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61.
A E Flynn D L Coggins R E Austin D D Muehrcke G S Aldea M Goto J W Doucette J I Hoffman 《The Journal of surgical research》1990,49(5):379-384
In order to investigate the relationship between coronary perfusion pressure and blood flow distribution in the left ventricle (LV), we measured myocardial blood flow in small regions using radioactive microspheres in six anesthetized, open-chest dogs. Mean coronary perfusion pressure (CPP) was controlled with a femoral artery to left main coronary artery shunt which included a pressurized, servo-controlled blood reservoir. In each dog, we measured flow in 192 regions of the LV free wall (mean weight per region = 206 +/- 38 mg) at different perfusion pressures. At CPP = 80 mm Hg, blood flow to individual regions varied fourfold (0.30 to 1.18 ml/min/g; relative dispersion (RD) = 21.8 +/- 2.3%). At CPP = 50 mm Hg, flow varied over sevenfold (0.08 to 0.60 ml/min/g; RD = 42.8 +/- 10%; P less than 0.01 vs 80 mm Hg). This relationship between flow variability and CPP was present within individual LV layers as well between layers and is much higher than the error associated with the microsphere technique. We conclude that blood flow to small regions of the LV is markedly nonuniform. This heterogeneity becomes more profound at lower CPP. These findings suggest that (1) global measurements of coronary flow must be interpreted with caution, and (2) even in hearts with normal coronary arteries some regions of the LV are more susceptible to ischemia than others. In addition, these findings may help explain the patchy nature of myocardial damage that occurs following periods of low coronary pressure or inadequate myocardial protection during cardiopulmonary bypass. 相似文献
62.
63.
Human central and peripheral nerve cell tumors were examined in detail using antibodies to calcineurin, glial fibrillary acidic protein (GFAP) and neuron-specific enolase (NSE). Forty-eight formalin-fixed and paraffin-embedded specimens of human neuronal tumors, including 27 medulloblastomas, were examined. Calcineurin-positive cells were found in all peripheral nerve cell tumors and the two gangliogliomas, whereas 20 of the 27 medulloblastomas and one of the two cerebral neuroblastomas did not contain calcineurin-positive cells. Differentiation of cells along the neuronal lines was positively correlated with calcineurin immunoreactivity. NSE-positive cells were found in all of the tumors with the exception of the one cerebral neuroblastoma. NSE immunoreactivity was not invariably consistent with calcineurin immunoreactivity and non-neuronal cells were often positive. Calcineurin-positive cells were all devoid of GFAP, but NSE-positive cells expressed GFAP in some tumors. GFAP-immunoreactive cells were found only in central nerve cell tumors, and not in peripheral tumors. In addition, GFAP-positive cells in some tumors such as retinoblastoma and medulloblastoma morphologically revealed not only neoplastic but also reactive astrocytic features. 相似文献
64.
Minoru Hasegawa Maki Goto Itsuki Oshima Shizufumi Ebihara 《Neuroscience and biobehavioral reviews》1995,18(4):537-540
Circadian rhythms of pineal melatonin release were measured in free-moving pigeons, Japanese quails, and chickens under light-dark cycles followed by constant dim light. Although melatonin levels differed among individual birds, circadian rhythms of melatonin were observed in all of them. Using this technique, we could examine phase shifts of melatonin rhythms and suppression of melatonin release by photic stimulation in pigeons. We could also examine effects of norepinephrine infusion on melatonin release. These results indicate that microdialysis is useful for the study of pineal melatonin rhythms in birds. 相似文献
65.
K. Kawabe K. Goto I. Nishino C. Angelini Y. K. Hayashi 《European journal of neurology》2004,11(10):657-661
Mutations in the dysferlin gene (DYSF) on chromosome 2p13 cause distinct phenotypes of muscular dystrophy: limb-girdle muscular dystrophy type 2B (LGMD2B), Miyoshi myopathy (MM), and distal anterior compartment myopathy, which are known by the term 'dysferlinopathy'. We performed mutation analyses of DYSF in 14 Italian patients from 10 unrelated families with a deficiency of dysferlin protein below 20% of the value in normal controls by immunoblotting analysis. We identified 11 different mutations, including eight missense and three deletion mutations. Nine of them were novel mutations. We also identified a unique 6-bp insertion polymorphism within the coding region of DYSF in 15% of Italian population, which was not observed in East Asian populations. The correlation between clinical phenotype and the gene mutations was unclear, which suggested the role of additional genetic and epigenetic factors in modifying clinical symptoms. 相似文献
66.
67.
Tohru Hashimoto M.D. Hironobu Nakamura Shinichi Hori Kaname Tomoda Katsuyuki Nakanishi Takamichi Murakami Takahiro Kozuka Morito Monden Mitsukazu Gotoh Chikazumi Kuroda Kenichi Wakasa Masami Sakurai 《Cardiovascular and interventional radiology》1995,18(2):82-86
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
68.
We experienced 9 patients with "painful ophthalmoplegia", which included 7 cases of the Tolosa-Hunt syndrome (2 males and 5 females, with ages ranging from 36 to 65 years) and 2 cases of the orbital pseudotumor syndrome (2 females aged 42 and 68). The diagnosis of these syndromes was based upon Hunt's criteria and the presence of the intraorbital mass on the brain CT scan. Main manifestations of both syndromes were periorbital pain and ipsilateral oculomotor nerve palsies. Out of 9 cases, 1 patient with Tolosa-Hunt syndrome and 1 patient with the orbital pseudotumor syndrome had bilateral retro-orbital pain and ophthalmoplegia. Pain preceded the ophthalmoplegia except in one patient with Tolosa-Hunt syndrome. Total paralysis of the extraocular muscles supplied by the oculomotor nerve was noted in all the nine patients, and mydriasis was observed on the affected side in 4 of 7 patients with Tolosa-Hunt syndrome and 2 patients with the orbital pseudotumor syndrome. Neurological involvement was not only the oculomotor nerve but also the other cranial nerves; the optic nerve (in 4 cases with Tolosa-Hunt syndrome and 2 cases with the orbital pseudotumor syndrome), the abducens nerve (in 3 cases with Tolosa-Hunt syndrome and 1 case with the orbital pseudotumor syndrome), and the first division of the trigeminal nerve (in 2 cases with Tolosa-Hunt syndrome). Six patients with Tolosa-Hunt syndrome and 2 patients with the orbital pseudotumor syndrome had palpebral edema. Visual disturbance and palpebral edema were severer in the patients with the orbital pseudotumor syndrome. After corticosteroid hormone was administered, there was diminution of the pain within 2 weeks.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
69.
Y Ozeki K Matsumoto M Goto M Hayashi A Onitsuka M Hirose K Shimokawa 《Nihon Geka Gakkai zasshi》1988,89(3):458-463
A case of renal angiomyolipoma with bone formation is reported. A 61-year-old woman was admitted to our hospital with one month history of fever. About 15 cm in diameter mass was palpated in her right lower abdomen. Plain abdominal roentgenography, ultrasonography and computed tomography showed marked calcification in the cephalic portion of the right kidney, tumors surrounding right kidney and another tumor in the right lower abdomen. All these tumors and the kidney constituted a big mass continuously, and no fatty component was demonstrated. Total excision of the mass including the kidney was performed. The mass was 30 X 24 X 10 cm in size and 3,240 g in weight. Histologically, the tumor was compatible to renal angiomyolipoma. But, radiopaque shadows which looked like calcification were disclosed to be bones, and fatty tissues were not seen so much. Therefore, the name "benign mesenchymoma" was thought to be more acceptable than angiomyolipoma in this case. Preoperative diagnosis of renal angiomyolipoma is the demonstration of fatty densities in the tumor, and the characteristic extrarenal development should also be taken into consideration. Furthermore, the bone formation of angiomyolipoma, which is very rare might be an important finding to angiomyolipoma. 相似文献
70.
It has been reported that the two types of muscarinic receptors, "M1" and "M2", exist in the opossum lower esophageal sphincter. The presence of these muscarinic receptor subtypes had been confirmed with the discovery of the M1 selective antagonist, pirenzepine. But little is known about muscarinic receptor subtypes in gastric smooth muscle. The aim of this study was to identify the muscarinic receptor subtypes on the gastric smooth muscle responsible for the contraction of rat gastric muscle strip. Also, we examined the mechanism of the action of aclatonium napadisilate on rat gastric smooth muscle in vitro. The stimulation of M2 receptor caused the contraction of the gastric smooth muscle. McN-A-343, selective M1 agonist, caused weak contraction of the gastric smooth muscle, and this response was not affected by the selective M1 antagonist, pirenzepine. Aclatonium napadisilate stimulated M2 receptor and caused the gastric smooth muscle contraction. We conclude that the contraction of the gastric smooth muscle is caused by the stimulation of the M2 receptor and this reaction was not affected by tetrodotoxin, suggesting the M2 receptor is located directly on the gastric smooth muscle. The weak contraction of the gastric smooth muscle caused by McN-A-343 was not affected by the selective M1 antagonist, pirenzepine, suggesting that McN-A-343 may not be a pure M1 selective agonist. The action of aclatonium napadisilate is supposed to stimulate the M2 receptor. 相似文献