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981.
We experienced a craniopharyngioma in the third ventricle which was removed totally by a staged operation through the lamina terminalis and then through the foramen of Monro using a transventricular approach. In magnetic resonance imaging, chiasmal thickening with pot-belly expansion and bilobed shape of the mass were found, and postoperative magnetic resonance imaging showed indentation of the chiasm and flattening of the floor of the third ventricle. 相似文献
982.
983.
984.
985.
A simplified, non-invasive method for assessment of the performance of the right heart during supine leg exercise was described, which necessitated no more than a bicycle "ergometer" for leg exercise, a radiocardiograph for recording cardiac index (CI) and a "water" manometer for measuring cubital venous pressure (VP). Because the use of a cardiac catheter was omitted, right atrial pressure (RA), right ventricular diastolic pressure (RVd) or pulmonary arterial pressure (PA) were not measured. In 11 healthy subjects and 25 patients with primarily left-sided valvular disease and hypertension, the observed shift of CI-VP plot with exercise was similar to the published records of exercise-induced shift of CI-RA plot or CI-RVd plot in normal subjects and the same types of heart disease. With levels of load used in this study, a dividing line separating normal from abnormal elevation of VP during supine leg exercise (deltaVP) could be drawn at deltaVP = 35 mm H2O, because (1) none of the healthy subjects had deltaVP in excess of 35 mm H2O and (2) in these types of heart disease, deltaVP in excess of 35 mm H2O was always associated with a "subnormal" increase in CI (deltaCI less than 0.8 lit. min-1. M-2) with exercise, except in a few cases who appeared, clinically, to be in what may be termed "latent heart failure". Factors probably responsible for an impaired pumping ability of the right heart during exercise in left-sided heart disease were discussed, in relation to deltaVP. 相似文献
986.
The circulatory effects of epinephrine, added to local anesthetic, during epidural analgesia were compared between middle-aged (52-65 years) and elderly (75-82 years) patients undergoing transurethral resection of the prostate. We used 10 ml of 1.5% lidocaine with or without 1:200,000 epinephrine. The plasma epinephrine concentration peaked 5-10 min after the injection in the patients who received epinephrine with anesthetic. There was no significant difference in the plasma epinephrine concentration between the two age groups. Epinephrine caused a significant increase in the heart rate and a significant reduction in the diastolic arterial pressure in both age groups. A significant reduction of the systolic arterial pressure, however, occurred only in the middle-aged patients. Neither the plasma concentration of endogenous epinephrine, heart rate nor arterial pressure changed significantly in the patients who received plain lidocaine. We conclude that the increase in the heart rate and decrease in the diastolic arterial pressure induced by epinephrine when added to an analgesic may not be influenced by advancing age. In contrast, the reduction in the systolic arterial pressure caused by epinephrine may become less pronounced with age. 相似文献
987.
Prognostic significance of epithelial-stromal vascular cuffing and microvessel density in squamous cell carcinoma of the uterine cervix. 总被引:4,自引:0,他引:4
T Hirakawa T Kamura T Kaku S Amada K Ariyoshi N Kinukawa H Nakano 《Gynecologic oncology》1999,74(3):369-374
OBJECTIVE: Tumor angiogenesis has been shown to play an important role in tumor growth and metastasis. This study examines the prognostic significance of two histological markers of angiogenesis, i.e., vascular cuffing (VC), a bead-like arrangement of microvessels closely surrounding microscopic tumor nests, and microvessel density (MVD), the number of microvessels in a unit area, in cervical squamous cell carcinoma. METHODS: One hundred twenty-two specimens from surgically resected uteri with cervical squamous cell carcinoma were histologically reviewed and immunostained for CD34. VC was graded into "none," "incomplete," and "complete." The MVD was determined by counting the microvessels with a light microscope within a x200 field area where neovascularization occurred most actively. Stromal inflammation was also split into three grades. The relationship of VC or MVD to clinicopathological prognostic factors such as FIGO stage, cervical stromal invasion, lymph-vascular space invasion, pelvic lymph node metastasis, and parametrial invasion was evaluated using univariate and multivariate analyses. RESULTS: The patients with a complete VC pattern showed a significantly worse prognosis compared to those with a pattern graded as either none or incomplete (P<0.011 and P<0.0001, respectively). The Cox regression analysis revealed the complete VC pattern, together with parametrial invasion, to be an independent prognostic indicator for overall survival. MVD and the grading of stromal inflammation showed no significant relationship with VC or overall survival. CONCLUSIONS: The complete VC pattern may therefore be a useful prognostic indicator in cervical squamous cell carcinoma. 相似文献
988.
Pleckstrin homology (PH) domains, comprised of rather weakly conserved sequences of about 100 amino acid residues, are a protein motif found in many signaling and cytoskeletal proteins. PH domains have been shown to bind to the betagamma subunits of heterotrimeric GTP-binding proteins (Gbetagamma), but the affinity of PH domains for Gbetagamma has not been quantitatively estimated in detail. To characterize the nature of the interaction between PH domains and Gbetagamma its kinetic parameters were analyzed using a BIAcore instrument. All PH domains tested (PH domains of ras-specific guanine nucleotide exchange factor (ras-GRF), phospholipase (PLC) gamma1, and Son of sevenless protein (Sos)) appeared to bind to Gbeta1gamma2 with affinity constants K(D) of 0.108, 0.318, and 0.208 microM, respectively. The binding of PH domains to Gbetagamma was inhibited by preincubation of Gbetagamma with the GDP-bound but not the GTP-bound form of Gialpha. This study showed a high affinity interaction between PH domains and Gbetagamma, and suggests a potential role of PH domains in Gbetagamma-mediated signal transduction in intact cells. 相似文献
989.
Neuroendoscopic approach to tectal tumors: a consecutive series 总被引:1,自引:0,他引:1
Oka K Kin Y Go Y Ueno Y Hirakawa K Tomonaga M Inoue T Yoshioka S 《Journal of neurosurgery》1999,91(6):964-970
OBJECT: The authors report a consecutive series of 10 patients who presented with signs and symptoms caused by tectal tumors. Clinical findings, radiographic features, neuroendoscopic management strategies, and histological findings are reported and discussed. METHODS: Since January 1990, 11 neuroendoscopic procedures were performed in 10 patients who harbored tectal tumors. The patients were followed for an average of 5 years (range 2 months-11 years), and a retrospective study was conducted in which case notes, radiological findings, operative notes, and histopathological findings were assessed. Magnetic resonance (MR) imaging was performed, and the images were used to classify patients into three groups: those with hypertrophy of the tectum in whom isointensity appeared on T1-weighted images (Group 1); those with a tectal tumor occupying the cerebral aqueduct in whom decreased signal intensity appeared on T1-weighted images, as well as no enhancement after gadolinium administration (Group 2); and those with a tectal tumor in whom mixed signal intensity and conspicuous evidence of contrast enhancement appeared on T1-weighted images (Group 3). The results of histological examination were consistent with MR imaging features: in Group 1, glial tissue or gliosis; in Group 2, benign astrocytoma; and in Group 3, malignant astrocytoma. Cerebrospinal fluid diversion was the only surgical treatment that provided relief from obstructive hydrocephalus. One patient in Group 3 underwent radiotherapy and subsequent partial tumor removal under neuroendoscopic guidance. Thereafter, the tumor remained in decline. All patients had normal intellectual status after undergoing surgery in which a neuroendoscope was used. CONCLUSIONS: Neuroendoscopic procedures can provide histological diagnosis, define the tumor-midbrain interrelationship, and be highly effective in treating obstructive hydrocephalus and in removing tectal tumors. This procedure may receive clinical application as a new management strategy for tectal glioma. 相似文献
990.
Hirakawa H Iijima H Gohdo T Imai M Tsukahara S 《American journal of ophthalmology》1999,127(4):436-442
PURPOSE: To determine the progression of defects in the central 10-degree visual field in patients with retinitis pigmentosa and choroideremia by means of univariate linear regression with respect to the mean deviation. METHODS: In a retrospective study, results of automated static perimetry in the central 10-degree visual field were reviewed for patients with retinitis pigmentosa and choroideremia. Univariate linear regression of mean deviation was undertaken for each eye that had field data from at least five tests in addition to the prior static perimetric experience during a period of 3.5 years or more. Data from 30 eyes of 16 patients fulfilled eligibility requirements; the mean number of fields was 5.8 (range, five to 10) and the mean follow-up period was 64 months (range, 42 to 97 months). Eyes were classified as progressive if the regression coefficient was negative and significantly different from zero, with a P value of less than .05. RESULTS: Among 14 patients in whom both eyes were eligible for univariate linear regression analysis, a statistically significant progression was demonstrated in both eyes in four patients, only in one eye in five patients, and in neither eye in five patients. One of two patients, in whom only one eye was eligible for the study, showed significant progression in the eye. Overall, 14 (47%) of 30 eyes showed statistically significant progression with respect to the mean deviation. No eye showed significant improvement. CONCLUSIONS: Automated static perimetry of the central 10-degree visual field measured approximately once or twice a year demonstrated the progressive nature of the disease with the use of univariate linear regression of mean deviation in 47% of eyes with retinitis pigmentosa and choroideremia during the follow-up period of 3.5 years or more. These results may be useful in understanding the clinical course of the diseases and counseling patients. 相似文献