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A K Singal

Publications and source records attributed to A K Singal.

10 recordsLinked to original sources
PubMed1995

Difficulties with unification.

The difficulties perceived in the orientation-based unified scheme models, when confronted with the observational data, are pointed out. It is shown that in meter-wavelength selected samples, which presumably are largely free of an orientation bias, the observed numbers of quasars versus radio galaxies are not in accordance with the expectations of the unified scheme models. The observed number ratios seem to depend heavily on the redshift, fluxdensity, or radio luminosity levels of the selected sample. This cannot be explained within the simple orientation-based unified scheme with a fixed average value of the half-opening angle (c approximately 45 degrees ) for the obscuring torus that supposedly surrounds the nuclear optical continuum and the broad-line regions. Further, the large differences seen between radio galaxies and quasars in their size distributions in the luminosity-redshift plane could not be accommodated even if I were to postulate some suitable cosmological evolution of the opening angle of the torus. Some further implications of these observational results for the recently proposed modified versions of the unified scheme model are pointed out.

Journal Article↗
PubMed1994

Use of micro samples of finger prick blood dried on filter paper for a quick and simple dipstick dot-EIA for diagnosis of amebic liver abscess (ALA).

Filter paper was used as a support to absorb micro samples of finger prick blood for detection of antibodies to Entamoeba histolytica (causative organism of amebiasis) by a rapid dipstick dot-EIA technique; 8 microliters of blood was sufficient to saturate discs (diameter 6 mm) of Whatman paper No. 3. Conditions of elution of blood from the discs were optimized and the best results were obtained when 0.4 ml of buffer was used for elution for 30 minutes at room temperature. The filter paper technique is extremely useful for field use and for diagnosis of amebic liver abscess on a large scale since it does not involve centrifugation of blood and use of sterile vials because blood dried on paper can be stored in polythene bags at room temperature for up to 3 months and for a week at 42 degrees C without significant loss of antibody activity, thereby eliminating the need of refrigeration of samples for storage or transportation to a reference laboratory. Elution of blood from different discs of the same patient was found to be highly reproducible without appreciable loss of sensitivity or specificity. Twenty-four confirmed ALA, 29 non-ALA, and 25 apparently normal healthy controls, with no previous history of amebiasis, were tested. Sensitivity and specificity of the test was found to be 96% and 92%, respectively.

Animals↗
PubMed1991

Splenoportovenography: safety, success rate and hemodynamic changes, and incidence and natural history of splenic hematoma.

Forty-five non-cirrhotic patients undergoing splenoportovenography (SPV) were studied. SPV was performed successfully in 43 (95.5%) patients. Local pain was encountered in 12 (26.6%) and lasted for a mean (+/- SD) of 7 +/- 3.8 hours. Local tenderness was noted in 17 (37.7%) and lasted for 6.8 +/- 3.7 hours. The mean rise in the pulse rate after the procedure was 6.5 +/- 4.7 beats per minute and the fall in the systolic and diastolic blood pressures was 3.4 +/- 2.5 and 0.8 +/- 1.7 mmHg respectively. Post-SPV splenic hematoma was noted in 3 (6.6%) patients. All were subcapsular, at the site of puncture, and disappeared by the seventh day. There was no difference in the age, change in the pulse rate, and fall in systolic or diastolic blood pressures between those who developed and those who did not develop hematoma. One patient required one unit of blood transfusion. There were no deaths. SPV was noted to be a simple and safe procedure with a high success rate with minimal morbidity and no mortality.

Adolescent↗
PubMed1989

Cimetidine in the treatment of non-ulcer dyspepsia: results of a randomized double-blind, placebo-controlled study.

A randomized double-blind, placebo-controlled study was carried out in 56 patients with essential dyspepsia to investigate the therapeutic efficacy of cimetidine in providing symptomatic relief. Patients received either 1 tablet of cimetidine (400 mg) or identical looking placebo twice daily for a period of 4 weeks. A detailed symptomatic assessment was made at weekly intervals. Abdominal pain, the primary symptom, was relieved in a higher proportion of cimetidine-treated patients compared to placebo group (67% versus 40%, p less than 0.05). Most of the secondary gastro-intestinal symptoms also improved in a higher proportion of patients in the cimetidine group although the difference was statistically not significant. The outcome of treatment was not influenced by factors such as duration of disease, initial severity of pain and smoking habits of the patient.

Adolescent↗
PubMed1988

Ulceration after esophageal and gastric variceal sclerotherapy--influence of sucralfate and other factors on healing.

Forty-five consecutive patients underwent sclerotherapy with absolute alcohol. Post-sclerotherapy ulcers were detected in all of them (100%) on the following day. In order to evaluate its influence on ulcer healing, 20 patients were given sucralfate (1 g QID before meals), while 25 patients received identical-looking placebo, in a double-blind randomised manner. Endoscopy done at weekly intervals revealed healing of ulcers in 25%, 55%, 95% and 100% in the sucralfate, and 24%, 40%, 72% and 84% in the placebo group at 1, 2, 3, and 4 weeks, respectively. Differences between the two groups were not significant. Gastric variceal ulcers healed better with sucralfate (7 out of 7) than placebo (0 out of 2). Healing was influenced by the size of the ulcer. At two weeks, 63% of ulcers less than 1 cm, 43% of ulcers 1-2 cm, and only 16.6% of ulcers greater than 2 cm had healed. The size of the ulcer also correlated with the amount of the sclerosant injected. Our results show that (a) mucosal ulcers universally develop after adequate sclerotherapy, (b) most ulcers heal spontaneously, (c) sucralfate does not hasten ulcer healing, with the exception of gastric variceal ulcers, (d) a larger amount of sclerosant produces larger ulcers that take longer to heal.

Adult↗
PubMedDate not supplied

Endoscopic sclerotherapy for varices in children.

Thirty-one children with variceal bleeding due to portal hypertension (extrahepatic obstruction 19, non-cirrhotic portal fibrosis five, and cirrhosis of liver seven patients) were treated with endoscopic sclerotherapy with absolute alcohol. Acute variceal bleeding was successfully controlled in 10 patients by emergency sclerotherapy. A 3 weekly schedule of sclerotherapy could achieve obliteration of varices in all the patients. The mean (+/- SD) number of sclerotherapy courses and the time required for variceal eradication was 4.5 +/- 1.7 and 14.4 +/- 3.9 weeks, respectively. During a mean follow-up of 23.3 +/- 11.4 months, variceal recurrence was seen in three (9.7%) patients, two with cirrhosis and one with noncirrhotic portal fibrosis. Recurrence was not seen in any patient with extrahepatic obstruction. Five (16.1%) patients had a rebleed that could be controlled with emergency sclerotherapy. Esophageal stricture developed in four (12.9%) patients and could be dilated easily in all of them. The other complications of sclerotherapy included retrosternal pain, dysphagia, and fever; these were mild and short lasting. Survival in patients with extrahepatic obstruction and noncirrhotic portal fibrosis was 100%. The only death was in a cirrhotic, who died due to terminal hepatic failure. In conclusion, endoscopic sclerotherapy can be recommended as a safe and effective treatment in children for the control of acute variceal bleeding and for variceal obliteration.

Adolescent↗
PubMedDate not supplied

Traveler's diarrhea-I. Definition, etiology and epidemiology.

With the development of rapid and convenient means of transportation, several million persons travel from industrialized countries to developing countries every year. From USA alone, approximately 4 million persons visit Mexico annually. These travelers are at risk to develop several infections during their stay abroad, but the most commonly experienced illness is diarrhea. The attack rate of diarrhea in travelers may be as high as 25 to 50 percent; 30 percent of those who get diarrhea are ill enough to be confined to bed and another 40% have to change their scheduled travel plans. The disease affects all ranks and it has achieved worldwide fame by its several euphemisms. Various epithets used to describe this illness include GI trots, Aden gut, Barsa belly, Turkey trot, Delhi belly, Hongkong dog, Montezuma's revenge, gyppsy tummy and turista. There have been considerable advances in our understanding about the etiology and epidemiology of this disease in the last two decades and the purpose of this review is to highlight some of this new information.

Diarrhea↗