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101.
Seiitsu Ono Takashi Imai Shigeru Munakata Keiichi Takahashi Fumio Kanda Kazuki Hashimoto Takahiko Yamano Natsue Shimizu Koichi Nagao Mitsuo Yamauchi 《Journal of the neurological sciences》1998,160(2):565-147
During the last 10 years, we have demonstrated morphological and biochemical abnormalities of skin extracellular matrices in amyotrophic lateral sclerosis (ALS). However, currently little is known concerning collagen of the spinal cord in ALS. We measured the amount of collagen and characterized collagen at light and electron microscopic levels in posterior funiculus, posterior half of lateral funiculus and anterior horn of cervical enlargement of the spinal cord obtained from ten patients with ALS, 11 patients with other neurologic diseases (control group A), and ten patients without neurologic ones (control group B). In posterior half of lateral funiculus and anterior horn, (1) by light microscopy, there was no significant difference in vessel wall area between ALS patients and control groups A and B; (2) ultrastructurally, collagen bundles were more fragmented and widely separated, and the fibrils were randomly oriented in the perivascular space of capillaries in ALS patients, which were not observed in any areas of control groups or in posterior funiculus of ALS patients; and (3) the collagen contents in ALS were significantly lower (P<0.001 and P<0.001, respectively) than those in control groups A and B. Fragmented and widely separated collagen bundles in the interstitial tissue surrounding capillaries and markedly decreased amount of collagen in posterior half of lateral funiculus and in anterior horn of ALS could be related to the degeneration of the upper and lower motor neurons in the spinal cord in ALS, that is, selective neuronal vulnerability in ALS. 相似文献
102.
The morphological development of the brainstem was studied by means of MR imaging. The subjects were 74 cases ranging in age from 4 months to 16 years, and 6 adult cases. The brainstem development was rapid until 4-6 years of age and thereafter it slowed down. That is the brainstem showed exponential growth (w', t', v and u). The relationship between brainstem growth and the cranium size was divided into 4 types as follows: 1) linear increase with development (s/T-O), 2) plateau (w/T-I and v/RTP-LTP), 3) down and up (u/RTM-LTM and z/RTM-LTM) and 4) exponential (t/T-P). In the values of v, z (the size of the brainstem in axial view) and t/T-P (the ratio of the midbrain and the cranium size in sagittal view), there were significant sex differences for cases of 10-16 years old. These values in male subjects were greater than those in female subjects (v, p less than 0.05, z, p less than 0.01, and t/T-P, p less than 0.05). That is the brainstem in male subjects was greater than that in female subjects. 相似文献
103.
104.
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106.
Primary brain stem lesions caused by closed head injuries 总被引:3,自引:0,他引:3
Takuo Hashimoto Norio Nakamura Karl-Eduard Richard Reinhold A. Frowein 《Neurosurgical review》1993,16(4):291-298
Traumatic lesions of the brain stem are of two types: primary, which are considered to be caused at the moment of impact, and secondary, associated with supratentorial mass lesion. Of the 239 patients with a serious head injury who showed a severe disturbance of consciousness upon admisision and who had CT scan carried out immediately, 21 cases were considered to have a primary brain stem lesion with initial CT scan. A primary brain stem lesion was found in 21 of 239 (8.8%) of patients with serious head injury. Their injuries were caused primarily by traffic accidents. Sixteen of the 21 cases showed not only brain stem lesions but also other brain injuries such as cerebral contusion of the white and gray matter, callosal injury, intraventricular hemorrhage, and subarachnoid hemorrhage, which are considered to be caused by a diffuse shearing injury. Five cases who showed a single injury to the brain stem with no other brain lesions were considered to have a pure brain stem lesion. Primary brain stem lesions were observed on the dorsal side of the midbrain, where they can be differentiated from secondary brain stem lesions. These lesions are considered to result from the shearing mechanism in and around the brain stem very close to the tentorial edge, or to an injury of the lower brain stem by hyperextension of the cervical vertebrae. The prognosis of patients with a primary brain stem lesion was usually unfavorable, except in those with a single brain stem lesion. 相似文献
107.
Percutaneous transluminal angioplasty (PTA) of the vertebral artery was performed with an autoperfusion balloon catheter in five patients. There were no complications in the form of embolic episodes or neurological deficits due to brain ischaemia during inflation. In critical cases with insufficient collateral circulation during temporary occlusion, the use of an autoperfusion balloon catheter may expand the indications for PTA in patients with ischaemic cerebrovascular disease. 相似文献
108.
Effects of isoflurane on oxygenation during one-lung ventilation in pulmonary emphysema patients 总被引:1,自引:0,他引:1
D. Satoh M. Sato A. Kaise Y. Hagiwara T. Saishu Y. Hashimoto 《Acta anaesthesiologica Scandinavica》1998,42(10):1145-1148
Background: Hypoxic pulmonary vasoconstriction has an important role in human one-lung ventilation (OLV) in the lateral decubitus position under general anesthesia. During OLV, inhalational anesthesia may inhibit hypoxic pulmonary vasoconstriction and the decrease in arterial oxygenation. We studied the effect of isoflurane administration on arterial oxygen tension in chronic obstructive pulmonary disease patients.
Methods: Ten patients who had thoracoscopic laser ablation of bullous emphysema were studied. Patients received 2% isoflurane in oxygen from induction until the first 20 min of OLV in the lateral decubitus position, then were switched to 1% isoflurane lasting 20 min and next were switched to 0.5% isoflurane lasting 20 min. After each 20-min inhalation, pulmonary and hemodynamic parameters were measured. The given concentrations for isoflurane were merely vapor meter concentrations.
Results: PaO2 /FIO2 , Qs/Qt respiratory rate peak inspiratory pressure and PaCO2 showed no significant changes at each point of isoflurane. Expiratory tidal volume significantly decreased (P<0.05) with 0.5% isoflurane compared to that with 2% isoflurane. Cardiac output, mean arterial pressure, mean pulmonary arterial pressure, systemic vascular resistance and pulmonary vascular resistance showed no significant changes at each point of isoflurane.
Conclusions: In patients with pulmonary emphysema, arterial oxygenation is not affected by low isoflurane concentration during OLV in the lateral decubitus position. 相似文献
Methods: Ten patients who had thoracoscopic laser ablation of bullous emphysema were studied. Patients received 2% isoflurane in oxygen from induction until the first 20 min of OLV in the lateral decubitus position, then were switched to 1% isoflurane lasting 20 min and next were switched to 0.5% isoflurane lasting 20 min. After each 20-min inhalation, pulmonary and hemodynamic parameters were measured. The given concentrations for isoflurane were merely vapor meter concentrations.
Results: PaO
Conclusions: In patients with pulmonary emphysema, arterial oxygenation is not affected by low isoflurane concentration during OLV in the lateral decubitus position. 相似文献
109.
Wu K; Urano T; Ihara H; Takada Y; Fujie M; Shikimori M; Hashimoto K; Takada A 《Blood》1995,86(3):1056-1061
The effect of the proteolytic cleavage of plasminogen activator inhibitor type 1 (PAI-1) by human neutrophil elastase (HNE) on fibrinolysis was investigated. HNE cleaved active PAI-1 and produced low molecular weight forms of inactive PAI-1, as previously reported. Latent PAI-1 was resistant to HNE treatment. Vitronectin (VN) partially protected the cleavage. NH2-terminal sequence analysis indicated that the cleavage site was Val355-Ser356 (P4-P3). The effects of PAI-1 cleavage by HNE on clot lysis was studied in a purified system. Clot lysis time without PAI-1 was 20.0 +/- 5.0 minutes and was prolonged to 86.7 +/- 2.9 minutes by 68 nmol/L of PAI-1. It was shortened when HNE (from 0.6 nmol/L to 80 nmol/L) was added and returned to the value obtained without PAI-1 by 80 nmol/L of HNE (20.0 +/- 5.8 minutes). However, in the absence of PAI-1, elastase did not enhance clot lysis at all. Euglobulin clot lysis time was also shortened after HNE treatment. The cleavage and inactivation of PAI-1 by HNE was shown to be a novel pathway to enhance fibrinolysis. 相似文献
110.
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