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991.
992.
993.
PURPOSE: To determine the biochemical characteristics of lung cancer tissue using in vitro (1)H-MRS, and investigate the correlation between survival probabilities and lactate (Lac), creatine (Cr), and choline (Cho) concentrations measured by in vitro (1)H-MRS. MATERIALS AND METHODS: A total of 21 patients with lung cancer were included in this retrospective study. (1)H-MRS spectra measurements were performed at 6.35T using a JNM-EX270, high-resolution FT-NMR spectrometer. RESULTS: When normal lung tissue was compared with lung cancer tissue, significant differences were noted most consistently in the levels of Lac and Cho, with lung cancer tissue showing higher values than normal lung tissue. Lac concentrations of lung cancer tissue were significantly higher in patients with recurrence compared to patients without recurrence (0.285 +/- 0.096 mumol/g). The mean overall survival of patients in the low-Lac group was 50.28 +/- 6.47 months, which is significantly higher compared to the high-Lac group, which had a mean survival time of only 30.49 +/- 5.41 months. CONCLUSION: Kaplan-Meier analysis of the data showed that the overall and disease-free survival probabilities were significantly higher in patients with low tumor Lac values than in those with high tumor Lac concentrations.  相似文献   
994.
PURPOSE: To investigate the relationship between the tumor size of breast cancer by palpation and the sensitivity of mammography (MMG) and ultrasonography (US), and which modality can detect nonpalpable breast cancer in women aged 30 to 39 years. METHODS: We retrospectively evaluated the tumor size by palpation, breast density, and the sensitivity of MMG and US in 165 patients aged 30 to 39 years. Palpation, US, and MMG were performed with prior knowledge of the results of other modalities. The tumor size on palpation were classified into Tnp; nonpalpable, T1p; 2 cm or less, T2p; more than 2 cm, but not more than 5 cm, and T3p; more than 5 cm. RESULTS: Of 165 patients, 147 patients (89%) showed mammographically dense breasts. Of 165 cancers, 14 (8%) were Tnp, 40 (24%) were T1p, 82 (50%) were T2p, and 29 (18%) were T3p. The sensitivity of MMG was 57% (8 of 14) for Tnp, 78% (31 of 40) for T1p, 90% (74 of 82) for T2p, and 97% (28 of 29) for T3p. The sensitivity of US was 43% (6 of 14) for Tnp and 100% for palpable cancers. Of 14 nonpalpable cancers, 4 (29%), 4 (29%), and 2 (14%) could be detected by only MMG, bloody nipple discharge, and US. CONCLUSIONS: The sensitivity of MMG depends on the tumor size on palpation in this age range. MMG fails to detect relatively large palpable cancers. On the other hand, US can detect all palpable cancers. However, the sensitivity of US declines for nonpalpable cancers. For the detection of nonpalpable cancers, MMG, US, and nipple discharge are complementary modalities.  相似文献   
995.
We studied the efficacy and safety of docetaxel (DOC) for elderly breast cancer patients. Between September 1997 and June 2003, five consecutive women with advanced breast cancers who were 75 years of age or older received DOC at a dose of 60 mg/m(2) every three weeks. No premedications to prevent hypersensitive reactions and fluid retention by DOC were given. The number of DOC dosages per case was 5-16 times (12 times the median) and the relative dose intensity (RDI) was 80-100% (95% of medians). Objective partial responses were observed in all patients. The median time to partial response was 21 days (range: 21-50 days). The median time to treatment failure was 12 months (range: 5-22 months). The grade and the frequency of major side effects were the following: leukocytopenia of grade 3 (80%), edema of grade 2-3 (40%), and alopecia of grade 2 (100%). It was concluded from these findings that DOC could be safely and effectively administered to elderly advanced breast cancer patients.  相似文献   
996.
We used S-1 chemotherapy to treat 5 patients with cancer of the gastric tube used for esophageal reconstruction through the posterior mediastinal route following surgery for esophageal cancer. The response rate was 40%, the median survival 15 months, and 3 patients still survive. In those 3 patients, the gastric tube cancer was at a resectable stage, but the patients elected to have chemotherapy instead. One patient has survived 21 months after responding completely to 2 cycles of combined chemotherapy with S-1 and cisplatin. Another has survived 15 months after partially respondingto S-1 chemotherapy. And the third has survived 46 months after endoscopic treatment, radiation therapy and S-1 chemotherapy. S-1 chemotherapy thus appears to be an effective treatment for cancer of the gastric tube after surgery for esophageal cancer.  相似文献   
997.
In this study, we investigated a short-term outcome of 56 cases of ESD for early gastric cancer performed in our department concerning the tumor diameter within or over 20 mm. Seventeen lesions were larger than 21 mm (large group), and 39 lesions were within 20 mm (indication group). There was no significant difference in the background factors between the two groups. The mean operating time and median of post operative hospital stay of the large group were longer than those of the indication group, and those differences were statistically significant. On the other hand, no significant difference was seen in the rate of one-piece resection, the incidence of complications and curability. With a further improvement of our skills, an ESD application in a case where the tumor diameter is larger than 21 mm may be extended.  相似文献   
998.
We present a case of deep venous thrombosis (DVT) during pegylated interferon (peg-IFN)-α2b plus ribavirin treatment of chronic hepatitis C (CHC). A 67-year-old man, who had been under treatment for hypertension and diabetes mellitus, was admitted to our hospital for peg-IFN-α2b plus ribavirin treatment for CHC. His serum hepatitis C virus (HCV) RNA level became undetectable 1 week after the initiation of peg-IFN-α2b plus ribavirin treatment. He suffered from severe pain, flare, and edema in both of his lower legs 6 weeks after the initiation of peg-IFN-α2b plus ribavirin treatment. He was diagnosed as having DVT because of the presence of a thrombus in the right soleus vein by ultrasonography. Peg-IFN-α2b plus ribavirin treatment was discontinued because a causal relationship between DVT and peg-IFN-α2b plus ribavirin treatment was suspected. DVT was not observed and the symptoms in both of his legs were improved after the administration of warfarin potassium. Subsequently, DVT has not recurred, and he has remained HCV-RNA negative.  相似文献   
999.
The RNase III endonuclease Dicer plays a key role in generation of microRNAs (miRs). We hypothesized that Dicer regulates cancer cell susceptibility to immune surveillance through miR processing. Indeed, Dicer disruption up-regulated intercellular cell adhesion molecule (ICAM)-1 and enhanced the susceptibility of tumor cells to antigen-specific lysis by cytotoxic T-lymphocytes (CTLs), while expression of other immunoregulatory proteins examined was not affected. Blockade of ICAM-1 inhibited the specific lysis of CTLs against Dicer-disrupted cells, indicating a pivotal role of ICAM-1 in the interaction between tumor cells and CTL. Both miR-222 and -339 are down-regulated in Dicer-disrupted cells and directly interacted with the 3′ untranslated region (UTR) of ICAM-1 mRNA. Modulation of Dicer or these miRs inversely correlated with ICAM-1 protein expression and susceptibility of U87 glioma cells to CTL-mediated cytolysis while ICAM-1 mRNA levels remained stable. Immunohistochemical and in situ hybridization analyses of 30 primary glioblastoma tissues demonstrated that expression of Dicer, miR-222, or miR-339 was inversely associated with ICAM-1 expression. Taken together, Dicer is responsible for the generation of the mature miR-222 and -339, which suppress ICAM-1 expression on tumor cells, thereby down-regulating the susceptibility of tumor cells to CTL-mediated cytolysis. This study suggests development of novel miR-targeted therapy to promote cytolysis of tumor cells.  相似文献   
1000.
The objective was to compare brain perfusion image using 3-dimensional stereotactic surface projection analysis of N-isopropyl-p-123I iodoamphetamine single photon emission computed tomography between Parkinson's disease patients with a high frontal assessment battery score and those with a low frontal assessment battery score. Thirty nondemented patients with Parkinson's disease were studied. Patients were divided into 2 groups: a high-scoring group whose frontal assessment battery score was 12 or more and a low-scoring group whose frontal assessment battery score was 11 or less. The high-scoring group included 21 patients, and the low-scoring group included 9 patients. They underwent N-isopropyl-p-123I iodoamphetamine single photon emission computed tomography, and we analyzed the data by the 3-dimensional stereotactic surface projection method. Results showed that left inferior parietal lobule and left supramarginal gyrus perfusion of the low-scoring group were significantly decreased compared with the high-scoring group. It is concluded that patients with Parkinson's disease may have frontal lobe dysfunction, but the decreased frontal assessment battery score may be caused not by progressed frontal lobe dysfunction but by parietal lobe dysfunction added to their preexisting frontal lobe impairment.  相似文献   
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