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B S Sandhu

Publications and source records attributed to B S Sandhu.

14 recordsLinked to original sources

Effect of detector collimator and sample thickness on 0.662 MeV multiply Compton-scattered gamma rays.

The simultaneous effect of detector collimator and sample thickness on 0.662 MeV multiply Compton-scattered gamma photons was studied experimentally. An intense collimated beam, obtained from 6-Ci (137)Cs source, is allowed to impinge on cylindrical aluminium samples of varying diameter and the scattered photons are detected by a 51 mm x 51 mm NaI(Tl) scintillation detector placed at 90 degrees to the incident beam. The full energy peak corresponding to singly scattered events is reconstructed analytically. The thickness at which the multiply scattered events saturate is determined for different detector collimators. The parameters like signal-to-noise ratio and multiply scatter fraction (MSF) have also been deduced and support the work carried out by Shengli et al. [2000. EGS4 simulation of Compton scattering for nondestructive testing. KEK proceedings 200-20, Tsukuba, Japan, pp. 216-223] and Barnea et al. [1995. A study of multiple scattering background in Compton scatter imaging. NDT & E International 28, 155-162] based upon Monte Carlo calculations.

Artifacts↗

Beneficial effects of 'lamivudine pulse' therapy in HBeAg-positive patients with normal ALT*.

Currently no therapy is given to patients with chronic hepatitis B virus (HBV) infection who are HBeAg positive with normal alanine aminotransferase (ALT) levels. Steroid priming has been shown to enhance T-helper-1 (Th-1) cell response. Lamivudine may restore immunologic competence against HBV by causing a sudden decline in the level of the virus. We examined the efficacy of lamivudine pulse therapy on the seroconversion from HBeAg to anti-HBe. This was a prospective single-blinded trial including 27 patients with chronic hepatitis B, HBeAg positive with ALT < or =1.5 times upper limit of normal (ULN). Lamivudine was administered initially for 4 weeks, then stopped for 2 weeks and later restarted and continued till 3 months after seroconversion or completion of 2 years of therapy. Twenty-six patients completed the study. Lamivudine withdrawal led to a rise in ALT levels above the ULN in 11 (42.3%) patients at 6 weeks; seven of them (63.6%) lost HBeAg compared with only two of the 15 patients (13.3%), in whom ALT levels did not rise (P = 0.011). As one patient showed a relapse, a total of eight (31%) patients responded to lamivudine pulse therapy over a mean period of 17.3 +/- 4.5 months. Responders had a higher serum albumin (P < 0.05), a lower fibrosis score (P < 0.05), and a relatively high baseline serum ALT levels (P = 0.024) than the nonresponders. YMDD mutations developed in three patients and none responded. No patient developed hepatic decompensation. Hence lamivudine pulse therapy has potential in converting HBeAg-positive, 'not-treat-worthy' (ALT < 1.5 ULN) patients to treat-worthy (ALT > 1.5 ULN) in 42%, with sustained HBeAg and HBV DNA loss in 31% patients. The effects are possibly because of a combination of antiviral and immunomodulating activities of lamivudine.

Adolescent↗

Considerations for esthetic facial surgery in the African-American patient.

Due to the diverse ethnic nature of most communities, the perception of beauty is not homogeneous. Beauty is a perception of good balance, symmetry, harmony, and features that are pleasing to the eye. It is not possible to quantitate beauty. Many attempts have been made to standardize what is and is not beautiful by establishing the ethnic norms. Surgeons commonly attempt to achieve these ideal norms, but they may not necessarily be considered beautiful by the individual patient. Therefore, it is imperative for the surgeon to completely understand the patients' goals for surgery, which may not fit the ideal norms published in studies for that specific ethnic community. It also has become essential for patients to be made aware of the limitations of surgery, especially if their goals are unrealistic, to avert future distress and medicolegal problems. Thus, what is "normal" is not necessarily beautiful, and perhaps it would be better to strive for what is considered beautiful to the individual patient, rather than normal. Within the African-American population, the concept of what is beautiful can be extremely diverse. The number of African Americans who seek cosmetic or esthetic facial surgery is limited. As the number of esthetic procedures performed in the African-American population increases, however, the more educated this population will become regarding these procedures, and the more comfortable the surgeon will become regarding his or her own sense of "African-American beauty" and specific esthetic facial considerations for this population. It should be mentioned that as the number of African-American surgeons increases, their influence within the African-American population regarding the availability of esthetic procedures will also be felt.

Black or African American↗

Haematological and biochemical studies in broiler chicks fed ochratoxin and inoculated with inclusion body hepatitis virus, singly and in concurrence.

Day-old broiler chicks, which had been shown to be negative for maternal antibodies against inclusion body hepatitis (IBH) virus and for viral antigen in cloacal swabs, were divided into four groups of 20 chicks each. One group was fed ochratoxin-A at 0.5 ppm from 3 to 38 days of age, another group was inoculated with 1 ml of IBH virus containing 10(6.5) EID50 per 0.2 ml. A third group was given both ochratoxin-A and infected with IBH virus. The fourth group served as the control. Anaemia was observed in all three treated groups but the changes were more pronounced in the combined group. The biochemical changes also suggested a cumulative damaging effect by ochratoxin-A and IBH virus.

Adenoviridae Infections↗

Giant cavernous hemangiomas of liver mimicking metastasis.

Most hepatic hemangiomas are small and symptomless. These are now being increasingly diagnosed with the greater use of scanning procedures. Hemangiomas can occasionally grow to a large size and become manifest to the patient and the clinician. Giant hemangiomas can produce symptoms including awareness of abdominal mass, pain due to thrombosis, and very rarely, rupture. Though ultrasound is known to be quite suggestive of the diagnosis, large hemangiomas may be mistaken for liver metastases due to their enormous size and variegated picture on the scanning procedure. Dynamic CT scan and at times MRI may be required for confirmation of the diagnosis. Needle biopsy is contraindicated if the diagnosis is suspected.

Adult↗

Pathological studies in broiler chicks fed aflatoxin or ochratoxin and inoculated with inclusion body hepatitis virus singly and in concurrence.

Day-old broiler chicks found negative for maternal antibodies against inclusion body hepatitis (IBH) virus by agar gel precipitation test and viral antigen in cloacal swabs by dot enzyme immunoassay were divided into 6 groups of 20 chicks each. Group A was fed aflatoxin B1 at 1.25 ppm from 3 to 38 days of age; group O was fed ochratoxin A at 0.5 ppm from 3 to 38 days of age; group V was inoculated with 1 ml of IBH virus of titre log10 6.5 EID50 per 0.2 ml. Groups AV and OV were given aflatoxin B1 and ochratoxin A, respectively, and also infected with the virus. Group C served as control. There was mild enlargement and paleness of the liver up to 18 days post inoculation in group V; there were no lesions in group A; and there was gradual enlargement of the kidneys from 10 days post feeding of mycotoxin onwards in group O. In the combined groups AV and OV the gross lesions were slightly more severe. In group V, varying degrees of degenerative histopathological changes, congestion and haemorrhages were seen particularly in the liver, followed by the kidneys, bursa, spleen, myocardium and lungs, along with intranuclear inclusion bodies in the hepatocytes, mostly in the early stages of infection. Similar microscopic changes, but without inclusion bodies, were seen in groups A and O and the changes were pronounced in the later stages. In group O, the kidney lesions were more pronounced than the liver lesions. In the concurrently infected groups, AV and OV, the changes were similar but slightly more marked than in the corresponding individual groups. Inclusion bodies in hepatocytes were more frequent, more prominent and appeared earlier in the concurrent groups.

Adenoviridae Infections↗

Absent and abortive palmar triradii: a review of literature on their association with chromosomal aberrations.

The aetiology of mental retardation is linked with several factors including chromosomal aberrations which in turn are usually accompanied by altered dermatoglyphics. Many other disorders are also associated with chromosomal aberrations. In this paper, chromosomal aberrations producing mental retardation and other conditions, as reported in various published studies, have been reviewed, and the presence and absence of palmar triradii, as possible aids in diagnosing chromosomal anomalies, discussed.

Chromosome Aberrations↗

Sustained release methadone salts and methadone-naloxone mixtures. Part 2: In vitro studies of methadone release.

Various tablet formulations, using two methadone salts namely methadone-alpha-naphthalenesulfonate and methadone-o-benzoylbenzoate and a number of methadone-naloxone combinations were prepared. The quantities of methadone released from these tablets in simulated gastric and intestinal fluids were examined using spectrophoto-metric studies. All formulations followed a typical release pattern, indicating a high degree of consistency of the formulations.

Delayed-Action Preparations↗

Paraganglionoma of extrahepatic biliary tract causing obstructive jaundice.

We report a young woman with paraganglionoma arising from the extrahepatic bile duct presenting with acute obstructive jaundice. The patient underwent excision of the gall bladder and extrahepatic bile duct with the tumor, and Roux-en-Y hepaticojejunostomy. She is asymptomatic 9 months later, with normal biochemical investigations and imaging.

Adult↗

Efficacy of endoscopic wire guided biliary brushing in the evaluation of biliary strictures.

Endoscopic brush cytology is a valuable technique for the evaluation of biliary strictures. The sensitivity of this technique varies from 30% to 83%, however, it can have specificity of 100%. We retrospectively evaluated the usefulness of wire-guided biliary brush cytology in biliary strictures in our hospital over a 3 years period from 1997 to 2000. Brushings from 58 biliary strictures were obtained during endoscopic retrograde cholangiography. They were compared with histological proof obtained by surgical biopsy or percutaneous fine-needle aspiration cytology and/or clinical findings. These were reported as benign or malignant. Eleven patients were excluded due to incomplete data. Eighteen patients had benign brushings. Fourteen of the 29 patients in whom histological confirmation of malignancy brushings was obtained were also reported as malignant. The sensitivity of endoscopic brushings was 48.2%, specificity 100% and diagnostic accuracy 55.2%. No major complications were seen in our study group.

Bile Duct Neoplasms↗