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1.
Diagnosis of gastric carcinoma by classification on feature projections   总被引:1,自引:0,他引:1  
A new classification algorithm, called benefit maximizing classifier on feature projections (BCFP), is developed and applied to the problem of diagnosis of gastric carcinoma. The domain contains records of patients with known diagnosis through gastroscopy results. Given a training set of such records, the BCFP classifier learns how to differentiate a new case in the domain. BCFP represents a concept in the form of feature projections on each feature dimension separately. Classification in the BCFP algorithm is based on a voting among the individual predictions made on each feature. In the gastric carcinoma domain, a lesion can be an indicator of one of nine different levels of gastric carcinoma, from early to late stages. The benefit of correct classification of early levels is much more than that of late cases. Also, the costs of wrong classifications are not symmetric. In the training phase, the BCFP algorithm learns classification rules that maximize the benefit of classification. In the querying phase, using these rules, the BCFP algorithm tries to make a prediction maximizing the benefit. A genetic algorithm is applied to select the relevant features. The performance of the BCFP algorithm is evaluated in terms of accuracy and running time. The rules induced are verified by experts of the domain.  相似文献   
2.
OBJECTIVE: To determine whether there is a significance of the choice of prone versus supine position in the treatment of proximal ureter stones with extracorporeal shock wave lithothripsy (ESWL). METHODS: Ninety-six patients with proximal ureter stones underwent ESWL. The procedure was performed in the supine position in 48 of them (group 1) and in the prone position in the other 48 patients (group 2). Stone-free rates, repeat ESWL rates, shocks per patient and shocks per session were compared in both groups. RESULTS: The mean session number per patients was 1.64+/-0.75 in group 1 and 1. 33+/-0.59 in group 2 (p = 0.224). The stone-free rates 3 months after ESWL were 88.3% in group 1 and 90.6% in group 2. The difference between the results was statistically insignificant (p<0.05). Therefore, these two parameters were similar in both groups. On the other hand, the number of shocks per session was 4,863.54+/-2, 114.85 in group 1 and 3,704.16+/-1,726.75 in group 2. This difference was statistically significant (p = 0.011). The patients tolerated the supine position better in general. Patients in the prone position experienced discomfort on inspiration and expiration and pain localized to the lumbar vertebrae. CONCLUSION: These results suggest that the supine position decreases the number of shocks per session in the treatment of proximal ureter stones with ESWL and this will be cost-effective.  相似文献   
3.
Adenosine deaminase (ADA), 5-Nucleotidase (5NT), Xanthine oxidase (XO), Cu-Zn Superoxide dismutase (SOD) and Catalase (CAT) activities were determined in gastric juices from patients with gastric cancer, ulcer, gastritis and from healthy subjects. Enzyme activities were given as units per ml gastric juice and units per mg protein in gastric juice. ADA, 5NT and XO activities were found lower and protein concentrations were found higher in the cancer group than controls. There was however no significant difference between Cu-Zn SOD activities of the cancer and control groups. In all groups including control one, we could not find catalase activities in most of the samples. On the other hand, ADA, 5NT activities and protein concentrations in the gastric juice were lower in the gastritis group than control group. In the ulcer group, we found higher Cu-Zn SOD and XO activities and lower 5NT activity and protein concentrations compared with control values. In an attempt to establish statistical correlations between mean enzyme activities, pH and protein concentrations in the gastric juices of the groups, we found noticeable intra and inter-correlations, which indicated possible relations between DNA and free radical metabolizing enzymes.  相似文献   
4.
In this multicenter, retrospective study, we evaluated the efficacy and safety of biologic therapies, including anti-TNFs, in secondary (AA) amyloidosis patients with ankylosing spondylitis (AS) and rheumatoid arthritis (RA). In addition, the frequency of secondary amyloidosis in RA and AS patients in a single center was estimated. Fifty-one AS (39M, 12F, mean age: 46.7) and 30 RA patients (11M, 19F, mean age: 51.7) with AA amyloidosis from 16 different centers in Turkey were included. Clinical and demographical features of patients were obtained from medical charts. A composite response index (CRI) to biologic therapy—based on creatinine level, proteinuria and disease activity—was used to evaluate the efficacy of treatment. The mean annual incidence of AA amyloidosis in RA and AS patients was 0.23 and 0.42/1000 patients/year, respectively. The point prevalence in RA and AS groups was 4.59 and 7.58/1000, respectively. In RA group with AA amyloidosis, effective response was obtained in 52.2 % of patients according to CRI. RA patients with RF positivity and more initial disease activity tended to have higher response rates to therapy (p values, 0.069 and 0.056). After biologic therapy (median 17 months), two RA patients died and two developed tuberculosis. In AS group, 45.7 % of patients fulfilled the criteria of good response according to CRI. AS patients with higher CRP levels at the time of AA diagnosis and at the beginning of anti-TNF therapy had higher response rates (p values, 0.011 and 0.017). During follow-up after anti-TNF therapy (median 38 months), one patient died and tuberculosis developed in two patients. Biologic therapy seems to be effective in at least half of RA and AS patients with AA amyloidosis. Tuberculosis was the most important safety concern.  相似文献   
5.
In the literature, there have been no studies showing clear results on how radio‐contrast pharmaceuticals would affect intact disc tissue cells. In this context, it was aimed to evaluate the effects of iopromide and gadoxetic acid, frequently used in the discography, on intact lumbar disc tissue in pharmaco‐molecular and histopathological level. Primary cell cultures were prepared from the healthy disc tissue of the patients operated in the neurosurgery clinic. Except for the control group, the cultures were incubated with the indicated radio‐contrast agents. Cell viability, toxicity and proliferation indices were tested at specific time intervals. The cell viability was quantitatively analysed. It was also visually rechecked under a fluorescence microscope with acridine orange/propidium iodide staining. Simultaneously, cell surface morphology was analysed with an inverted light microscope, while haematoxylin and eosin (H&E) staining methodology was used in the histopathological evaluations. The obtained data were evaluated statistically. Unlike the literature, iopromide or gadoxetic acid did not have any adverse effects on the cell viability, proliferation and toxicity (P < 0.05). Although this study reveals that radio‐contrast pharmaceuticals used in the discography, often used in neurosurgical practice, can be safely used, it should be remembered that this study was performed in an in vitro environment.  相似文献   
6.

Background

Only limited attention has been paid to the anatomy and clinical importance of the falcine venous plexus. The aim of this study was to evaluate the falcine venous plexus anatomically using scanning electron microscopy (SEM), and to provide guidance for neurosurgical approaches.

Methods

Latex or ink was injected into the superior and inferior sagittal sinus. The falcine venous plexus lying within the connective tissue of the falx cerebri was observed by dividing the falx into thirds (anterior, middle and posterior). Further, the SEM appearance of the falcine venous plexus was evaluated.

Results

The anterior third of the falx cerebri consisted of small diameter falcine venous vessels. These vessels were localized close to either the superior or inferior sagittal sinus, and none extended as far as mid-falx cerebri levels in any of the 16 cases. They communicated with either superior or inferior sagittal sinuses, but not with both of these sinuses. In the middle third of the falx cerebri, the majority of the vessels of the falcine venous plexus had larger diameter compared to those of the anterior third. These vessels extended the length of the falx cerebri levels. They communicated with both superior and inferior sagittal sinuses. In the posterior third of the falx cerebri, the vessels of the falcine venous plexuses had the largest diameter and were located at the junction of the inferior sagittal sinus and the straight sinus. They were localized at the lower two-thirds of the falx cerebri. In all cases, the dense venous networks communicated with the inferior sagittal sinus but not with the superior sagittal sinus. The falcine venous plexus observed in the posterior third of the falx cerebri was denser than in the anterior and middle portions. The SEM revealed small vessels whose diameter ranged between 42 and 138 μm. The vessels of the falcine venous plexus in the anterior third had a mean diameter of 0.42?±?0.1 mm, in the middle third a mean diameter of 0.87?±?0.17 mm, and in the posterior third, 1.38?±?0.21 mm.

Conclusion

The falcine venous plexus is a network of venous channels that exists within the connective tissue of the falx; the sizes and patterns of communication of these structures showed regional differences. Neurosurgeons should be aware of the regional differences when making an incision or puncturing the falx during a surgical approach.  相似文献   
7.
8.
Dagli N  Yavuzkir M  Karaca I 《Inflammation》2007,30(6):230-235
Objective Coronary artery disease (CAD) is presently the major cause of mortality and morbidity. Anti-hyperlipidemic treatment is one of the main treatment steps in the management of CAD. Statins are the cornerstones in this treatment. Ezetimibe can be reliably used, when statins prove ineffective in treatment, or to reduce their side effects. In the present study we examined the effects of high-dose pravastatin (40 mg) and low-dose pravastatin (10 mg) + ezetimibe (10 mg) combination therapy on lipid and glucose mechanism, as well as inflammation. Methods This study registered 100 cases. Of the cases, 50 [57.1 ± 11.1 years (24 (48%) females and 26 (52%) males)] were administered 40 mg/day pravastatin (group 1) and 50 [53.2 ± 12.2 years (27 (54%) females and 23 (46%) males)] were administered 10 mg pravastatin + 10 mg ezetimibe (group 2). Results In group 1, total cholesterol fell from 231.1 ± 83.5 mg/dl to 211.3 ± 37.2 mg/dl (p = 0.03), triglyceride from 243.5 ± 96.8 mg/dl to 190.9 ± 55.2 mg/dl (p = 0.003), and LDL cholesterol from 165.7 ± 29.7 mg/dl to 133.4 ± 26.6 mg/dl (p = 0.02). In group 2, total cholesterol dropped from 250.9 ± 51.8 mg/dl to 187.9 ± 34.9 mg/dl (p = 0.001), triglyceride from 270.3 ± 158.9 mg/dl to 154.6 ± 60.7 mg/dl (p = 0.001), and LDL cholesterol from 158.1 ± 47.5 mg/dl to 116.9 ± 26.4 mg/dl (p = 0.001). Insulin resistance decreased from 4.05 ± 2.31 to 3.16 ± 1.90 (p = 0.07) in group 1 and from 2.96 ± 1.50 to 2.05 ± 0.55 (p = 0.009) in group 2. High sensitive C-reactive protein fell from 6.69 ± 6.11 mg/l to 3.02 ± 1.70 mg/l (p = 0.01) in group 1 and from 6.36 ± 2.06 mg/l to 2.68 ± 1.69 mg/l (p = 0.001) in group 2. Conclusion Both therapy regimes are effective. However, we found that low-dose pravastatin and ezetimibe combination therapy is more effective than high-dose pravastatin therapy on lipid metabolism, glucose metabolism and inflammation.  相似文献   
9.
Circulating leptin shows a pulsatile secretory pattern along with a nocturnal rise. We have previously shown that circulating leptin concentrations are high in males with untreated idiopathic hypogonadotropic hypogonadism (IHH). However, circadian leptin secretion in IHH before and after gonadotropin treatment is not known. Thus, we studied 14 adult males with IHH who had no history of previous hormonal therapy, and 12 age- and body mass index-matched healthy men. Plasma leptin concentrations were measured with 1-h intervals for 24 h before and 6 months after gonadotropin treatment. The 24-h mean leptin concentration showed a significant decrease, from 11.78 +/- 1.908 microg/liter at baseline to 10.85 +/- 1.939 microg/liter after 6 months of therapy (z = 3.107; P = 0.002). Before and after treatment, 24-h mean leptin concentrations were also significantly higher in the patient group when compared with controls (4.275 +/- 0.711 microg/liter) (z = 5.938; P = 0.0001). Hourly leptin levels demonstrated a diurnal pattern in hypogonadal patients, a surge in the midday, and a peak just after midnight, and this pattern did not differ before and after treatment. We observed a similar diurnal pattern in the control subjects too. Leptin levels were negatively and significantly correlated with free testosterone and total testosterone levels both before (r = -0.656, P = 0.011; and r = -0.639, P = 0.014, respectively) and after (r = -0.537, P = 0.048; and r = -0.563, P = 0.036, respectively) gonadotropin administration. Our observations suggest that the diurnal rhythm of leptin is intact in males with IHH, and short-term gonadotropin treatment does not effect its diurnal rhythm. Moreover, testosterone produced under the influence of the gonadotropin treatment led to decreases in the leptin levels.  相似文献   
10.
BACKGROUND: Receptor-binding cancer antigen expressed on SiSo cells (RCAS1) is a novel tumour marker that has been described in various kinds of cancer. The majority of observations include immunohistochemical studies; however, there are not enough data about the utility of this antigen as a serum tumour marker and its tumour specificity. AIM: To measure the serum levels of RCAS1 in patients with gastrointestinal (GI) tract cancers and compare them with other GI tract tumour markers. PATIENTS AND METHODS: Sera collected from patients with GI cancers (14 esophagus, 32 gastric and 36 colon) and from healthy volunteers (30 individuals) were analyzed for RCAS1 and compared with carcinoembryonic antigen (CEA) and cancer antigen 19-9. The relationship between serum RCAS1, tumour stage and tumour grade was also evaluated. RESULTS: Mean serum RCAS1 level was higher in patients with GI tract cancers compared with the control group (P=0.001). Among GI tract cancers, RCAS1 had lowest and highest sensitivity for esophagus and colon cancer diagnosis, respectively. Serum RCAS1 had a higher sensitivity for malignancy, except in the colon, and lower specificity in all groups compared with CEA. In comparison with cancer antigen 19-9, serum RCAS1 was more sensitive but less specific for all GI cancer groups. Mean serum RCAS1 levels were not statistically significant among histopathological tumour types (P>0.05). Although serum RCAS1 levels were significantly higher in cases with lymph node involvement compared with lymph node-negative cases (P=0.009), there was no difference between cases with and without serosal involvement, vascular invasion and distant metastasis; no correlation was found between tumour size and RCAS1 levels. CONCLUSIONS: RCAS1 may be used and combined with CEA as a tumour marker in GI tract cancers.  相似文献   
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