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91.

Objectives

The purpose of this study was to compare the degree of colorectal distention between manual insufflation using room air and automatic insufflation using carbon dioxide for computed tomography colonography performed as a preoperative examination for patients with colon cancer.

Materials and methods

Participants comprised 200 patients who underwent computed tomography colonography immediately after colonoscopy from October 2011–2012. The first 100 patients were examined using manual insufflation, and the remaining 100 patients were examined using automated insufflation. Two radiologists independently assessed colorectal distention using a 4-point scale in six segments: cecum, ascending colon, transverse colon, descending colon, sigmoid colon, and rectum. Mean scores of the two radiologists were used to analyze whether any differences existed between techniques in terms of the degree of distention per segment.

Results

Mean distention values for the colonic lumen were better using the automated technique than with the manual technique in both positions (p < 0.05). In segments, distention was significantly better using the automated technique than using the manual technique in the sigmoid and descending colon for prone patients, and in all segments for supine patients.

Conclusions

Automated carbon dioxide insufflation offered significantly improved colorectal distention scores compared to manual room air insufflation.  相似文献   
92.
Purpose  The aim of this study was to assess the variation of probe rotation angles for detecting a single needle using sagittal images of transrectal ultrasonography (TRUS). Materials and methods  A phantom study was performed. One needle was inserted through each of 10 holes of the template, and variations in the probe rotation angles for detecting the needle were measured. Results  The mean variation of probe rotation for detecting a single needle was 17.0° (range 4°–25°). Slightly broader variation was seen for the needle in holes farther away from the probe. Conclusion  Probe rotation angles for detecting a single needle displayed considerable variation. Seed locations recognized on sagittal imaging by TRUS are thus indeterminate, and real-time dose calculations using TRUS for 125I seed implantation should be used with care.  相似文献   
93.
ABSTRACT: OBJECTIVE: This study aimed to investigate clinical features of abdominal emergency surgery in elderly patients, and to determine factors predicting mortality in these patients. METHODS: The study population included 94 patients aged 80 years or older who underwent emergency surgery for acute abdominal diseases between 2000 and 2010. Thirty-six patients (38.3%) were male and fifty-eight patients (61.7%) were female (mean age, 85.6 years). Main outcome measures included background of the patient's physical condition (concomitant medical disease, and performance status), cause of disease, morbidity and mortality, and disease scoring system (APACHE II, and POSSUM). Prognostic factors affecting mortality of the patient were also evaluated by univariate analysis using Fisher's exact test and Mann- Whitney U-test, and by multivariate analysis using multiple logistic regression analysis. RESULTS: Of the 94 patients, 71 (75.5%) had a co-existing medical disease; most patients had hypertension (46.8%). The most frequent surgical indications were acute cholecystitis in 23 patients (24.5%), followed by intestinal obstruction in 18 patients (19.1%). Forty-one patients (43.6%) had complications during hospital stay; the most frequent were surgical site infection (SSI) in 21 patients (22.3%) and pneumonia in 12 patients (12.8%). Fifteen patients died (overall mortality, 16%) within 1 month after operation. The most common causes of death were sepsis related to pan-peritonitis in 5 patients (5.3%), and pneumonia in 4 patients (4.3%). Multiple logistic regression analysis showed that time from onset of symptoms to hospital admission and the POSSUM scoring system could be prognostic factors for mortality. CONCLUSIONS: Mortality in elderly patients who underwent emergency surgery for acute abdominal disease can be predicted using the disease scoring system (POSSUM) and on the basis of delay in hospital admission. Keywords.  相似文献   
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97.
BACKGROUND: The purpose of this study is to evaluate the efficacy of postoperative adjuvant chemotherapy using uracil and tegafur (UFT) for colorectal cancer. METHODS: In a multicenter trial among 43 institutions for patients who underwent curative resection of Dukes' B or C colorectal cancer, a surgery alone group (control group) and a treatment group (UFT group) to which UFT was administered at 400 mg/day for 2 years following surgery were compared. A total of 320 patients were registered between March 1991 and April 1994, and 289 of these patients were analyzed as a full-analysis set. RESULTS: The 5-year disease-free survival rate was 75.7% in the UFT group and 60.1% in the control group, respectively, and the stratified log-rank test showed the statistical significance ( P=0.0081). This difference was marked in rectal cancer ( P=0.0016) and, in particular, the local recurrence was reduced. No significant difference was observed in the 5-year survival rate. The incidence of adverse reactions on administration of UFT was low, and there was no serious adverse reaction. CONCLUSION: It is suggested that the consecutive administration of UFT at 400 mg/day was an effective and highly safe therapeutic method as postoperative adjuvant chemotherapy for rectal cancer.  相似文献   
98.
Gene expression profile of renal proximal tubules regulated by proteinuria   总被引:13,自引:0,他引:13  
BACKGROUND: Proximal tubules activated by reabsorption of protein are thought to play significant roles in the progression of kidney diseases. Thus, identification of genes related to proteinuria should provide insights into the pathological process of tubulointerstitial fibrosis. METHOD: Gene expression profiles were constructed by means of direct sequencing procedures to identify genes induced in the mouse kidney proximal tubules (PT) exposed to proteinuria. RESULTS: By comparing the gene expression of control PT to that of disease model PT, the abundantly expressed genes in control PT were down-regulated presumably because of potentially toxic effects of proteinuria. From the more than 1000 up-regulated genes, an immunity related gene, thymic shared antigen-1 (TSA-1), and a novel gene, GS188, were selected for further characterization. The increased expression of TSA-1, a member of the Ly-6 family, and of GS188 in response to proteinuria was confirmed by Northern analysis, immunohistochemistry, in situ hybridization and laser microdissection along with real-time PCR analysis. Full length cloning of GS188 identified it as a family member of LR8 that was reported to express predominantly in fibroblasts. CONCLUSIONS: The gene expression profiles showed that the expression patterns in PT were changed dramatically by proteinuria. The profiles include novel genes that should be further characterized to aid the understanding of the pathophysiology of progressive kidney diseases.  相似文献   
99.
Background: Vascular smooth muscle tone is regulated by changes in intracellular free Ca2+ concentration ([Ca2+]i) and myofilament Ca2+ sensitivity. These cellular mechanisms could serve as targets for anesthetic agents that alter vasomotor tone. This study tested the hypothesis that propofol increases myofilament Ca2+ sensitivity in pulmonary artery smooth muscle (PASM) via the protein kinase C (PKC) signaling pathway.

Methods: Canine PASM strips were denuded of endothelium, loaded with fura-2/AM, and suspended in modified Krebs- Ringer's buffer at 37[degrees]C for simultaneous measurement of isometric tension and [Ca2+]i.

Results: The KCl (30 mm) induced monotonic increases in [Ca2+]i and tension. Verapamil, an L-type Ca2+ channel blocker, attenuated KCl-induced increases in [Ca2+]i and tension to an equal extent. In contrast, propofol attenuated KCl-induced increases in [Ca2+]i to a greater extent than concomitant changes in tension and caused an upward shift in the peak tension-[Ca2+]i relation. Increasing extracellular Ca2+ in the presence of 30 mm KCl resulted in similar increases in [Ca2+]i in control and propofol-pretreated strips, whereas concomitant increases in tension were greater during propofol administration. The Ca2+ ionophore, ionomycin (0.1 [mu]m), increased [Ca2+]i to approximately 50% of the value induced by 60 mm KCl. Under these conditions, propofol (10, 100 [mu]m) caused increases in tension equivalent to 11 +/- 2 and 28 +/- 3% of the increases in tension in response to 60 mm KCl, whereas [Ca2+]i was slightly decreased. Similar effects were observed in response to the PKC activator, phorbol 12-myristate 13-acetate (PMA, 1 [mu]m). Specific inhibition of PKC with bisindolylmaleimide I before ionomycin administration decreased the propofol- and PMA-induced increases in tension and abolished the propofol- and PMA-induced decreases in [Ca2+]i. Selective inhibition of Ca2+-dependent PKC isoforms with Go 6976 also attenuated propofol-induced increases in tension.  相似文献   

100.
PURPOSE: We compared the usefulness of serum and plasma samples for enhancing the specificity of prostate cancer detection. MATERIALS AND METHODS: We analyzed receiver operating characteristics curves to evaluate prospectively the cancer detection performance of prostate specific antigen (PSA) related parameters derived from serum and plasma samples in 248 and 249 consecutive patients, respectively. RESULTS: Receiver operating characteristics curve analysis showed that PSA density and transition zone PSA density were more powerful predictors of prostate cancer than total or free PSA in the group overall at intermediate serum PSA 2.1 to 10 ng./ml. and in the subgroup with total PSA 4.1 to 10 ng./ml. regardless of digital rectal examination findings. Percent free PSA performed significantly better than total PSA in patients with serum total PSA 4.1 to 10 ng./ml. PSA density, transition zone PSA density and percent free PSA did not differ substantially in patients with serum total PSA 4.1 to 10 ng./ml. However, none of these parameters distinguished patients with prostate cancer from those with benign histology when PSA was in the lower range of 2.1 to 4 ng./ml. The performance of these parameters was worse when plasma sample data were used for calculation. CONCLUSIONS: The performance of percent free PSA appears at least comparable to that of PSA density and transition zone PSA density in patients in this cohort with serum total PSA 4.1 to 10 ng./ml. without regard to digital rectal examination. The poor performance of these parameters in the lower PSA range underscores the need for other parameters to improve the specificity of cancer detection in elderly Japanese males. Continued use of serum samples is justified for measuring PSA related parameters by current assay techniques.  相似文献   
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