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1.
Zero-order release of oxprenolol hydrochloride was obtained by controlling the swelling and erosion of the matrix. This formulation involves only mixing of drug, hydroxypropylmethylcellulose (HPMC), and sodium carboxymethylcellulose (Na CMC) at the ratio of 1:0.4:1.6, respectively, and compressing the mixture directly into tablets. The in vitro release pattern from this optimized matrix tablet was reproducible. Accelerated stability studies revealed that the optimized formulation remains stable for an approximately 2-year shelf life. This sustained-release (SR) tablet was evaluated in dogs, and for comparison a conventional (CV) formulation was also given at the same dose level. Plasma oxprenolol levels were monitored by a sensitive and specific high-performance liquid chromatographic (HPLC) method. Significant differences in the pharmacokinetic parameters, i.e., lower C max, higher values of t max, MRT, AUC, and plasma concentration at 24 hr, and nearly constant plasma levels over 12 hr, indicated that the SR matrix tablet is superior to the CV rapid-releasing formulation. The in vitro release parameters and in vivo pharmacokinetics correlated well.  相似文献   
2.
Intravascular papillary endothelial hyperplasia (IPEH) is an unusual vascular lesion of proliferating endothelial cells. It is more frequently seen in the extremities, particularly in the fingers. Oral IPEH has been reported with the common sites being lip, tongue, and buccal mucosa. In this article, we present a case of oral IPEH of the floor of the mouth, an unusual location, presenting in a 9-month-old male. The histogenesis, histologic features, and ultrastructural features are also reviewed. A misdiagnosis of angiosarcoma can be made in a case of IPEH due to similar histopathologic features. It is imperative to rule out this error by an elaborate histopathologic evaluation ofthese lesions.  相似文献   
3.
The alterations in the oesophageal epithelium were studied in mice after a single whole-body exposure to 7.5 Gy of Co-60 gamma rays in presence or absence of 2-mercaptopropionyl glycine. The epithelium showed an increase in the thickness which reached a maximum on the third day and then decreased gradually up to seventh day after irradiation in the non-drug treated group. In the 2-mercaptopropionyl glycine treated animals the epithelial thickness remained in the normal range except on the day 7 when it was significantly lower than normal. The total cell population registered a steady decline from one to seven days post-irradiation in both groups, but the number of cells was more in the 2-mercaptopropionyl glycine treated group. The number of pycnotic nuclei showed an inverse relationship to the total cell population, it increased continuously up to seven days in both the protected and non-protected groups. However, pycnotic nuclei were significantly lower in the protected group on days 3, 5 and 7 in non-protected group.  相似文献   
4.
Two children out of three siblings of a family presented with tiredness, fatigue, and breathlessness for more than 6 months. Examination of peripheral blood smear, bone marrow aspirate, and a positive acidified serum test (HEMPAS) revealed these children to be a case of congenital dyserythropoietic anemia type II. This case is reported because of its rarity.  相似文献   
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The allele-specific PCR approach has been modified by introducing a second mismatch at the 3'-penultimate link of the primer and used to identify the sickle cell anemia mutation (A-->T transversion in the sixth codon of the human beta-globin gene causing Glu-->Val substitution in the protein), thus obviating the problem of an interpretationally ambiguous 3'-terminal mismatch including T residue.  相似文献   
7.
Consanguineous marriages are strongly favoured among the populations of South India. In a study conducted on 407 infants and children, a total of 35 genetic diseases was diagnosed in 63 persons: 44 with single gene defects, 12 with polygenic disorders, and seven with Down's syndrome. The coefficient of inbreeding of the total study group, F = 0.0414, was significantly higher than that previously calculated for the general population, F = 0.0271, and autosomal recessive disorders formed the largest single disease category diagnosed. The results suggest that long term inbreeding may not have resulted in appreciable elimination of recessive lethals and sub-lethals from the gene pool.  相似文献   
8.
A study of 190 children of chronic cervical lymphadenitis showed tuberculous etiology on histopathological examination in 92 (48.4%) and bacteriological evidence of mycobacterial infection (smear and/or culture) in 42 (22.1%). Of these 42, twelve (28.6%) showed histopathological diagnosis of non-specific lymphadenitis. Positive culture for mycobacteria was obtained in 40, of which 30 (75%) were typical M. tuberculosis and 10 (25%) were atypical mycobacteria. The most predominant species of typical mycobacteria was M. scrofulaceum (60%) followed by M. avium intracellulare (40%). There was no remarkable difference in the histopathological pattern of those in which M. tuberculosis was grown and those in which bacterial growth was that of atypical mycobacteria. The diagnosis of chronic cervical lymphadenitis should therefore be taken a step beyond histopathology, up to complete bacteriological examination, especially to confirm the cases of mycobacterial lymphadenitis caused by atypical mycobacteria.  相似文献   
9.
The 16-kDa cytosolic antigen of M. tuberculosis was purified to homogeneity by molecular sieving chromatography, and the diagnostic potential of the antigen was evaluated in various categories of patients by enzyme-linked immunosorbent assay (ELISA). The immunoglobulin G (IgG), IgA, and IgM antibody levels to 16-kDa antigen were estimated in the two polar groups, namely, smear- and culture-positive pulmonary tuberculosis (S+C+) patients and healthy subjects (HS). Sensitivities of 62, 52 and 11% with specificities of 100, 97, and 95% were obtained for the three isotypes, respectively. The total number of positives by a combination of the three isotypes was analyzed in the polar groups, and the sensitivity improved to 83% with a specificity of 93%. Even when a combination of IgG and IgA alone was considered, the sensitivity was 82% with a specificity of 97%. Polyethylene glycol precipitation of the circulating immune complex (CIC) in sera was carried out. The CIC-bound antibodies to 16-kDa antigen were assessed by ELISA in the S+C+, SC+, and SC categories of patients. Measuring the IgG-IgA-IgM combination positivities of the CIC-bound antibodies gave sensitivities of 97.5, 100, and 45.3%, respectively. The specificity of the assay with these combinations was maintained at 95.4%.  相似文献   
10.
Banna virus (BAV, genus Seadornavirus, family Reoviridae) is an arbovirus suspected to be responsible for encephalitis in humans. Two genotypes of this virus are distinguishable: A (Chinese isolate, BAV-Ch) and B (Indonesian isolate, BAV-In6969) which exhibit only 41% amino-acid identity in the sequence of their VP9.The VP7 to VP12 of BAV-Ch and VP9 of BAV-In6969 were expressed in bacteria using pGEX-4T-2 vector. VP9 was chosen to establish an ELISA for BAV, based mainly on two observations: (i). VP9 is a major protein in virus-infected cells and is a capsid protein (ii). among all the proteins expressed, VP9 was obtained in high amount and showed the highest immuno-reactivity to anti-BAV ascitic fluid.The VP9s ELISA was evaluated in three populations: French blood donors and two populations (blood donors and patients with a neurological syndrome) from Malaysia, representing the region where the virus was isolated in the past.The specificity of this ELISA was >98%. In mice injected with live BAV, the assay detected IgG-antibody to BAV infection 21 days post-injection, which was confirmed by Western blot using BAV-infected cells.The VP9 ELISA permits to determine the sero-status of a population without special safety precautions and without any requirements to propagate the BAV. This test should be a useful tool for epidemiological survey of BAV.  相似文献   
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