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21.
Background Immune dysregulation has been shown to be one of the major aspects of the yet unknown pathogenesis of Behçet's disease. Interleukin-8 (IL-8), a major chemokine with pivotal effects concerning leukocytes and endothelial cells, has been found to be elevated in patients with Behçet's disease. Aim To evaluate the significance of elevated levels of IL-8 with respect to the activity of Behçet's disease. Methods Sixty-seven consecutive patients with Behçet's disease (37 males, 30 females; 32.5 ± 9.3 years) were enrolled in our study. The number of active clinical manifestations at the time of serum sampling was recorded. The degree of association between disease activity and IL-8, C-reactive protein, and erythrocyte sedimentation rate was assessed. Results Serum levels of IL-8 increased as the number of clinically involved organs increased (P < 0.05). C-reactive protein and the erythrocyte sedimentation rate showed no correlation with disease activity. Conclusions Our study confirms that the IL-8 level is a more sensitive marker of disease activity than the erythrocyte sedimentation rate and C-reactive protein. It may be assumed that IL-8 plays an important role in the pathophysiology of Behçet's disease.  相似文献   
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BACKGROUND: Cardiac gating is not routinely used in cardiac positron emission tomography (PET). The aim of this study was to determine the feasibility of assessing regional wall motion, ejection fraction (EF), cardiac volumes, and mass with nitrogen-13 ammonia (N-13 ammonia) at the time of PET myocardial perfusion imaging. METHODS: We studied 12 healthy volunteers (mean age, 28 +/- 8 years) and 53 patients with documented coronary artery disease (CAD) (mean age, 59 +/- 11 years). All subjects received a single administration of approximately 600 MBq (16 mCi) of N-13 ammonia intravenously. A 6-minute dynamic scan was performed for quantitative assessment of myocardial perfusion at rest, followed by a separate, 13-minute static scan acquired in the gated mode (8 equal bins). Gated data was imported into the Emory Toolbox. Wall motion was evaluated by dividing the myocardium into 9 anatomic regions graded semiquantitatively. RESULTS: Healthy volunteers had a normal EF (61 +/- 6), end systolic volume (ESV) (37 +/- 15 mL), end diastolic volume (EDV) (89 +/- 25 mL), and cardiac mass (116 +/- 18 g). In contrast, patients with CAD showed reduced EF (32 +/- 13%) and increased ESV (129 +/- 56 mL), EDV (188 +/- 68 mL), and cardiac mass (173 +/- 45 g) (P < 0.001 for each). In patients with CAD, EF measured by gated PET correlated significantly to independent measurements of EF (P < 0.001). CONCLUSIONS: Gating of cardiac perfusion images obtained after administration of N-13 ammonia is feasible and appears to be an accurate means of evaluating regional and global cardiac function. Gating can provide important additional diagnostic and prognostic information.  相似文献   
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Case 55: fetus in fetu   总被引:2,自引:0,他引:2  
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Despite sufficient knowledge of good oral hygiene habits, dental students still suffer from oral health problems owing to dietary habits, obesity, and a sedentary lifestyle. This cross-sectional study was conducted to evaluate an association of BMI (body mass index), diet, physical activity, and oral hygiene practices with DMFT (decayed, missing, and filled teeth) of male dental students and interns at King Faisal University, Saudi Arabia, from August to September 2020. One hundred and eighty-five male participants completed the study questionnaire. The questionnaire consisted of sociodemographic information and nineteen close-ended questions about current diet, physical activity, and oral hygiene practices. Students’ height (cm) and weight (kg) were measured to calculate BMI. The principal investigator performed the oral clinical examinations for the DMFT status in the dental clinic. The chi-square test was used for the dichotomous variables and a t-test was used for the continuous variables. Linear and multinomial logistic regression were performed to detect the significant predictors of the DMFT score. The mean age of participants was 22.29 ± 2.13 years, and the BMI was 24.94 ± 3.36 (Kg/m2). Parents’ higher education and income levels were significantly (p < 0.001) associated with a higher BMI. Most dietary variables, especially sugar products, and low physical activity, were significantly (<0.047) associated with higher BMI. All oral hygiene practices, except miswak and mouthwash, were significantly (<0.003) associated with higher BMI. Decayed and missing teeth were significantly (<0.001) higher in the overweight and obese. A simple linear regression analysis demonstrated association between BMI and decayed teeth, with an R = 0.35 (<0.001); BMI and missing teeth had an R = 0.12 (p = 0.867); BMI and filled teeth had an R = 0.15 (p = 0.033), and BMI with DMFT had an R = 0.33 ((<0.001). This study demonstrated a strong significant association of the decayed and missing teeth with higher BMI levels. In addition, BMI was significantly associated with diet and physical activity, despite acceptable oral hygiene practices.  相似文献   
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A murine monoclonal antibody directed against carcinoembryonic antigen (CEA) was labeled with indium-111 (111In) by means of a benzylisothiocyanate derivative of diethylenetriamine penta-acetic acid (DTPA) and used for clinical radioimmunodetection studies. Twenty-one patients having a history of surgically resected colorectal cancer and rising serum CEA levels suggestive of tumor recurrence were studied. Patients were infused over 20 minutes with 5, 10, or 20 mg of the monoclonal antibody labeled with 5 mCi of 111In. The mean radiochemical purity was greater than 96%. No toxicity was seen. The stability of the radiolabel on antibody in patient serum was demonstrated by high-performance liquid chromatography (HPLC), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) with autoradiography, and immunoprecipitation for up to 96 hours after infusion. Tumor sites were identified in 20 of 21 patients. Sites of antibody accumulation in 20 patients were confirmed as tumor either by resection at laparotomy (16 patients) or fine-needle biopsy (four patients). Nine patients who had the identified lesion resected or irradiated showed return of the serum CEA antigen level to normal or near normal values. In the absence of high levels of circulating CEA (greater than 500 ng/mL), the disappearance of radioactivity from patient serum demonstrated first order elimination kinetics, with a mean half-life of 38 hours. The serum half-life was not affected by the dose of antibody administered or by serum CEA titers below 500 ng/mL. Despite a mean liver uptake of 18% injected dose (ID) 24 hours after administration, hepatic metastases were easily visualized as areas of increased uptake of radioactivity. Radioimmunodetection of recurrent colorectal cancer, not detected by computed tomographic (CT) scans, appears achievable with this agent. This may allow successful clinical intervention in selected patients.  相似文献   
27.
Escherichia coli is considered to be the main causative agent of urinary tract infections (UTIs). The primary objective of this study was to investigate the spectrum of five virulence factors among drug-resistant clinical E. coli isolates associated with pyelonephritis and cystitis. A total of 101 samples were positive for E. coli (42 from pyelonephritis cases and 59 from cystitis cases) out of 457 urine samples of patients. Among toxins, haemolysin and secreted autotransporter toxin are found more frequently in isolates causing pyelonephritis (p < 0.020) than cystitis (p < 0.083). The frequent occurrence of P-pili, S-fimbria and protein involved in intestinal colonisation was noted among E. coli isolates associated with pyelonephritis. Overall, the study suggests that clinical isolates associated with pyelonephritis are more virulent than those associated with cystitis and diversified association with various antimicrobial resistance phenotypes was noted.  相似文献   
28.
Seven patients with colorectal adenocarcinoma and one with squamous cell carcinoma of anorectal region were infused preoperatively with iododeoxyuridine (IUdR) and bromodeoxyuridine (BrdU) in sequence (100 mg/m2 x 1 hr each with 1-hr interval in between) to label S-phase cells. The tumor biopsy specimens were embedded in glycol-methacrylate and 2-microns thick sections were treated with two monoclonal antibodies which permitted the identification of cells which incorporated IUdR only, BrdU only, both IUdR and BrdU, or neither IUdR or BrdU. The labeling index of tumors varied from 17.3 to 35.6% (mean = 25.78 +/- 6.162), duration of S-phase ranged from 14.0 to 23.9 hr (mean = 18.73 +/- 3.712), and total cell cycle time ranged from 39.4 to 123.4 hr (mean = 76.78 +/- 24.165). The architecture of the tumor was well preserved and a variable number of DNA synthesizing mononuclear cells were identified within and around the tumor. Image analysis of Feulgen-stained smears of the tumors was done to measure the DNA content of seven tumor samples. Each tumor was found to be hyperdiploid with multiple modal values. The studies described here demonstrate the feasibility of performing cell cycle kinetic measurements on gastrointestinal tumors which have been labeled in vivo. The ability to perform these measurements on tumor biopsies allows the avoidance of artifacts introduced when solid tumors are disaggregated in vitro for study.  相似文献   
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Emerging infectious diseases remain among the leading causes of global mortality. Traditional laboratory diagnostic approaches designed to detect and track infectious disease agents provide a framework for surveillance of bio threats. However, surveillance and outbreak investigations using such time-consuming approaches for early detection of pathogens remain the major pitfall. Hence, reasonable real-time surveillance systems to anticipate threats to public health and environment are critical for identifying specific aetiologies and preventing the global spread of infectious disease. The current review discusses the growing need for monitoring and surveillance of pathogens with the same zeal and approach as adopted by microbial forensics laboratories, and further strengthening it by integrating with the innovative nanotechnology for rapid detection of microbial pathogens. Such innovative diagnostics platforms will help to track pathogens from high risk areas and environment by pre-emptive approach that will minimize damages. The various scenarios with the examples are discussed where the high risk associated human pathogens in particular were successfully detected using various nanotechnology approaches with potential future prospects in the field of microbial forensics.  相似文献   
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