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71.
Technetium-99m labeled diethylenetriaminepentaacetic acid (DTPA)-galactosyl human serum albumin (GSA) has been used for hepatocellular functional evaluation. This study proposed new and simple parameters to overcome the limitations of conventional parameters, and they were applied to the clinical staging of chronic liver dysfunction. The study group consisted of 93 patients including 81 with liver dysfunction and 12 control patients. In addition to the two conventional parameters, namely, receptor index (LHL15 = liver count divided by the sum of liver and heart counts at 15 minutes) and clearance index (HH15 = heart count at 15 minutes divided by the heart count at 3 minutes), 6 new parameters for Tc-99m GSA uptake and clearance were generated. The conventional receptor index of LHL15 showed a large variation depending on the size of region of interest (ROI) over the heart. The LHL15 normalized by the ROI size (nLHL15) showed more stable data and a better separation of mild liver dysfunction. A hyperbolic relationship between the LHL15 and HH 15 changed to a linear relationship by using the nLHL15 index. The combination of the liver to heart average count ratio at 15 minutes (LH 15) and T-half (minute) of the heart count also could differentiate each stage well. In conclusion, the use of the ROI-area normalized nLHL is recommended instead of the conventional LHL15. The indices of LH15 and T-half could be alternatively used as practical parameters for clinical staging in liver function.  相似文献   
72.
Summary The distribution of connectin (titin), nebulin and -actinin in the areas of myotendinous junctions of chicken pectoralis muscles was examined by immunocytochemical methods. Staining with antibodies against connectin (4C9, SM1 and P1200) and nebulin formed doublets flanking nonterminal Z-bands; near the end of muscle fibres singlets were seen within the terminal sarcomere on the side adjacent to the terminal Z-bands. The apical regions of muscle processes, where no myosin filaments are present although actin filaments exist, were reactive with anti-nebulin but not with anti-connection. Antibodies against pectoralis (skeletal muscle type) -actinin stained non terminal Z-bands and that against gizzard (smooth muscle type) the sarcolemma. Terminal Z-bands were unreactive with both of these antibodies. These findings indicate that, although terminal and nonterminal Z-bands differ in their molecular composition, connectin and nebulin filaments appear to link myosin and actin filaments, respectively, to both Z-band types.  相似文献   
73.
To determine the availability and limitations of the detection of ischemic lesions by stress thallium-201 myocardial SPECT as the daily routine procedure, we compared and evaluated the detectability of the quantitative analysis (%uptake and washout rate (WR)) and visual evaluation in 104 patients with effort angina and 17 normal subjects. Visual evaluation combined with WR analysis resulted in significantly higher sensitivity (88.0%) but lower specificity (60.2%) than the other methods. The sensitivity by visual evaluation was quite low in multivessel disease (MVD), and in the regions supplied by mild coronary stenosis or by the left circumflex artery. These were markedly improved by combining visual evaluation and WR analysis, but sensitivity in the MVD group was unsatisfactory even with this analytic method in comparison with the single vessel disease group. One of the causes of low sensitivity in the MVD group might be the "true negative": No induction of the ischemia in the regions of milder stenosis, or the regions supplied by the collateral coronary flow. We therefore conclude that the combination of visual evaluation as a qualitative analysis and WR analysis as a quantitative analysis, is the most useful daily routine procedure as a screening test for detecting ischemia.  相似文献   
74.
The presence of small additional hepatocellular carcinomas (HCCs) undetectable before hepatic resection is a crucial topic for hepatic surgeons. We assessed the incidence of pathologically diagnosed multiple HCCs in 267 patients who underwent hepatic resection for HCC. Ninety-five additional HCC nodules were detected in 72 of the patients (27%). The survival rate of these 72 patients was significant worse than for the 195 with single nodular HCC (p= 0.0013). Twenty-one (22%) were detected before surgery, 29 (31%) during surgery, and 45 (47%) on pathologic examination after surgery. The mean nodule diameters for each group were 2.1, 1.0, and 0.9 cm, respectively (p < 0.0001). None of the 21 nodules detected before surgery was well differentiated, whereas 30 of the 74 nodules in the other two groups were well-differentiated. Although the mean nodule diameter of the well-differentiated HCC group was the smallest, there was no significant difference among the three groups assigned according to tumor differentiation (p= 0.2355). Altogether, 9 of 16 patients with additional nodules detected before surgery (56%) and 49 of 59 with additional nodules detected during or after surgery (88%) had cirrhosis of the liver. The odds ratio for detecting a new HCC nodule during or after surgery in the presence of cirrhosis was 5.444 (p= 0.0087). Improvement in the detection of small additional HCC nodules before and during surgery and meticulous follow-up after surgery are necessary for patients with cirrhosis. For patients without cirrhosis, surgical treatment may be performed according to the results of preoperative imaging studies.  相似文献   
75.
Gender difference of alcohol intake and laboratory data was investigated in 165 Japanese patients with alcoholic liver cirrhosis. Mean age of first drinking and habitual drinking were higher in female. Duration of drinking was shorter in female. Although cumulative alcohol intake was larger in male, mean daily alcohol intake did not differ in both gender. Moreover, daily alcohol intake adjusted to body weight was significantly larger in female. Body mass index, serum levels of total protein, albumin and cholinesterase were significantly decreased in female. Platelet counts on admission did not differ in both gender. However, it was significantly increased in female after one month abstinence. C reactive protein, ammonia and serum levels of total bilirubin were significantly higher in female as compared to male. In conclusion, female alcoholics seems to progress to liver cirrhosis earlier because of high daily alcohol intake adjusted to body weight, poor nutritional condition and inflammation caused by endotoxin.  相似文献   
76.
PURPOSE: The aim of this study was to examine the effect of a specific cyclooxygenase-2 inhibitor, rofecoxib, on rectal polyps in familial adenomatous polyposis patients. EXPERIMENTAL DESIGN: This was a randomized, double-blind, placebo-controlled study of the efficacy and safety of rofecoxib in the rectum. Initially, 21 patients were assigned randomly in a 1:1 ratio to receive either 25 mg rofecoxib once a day or a placebo p.o. for 9 months. Patients underwent endoscopy at the beginning of the study and then every 3 months thereafter. We reviewed the videotapes to measure the number and size of polyps in the same area throughout the study period in each individual patient. RESULTS: The polyp number, measured as the percentage of change from the baseline values, was significantly decreased in the rofecoxib group at 3, 6, and 9 months. At 9 months, the polyp number in the rofecoxib group decreased by 6.8% from the baseline values, whereas that in the placebo group increased by 3.1%. The 9.9% difference between the rofecoxib and placebo groups was statistically significant (P = 0.004). At 9 months, the rofecoxib group showed a significant reduction from the baseline in polyp size as compared with the placebo group (-16.2% versus 1.5%; P < 0.001). There was no statistically significant increase in the incidence of any adverse events in treatment with rofecoxib compared with placebo (P = 0.922). CONCLUSIONS: In this study, once-daily treatment with 25 mg rofecoxib, a cyclooxygenase 2-specific inhibitor, significantly decreased the number and size of rectal polyps in familial adenomatous polyposis patients.  相似文献   
77.
Background We studied the relationship between the augmentative effects of leucovorin (LV) on 5-fluorouracil (5-FU) and the inhibition rate of thymidylate synthase (TS) activity in Colon 26 murine colon carcinoma cells and L1210 murine leukemia cells. Methods In cytotoxic and TS inhibition studies, cells were exposed for 24 hours to varied concentrations of 5-FU alone or in combination with 1 or 10 μmol/L LV. Cytotoxicity was determined by colony forming efficiency or trypan blue dye exclusion, and TS inhibition rate was determined by [6-3H]-5-FdUMP binding assay. A growth inhibition curve was constructed for longer exposures. Results For tumor cell growth inhibition and cytotoxicity, the augmentative effect was observed when the lower 5-FU concentrations (0.1 μg/mL) were used. There was no difference in the effects between the low (1 μmol/L) and high (10 μmol/L) LV doses. Normally, TS enzyme levels rise acutely when cells are exposed to 5-FU. Both cell lines displayed an increase in TS after exposure to 5-FU. This exposure to 5-FU resulted in the maintenance of free enzyme. LV was able to increase the ternary complex and TS inhibition rate with little induction of TS, however, the inhibition rate was not dependent on doses of LV. Conclusions It was concluded that the augmentative effect of LV at a concentration of 0.1 μg/mL 5-FU occurred at the clinically achievable levels of 1 μmol/L of LV, and there was no difference in the effect between the low and high doses. TS was inhibited effectively by 5-FU and the addition of LV, without a marked induction of TS.  相似文献   
78.
79.
Background The purpose of this study was to assess the accuracy of contrast-enhanced magnetic resonance imaging (dynamic MR imaging) in the evaluation of preinvasive and early invasive cancer of the cervix. Methods Twenty-nine women with untreated squamous cell carcinoma of the cervix with either no stromal invasion or early stromal invasion underwent pretreatment MR imaging and dynamic MR imaging within 4 weeks of surgical evaluation. The images were evaluated for tumor detection and compared with results of histologic examination of the surgical specimens. Results The lesions in 17 cases with histologically proven stromal invasion of 4 mm or greater were detected with dynamic MR imaging, whereas lesions in only 8 of these cases were detected with T2 imaging. In 9 cases with stromal invasion between 4.0 mm and 5.0 mm, lesions were represented as early phase focal enhancement on dynamic MR images, but not detected on T2-weighted images. In the 12 cases with less than 4 mm stromal invasion, no lesions were visualized on either T2-weighted images or dynamic MR images, except in 1 case of glandular involvement without stromal invasion that appeared as enhancement on early-phase dynamic MR imaging. Conclusion Dynamic MR imaging detected more lesions of early stromal invasion in pretreatment imaging for cervical cancer than nonenhanced MR imaging.  相似文献   
80.
Paclitaxel and irinotecan are important new anticancer agents. The combination of these two agents has been considered for use against a variety of advanced solid tumors. Since the schedule-dependent effects of this combination may be crucial to its use, we studied the interaction of paclitaxel and SN-38 (the active metabolite of irinotecan) in various schedules in four human cancer cell lines in culture. Cell growth inhibition after 5 days was determined using an MTT assay. The effects of drug combinations at the IC80 level were analyzed by the isobologram method. Simultaneous exposure to paclitaxel and SN-38 for 24 h produced antagonistic (subadditive and protective) effects in the human lung cancer cell line A549, the breast cancer cell line MCF7, and the colon cancer cell line WiDr, and produced additive effects in the ovarian cancer cell line PA1. Sequential exposure to paclitaxel for 24 h followed by SN-38 for 24 h, and the reverse sequence, produced additive effects in all four cell lines. These findings suggest that sequential administration, not simultaneous administration, may be the appropriate schedule for the therapeutic combination of paclitaxel and irinotecan. Continued preclinical and clinical studies should provide further insights and assist in determining the optimal schedule for this combination in clinical use. Received: 25 February 1997 / Accepted: 6 November 1997  相似文献   
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