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81.
Effect of clot removal on cerebral vasospasm 总被引:3,自引:0,他引:3
The effect of clot removal on cerebral vasospasm was studied in 104 patients with aneurysmal subarachnoid hemorrhage (SAH). The series included patients who fulfilled all of the following criteria: operation was performed by Day 3 after the ictus; the patient's preoperative clinical grade was between Grades I and IV; there was no rebleeding; computerized tomography (CT) showed only SAH; and carotid angiograms were performed by Day 2 and repeated between Days 7 and 9. Both the degree of SAH on CT and angiographic vasospasm were graded from 0 to III. The relationship of the SAH grade in the basal frontal interhemispheric fissure (IHF) to the presence of vasospasm at the A2 segments of the anterior cerebral artery and the relationship of the SAH grade in the sylvian stems to the presence of vasospasm at the M1 segments of the middle cerebral artery were analyzed. Correlation of preoperative and postoperative SAH grades with the angiographic vasospasm grades, with the incidence of symptomatic vasospasm, and with the low-density area on CT could be found in the A2 and M1 territories. Decrease of cisternal blood measured by CT after the operation did not relate directly to the reduction of vasospasm. When the SAH was Grade II or III in the basal frontal IHF, the angiographic vasospasm grades at the A2 were significantly lower in patients with surgery via the interhemispheric approach than in those with surgery via the pterional approach. Symptomatic vasospasm occurred in two of the eight cases operated on by the interhemispheric approach compared with 11 of the 22 cases approached via the pterional route. In patients with a pterional approach, there was no significant difference in severity of vasospasm in the M1 territory between the side of approach and the opposite side. No consistent relationship could be found between the time interval from SAH to operation and the severity of vasospasm. While clot removal may ameliorate cerebral vasospasm, its effect per se does not seem to be significant. 相似文献
82.
Takashi Ito Ryuji Sakakibara MD Tatsuya Yamamoto Tomoyuki Uchiyama Zhi Liu Masato Asahina Morihiro Higashi Kimihito Arai Shoichi Ito Yusuke Awa Kaori Yamamoto Mika Kinou Tomonori Yamanishi Takamichi Hattori 《Clinical autonomic research》2006,16(1):66-71
Abstract Uro-neurological assessment was performed in four patients with small-fiber neuropathy due to amyloidosis (2 transthyretin-type/2
immunoglobulin light-chain-type). Voiding difficulties were due to detrusor weakness and impaired bladder sensation. In two
patients cholinesterase inhibition treatment caused urge incontinence, indicating detrusor denervation supersensitivity. The
underlying mechanisms of urinary dysfunction seem to involve postganglionic cholinergic and afferent somatic nerves. 相似文献
83.
Ken Yamaguchi Katsumi Aoyagi Ken-ichi Urakami Toyoharu Fukutani Noboru Maki Shigehiro Yamamoto Kotomi Otsubo Yoshio Miyake Tetsuro Kodama 《Cancer science》1995,86(7):698-705
Our previous study demonstrated that pro-gastrin-releasing peptide(31–98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients. 相似文献
84.
85.
Summary Using xenon-enhanced computed tomography for the study of cerebral blood flow, simultaneous measurements of end-tidal and arterial blood xenon concentrations using the blood collection method were performed to investigate the validity of substituting the end-tidal for the arterial blood xenon concentration. Simultaneous measurement by both methods was performed 68 times in 27 patients. There was no statistical correlation between the arterial blood accumulation rate constant obtained by arterial blood and end-tidal samples, nor between the arterial blood saturation value obtained by the two methods, even when correction was made for age. In brain tissue, all parameters calculated using the end-tidal concentration were lower than those using arterial blood. We therefore suggest that cerebral blood flow values calculated using end-tidal xenon concentration are useful only for qualitative cerebral blood flow mapping, and not applicable to absolute values of cerebral blood flow. 相似文献
86.
87.
H Kimura Y Yamaguchi M Fujino N Yamamoto 《[Zasshi] [Journal]. Nihon Kyōbu Geka Gakkai》1992,40(8):1177-1181
Lymph node metastasis was analyzed quantitatively with 4 categories and relation to post surgical survival and recurrence pattern was studied in patients with pN2 primary lung cancer who underwent relatively curative or relatively noncurative resection of the tumors. There was no relation between metastatic coefficient and post surgical survival, however, better survival was observed when the metastatic ratio and metastatic frequency were low and metastatic mode was random or skip pattern rather than sequential pattern. Metastatic coefficient and metastatic frequency were higher in cases with recurrence in lymph nodes but the former was lower and the latter was higher in cases with recurrence in intra-pulmonary dissemination or metastasis. There was no relation between metastatic coefficient and distant metastasis but metastatic frequency was lower in cases with recurrence in distant metastasis. Cases with sequential lymph node metastasis showed a tendency of lymph node recurrence and intrapulmonary metastasis and those with random or skip metastasis of lymph nodes had a tendency of distant metastasis. 相似文献
88.
Peritumoral brain edema associated with meningioma--histological study of the tumor margin and surrounding brain. 总被引:2,自引:0,他引:2
Thirty-nine cases of intracranial meningiomas were analyzed to identify factors causing brain edema. Edema was significantly correlated with tumor size and the destruction of the leptomeninges and cortex. Meningotheliomatous meningioma tended to have more peritumoral edema. There was no correlation between the presence of edema and location of the tumor or histological features including lymphocytic infiltration and the presence of glial fibrillary acidic protein-positive cells in the tumor tissue. Larger tumors destroy the leptomeninges and cerebral cortex, allowing direct transmission of humoral edema-promoting factor or edema fluid into the white matter, resulting in vasogenic edema. 相似文献
89.
Mechanisms of long-lasting effects of benidipine on Ca current in guinea-pig ventricular cells. 总被引:2,自引:0,他引:2
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1. Benidipine (KW-3049), a new derivative of 1,4-dihydropyridine (DHP), showed dose-dependent inhibition of Ca current (ICa) which was elicited by depolarization from -40 mV to +10 mV at 0.2 Hz in single cardiac cells isolated from guinea-pig ventricle under whole cell voltage clamp. Half inhibition doses (IC50) of benidipine and nifedipine for the peak ICa at +10 mV were 2.7 nM and 63.1 nM, respectively. 2. A change in holding potential from -40 to -75 mV partially removed the block induced by both 10 nM benidipine and 100 nM nifedipine. The block of ICa by benidipine strongly depended upon holding potentials as did that induced by nifedipine. 3. The effect of 100 nM nifedipine was mostly removed when the cells were kept quiescent at holding potentials negative to -75 mV for 5 min after withdrawal of nifedipine. In contrast, hyperpolarization for several minutes did not significantly accelerate the removal of benidipine-induced block after withdrawal of the drug. Effects of 10 nM benidipine could not be washed out for up to 30 min regardless of the holding potentials. 4. It is suggested that the dissociation of benidipine from the DHP binding site, like that of nifedipine, is greatly accelerated by hyperpolarization. Benidipine but not nifedipine may have an additional interaction with the channel or lipid membrane and cannot be washed away even after the dissociation. Alternatively, the dissociation of benidipine from the DHP binding site may be too slow to occur substantially during the limited period of hyperpolarization in the present study (less than 30 min).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
90.