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91.
OBJECTIVE: To evaluate the long-term effects of trabeculectomy on the progression of visual field damage in patients with progressive normal-tension glaucoma (NTG). DESIGN: Retrospective, noncomparative, interventional case series. PARTICIPANTS: Twenty-three patients with NTG who had significant progression of visual field damage preoperatively and underwent trabeculectomy using antimetabolites. METHODS: Visual field testing using the Humphrey Visual Field Analyzer was periodically performed before and for at least 5 years after surgery (mean, 6 years). The time course of the mean deviation (MD) and mean of total deviations (TD(mean)) in four separate subfields, superior and inferior cecocentral and superior and inferior arcuate fields, were analyzed using a linear mixed effects model. MAIN OUTCOME MEASURES: Intraocular pressure (IOP), preoperative and postoperative regression coefficients of the time course of MD or TD(mean) in the four subfields, corresponding to the rate of progression of visual field damage. RESULTS: IOP significantly decreased from 16.2 +/- 1.8 mmHg preoperatively to approximately 11 mmHg during the postoperative follow-up period (P < 0.001). The preoperative regression coefficient of MD change was significantly negative (-1.05 [95% confidence interval, -1.28 to -0.82] dB/year, P < 0.001). After surgery, it increased significantly to -0.44 (95% confidence interval, -0.64 to -0.24) dB/year (P < 0.001), but the postoperative value was still significantly negative (P < 0.001). In the superior cecocentral, superior and inferior arcuate fields, preoperative regression coefficients of TD(mean) change were significantly negative (P < 0.001) and significantly increased after surgery (P < 0.01). In the inferior cecocentral field, the preoperative regression coefficient was not significantly different from 0 (P = 0.72) and did not change significantly after surgery (P = 0.15). CONCLUSIONS: Trabeculectomy was statistically associated with slowing further progression of visual field damage in patients with progressive NTG. The progression, however, did not completely stop over the 6-year postoperative follow-up period.  相似文献   
92.
In order to update the findings of relative risk associated with cigarette smoking for lung cancer by histologic type in Japan, the data from a population-based cohort study of 91,738 men and women were analyzed. During 1990-1999, 422 lung cancer incident cases were identified. The relative risk for all incident cases associated with current smokers versus non-smokers was 4.5 [95% confidence interval (CI): 3.0-6.8] and 4.2 (95% CI: 2.4-7.2), for men and women, respectively. When divided by histologic type, relative risk for squamous cell carcinoma and small cell carcinoma was 12.7 (95% CI: 4.7-34.7) and 17.5 (95% CI: 4.9-62.1), while for adenocarcinoma it was 2.8 (95% CI: 1.6-4.9) and 2.0 (95% CI: 0.8-5.0) for men and women, respectively. We confirmed that the lung cancer risk in men rose with increasing cigarette smoking, especially the duration of smoking among current smokers and decreased after the cessation of smoking among former smokers. Unlike the US or European countries, the relative risk did not increase in this updated study, compared with previous studies in 1960s to 1990s in Japan either for all incident cases or for specific histologic types and the magnitude of relative risks was substantially lower than that observed in the US or European countries, especially for adenocarcinoma.  相似文献   
93.
Human Valpha24 NKT cells bearing an invariant Valpha24JalphaQ antigen receptor, the counterpart of murine Valpha14 NKT cells, are activated by a specific ligand, alpha-GalCer, in a CD1d-dependent manner. Here, we demonstrate decreased numbers of circulating Valpha24 NKT cells in patients with primary lung cancer compared to healthy volunteers. However, Valpha24 NKT cells and DCs from lung cancer patients were functionally normal, even in the presence of tumor. Furthermore, levels of Valpha24 NKT cells in surgically resected lung tissue appeared to be equivalent to those of Valpha14 NKT cells in the mouse lung. Levels of Valpha24 NKT cells in the tumor tissue itself were increased about 2.5 times. Administration of alpha-GalCer-pulsed DCs expanded Valpha14 NKT cells in the lung more than 10 times, and the increased levels were sustained for 1 week. This may explain the previous finding that alpha-GalCer-pulsed DCs exerted strong antitumor activity in mouse lung tumor metastatic models. The potential use of alpha-GalCer-pulsed DCs for immunotherapy aimed at activating endogenous Valpha24 NKT cells in the lung of cancer patients is discussed.  相似文献   
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96.
OBJECTIVE: To determine the methodological usefulness of non-ischemic complete enucleation for small renal cell carcinomas (RCC) using a microwave tissue coagulator (MTC). METHODS: Fifty-nine patients (61 kidneys) underwent non-ischemic complete tumor enucleation by MTC. Of the 59 patients, 46 had an elective indication and 15 kidneys of 13 patients had an imperative indication. RCC was exposed with minimal peri-renal detachment. The demarcation line, 7-10 mm from the tumor, was coagulated at 8-10 mm intervals with a microwave antenna needle for 30-40 s at 50-60 W. The renal tumor was excised along the coagulated zone with normal surrounding tissue. The enucleation bed was covered with fibrin glue or fat tissue without approximation. RESULTS: The operations were successfully completed in all intended cases. The mean operation time was 160 +/- 43 (median: 160) min and the mean blood loss was 313 +/- 370 (median: 158) ml. No major bleeding or urine leakage from the enucleation bed was observed in 62.2 and 88.5% of cases, respectively. The minor bleeding and urine leakage were controlled easily with absorbable sutures. None of the cases presented with postoperative bleeding or urine leakage from the enucleation bed. Severe impairment of the renal function was not observed in any case evaluated by means of serum creatinine, creatinine clearance and radioisotope examination. The 5-year overall survival rate was 87% without recurrence up to 23.1 +/- 19.5 months of the mean follow-up. CONCLUSION: Non-ischemic complete tumor enucleation using MTC constitutes a simple, reliable and less invasive alternative to ordinary nephron-sparing surgeries for small RCC.  相似文献   
97.
BACKGROUND: Transcatheter arterial embolization induces marked antitumor response in patients with hepatocellular carcinoma, but the survival benefit of transcatheter arterial embolization remains to be determined. This study investigated prognostic factors in patients with advanced hepatocellular carcinoma treated by transcatheter arterial embolization. METHODS: A total of 128 consecutive patients with non-resectable hepatocellular carcinoma, who had undergone transcatheter arterial embolization between May 1990 and August 1998, were analyzed to investigate prognostic factors. RESULTS: Median survival time and survival proportions at 1, 3 and 5 years were 3.3 years, 92.0, 54.6 and 23.4%, respectively. By multivariate analysis using the accelerated failure time model, age <60 years, hepatitis C virus antibody positivity, serum albumin >3.5 g/dl, absence of portal vein invasion and serum alpha-fetoprotein level <400 ng/ml were significantly associated with favorable survival. For clinical application, we also propose a prognostic equation with combination of specific prognostic factors, by which survival curves of each patient could be predicted directly. CONCLUSION: The findings of the current study may be helpful in predicting the life expectancy of hepatocellular carcinoma patients treated by transcatheter arterial embolization and in designing future clinical trials of transcatheter arterial embolization for hepatocellular carcinoma.  相似文献   
98.
In Japan, 41% of surgeries for breast cancer were breast conserving treatment (BCT) in 2000. The indications for BCT in the guidelines of the Japanese Breast Cancer Society (1999) are as follows: (1) tumor size is 3 cm or less, (2) image diagnosis indicates no sign of extensive intraductal spread, (3) cases with multiple tumor are excluded, (4) radiation therapy is possible, (5) the patient wants to receive BCT. The pathological negative margin is favorable in BCT; however, we estimate based on our study that only about 30% of all breast cancers can be completely resected by partial mastectomy. To extend the indications for BCT, the roles of postoperative radiotherapy, endocrine therapy and preoperative chemotherapy will be important. Patients with ipsilateral breast tumor recurrence (IBTR) have increased risk of distant metastases, and the presence of IBTR is an important predictive factor for distant metastases. When we discuss the indications and limits of BCT, we have to take the rate of IBTR into careful consideration.  相似文献   
99.
AIM:To analyze the relationship between sperm mitochondrial membrane potential and sperm motility parameters by means of a computer-assisted sperm analyzer (CASA) and in-vitro fertilization rate(%FR). METHODS: Semen samples were obtained from 26 men undergoing in vitro fertilization-embryo transfer (IVF-ET). Informed consent was obtained from all men prior to the study. Samples were prepared using wash and swim-up method in HEPES-HTF medium. The sperm motility (%MOT), progressive motility (%PMOT), average path velocity (VAP) microm/s), straight line velocity (VSL) (micro m/s), curvilinear velocity (VCL) (microm/s) and %hyperactivated sperm (%HA), and the %FR were assessed. The samples were incubated in the presence of 2.0 mciromol/L of 5,5',6,6'-tetra-chloro-1,1',3,3'-tetraethylbenzimidazolyl-carbocyanine iodide (JC-1) for 30 min at 37 degrees C in air and washed in PBS before flow cytometry (FACSCalibur: Becton Dickinson) analysis. The mitochondrial probe JC-1 was used to identify the mitochondrial membrane potential. The sperm was divided into three populations according to the fluorescence pattern as follows: the high mitochondrial membrane potential group (n=8), the moderate group (n=5), and the low group (n=13). Statistical analysis was performed using unpaired t-test. RESULTS:Significant differences were found between the high and the low groups in %MOT (91.1+/-8.5 vs 63.0+/-32.7, mean+/-SD), VAP (73.0+/-14.2 vs 52.1+/-12.5), VCL (127.0+/-28.1 vs 87.0+/-22.6), %HA (27.3+/-23.6 vs 7.2+/-9.0) and %FR [73.2 (48/56) vs 59.0 (69/117)]. No significant differences were found in other CASA parameters. CONCLUSION: When the sperm mitochondrial membrane potential increases, sperm motility parameters and fertility potential will also increase. The JC-1 dye method is useful to predict sperm fertility potential.  相似文献   
100.
The immunosuppressive drug cyclosporine A (CsA) has been used in both organ transplantation and the treatment of autoimmune disorders. However, the drug causes adverse effects in the kidney, liver and nervous system, characterized by cellular loss in the affected area. Apoptosis has been shown to play a role in CsA-induced cytotoxicity. Because permeabilization of the mitochondrial membrane is a common criterion in most apoptotic settings in vertebrate cells, here we evaluated whether CsA causes loss of mitochondrial function in the pathway leading to cellular cytotoxicity. We found that CsA caused a concentration- and time-dependent loss of cell viability in the U937 cell line. Treatment of cells at a dose of 10 microM CsA resulted in G0/G1 arrest with a concurrent decrease in the number of cells in the S and G2/M phases of the cell cycle. In mechanistic studies related to the loss of viability, treating cells with 10 microM CsA for 24 h resulted in both DNA fragmentation and an increase of annexin-V-positive cells. CsA treatment also increased activity of the cysteine protease caspase-3, decreased the mitochondrial membrane potential and induced the release of cytochrome c into the cytosol. Furthermore, CsA treatment increased the number of cells in the sub-G0/G1 peak, indicative of a reduction in DNA, although this increase was not observed when cells were pre-treated with a broad caspase inhibitor. In the study, we also found that a higher dose of CsA induces LDH release when the cells were incubated for a longer period. Taken together, these data suggest that the mode of cell death induced by CsA is dose- and time-dependent. Short-term incubation with lower doses of CsA arrests cell growth; this arrest overlaps with the occurrence of apoptosis and then with necrosis after longer treatment periods with higher doses of CsA.  相似文献   
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