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101.
OBJECTIVE: The purpose of our study was to determine the accuracy of MRI for preoperative staging of renal cell carcinoma using the 1997 TNM classification. MATERIALS AND METHODS: We conducted a retrospective review of MRI performed in 40 consecutive patients with 42 renal cell carcinomas before radical (n = 35) or partial (n = 4) nephrectomy or exploratory laparotomy (n = 3). The interval between imaging and surgery ranged from 1 to 59 days (mean, 17.9 days). Imaging was performed with T1- and T2-weighted, dynamic gadolinium-enhanced, and time-of-flight sequences. MRI and surgical-pathologic staging was performed using the 1997 TNM staging system. MRI staging was compared with surgical-pathologic staging as the gold standard. Agreement between the two staging methods was assessed using the kappa statistic. RESULTS: Agreement between MRI and surgical-pathologic staging was good for T staging (kappa = 0.72 and 0.78 for reviewers 1 and 2 respectively), poor for N staging (kappa = 0.13, both reviewers), good for M staging (kappa = 0.66, both reviewers), and excellent for the assessment of venous involvement (kappa = 0.93, both reviewers). MRI overestimated the T stage in five patients and the N stage in five and underestimated the T stage in three, the N stage in four, the M stage in one, and the extent of venous thrombosis in two patients. CONCLUSION: MRI is a reliable method for preoperative staging of renal cell carcinoma using the 1997 TNM classification, in particular for assessing venous involvement.  相似文献   
102.
BACKGROUND: The A3243G mutation of mitochondrial DNA (mtDNA) is involved in many common diseases, including diabetes mellitus and mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS). For detection of this mutation, allele-specific PCR is highly sensitive but requires strict control of PCR conditions; it thus is not adequate for a routine clinical test. We aimed to develop a routinely available PCR method for quantitative detection of low-level heteroplasmy of the A3243G mutation. METHODS: Quantitative allele-specific PCR for the A3243G mutation was performed in the presence of peptide nucleic acid (PNA), in which PNA is complementary to the wild-type mtDNA, with one primer having a 3' end matched to nucleotide position 3243 of the mutant. RESULTS: With our method, amplification of wild-type mtDNA was suppressed 7000-fold compared with amplification of the mutant mtDNA under a broad range of conditions: DNA, 5-100 ng; annealing temperature, 61-66 degrees C; and PNA, 1.5-3.5 micromol/L. Hence, 0.1% heteroplasmy of the A3243G mutation can be reliably quantified by this method. Blood samples form 40 healthy volunteers showed <0.06% heteroplasmy, suggesting that 0.1% is diagnostically significant. CONCLUSIONS: PNA maintains the specificity of allele-specific PCR over a wide range of conditions, which is important for routine clinical testing.  相似文献   
103.
Increased aqueous flare intensity in eyes with liquefied after-cataract   总被引:2,自引:0,他引:2  
PURPOSE: To describe aqueous flare intensity in eyes with white liquefied after-cataract. SETTING: Department of Ophthalmology, Toyama Medical and Pharmaceutical University, Toyama, Japan. METHODS: Seven patients with unilateral liquefied after-cataract and another 10 unaffected patients with an intraocular lens (IOL) were examined. The eyes were divided into 3 groups. The first group was composed of 7 eyes with liquefied after-cataract. The second group included the fellow eyes of the patients with unilateral liquefied after-cataract; 4 had an IOL, and 3 had cataract. The third group included 10 additional eyes without liquefied after-cataract. All patients underwent cataract operations consisting of phacoemulsification/aspiration with continuous curvilinear capsulorhexis and acrylic IOL implantation in the capsular bag. Aqueous flare was measured using a laser flare-cell meter. RESULTS: The mean +/- SD of aqueous flare intensity was significantly higher in the first group (11.8 +/- 1.8 photon counts/msec) than in the second group (6.4 +/- 0.8 photon counts/msec) and in the third group (6.3 +/- 0.7 photon counts/msec). CONCLUSION: It is possible that liquefaction of after-cataract and disruption of the blood-aqueous barrier may be related.  相似文献   
104.
A 41-year-old man was found to have advanced gastric cancer with simultaneous multiple bone metastases when pyloric stenosis was being diagnosed in our hospital. We performed gastrojejunostomy from the lower third of the stomach to the upper third of the duodenum to relieve the obstruction. However, at 8 days after surgery, disseminated intra-vascular coagulation (DIC) occurred. Therefore, the patient was administered combined chemotherapy with TS-1 plus low-dose cisplatin in addition to anti-DIC therapy. TS-1 (150 mg/day) and cisplatin (10 mg/body intravenously over the course of 30 minutes) were administered on days 1 to 5, 8 to 12, and 15 to 19 (weekday-on/weekend-off schedule). There was remarkable response to this chemotherapy, and the patient was shifted from inpatient to outpatient treatment. The treatment course was repeated for 4 cycles until remission was observed. Because of hematologic relapse due to DIC at 6 months after the first treatment, he was readmitted for administration of combined chemotherapy. Fortunately, DIC once again responded to the same chemotherapy regimen. In this pathologic condition, combined chemotherapy is unavoidable when DIC occurs with cancer. Accordingly, it is necessary that an effective combined chemotherapy with mild bone marrow suppression be chosen. A companion drug should be chosen in consideration of delayed homo-toxicity and of the possibility of relapse into DIC in the drug withdrawal period. In addition, it is indispensable that careful consideration be given to the most favorable dose and regimen.  相似文献   
105.
The patient was a 50-year-old female with peritoneal metastasis of Type 4 gastric cancer. She underwent a relative curative resection with total gastrectomy and peritonectomy. Postoperative chemotherapy with 5'-DFUR following 5-FU and CDDP was performed. Thirteen months after surgery, cancer recurrence was suspected due to elevated levels of the serum tumor markers carcinoembryonic antigen (8.9 ng/ml) and alpha fetoprotein (85.8 ng/ml). She was additionally treated with UFT 300 mg/day and Lentinan 2 mg/week. The serum tumor markers decreased gradually returned to normal levels. At 5 years and 8 months after surgery, she is alive without any sign of recurrence.  相似文献   
106.
107.
PURPOSE: To prospectively determine the magnetic resonance (MR) signal intensity characteristics of structures of the ampullary region and to assess the potential use of MR imaging in evaluation of the extent of periampullary tumors in resected specimens. MATERIALS AND METHODS: Twenty-five specimens from the ampullary region obtained in four autopsy cases without periampullary tumors and in 21 patients with periampullary tumors were examined with a 1.5-T MR system and a circular surface coil with 5-inch (12.7-cm) diameter. High-spatial-resolution MR images were obtained with field of view of 100 x 100 mm, matrix of 256 x 256 or 512 x 256, and section thickness of 2 mm. MR imaging findings were compared with histopathologic findings. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of high-spatial-resolution MR imaging for assessment of tumor invasion into surrounding tissues were evaluated by two radiologists. RESULTS: T1- and T2-weighted MR images clearly depicted normal structures in the ampullary region that included Oddi muscle, duodenal wall, common bile duct, and pancreas; these findings corresponded well with histologic findings. In 20 (95%) of 21 tumors, high-spatial-resolution MR imaging depicted location and extension of periampullary tumors precisely. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of high-spatial-resolution MR imaging for assessment of tumor invasion into surrounding tissue were 88%, 100%, 96%, 100%, and 94%, respectively. CONCLUSION: In this study, MR imaging correctly depicted location, extension, and origin of tumor. High-spatial-resolution MR imaging has potential for presurgical staging of tumors in this region.  相似文献   
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110.
We constructed full-length enriched cDNA libraries from chimpanzee brain, skin, and liver tissues by the oligo-capping method to establish a database of sequences of chimpanzee genes. Randomly selected clones from the libraries were subjected to one-pass sequencing from their 5'-ends. As a result, we collected 6813 chimpanzee cDNA sequences longer than 400 bp. Homology search against human mRNA sequences (RefSeq mRNAs) revealed that our collection included sequences of 1652 putative chimpanzee genes. In order to calculate the sequence identity between human and chimpanzee homologs, we constructed 5'-end consensus sequences of 226 chimpanzee genes by aligning at least three sequences for individual genes. Sequence identity was estimated by comparing these consensus sequences and the corresponding sequences of their human homologs. The average sequence identity of the 5'-end cDNAs was 99.30%. Those of the 5'-UTRs and CDSs were 98.79% and 99.42%, respectively. The results confirmed that human and chimpanzee genes are highly conserved at the nucleotide level. As for amino acids, the average sequence identity was 99.44%. The average synonymous (K(S)) and nonsynonymous (K(A)) divergences were estimated to be 1.33% and 0.28%, respectively.  相似文献   
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