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61.
Wang DS Stolpen AH Bird VG Ishigami K Rayhill SC Winfield HN 《Journal of endourology / Endourological Society》2005,19(2):193-199
BACKGROUND AND PURPOSE: Contrast-enhanced three-dimensional magnetic resonance angiography (3D-MRA) with image reconstruction has important applications in laparoscopic urologic surgery. We now use 3D-MRA as part of our preoperative evaluation in selected patients undergoing laparoscopic donor nephrectomy, pyeloplasty, radical nephrectomy, and partial nephrectomy. PATIENTS AND METHODS: From June 2001 to December 2002, 50 patients underwent preoperative 3D-MRA at 1.5 T prior to laparoscopic renal surgery. In general, preoperative 3D-MRA was obtained for donor nephrectomies and pyeloplasties and for cases where prior imaging suggested a possible vascular anomaly. Patients who underwent preoperative imaging included those having donor nephrectomy (N = 28), pyeloplasty (N = 12), radical nephrectomy (N = 5), partial nephrectomy (N = 3), and other laparoscopic renal procedures (N = 2). The 3D-MRA studies were interpreted by one radiologist, and all laparoscopic cases were performed by one of two surgeons. The findings of 3D-MRA were correlated with the intraoperative findings with special attention to aberrant vasculature, including duplicated renal arteries or veins, accessory vessels, or crossing vessels. RESULTS: Among patients undergoing laparoscopic donor nephrectomy, 3D-MRA correctly predicted the number of renal vessels in 27 of 28 cases (96%), including all 3 cases of left retroaortic renal vein. Also, 3DMRA correctly predicted the presence or absence of a crossing vessel in 10 of 12 cases (83%) of laparoscopic pyeloplasty. The imaging study also correctly predicted the number of hilar vessels in all five cases of radical nephrectomy, all three cases of partial nephrectomy, and both cases of other renal operations. Overall, 3D-MRA correctly defined the renal hilar anatomy in 48 of 50 patients, for an overall accuracy of 96%. CONCLUSIONS: Three-dimensional MRA findings correlate well (96%) with intraoperative findings in laparoscopic renal surgery. The imaging study provides exquisite vascular detail and is highly accurate, making it sufficient imaging prior to laparoscopic donor nephrectomy and useful for pyeloplasty and other complex renal operations. 相似文献
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S Kamidono S Arakawa A Fujii N Kataoka K Umezu J Ishigami K Hirooka N Shimatani M Matsushita K Hikosaka 《The Japanese journal of antibiotics》1985,38(10):2735-2769
To objectively evaluated the usefulness of the standard formulation of cefaclor (CCL) and the long-acting formulation of cefaclor (S6472) in noncatheterized complicated urinary tract infection (UTI), a double-blind comparison study was carried out using cephalexin (CEX) as a control. Patients were orally treated with either 500 mg of CCL 3 times/day, 750 mg of S6472 2 times/day, or 500 mg of CEX 4 times/day for 14 days. Overall clinical effect was evaluated on days 5 and 14 in accordance with the UTI therapeutic evaluation standard, with check for recurrence on day 21. There was no demographic difference between the groups. There was no difference in the effective rate on day 5 among the 3 treatment groups: 58.1% in S6472 group, 66.0% in CCL group and 61.9% in CEX group. Nor on day 14, was there any significant difference in the effective rate among the 3 groups: 70.8% in S6472 group, 63.4% in CCL group and 61.8% in CEX group. Stratification analyses (by UTI group, infection site, in- or out-patient, time of starting treatment, pretreatment severity of pyuria, total number of bacteria before treatment) revealed no significant difference among the 3 groups. Therapeutic effect evaluated by physicians in charge was not significantly different among the 3 groups on day 5 or day 14. In terms of overall therapeutic effect, all 3 products were very effective in patients infected with sensitive bacteria: On day 5, 85.4% in S6472 group, 84.4% in CCL group, and 83.7% in CEX group. There was no significant difference among the 3 groups on either day. The incidence of side effects was not significantly different among the 3 groups: 4 out of 129 patients treated with S6472 (3.1%), 2 of 131 treated with CCL (1.5%) and 2 of 128 with CEX (1.6%). Clinical laboratory tests revealed 4 abnormal findings in 4 patients treated with S6472, 6 findings in 4 treated with CCL, and 4 findings in 2 treated with CEX, showing no significant difference in incidence among the 3 groups. Both side effects and abnormal clinical laboratory findings were mild and reversible. Physicians in charge judged the usefulness of the 3 drugs on days 5 and 14, taking efficacy and safety into consideration. Significant difference was not observed. The presence of recurrence was examined 7 days after drug withdrawal in patients regarded as remarkable responders to 14-day treatment by overall therapeutic effect evaluation.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
64.
Ishigami A Ohsawa T Hiratsuka M Taguchi H Kobayashi S Saito Y Murayama S Asaga H Toda T Kimura N Maruyama N 《Journal of neuroscience research》2005,80(1):120-128
Citrullinated proteins are the products of a posttranslational process in which arginine residues undergo modification into citrulline residues when catalyzed by peptidylarginine deiminases (PADs) in a calcium ion-dependent manner. In our previous report, PAD2 expressed mainly in the rat cerebrum became activated early in the neurodegenerative process. To elucidate the involvement of protein citrullination in human neuronal degeneration, we examined whether citrullinated proteins are produced during Alzheimer's disease (AD). By Western blot analysis with antimodified citrulline antibody, citrullinated proteins of varied molecular weights were detected in hippocampal tissues from patients with AD but not normal humans. Two of the citrullinated proteins were identified as vimentin and glial fibrillary acidic protein (GFAP) by using two-dimensional gel electrophoresis and MALDI-TOF mass spectrometry. Interestingly, PAD2 was detected in hippocampal extracts from AD and normal brains, but the amount of PAD2 in the AD tissue was markedly greater. Histochemical analysis revealed citrullinated proteins throughout the hippocampus, especially in the dentate gyrus and stratum radiatum of CA1 and CA2 areas. However, no citrullinated proteins were detected in the normal hippocampus. PAD2 immunoreactivity was also ubiquitous throughout both the AD and the normal hippocampal areas. PAD2 enrichment coincided well with citrullinated protein positivity. Double immunofluorescence staining revealed that citrullinated protein- and PAD2-positive cells also coincided with GFAP-positive cells, but not all GFAP-positive cells were positive for PAD2. As with GFAP, which is an astrocyte-specific marker protein, PAD2 is distributed mainly in astrocytes. These collective results, the abnormal accumulation of citrullinated proteins and abnormal activation of PAD2 in hippocampi of patients with AD, strongly suggest that PAD has an important role in the onset and progression of AD and that citrullinated proteins may become a useful marker for human neurodegenerative diseases. 相似文献
65.
Ishigami K Stolpen AH Al-Kass FM Zhang Y Rayhill SC Katz DA Abu-Yousef M 《Journal of computer assisted tomography》2005,29(4):464-471
PURPOSE: To evaluate the accuracy and clinical role of gadolinium-enhanced 3D magnetic resonance angiography (MRA) in patients with suspected hepatic arterial complications after liver transplantation. MATERIALS AND METHODS: Thirty-six consecutive MRA studies were performed in 33 liver transplant recipients after transplantation. MRA image quality was assessed subjectively. Thirty-two MRA studies were retrospectively reviewed and correlated with surgery (n = 2), conventional angiography (n = 18), or clinical follow-up (n = 12). MRA findings were also correlated with those of Doppler sonography in 30 of the cases. In 20 cases, concordance between MRA and surgery or conventional angiography was evaluated for each grade of hepatic artery stenosis (normal, mild [<50%], moderate [50-75%], severe [>75%], or occluded). RESULTS: MRA image quality was degraded 13 of 36 cases (36.1%) studies. The sensitivity, specificity, and accuracy of MRA by consensus reading for more than 50% of hepatic artery stenosis or occlusion were 67%, 90%, and 81.3%, respectively. Of the 19 cases in which Doppler sonography was abnormal, MRA correctly characterized hepatic artery stenosis in 16 (84.2%). MRA also correctly identified all 5 occurrences of celiac artery stenosis. However, MRA overestimated the severity of hepatic arterial stenosis in 3 (15%) of 20 cases and underestimated 5 (25%) of 20 cases. CONCLUSION: MRA complements Doppler ultrasound to exclude significant hepatic artery stenosis. However, a substantial number of MRA studies were technically inadequate, and MRA demonstrated limited efficacy for correctly grading the severity of hepatic artery stenosis. 相似文献
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68.
Yukawa M McCormick WC Rajan S Matsumoto AM Wallace JI Pearlman RA Weigle DS 《Journal of the American Geriatrics Society》2002,50(9):1566-1571
OBJECTIVES: To determine the relationship between leptin and unintentional weight loss in older adults. DESIGN: Prospective cohort study over 2 years. SETTING: University-affiliated Veterans Affairs Medical Center. PARTICIPANTS: The subjects were 105 community-dwelling male veterans aged 65 and older who had participated in a prospective cohort study on nutrition and health conducted at the Veterans Affairs Puget Sound Health Care System from 1986 to 1989. MEASUREMENTS: Anthropometric data and fasting blood specimens were collected at baseline and annually for the subsequent 2 years. Stored blood specimens were analyzed for leptin, insulin, glucose, C-reactive protein, sex hormone binding globulin, and testosterone levels. RESULTS: Over 2 years, 75 men were weight stable (weight loss <4% of baseline) and 30 men had unintentional weight loss (weight loss>4% of baseline). The baseline body mass index (BMI) and leptin levels for the two groups were not statistically different. Positive correlations existed between leptin level and BMI at each time point for weight-stable and weight-loss subjects. Furthermore, a significant relationship existed between changes in leptin and changes in BMI over 1 year in multiple regression analysis (r =.436, P <.001 after the first year; and r =.630, P =.027 after the second year). CONCLUSIONS: Like in younger adults, plasma leptin levels remained proportional to BMI, and changes in BMI were accurately reflected by changes in leptin levels in older individuals. Fasting leptin levels did not predict involuntary weight loss over 2 years of follow-up. 相似文献
69.
Okamoto Y Yuki M Imai R Shinki Y Yamanaka M Masutani T 《Rinsho byori. The Japanese journal of clinical pathology》2002,50(12):1150-1153
We developed a simple method to eliminate electrocardiogram (ECG) artifacts from electroencephalogram (EEG) records by using simultaneously recorded ECG data. The raw EEG data, the real EEG data and the ECG data were regarded as multi-dimensional vectors Ea, Er and C, respectively. Also, the ECG data, with reduced amplitude whose coefficient was denoted as 'k', were assumed to be overlapped on the real EEG. These assumptions introduced the equations [Ea = Er + k.C], [Er.C = 0] and finally [k = Ea. C/C.C]. This calculation method was implemented by a Macintosh computer using data exported from digital EEG recordings (sampled at 200 Hz with 16-bit resolution). In several subjects, sampling intervals of 5 or 10 seconds for calculation succeeded in eliminating ECG artifacts. However, regardless of the sampling interval, this elimination condition was not always efficient in several other subjects, including a brain-dead patient. It was suggested that the ECG data used were insufficient for the calculation, because only one hand-to-hand reference was used for simultaneous recording, as usual. This one ECG reference was able to express only one ECG projection. Then two other hand-to-foot references of ECG were added to the recordings, and the elimination procedure was performed using all of the simultaneously recorded ECG data at the three references. Consequently, elimination was much improved in most subjects, including the brain-dead patient. Our method may be useful for eliminating ECG artifacts without changing reference electrodes. 相似文献
70.
BACKGROUND: Warm ischemia of the graft from non-heart-beating donors is considered a risk factor for posttransplant graft dysfunction. The early administration of cytoprotective agents may help improve graft dysfunction. METHODS: Four groups of 10 pigs each underwent orthotopic liver transplantation. Prostaglandin I2 analogue, OP-41483, was administered intraportally 30 min before warm ischemic insult in donors and after reperfusion in recipients in one group. In the other study group, additional intravenous tauroursodeoxycholic acid (TUDC) was given before the warm ischemic insult in donors and after reperfusion, then maintained continuously until postoperative day (POD) 7. RESULTS: Exposure of liver grafts to warm ischemia resulted in severe congestion with the disappearance of thrombomodulin (Tm) from the sinusoidal endothelial cells (SECs) and smooth muscle cells (SMCs) around biliary epithelial cells (BEpCs) 2 hr after reperfusion, followed by positive immunoreactivity of Tm in BEpCs with hyperbilirubinemia, which was related to high mortality. Combined administration of OP-41483 and TUDC had a protective effect, demonstrated by sustained immunoreactivity of Tm from SECs and SMCs until POD 7, without that reactivity in BEpCs. This was associated with reduced congestion and hyperbilirubinemia, similar to the control group not subjected to warm ischemia. CONCLUSIONS: These findings suggest that negative immunoreactivity of Tm in SECs and SMCs surrounding BEpCs and positive in BEpCs may be an early marker for ischemic liver injury, and that OP-41483 and TUDC may protect against the microcirculatory and biliary derangement. 相似文献