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91.
PURPOSE: The traditional measure of success after exclusion and bypass of popliteal artery aneurysm (PAA) is graft patency. In addition to fate of the bypass, we hypothesize that late outcome after surgical treatment of PAA is influenced by completeness of exclusion. METHODS: Thirty patients who underwent 41 reconstructions for PAA over a 10-year period were reviewed. RESULTS: Excluded PAAs were examined with duplex ultrasound scan for size, patency, and patent feeding branches; bypass grafts and native inflow and outflow arteries were examined for patency and size. Thirty-six limbs were available for follow-up (mean follow-up period, 46 +/- 42 months). Only two aneurysms (5.6%) appeared patent on duplex ultrasound scan, but five limbs had patent arterial branches communicating with thrombosed excluded PAAs. PAA diameter decreased from 2.5 +/- 0.8 cm to 1.7 +/- 0.5 cm (P <.0001) in most. However, 12 excluded PAAs (33%) showed significant enlargement from 2.2 +/- 0.9 cm to 2.8 +/- 1.0 cm (P =.002). A quarter of enlarging excluded PAA were associated with new compressive symptoms. Three methods of PAA exclusion were used: proximal and distal ligation with short segment isolation (type 1), proximal and distal ligation with long segment isolation (type 2), and single ligature (type 3). In univariate analysis, type of exclusion significantly influenced late size of excluded PAA (P =.004). Type 1 exclusion was superior to both type 2 and 3 exclusions in producing aneurysm diameter reduction. Type 3 exclusion resulted in aneurysm growth. In addition, excluded aneurysms with visualized feeding branches were associated with significant growth compared with PAAs without feeding branches (P =.006). Graft primary and assisted primary patency rates at 5 years were 86% +/- 9.4% and 92% +/- 7.4%, respectively. Although graft diameter and native donor artery diameter significantly increased, this did not adversely affect graft patency. CONCLUSION: Enlargement of excluded PAA after surgical treatment can cause compressive symptoms. Exclusion requires adequate vascular isolation to prevent late PAA enlargement, with proximal and distal arterial ligation best performed adjacent to the aneurysm. Vein graft enlargement occurs, but this enlargement does not adversely influence patency.  相似文献   
92.
To further understand the temporal mode and mechanisms of coronary restenosis, 229 patients were studied by prospective angiographic follow-up on day 1 and at 1, 3 and 6 months and 1 year after successful percutaneous transluminal coronary angioplasty. Quantitative measurement of coronary stenosis was achieved by cinevideodensitometric analysis. Actuarial restenosis rate was 12.7% at 1 month, 43.0% at 3 months, 49.4% at 6 months and 52.5% at 1 year. In 219 patients followed up for greater than or equal to 3 months, mean stenosis diameter was 1.91 +/- 0.53 mm immediately after coronary angioplasty, 1.72 +/- 0.52 mm on day 1, 1.86 +/- 0.58 mm at 1 month and 1.43 +/- 0.67 mm at 3 months. In 149 patients followed up for greater than or equal to 6 months, mean stenosis diameter was 1.66 +/- 0.58 mm at 3 months and 1.66 +/- 0.62 mm at 6 months. In 73 patients followed up for 1 year, mean stenosis diameter was 1.65 +/- 0.56 mm at 6 months and 1.66 +/- 0.57 mm at 1 year. Thus, stenosis diameter decreased markedly between 1 month and 3 months after coronary angioplasty and reached a plateau thereafter. In conclusion, restenosis is most prevalent between 1 and 3 months and rarely occurs beyond 3 months after coronary angioplasty.  相似文献   
93.
BACKGROUND/AIMS: C-reactive protein (CRP) was recently identified as a prognostic factor for patients with hepatocellular carcinoma (HCC) after surgical resection. We investigated the relationship between the serum levels of high sensitivity CRP (H-CRP) and the prognosis of HCC patients. METHOD: We conducted a cohort study of 90 HCC patients enrolled from 1997 to 1998. All patients were treated and followed for a mean period of 3.2 years. Clinical variables were compared between patients positive for H-CRP (serum H-CRP levels >/=3.0 mg/L, n=47) and those negative for H-CRP (serum H-CRP levels <3.0 mg/L, n=43). We also determined the relationship between serum H-CRP and prognosis in HCC patients. RESULTS: The survival rate of patients of the H-CRP-positive group was lower than that of H-CRP-negative patients. Tumour stage (stages 3 or 4), total bilirubin >/=1.2 mg/dL, albumin (Alb) <3.5 g/dL, des-gamma-carboxy prothrombin >/=40 mAU/mL, positive H-CRP and initial treatment (transcatheter arterial chemoembolization, hepatic arterial infusion chemotherapy or best supportive care) were identified as significant poor prognostic factors by univariate analysis, while positive H-CRP [hazard ratio (HR), 1.58; P=0.048], Alb<3.5 g/dL (HR, 2.10; P=0.004), tumour stage (stages 3 or 4; HR, 3.05; P=0.001) and initial treatment (HR, 1.88; P=0.029) were considered to be significant determinants of poor prognosis by multivariate Cox proportional hazards analysis. CONCLUSIONS: The prognosis of H-CRP-positive patients was poorer compared with H-CRP-negative patients. This study confirmed that H-CRP, like CRP, is a marker of poor prognosis in HCC patients.  相似文献   
94.
In older people, falls are major reasons for transporting to emergency departments (ED). Falls are etiologically classified into syncopal falls and non-syncopal ones. The aim of this study is to clarify the characteristics of syncopal falls in community-living older people transported to ED. The retrospective chart review was performed on patients older than 65 years, transported to the ED of Keio University Hospital in Tokyo because of falls during a 12-month period. Age, sex, blood pressure and pulse rate at the arrival to ED, episode of syncope, type of fall, sustained injury and medical problems were screened. We analyzed the differences between syncopal falls and non-syncopal ones. Patients with syncopal falls were given blood tests, electrocardiograms, and standing tests for orthostatic hypotension. The number of syncopal falls was 33 (29.5%), and that of non-syncopal ones was 79 (69.3%). Syncopal falls frequently occurred on same level compared with from one level to another (84.8% versus 9.1%). In patients with syncopal falls, the frequency of falling on the same level was significantly higher than that in patients with non-syncopal falls (84.8% vs 60.8%). Patients with syncopal falls significantly sustained fewer fractures (12.1% vs 34.2%), and used more antihypertensive agents (45.5% vs 18.9%) than those with non-syncopal ones, respectively. The 14 syncopal fall patients were given standing tests, and four patients presented orthostatic hypotension. In community-living older people transported to ED, syncopal falls frequently occurred on the same level, and the patients with syncopal falls were found to have sustained fewer fractures and use more antihypertensive agents.  相似文献   
95.
Recent reports have linked the expression of specific microRNAs (miRNAs) with tumorigenesis and metastasis. Here, we show that microRNA (miR)-16, which is expressed at lower levels in prostate cancer cells, affects the proliferation of human prostate cancer cell lines both in vitro and in vivo. Transient transfection with synthetic miR-16 significantly reduced cell proliferation of 22Rv1, Du145, PPC-1, and PC-3M-luc cells. A prostate cancer xenograft model revealed that atelocollagen could efficiently deliver synthetic miR-16 to tumor cells on bone tissues in mice when injected into tail veins. In the therapeutic bone metastasis model, injection of miR-16 with atelocollagen via tail vein significantly inhibited the growth of prostate tumors in bone. Cell model studies indicate that miR-16 likely suppresses prostate tumor growth by regulating the expression of genes such as CDK1 and CDK2 associated with cell-cycle control and cellular proliferation. There is a trend toward lower miR-16 expression in human prostate tumors versus normal prostate tissues. Thus, this study indicates the therapeutic potential of miRNA in an animal model of cancer metastasis with systemic miRNA injection and suggest that systemic delivery of miR-16 could be used to treat patients with advanced prostate cancer.  相似文献   
96.
This study was designed to examine the effect of TJ-23 on the synthesis of acetylcholine menopausal rats. TJ-23 (500 mg/kg body weight) was administered daily through drinking water for either 1 or 3 months. Treatment with TJ-23 for 1 month resulted in an increase in the choline acetyltransferase (ChAT) activity in the ventral hippocampus, but there was no statistically significant change in the frontoparietal cerebral cortex. Treatment with TJ-23 for 3 months resulted in a decrease in the ChAT activity in the frontoparietal cortex, but there was no statistically significant change in the hippocampus. Furthermore, treatment with TJ-23 for 3 months resulted in a decrease in the ChAT activity in the amygdala-pyriform cortex complex. From these observations, it is inferred that TJ-23 treatment brings on the synthesis of acetylcholine in the frontoparietal cerebral cortex and hippocampus, and furthermore, treatment with the same regimen brings on different time sequences of acetylcholine synthesis in the frontoparietal cerebral cortex and hippocampus in menopausal rats.  相似文献   
97.
The progression from chronic hepatitis C virus (HCV) infection to hepatocellular carcinoma (HCC) has been reported. We evaluated whether co-infection with the human T-lymphotropic virus type I (HTLV-I) might be associated with this transition in a cross-sectional analysis of 127 patients with HCV-chronic hepatitis (mean age=51.7) and 43 patients with HCV-associated HCC (mean age=62.4); the seroprevalence of anti-HTLV-I was 9.5% and 30.2%, respectively. For subjects 50 years or older, the seroprevalence of anti-HTLV-I in HCC patients was 13/41 (31.7%) which was significantly higher than that in chronic hepatitis patients (6/82, 7.3%) ( P =0.001). The relative risk (RR) of association was 12.8 ( P =0.0004) among the males, however, no association was evident among the females, RR=1.3 ( P =0.80). The increased prevalence of HTLV-I positivity among the HCC cases could not be attributed to a higher rate of prior transfusion. These data suggest that co-infection with HTLV-I may contribute to the development of HCC among patients with HCV-induced chronic liver diseases in a highly HTLV-I-endemic area.  相似文献   
98.
Colchicine, a potent microtubule-depolymerizing agent, is well known to selectively kill dentate granule cells in the hippocampal formation in vivo. Using organotypic cultures of rat entorhino-hippocampal slices, we confirmed that in vitro exposure to 1 μM and 10 μM of colchicine reproduced a specific degeneration of the granule cells after 24 h. Similar results were obtained with other types of microtubule-disrupting agents, i.e., nocodazole, vinblastine, and Taxol. Interestingly, the actin-depolymerizing agents cytochalasin D and latrunculin A also elicited selective neurotoxicity in the dentate gyrus without affecting survival of hippocampal pyramidal cells. The selective pattern of degeneration was observable 24 h after a brief treatment with the toxins as short as 5 min, but this delayed neuronal death was unlikely to be a result of excitotoxicity because it was virtually unaffected by glutamate receptor antagonists, tetrodotoxin, or extracellular Ca2+-free conditions. The damaged tissues contained a large number of TUNEL-positive neurons and exhibited an increased level in caspase-3-like activity, suggesting that cytoskeleton disruption triggers an apoptosis-like process in dentate granule cells. Thus, this study may provide a basis for understanding the distinctive mechanism that supports granule cell survival.  相似文献   
99.
OBJECTIVE: Previous studies have suggested that several code types of the Minnesota Multiphasic Personality Inventory (MMPI) are useful markers for identifying schizophrenia. We hypothesized that schizotypal disorder (STD) patients with such schizophrenia-related code types have the morphological brain abnormalities associated with schizophrenia. METHOD: Voxel-based morphometric analysis with statistical parametric mapping (SPM) 99 software was used to investigate the differences in brain morphology between 14 STD patients with the schizophrenia-related code types of the MMPI and 28 normal individuals. RESULTS: The STD patients showed significantly decreased gray matter volume in the insular regions bilaterally and in the left entorhinal cortex, compared with the controls. CONCLUSION: Our findings suggest that STD patients with the schizophrenia-related code types have volume reductions in these regions as an endophenotype that overlaps with schizophrenia.  相似文献   
100.
In vivo brain imaging and postmortem investigations have demonstrated ventricular enlargement in the brains of schizophrenic patients. However, the extent of changes in the volume of discrete ventricle subdivisions has not been clearly established. We conducted high-resolution three-dimensional magnetic resonance imaging in 40 schizophrenic patients (20 males and 20 females) and 40 healthy volunteers (20 males and 20 females). The lateral ventricle in each hemisphere was divided into the anterior horn, body, posterior horn and temporal horn. The volumes of the hemispheres, four subdivisions of the lateral ventricles and the third ventricle were measured. Compared to the control subjects, the bilateral hemisphere volumes were significantly lower in the patients than in the control subjects. In the lateral ventricular subdivisions of the male patients, the most substantial volume increase was in the left temporal horn, and volume increases were also observed in the bilateral anterior horns and the right body. The male patients also had a significantly increased volume of the third ventricle. The female patients showed similar patterns with less statistical significance. Thus, the schizophrenia patients showed ventricular enlargement, particularly in the left temporal horn, being more severely affected in the male than in the female.  相似文献   
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