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A variety of teeth and bone specimens have been scanned using the constant statistics tomographic scanner developed at the London Hospital Medical College. Each data set has been reconstructed with several Hamming filters, and for a geometric resolution ranging from 20 to 50 micrometers. The reconstructions have been studied using the approximate error formula for the convolution backprojection algorithm. Some inferences are made on the relative structure of the cross sections.  相似文献   
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Purpose: To determine the accuracy of CT and ultrasonography (US) in diagnosing appendicitis in adults stratified to either modality on the basis of body mass index (BMI), a measure of body habitus. Methods: Seventy-two adults with suspected appendicitis and demonstrating atypical clinical features were prospectively stratified to either appendiceal CT or US based on BMI. Patients with BMI < 30 underwent US and with BMI ≥ 30 underwent CT. Outcomes were determined by surgery, the medical record, and clinical follow-up after 3 months. Results: Of the 72 patients enrolled, 30 (24 women and 6 men) underwent CT and 42 (35 women and 7 men) underwent US. The average BMI was 34 ± 4 among patients who had CT and 24 ± 3 among patients who had US. Of the patients who had CT scans, 4 had positive scans for appendicitis and all of these were proven at surgery to have appendicitis. The remaining 26 patients had negative CT scans for appendicitis. Twenty-two of these were subsequently proven either by surgery or clinical follow-up not to have appendicitis, while 4 were lost to follow-up. This corresponds to a sensitivity, specificity, positive predictive value, and negative predictive value of 100 %. Twelve ultrasound examinations were positive for appendicitis. Nine of these patients had appendicitis proven at surgery, 1 had a perforated Meckel's diverticulum, and 2 did not have appendicitis after clinical follow-up. Twenty-seven patients had negative ultrasound exams for appendicitis. However, 6 of these had appendicitis proven at surgery, 17 did not have appendicitis, and 4 were lost to follow-up. Three patients had ultrasound exams that were equivocal for appendicitis; of these, 1 had appendicitis and 2 did not. For US, this corresponds to a sensitivity of 60 %, specificity of 85 %, PPV of 75 %, and NPV of 74 %. Conclusion: This study suggests that CT is an accurate method of evaluating adults with suspected appendicitis who have BMI ≥ 30. Stratifying patients with BMI < 30 to US did not reproduce the results already reported in the literature.  相似文献   
14.
Four Modified Leprosy Elimination Campaigns (MLECs) were conducted in Orissa by March 2003. Their impact on various leprosy indicators was analyzed. More than 70% of the people of the State were examined during these campaigns. The suspect rate decreased from 1.44% to 0.37% towards the fourth MLEC. About 15% of the suspects were clinically confirmed to be having leprosy. The total number of new cases detected during the MLEC years was on the decrease. A marked fall in new case-detection rate was observed during inter-MLEC years. This has resulted in fluctuation in the prevalence rate during the MLEC years, but the overall PR/10,000 population decreased from 12.18 in 1996-97 to 7.3 in March 2003. More than 40% of the total new cases and about 45% of total new child cases for the corresponding year were detected during the MLECs, and the proportion of total new case-detection was as high as 60.8% during the first MLEC. The proportion of female cases detected during succeeding MLECs improved and an almost equal number of female cases were detected during MLECs III and IV. Considering the present leprosy situation in Orissa and the effectiveness of MLECs in case-detection, it was recommended that such campaigns should be undertaken in select high prevalent blocks of the State at regular intervals, along with the strengthening of the integration of NLEP activities into primary health care activities.  相似文献   
15.

Ethnopharmacological relevance

Tinospora cordifolia mentioned as “Rasayana” is extensively used in various herbal preparations for the treatment of different ailments for its general tonic, antiperiodic, antispasmodic, antiinflammatory, antiarthritic, antiallergic and antidiabetic properties. It is extensively used in Ayurveda due to its potential in improving the immune system and the body resistance against infections.

Aim of the study

The aim of the study was to isolate and characterise the immunomodulatory active compounds of Tinospora cordifolia.

Materials and methods

The immunomodulatory activity of different extracts, fractions and isolated compounds in relation to phagocytosis and reactive oxygen species production in human neutrophil cells have been investigated using the PMN phagocytic function studies, NBT, NO and chemiluminescence assay.

Results

The results obtained indicate that ethyl acetate, water fractions and hot water extract exhibited significant immunomodulatory activity with an increase in percentage phagocyctosis. Chromatographic purification of these fraction led to the isolation of a mixture of two compounds 2, 3 isolated for the first time from natural source and five known compounds 1, 47 which were characterized as 11-hydroxymustakone (2), N-methyl-2-pyrrolidone (3), N-formylannonain (1), cordifolioside A (4), magnoflorine (5), tinocordiside (6), syringin (7) by nuclear magnetic resonance (NMR) and mass spectrometry (MS) and comparing the spectral data with reported one. Cordifolioside A and syringin have been reported to possess immunomodulatory activity. Other five compounds showed significant enhancement in phagocytic activity and increase in nitric oxide and reactive oxygen species generation at concentration 0.1–2.5 μg/ml.

Conclusions

Seven immunomodulatory active compounds belonging to different classes have been isolated and characterised indicating that the immunomodulatory activity of Tinospora cordifolia may be attributed to the synergistic effect of group of compounds.  相似文献   
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Bone pain, especially back pain, is a common presenting feature of myeloma patients. We report three multiple myeloma patients with exacerbations of back pain and referred shoulder pain resulting from vertebral infections. Two patients were treated with surgery, and one patient had computerized tomography-guided percutaneous needle aspiration for diagnostic purposes. All three patients received a prolonged course of antibiotics. Vertebral infection resolved with this treatment in all three patients without any recurrence. Previous dexamethasone therapy, together with an episode of bacteraemia, appears to be a predisposing factor for vertebral infection. Magnetic resonance imaging enabled the diagnosis in all three patients.  相似文献   
19.
Various anomalies in the size, shape, number, structure and eruption of the teeth are often observed clinical conditions. Supernumerary teeth can be found in almost any region of the dental arch, and most of the times they are asymptomatic, and are routinely found during radiographic evaluation. The most common cause of impacted maxillary incisors is the presence of the supernumerary teeth. This paper describes a case of multiple supernumerary teeth associated with an impacted permanent maxillary central incisor in an 11-year old child along with its surgical and orthodontic management.  相似文献   
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