ABSTRACT
BEAMnrc was used to derive the X-ray spectra, from which HVL and homogeneity coefficient were determined, for different kVp and filtration settings. Except for the peak at 61 keV, the spectra are in good agreement with the IPEM report 78 data for the case of filtered beams, whereas the unfiltered beams exhibit softer spectra. Although the current attenuation data deviates from the IPEM 78 data by ~±0.5%, this has negligible effects on the calculated HVL values.
Subject(s)
Radiation Dosage , X-Rays/adverse effects , Computer Simulation , Filtration , Humans , Monte Carlo Method , Radiation Protection/methods , UncertaintyABSTRACT
In a densely populated urban area of Karachi, Pakistan, a questionnaire survey was made of the knowledge and practices of 120 private general practitioners about the diagnosis and treatment of tuberculosis (TB). The majority knew that cough, fever and weight loss were the main symptoms of TB, but less than half knew that blood in sputum, poor appetite and chest pain were associated with the disease. Only 58.3% of physicians used sputum microscopy for diagnosing TB and 35.0% used it as a follow-up test. Only 41.7% treated TB patients themselves, the remaining referring their patients to specialists. Around 73.3% of the doctors were aware of the 4 first-line anti-TB drugs. Efforts to improve the knowledge of private practitioners, and strategies to enhance public-private collaboration forTB control in urban areas are urgently required.
Subject(s)
Physicians, Family , Practice Patterns, Physicians'/organization & administration , Private Practice/organization & administration , Tuberculosis, Pulmonary , Urban Health Services/organization & administration , Anorexia/microbiology , Antitubercular Agents/therapeutic use , Attitude of Health Personnel , Chest Pain/microbiology , Clinical Competence/standards , Cough/microbiology , Fever/microbiology , Health Knowledge, Attitudes, Practice , Health Services Research , Hemoptysis/microbiology , Humans , Needs Assessment , Pakistan , Physicians, Family/education , Physicians, Family/organization & administration , Physicians, Family/psychology , Referral and Consultation/organization & administration , Surveys and Questionnaires , Tuberculosis, Pulmonary/complications , Tuberculosis, Pulmonary/diagnosis , Tuberculosis, Pulmonary/drug therapy , Weight LossABSTRACT
In a densely populated urban area of Karachi, Pakistan, a questionnaire survey was made of the knowledge and practices of 120 private general practitioners about the diagnosis and treatment of tuberculosis [TB]. The majority knew that cough, fever and weight loss were the main symptoms of TB, but less than half knew that blood in sputum, poor appetite and chest pain were associated with the disease. Only 58.3% of physicians used sputum microscopy for diagnosing TB and 35.0% used it as a follow-up test. Only 41.7% treated TB patients themselves, the remaining referring their patients to specialists. Around 73.3% of the doctors were aware of the 4 first-line anti-TB drugs. Efforts to improve the knowledge of private practitioners, and strategies to enhance public-private collaboration for TB control in urban areas are urgently required
Subject(s)
Anorexia , Attitude of Health Personnel , Chest Pain , Clinical Competence , Cough , Fever , Health Services Research , Hemoptysis , Practice Patterns, Physicians' , Urban Health Services , Tuberculosis, PulmonaryABSTRACT
The crude aqueous extract of Piper betle leaves (Pb.Cr) was studied for the possible presence of cholinomimetic and calcium channel antagonist constituents. Pb.Cr at doses of 1-10 mg/mL caused a moderate spasmogenic effect in isolated guinea-pig ileum and this activity was concentrated in the aqueous fraction, which was found to be about 5 times more potent. Pretreatment of the tissue with atropine (1 microM) but not hexamethonium (100 microM) completely abolished the contractile effect of the aqueous fraction indicating a cholinergic (muscarinic) mechanism. In isolated rabbit jejunum preparations Pb.Cr did not produce a significant increase in the spontaneous contractions, but instead produced a dose-dependent (0.03-3.0 mg/mL) inhibition of spontaneous activity. Activity-directed fractionation revealed that the spasmolytic action was concentrated in the ethyl acetate fraction. When tested against K(+)-induced contractions, both Pb.Cr and its ethyl acetate fraction (Pb.EtAc) caused a dose-dependent inhibition, suggesting calcium channel blockade (CCB). The potent CCB effect of the crude extract and its ethyl acetate fraction was confirmed when pretreatment of the tissue with Pb.Cr or Pb.EtAc shifted the Ca(++) dose-response curves to the right in a dose-dependent manner. These data indicate that the plant contains cholinomimetic and possible calcium channel antagonist constituents, which are concentrated in the aqueous and ethyl acetate fractions respectively. It is suggested that some of the traditional uses of this plant may be explained on the basis of these activities.
