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51.
A large area and highly sensitive thermoluminescent (TL) sheet film was used for two-dimensional dose distribution measurements at millimetre distances from a 103Pd interstitial brachytherapy source. The TL film is made of Teflon homogeneously mixed with small particles of thermoluminescent material (BaSO4: Eu doped). This TL sheet (5 cm x 5 cm) was used to determine the relative dosimetric characteristics (i.e., radial dose function, 2D and 1D anisotropy functions, as defined by the updated AAPM Task Group No 43 report) of the model 200 103Pd source that emits low energy photons (21 keV). The two-dimensional dosimetry data were obtained for distances from the source surface to 15 mm. The radial dose function measured with the TL sheet is in reasonable agreement within 11% with the values recommended in the updated AAPM TG-43 report. All the measured 2D dose distributions showed limited symmetry about the source axes. The differences between the 1D anisotropy function values measured with the TL sheet and the data recommended in the updated AAPM TG-43 report were 10% at 5 mm and 7.5% at 10 mm, respectively, for the model 200 103Pd seed. Our experiments have demonstrated that it is feasible to use the TL sheet as a dosimeter in the determination of the dosimetric characteristics in the immediate vicinity of interstitial brachytherapy sources emitting low energy photons. 相似文献
52.
S Sridhara B P Singh N Arora J Verma S V Gangal 《Asian Pacific journal of allergy and immunology / launched by the Allergy and Immunology Society of Thailand》1992,10(1):33-38
The stability of three allergens common in tropical countries was evaluated under different storage conditions. Prosopis juliflora (PJ), Rhizopus nigricans (RN), and wheat dust (WD), were taken as representatives of various groups of allergens viz, pollen, fungi and dust. The extracts were stored in buffer containing phenol (0.4%) or glycerol (50%) at temperatures ranging from 4-55 degrees C for 15 to 60 days. Protein content of PJ extract was reduced remarkably when it was stored at 40 degrees C for 45 days. Thin layer isoelectric focusing and rocket immunoelectrophoresis of PJ showed that certain antigenic proteins degrade rapidly even at 25 degrees C as early as day 15. However, two to three proteins of PJ remain stable at a higher temperature (40 degrees C) for two months. Relative radioallergosorbent test (RAST) inhibition showed substantial loss of allergenic activity in all the three extracts, when stored at higher temperatures (25-55 degrees C) even for short durations, i.e., 15 days. Extracts (PJ and RN) containing 50% glycerol were found to be stable, retaining more than 50% activity, even when stored at 55 degrees C for 40 days, while extracts without glycerol lost more than 75% of their allergenic activity. However, addition of glycerol did not change the stability of wheat dust allergenic extract. The present findings indicate that allergenic extracts behave differently when stored. Hence, the stability of each extract should be determined individually. 相似文献
53.
Szabo Gyongyi Mandrekar Pranoti Verma Bikash Isaac Ann Catalano Donna 《Journal of clinical immunology》1994,14(6):340-352
The hypothesis that acute ethanol uptake plus trauma can synergize to increase immunosuppression was tested. We found that, unlike non-alcohol-exposed patients, patients with acute alcohol use prior to trauma have a transient decrease in monocyte tumor necrosis factor (TNF) production during the very early postinjury (0–3 days) period. However, TNF production by these alcoholexposed patients' monocytes (MØ) became hyperelevated late postinjury (>9 days). Consequently, these massively elevated MØ TNF levels can contribute to posttrauma immunosuppression after acute alcohol use. We also demonstrate that normal monocyte activation with the superantigen,Staphylococcus enterotoxin B (SEB), results in a preferential induction of cellassociated MØ TNF production, described as characteristic of immunosuppressed trauma patients. Acutein vitro ethanol treatment down-regulated the elevated TNF production by trauma patients' MØ after either SEB, muramyl-dipeptide (MDP), interferon- plus MDP, or lipopolysaccharide (LPS) stimulation. Both SEB- and LPS-induced TNF mRNA induction was inhibited by acute alcohol treatment in normal MØ, indicating that ethanol can regulate cytokine gene expression. An additional immunosuppressive effect of acute ethanol's stimulation was suggested by its induction of elevated transforming growth factor production in trauma patients' activated MØ. 相似文献
54.
Eight patients with sickle cell anemia (SS hemoglobin) were found to have decreased plasma levels of prekallikrein compared to normal control subjects or patients with other types of anemia. The prekallikrein levels in the patients with sickle cell anemia were found to decrease further during a sickle cell crisis. These results suggest that components of the kallikrein-kinin system are profoundly affected in patients with sickle cell anemia, and during crises may play a role in the clinical presentation of patients. 相似文献
55.
Macrocarposide, a new isoflavanone c-glucoside from Pterocarpus macrocarpus heart wood 总被引:1,自引:0,他引:1
Macrocarposide has been isolated for the first time as a natural product from the heartwood of PTEROCARPUS MACROCARPUS along with some known compounds. Based on its spectral and chemical evidence, it has been assigned the structure dalbergioidin-6- C-glucoside ( 1). 相似文献
56.
Modulation of mouse skin tumor promotion by dietary 13-cis-retinoic acid and {alpha}-difluoromethylornithine 总被引:1,自引:1,他引:0
The effects of dietary supplementation of 13-cis-retinoic acid(13-cis-RA) and -difluoromethylornithine (DFMO) in the drinkingwater on 12-O-tetradecanoylphorbol-13-acetate (TPA)-promotedskin tumor formation was determined. Administration of 13-cis-RAin the diet and DFMO in the drinking water was started 1 weekand 2 days before the first TPA application to the dimethylbenz[a]anthracene-initiatedskin of either female CD-I or SENCAR mice, respectively. Dietary13-cis-RA failed to inhibit both the tumor yield and the incidence;papillomas per mouse at 0, 5, 50, 100 and 200 mg/kg diet 13-cis-RAdoses were 25, 30, 22, 28 and 25 respectively at 18 weeks ofpromotion treatment and at all doses 100% of the mice bore papillomas.However, dietary 13-cis-RA dramatically reduced the size ofskin tumor promoted with TPA. 13-cis-RA at doses of 5, 50, 100and 200 mg/kg diet inhibited skin papillomas (> 4 mm diameter)per mouse by 28, 55, 76 and 93%, respectively. Retinoid treatmentdid not affect body weight gains and the survival was more than80% in all groups. In accord with our previous findings, DFMOwhen given in drinking water, was a very effective inhibitorof mouse skin tumor promotion by TPA; DFMO at 0.25% concentrationinhibited the number of papillomas by 50%. Inhibition of skintumor promotion by combined treatments with dietary 13-cis-RA(100 mg/kg) and DFMO (0.25%) in the drinking water was possiblyadditive. The retinoid and DFMO preclude TPA-increased ornithinedecarboxylase (ODC) activity and the accumulation of putrescineby differential effects on ODC, an enzyme associated with skintumor promotion by TPA. 相似文献
57.
Pulmonary tuberculosis among contacts of patients with tuberculosis in an urban Indian population. 总被引:1,自引:0,他引:1
R A Kumar M Saran B L Verma R N Srivastava 《Journal of epidemiology and community health》1984,38(3):253-258
The study was conducted among 1810 contacts of 50 index "cases"/"suspects" of pulmonary tuberculosis including 312 household and 1498 neighbourhood contacts in the Jhansi city of Uttar Pradesh. The overall prevalence of radiologically active and bacteriologically confirmed tuberculosis was 2.9% and 1.1%. The prevalence rates of radiologically active and bacteriologically confirmed disease, although comparatively high in both the contact groups, were significantly higher in household (5.4% and 2.6%) than in neighbourhood contacts (2.3% and 0.8%). Significant differences in distribution of secondary cases among clusters were observed. Although higher prevalence rates were found in contacts of sputum positive source than in contacts of sputum negative source in both the contact groups, the statistical difference was observed to be insignificant. Case yield among contact symptomatics was 80.0% (30.8% cases and 49.2% suspects). 相似文献
58.
Seventeen children presenting with leucocoria were subjected to complete investigations. Careful A and B mode ultrasonography allowed us to make the correct diagnosis of retinoblastoma in 11 eyes of 9 patients, which was confirmed by histopathology or by response to radiotherapy. The diagnosis of retinoblastoma was not missed ultrasonographically in any of the eyes studied. The "V/W" configuration and absence of vascular pulsations on A mode; the "mixed" pattern and absence of choroidal excavation and orbital shadowing on B mode were found to be essential echographic features in characterizing the tumor and in differentiating it from other conditions including vitreous hemorrhage. The ultrasonographic features of early extraocular extension of retinoblastoma are discussed. Careful ultrasonic evaluation of leucocoria would seem to be invaluable in obviating the possibility of misdiagnosis in such problematic cases. 相似文献
59.
Male pseudohermaphrodite with persistent Mullerian duct: A radiologist’s and patient’s dilemma alike
This case study highlights that how a disorder of sexual development when goes unnoticed at birth and unreported during childhood or adolescence can present with major problems and even complications in adulthood. Since our patient was young and in a childbearing age, he presented with bilateral undescended testes and orgasmic anejaculation when he first came to the hospital. Subsequently, having a normal 46XY karyotype but remnants of persistent Mullerian duct made him little confused about his identity. After giving him the confidence, that he was still a male and could lead the life he did previously, the explanation about future risk of malignancy in the intra-abdominal testes was another difficult task. Early detection and management of male pseudohermaphroditism with persistent Mullerian duct requires a co-ordinated approach of a team of endocrinologist, physician, surgeon and radiologist. Integrated imaging in the form of ultrasound, genitography and MRI is important in demonstrating the anatomy, classification, possible effects or congenital malformations in other organs, warning patients of any risk of neoplasia and guiding the clinician to plan other investigations, hormonal replacement or reconstruction surgery if required. Such a systemic approach that allays anxiety and gives psychological relief to the patient should be taken as it can deeply change the life of a person and their family. 相似文献
60.