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41.
Fine needle aspiration of focal liver lesions 总被引:1,自引:0,他引:1
Fourteen percutaneous fine needle aspirates (FNAs) of focal liver lesions performed under ultrasound guidance at the Sultan Qaboos University Hospital (SQUH), Oman, between January 1991 and October 1992, are presented. Ten of these were cytologically diagnosed as hepatocellular carcinomas (HCC). the patients' ages ranged from 50 to 70 years and eight of these were males. the important diagnostic cytological criteria of HCC were found to be increased nucleocytoplasmic (N/C) ratio, trabecular pattern, atypical naked nuclei, bile production by malignant hepatocytes and absence of bile duct epithelium. Carcinoembryonic antigen (CEA) positivity of bile canaliculi by cross-reaction with biliary glycoprotein I (BGP I) made possible the differentiation of HCC from metastases. We stress the importance of cell blocks as these often constitute microbiopsies. Ultrasound-guided FNA of focal liver lesions is recommended as a simple, easy and quick procedure. 相似文献
42.
Kumar S Sharma V Chaudhary S Tyagi A Mishra P Priyadarshini A Singh A 《Journal of genetics》2012,91(1):33-47
Time to flowering in the winter growth habit bread wheat is dependent on vernalization (exposure to cold conditions) and exposure to long days (photoperiod). Dominant Vrn-1 (Vrn-A1, Vrn-B1 and Vrn-D1) alleles are associated with vernalization independent spring growth habit. The semidominant Ppd-D1a mutation confers photoperiod-insensitivity or rapid flowering in wheat under short day and long day conditions. The objective of this study was to reveal the nature of interaction between Vrn-1 and Ppd-D1a mutations (active alleles of the respective genes vrn-1 and Ppd-D1b). Twelve Indian spring wheat cultivars and the spring wheat landrace Chinese Spring were characterized for their flowering times by seeding them every month for five years under natural field conditions in New Delhi. Near isogenic Vrn-1 Ppd-D1 and Vrn-1 Ppd-D1a lines constructed in two genetic backgrounds were also phenotyped for flowering time by seeding in two different seasons. The wheat lines of Vrn-A1a Vrn-B1 Vrn-D1 Ppd-D1a, Vrn-A1a Vrn-B1 Ppd-D1a and Vrn-A1a Vrn-D1 Ppd-D1a (or Vrn-1 Ppd-D1a) genotypes flowered several weeks earlier than that of Vrn-A1a Vrn-B1 Vrn-D1 Ppd-D1b, Vrn-A1b Ppd-D1b and Vrn-D1 Ppd-D1b (or Vrn-1 Ppd-D1b) genotypes. The flowering time phenotypes of the isogenic vernalization-insensitive lines confirmed that Ppd-D1a hastened flowering by several weeks. It was concluded that complementary interaction between Vrn-1 and Ppd-D1a active alleles imparted super/very-early flowering habit to spring wheats. The early and late flowering wheat varieties showed differences in flowering time between short day and long day conditions. The flowering time in Vrn-1 Ppd-D1a genotypes was hastened by higher temperatures under long day conditions. The ambient air temperature and photoperiod parameters for flowering in spring wheat were estimated at 25°C and 12 h, respectively. 相似文献
43.
R. KUMAR 《Zoological Journal of the Linnean Society》1975,57(2):179-184
A new genus Princisaria belonging to family Blaberidae is described from Africa. A key to the African genera of the subfamily Laxatinae is given. Three new species, P. carvalhoi, P. ugandana and P. curta are described. 相似文献
44.
S. FIREMPONG R. KUMAR 《Biological journal of the Linnean Society. Linnean Society of London》1975,7(4):261-292
Natural enemies of the black citrus aphid, Toxoptera aurantii (Boy.), on cocoa in Ghana are identified. Biology of some of the natural enemies is followed. Behaviour of the coccinellid and syrphid predators is studied in detail. Effectiveness of the predators in reducing the aphid populations is discussed. 相似文献
45.
JEFFREY G. SNODGRASS MICHAEL G. LACY SATISH KUMAR SHARMA YUVRAJ SINGH JHALA MOHAN ADVANI N. K. BHARGAVA CHAKRAPANI UPADHYAY 《American anthropologist》2008,110(3):299-312
ABSTRACT In this article, we examine the environmental thought and practice of indigenous peoples living in and around a wildlife sanctuary in North India. Analysis reveals that those religious specialists (such as shamans) who possess knowledge of herbal healing are more committed than other villagers to preventing or mitigating the overharvesting of natural resources. To explain these results, reference is made to a specific juncture of native traditions and modern conditions and in particular to an intersection of local economies with global discourses of "ecodevelopment." Drawing on theories and methods from political ecology and cultural psychology, we present a framework for testing the extent that local actors—in this case, shamanic and herbalist healers—are differently positioned to resist or accommodate state and parastate structures of "environmentality" than are other villagers. 相似文献
46.
GA3 as well as SA (salicylic acid) and β-N (β-naphthol) induce floral buds in Impatiens balsamina under strictly non-inductive photoperiods. The floral bud initiation is accelerated when 1 mg/1 SA is used in combination with 100 mg/1 GA3. 100 mg/1 GA3+ 1 mg/1 SA and 100 mg/1 GA3+ 100 mg/1 β-N increase the number of floral buds as compared with 100 mg/1 GA3 alone. 相似文献
47.
B. A. FUSEINI R. KUMAR 《Biological journal of the Linnean Society. Linnean Society of London》1975,7(2):113-146
An account is given of the ecology of four species of Dysdercus in southern Ghana. Succession of host plants, host preference and migration is studied. Colony structure is examined. Natural enemies are investigated. Mimetic resemblance of the resident predator to a particular species of host Dysdercus is studied. Experiments on the palatibility of Dysdercus species to mammalian predators are discussed. 相似文献
48.
49.
Relatively low concentrations of streptomycin inhibited thegrowth of Anacystis nidulans and Anabaena variabilis. The productionof chlorophyll, carotenoid, and phycocyanin pigments in thesealgae was significantly but reversibly inhibited by streptomycin.Strains of Anacystis nidulans that are resistant to streptomycinand penicillin were produced by serially subculturing the algain gradually increasing concentrations of the respective antibiotic.These strains seem stable. Evidence which suggests that theresistant strains originate primarily by mutation is presented. 相似文献
50.