamine in the lesioned ear. Results Topical prednisolone (0.05 mg/ear/day) significantly inhibited the increases in ear swelling and production of IL-1beta, IL-4, IL-18, granulocyte-macrophage colony-stimulating factor (GM-CSF) and histamine. However, after discontinuation of the treatment with topical prednisolone, the inflammation relapsed and the IL-4 level exceeded the control one. The sequential treatment with olopatadine (10 mg/kg/day) after discontinuation of the treatment with topical prednisolone alone, or topical prednisolone with olopatadine, significantly inhibited the increases in ear swelling and levels of IL-1beta, IL-4, IL-18, GM-CSF, nerve growth factor and histamine. CONCLUSIONS: These results indicate that olopatadine is an antihistamine agent having inhibitory activities against the rebound phenomenon following the discontinuation of topical steroid therapy. Olopatadine is thus expected to be a sequential therapeutic agent after discontinuation of the chronic treatment with a topical steroid.  相似文献   
28.
We report here on the ionic mechanisms underlying the depolarizing afterpotential (DAP) in neocortical pyramidal cells, with special interest in those underlying the burst afterdischarge. Injections of short depolarizing current pulses under whole-cell current clamp with a CsCl-based internal medium generated, in most pyramidal cells, a single action potential with a plateau phase (plateau-AP), followed by a slowly decaying DAP both in the absence and presence of TTX. Under voltage-clamp, the same cells displayed a slow tail current (tail-I) at the offset of depolarization. When intracellular free Ca2+ was chelated with 10 mm BAPTA or when extracellular Ca2+ was replaced with equimolar Ba2+, neither the slow DAP nor the slow tail-I was observed. Extracellular application of Co2+ or Cd2+ reduced Ca2+ currents and the slow tail-I. Cation substitution experiments revealed that the channel generating the slow tail-I was permeable to K+ and Cs+ more than to Na+ (PKPCs > PNa > PNMDGPTEA). The cationic slow tail-I was not reduced by applying antagonists of the metabotropic glutamate receptor (MCPG, 1 mm ) and the muscarinic receptor (atropine, 1–10 μm ). Thus, the slow DAP was produced by activation of the cationic channel whose gating is solely dependent on [Ca2+]i. An increase in [K+]o from 3 to 6 or 9 mm enhanced the slow DAP, and resulted in a generation of burst afterdischarges. An anticonvulsant, phenytoin (PT; 1–10 μm ) suppressed the slow DAP while enhancing the plateau-AP in the presence of TTX, most likely by blocking the cationic channel.  相似文献   
29.
30.
Purpose: To evaluate the efficacy of transcatheter oily chemoembolization (TOCE) for hepatoceliular carcinoma (HCC) on the basis of microscopic and macroscopic findings postembolization. Methods: HCCs ranging in size from 0.5 to 13 cm (mean 3.6 cm) were obtained from partial hepatectomies of 100 consecutive patients who had undergone TOCE between 20 and 246 days (mean 59.5 days) prior to surgery. The efficacy of TOCE was assessed on the basis of the necrotic to live cell ratio of the tumors. The microscopic pattern of tumor growth was grouped into expanding type (complete capsule formation) and replacing type (incomplete or no capsule). There were five types of macroscopic groupings: single nodule, single nodule with extranodular growth (SNE), contiguous and noncontiguous multinodular, and massive growth type. Results: Among 79 cases with the expanding type, 29 (37%) had 100% HCC necrosis, but none with 100% necrosis were in the replacing type. By macroscopic grouping, the efficacy of TOCE decreased from the single nodule type (50% of patients had 100% necrosis) to the SNE type (21%), and the other types (9%).  相似文献   
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