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1.
In order to decrease the perioperative complications by preoperative cisplatin chemotherapy, the preoperative single administration of cisplatin (30 mg/m2) was performed weekly from one to six times in 36 consecutive patients with esophageal cancer classified as higher than Stage II. The survival curve of 17 patients in Stage III was significantly better (P<0.05) than that of patients who had been treated without preoperative cisplatin treatment. In 3 of the 12 patients who had locally invasive cancer, either the main tumors or the metastatic lymph nodes, which had invaded the trachea or the left main bronchus, sufficiently receded, so that a curative esophagectomy became possible; 2 of them have survived over 33 months while 1 died of pneumonia 33 months after surgery. The number of perioperative complications was minimal, and thus, we consider that the postoperative use of cisplatin and fluorouracil is indicated in patients in whom a histological response is noted in the resected specimens.This work was partially supported by Grant No. 02454315 from the Japanese Ministry of Education  相似文献   
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OBJECTIVE: To investigate the in vitro effect of Tripterygium glycosides (TG) on cytokine production by splenocytes in oxazolone (OXZ)‐induced colitis in mice. METHODS: Oxazolone (6 mg in 50% ethanol) was administered to male SJL/J mice intrarectally to induce colitis and the mice were killed 3 days later. Isolated splenocytes were cultured for 24 h in the presence of phorbol myristate acetate and ionomycin. A preparation of Tripterygium glycosides at a concentration of either 0.1 mg/mL or 0.01 mg/mL was added to the culture medium of splenocytes. Production of interferon gamma (IFN‐γ) and interleukin‐4 (IL‐4) in the supernatant were measured by ELISA. RESULTS: Production of IFN‐γ in the normal control group was suppressed by TG at both concentrations (0.01 and 0.1 mg/mL; 1.24 ± 0.13 pg/mL (samples without TG) → 0.97 ± 0.26 pg/mL (0.01 mg/mL TG) → 0.87 ± 0.18 pg/mL (0.1 mg/mL TG); P < 0.02) in a dose dependent manner. In the OXZ‐induced colitis group, the basic level of IFN‐γ was significantly lower than that of the normal control group (1.24 ± 0.13 pg/mL vs 0.65 ± 0.08 pg/mL; P < 0.01); but IL‐4 production was significantly increased in the OXZ‐induced colitis without TG group (7.83 ± 0.69 pg/mL vs 5.65 ± 0.48 pg/mL, P < 0.01). In both groups, TG suppressed IL‐4 production in a dose‐dependent manner (normal control group: 5.65 ± 0.48 pg/mL (samples without TG) → 4.97 ± 0.38 pg/mL (0.01 mg/mL TG) → 3.98 ± 0.32 pg/mL (0.1 mg/mL TG), P < 0.01; OXZ group: 7.83 ± 0.69 pg/mL (samples without TG) → 7.07 ± 0.47 pg/mL (0.01 mg/mL TG) → 6.35 ± 0.48 pg/mL (0.1 mg/mL TG), P < 0.01). CONCLUSION: Oxazalone‐induced IL‐4 overproduction by splenocytes was significantly suppressed by TG in a dose dependent manner and the beneficial effects of TG on ulcerative colitis might be related to the suppression of the Th2 type (e.g. IL‐4) mediated immunological response of splenocytes.  相似文献   
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The aim of this study was to compare cerebral perfusion images and regional cerebral blood flow (rCBF) of SPECT study with the images and regional intensity of relative cerebral blood flow (CBF) images acquired by contrast-enhanced perfusion MR imaging (pMRI) and flow-sensitive alternating inversion recovery (FAIR). Twelve patients with various cerebral diseases were underwent I-123-IMP SPECT, pMRI, and FAIR studies to measure rCBF. A total of 12 regions of interest (ROI) were created over cerebrum and cerebellum to acquire the corresponding rCBF from I-123-IMP study and regional average signal intensity from CBF images of pMRI and FAIR studies. Left-to-right (L/R) and cerebral-to-cerebellar (CCR) ratios were created from the rCBF of I-123-IMP and signal intensity of CBF images of pMRI and FAIR. Image quality of FAIR was the poorest among all; however, CBF images of pMRI and FAIR images show comparatively decreased intensity at the corresponding site of decreased perfusion on I-123-IMP images. Both FAIR and pMRI images showed high intensity along the sinuses, choroid plexus, and large vessels in sulci. No significant correlation was found among all imaging modalities. But L/R ratio of I-123-IMP showed significant correlation with those of pMRI and FAIR, but for CCR, significant correlation was observed only between I-123-IMP and FAIR. Perfusion images of both pMRI and FAIR may produce images comparable to SPECT study. But to calculate absolute CBF more easy-to-apply and accurate algorithms are needed to overcome the artifacts from large vessels. Received: 25 January 2000 Revised: 7 June 2000 Accepted: 8 June 2000  相似文献   
8.
Purpose. We examined whether a new application of the priming principle, i.e., having the priming dose of vecuronium administered before the insertion of the epidural catheter, would hasten the onset of the neuromuscular block induced by the intubating dose of vecuronium. Methods. Forty-five adult female patients scheduled for general anesthesia combined with epidural anesthesia were studied. In group A (n = 15), the priming dose of vecuronium, 0.01 mg·kg−1, was administered before insertion of the epidural catheter. The intubating dose of vecuronium, 0.09 mg·kg−1, was given after the insertion of the epidural catheter. In group B (n = 15), the priming dose of vecuronium, 0.01 mg·kg−1, was given 4 min before the intubating dose of vecuronium, 0.09 mg·kg−1. In the control group (n = 15), no priming dose was given, and only the intubating dose of vecuronium, 0.10 mg·kg−1, was administered. In all three groups, general anesthesia was induced with propofol 2.5 mg·kg−1, and the trachea was intubated when T1/control value (control twitch height in response to train-of-four stimuli) was less than 0.1. Results. In group A, the priming dose was given 16 ± 3 min (mean ± SD) before the administration of the intubating dose. The times to onset of neuromuscular block in groups A and B, and the control group were: 145 ± 30, 184 ± 45, and 219 ± 23 s, respectively (P < 0.05 among the three groups). In all three groups, intubating conditions (graded on a four-point scale) were excellent (P = 0.59). Before the induction of anesthesia, symptoms of paralysis were observed in 5, 4, and 0 patients in groups A and B and the control group, respectively (P < 0.05 between group A or B vs control group). Conclusions. If the priming dose of vecuronium is given after a long priming interval (16 ± 3 min), the time to onset of the neuromuscular block caused by the intubating dose of vecuronium is markedly shorter than when the conventional priming interval of 4 min is employed. Received: March 5, 2001 / Accepted: October 4, 2001  相似文献   
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BACKGROUND AND PURPOSE: Flow-sensitive alternating inversion recovery (FAIR) MR imaging is a technique for depicting cerebral perfusion without contrast enhancement. Our purpose was to determine whether quantification at FAIR imaging can be used to assess regional cerebral blood flow (rCBF) in a manner similar to [iodine 123]-iodoamphetamin ((123)I-IMP) single photon emission CT (SPECT). METHODS: Nine patients with internal carotid or major cerebral arterial stenosis underwent (123)I-IMP SPECT and FAIR imaging (single section, different TIs, 1.5 T) at rest and after acetazolamide (Diamox) stress. FAIR and (123)I-IMP rCBF values were compared and correlated. Receiver operating characteristic analysis was conducted to detect hypoperfused segments on FAIR images. RESULTS: rCBF values of normally perfused segments were 41.53 and 51.91 mL/100 g/min for pre- and post-acetazolamide (123)I-IMP studies, respectively. Corresponding values for pre- and post-acetazolamide FAIR images, respectively, were 46.64 and 59.60 mL/100 g/min with a TI of 1200 milliseconds and 53.23 and 68.17 mL/100 g/min with a TI of 1400 milliseconds. (123)I-IMP and FAIR results were significantly correlated, with both pre- and post-acetazolamide images. Sensitivity (86%) in detecting hypoperfused segments was significantly higher with post-acetazolamide images (TI, 1400 milliseconds), and specificity (82-85%) and accuracy (80-82%) were higher with all pre- and post-acetazolamide images (all TIs). CONCLUSIONS: The significant correlation, high specificity and accuracy in detecting hypoperfused segments, similar increases in flow on both post-acetazolamide images, and absence of the need for contrast enhancement suggest that FAIR imaging, like nuclear medicine study, is complementary to routine MR imaging in the assessment of cerebral perfusion.  相似文献   
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Signal intensity (SI) changes of pancreatic parenchyma were evaluated after intravenous administration of secretin using T2-weighted single-shot spin-echo echo-planar imaging (EPI) to assess this method as a magnetic resonance (MR) test of pancreatic exocrine function. Nine volunteers were studied with serial single-shot EPI of the pancreas for 15 minutes after the injection of secretin or saline. The normal pattern of pancreatic SI change was demonstrated after intravenous injection of secretin, a single peak at 3-4 minutes in the head, body, and tail, followed by a gradual decrease in SI. Saline injection did not induce a significant SI change. There was no statistical difference in the peak contrast ratios (first mean, 1.21-1.25, vs. second mean, 1.18-1.22) and peak times (first mean, 3.2-3.7 minutes, vs. second mean, 3.1-3.6) in a repeat study. By evaluating the pattern of time-response curves obtained from serial T2-weighted EPI after secretin injection, pancreatic exocrine function may be directly assessed at the level of the head, body, and tail.  相似文献   
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