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51.
K Okajima  M Nakata  S Yano  Y Nagata  I Kimura  Y Nakano  M Abe 《Radiology》1991,181(1):273-276
An objective and quantitative method for the evaluation of the quality of megavoltage portal images was developed by applying receiver operating characteristic analysis. On the basis of therapeutic use of portal images, setup errors were employed as "signals" in this experimental study that compared the original portal films with digitized images. Six readers observed 104 portal images of a chest phantom, half of which were "abnormal" (ie, had setup errors). Digital images (2,048 x 2,048 matrix) were enhanced by means of histogram equalization and then printed with a laser printer for observation. The readers showed a higher discrimination capacity with the digitally enhanced images, although a statistically significant improvement was not demonstrated. The present method of assessment of image quality proved to be both simple and clinically reasonable.  相似文献   
52.
The nerve distribution to the knee joints was analyzed in 5 cadavers and 10 joint capsules specimens were resected during total knee arthroplasty. We found nerve fibers immunoreactive for anti-substance P antibody in the articular capsule. By confocal laser scanning microscopy, we evaluated the three-dimensional structures of the Ruffini's corpuscles and the free nerve endings, both of which were immunoreactive for anti-protein gene product 9.5.  相似文献   
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Assays were made for paralytic toxicity of marine invertebrates inhabiting at the coasts of Hiroshima Bay, where the infestation of bivalves such as cultured oysters with paralytic shellfish poison (PSP) has been occurred. The starfish Asterina pectinifera collected at the estuary of Nikoh River, Hiroshima Bay, was found to contain moderate levels of paralytic toxicity. Its highest toxicities as PSP found on July 30, 1999 were 12.5 MU/g for whole body, 11.0 MU/g for integument tissues and 3.9 MU/g for viscera, respectively. The toxicity of integument was changed from 3.6 to 11.0 MU/g in 1 year. Its paralytic toxin principles were identified as PSP toxins, composing mainly from saxitoxin (STX) group toxins such as carbamoyl-N-hydroxy neosaxitoxin (hyneoSTX), and STX, by HPLC and LC-MS, accounting for over 90 mol%. The PSP toxins contained in the starfish A. pectinifera considered to be transferred from bivalves or detritus living in the same area, which were contaminated with PSP. However, the involved pathway may be different from that of Asterias amurensis which was infested directly through food chain from its food bivalves, for its toxin pattern.  相似文献   
55.
Thrombolysis with conventional thrombolytic agents prior to percutaneous coronary intervention (PCI) has had no impact on the treatment of acute myocardial infarction (AMI). However, the development of mutant tissue type plasminogen activators (mt-PA) has prompted us to reassess the combination of thrombolysis and PCI. Monteplase is a newly developed mt-PA that can be administered as a single intravenous bolus injection. The results of the COMA (COmbining Monteplase with Angioplasty) trial, suggest that monteplase administration prior to emergent PCI in AMI improves 6-month outcomes and possibly the long-term prognosis of myocardial infarction. Combining monteplase administration on presentation at a community hospital with prompt transfer to a tertiary center for PCI would be an ideal strategy for the treatment of AMI.  相似文献   
56.
PURPOSE: We investigated on a problem of long-term follow up in patients with renal cell carcinoma. PATIENTS AND METHODS: A total of 287 patients with renal cell carcinoma treated in Nara Medical University and affiliated facilities from January 1980 to December 1990 were examined. And we investigated the trend of explanation to patients including 287 patients from 1991 to 1995. RESULTS: Up to December 1995, there are 76 patients (26.5%) unable to be followed and 211 patients able to be followed. The former group patients were less declared cancer rather than the latter group patients. Of 76, 22 patients (28.9%) might misunderstand completely recovering from the cancer disease. For the recent 5 years, those patients who were declared cancer increased, and those patients who were explained benign disease decreased. CONCLUSION: These results suggested that declaration of cancer is important for patients with renal cell carcinoma to be followed for a long-term.  相似文献   
57.
BACKGROUND: Thyrotropin-releasing hormone (TRH) is now used as a therapeutic agent for various neurological disorders. Animal study has shown that TRH was attributable to increased cerebral blood flow (CBF). AIMS: There have been occasional reports that TRH therapy was effective for improving symptoms of persistent disturbance of consciousness after acute encephalitis or encephalopathy during childhood. To determine whether TRH has an effect on increasing CBF to patients who have consciousness disturbance caused by acute encephalitis or encephalopathy, and to determine the optimal method of administration. METHODS: Sixteen patients aged 0.7-10.9 years (mean age, 3.2+/-3.1 years) who presented with persistent disturbance of consciousness resulting from acute encephalitis or encephalopathy and were treated with TRH. Regional CBF (rCBF) was measured by single photon emission computed tomography before and after TRH therapy. The alteration rates of rCBF were compared between the divided two groups concerning the dose levels, dosing periods, and treatment lags. RESULTS: The alteration rates of rCBF of the high dose group were higher than those of the low dose group. Differences in the dosing periods and treatment lags did not cause any significant difference of the alteration rates of rCBF. CONCLUSION: The study showed that higher alteration rates of the CBF were observed in the higher dosing group, and TRH have the potency of increasing CBF. TRH therapy would have the potential for effective treatment of persistent consciousness disturbance caused by childhood acute encephalitis or encephalopathy.  相似文献   
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Purpose. To demonstrate the utilities of a synthetic low-affinity ligand ((Gal)3) for the asialoglycoprotein receptor (ASGP-R) as a hepatic targeting device for therapeutic cytokines. Methods. The site-specific incorporation of (Gal)3 or a typical high-affinity ligand (GalNAc)3 into IL-2 was catalyzed by microbial transglutaminase. The anti-tumor activities, pharmacokinetic profiles and receptor-mediated endocytosis in hepatocytes of the ligand-IL-2 conjugates were examined in mouse. Results. The (Gal)3 has approximately 50 times lower affinity to ASGP-R than (GalNAc)3. Nevertheless, the antitumor effects were in the order of (Gal)3—IL-2 > unmodified IL-2 > (GalNAc)3—IL-2. The systemic elimination and the hepatic uptake of (GalNAc)3—IL-2 were more rapid than (Gal)3—IL-2. The ratio of the rate constant representing dissociation from the cell-surface receptor (koff) to that representing endocytosis of the ligand (kint) was greater for (Gal)3—IL-2 than (GalNAc)3—IL-2, suggesting that (Gal)3—IL-2 preferably avoids internalization due to its lower affinity to the receptor. The simulation studies demonstrated that (Gal)3—IL-2 was present in the hepatic extracellular space for a longer period than (GalNAc)3 IL-2. Conclusions. The (Gal)3 ligand increases the therapeutic efficacy of IL-2 by enhancing its exposure to the cell-surface. The koff/kint affects the targeting efficacy of the conjugates to ASGP-R.  相似文献   
60.
A 39-year-old woman was hospitalized for nephrotic syndrome. Laboratory test results showed increased serum creatinine levels and urinary excretions of beta-2-microglobulin, and N-acetyl-beta-D-glucosaminidase. A renal biopsy revealed collapsing focal segmental glomerulosclerosis (FSGS) and acute interstitial nephritis. Despite treatment with pulse steroid followed by oral high-dose glucocorticoids and cyclosporines, heavy proteinuria persisted. After low-density lipoprotein apheresis (LDL-A) therapy was initiated, her proteinuria gradually decreased, leading to complete remission. A repeat renal biopsy after treatment revealed no collapsing glomeruli. Immediate LDL-A should be performed to treat cases of collapsing FSGS poorly responding to other treatments.  相似文献   
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