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1.
The protein and gene sequences of the cowpea Bowman-Birk type trypsin inhibitor which confers enhanced insect resistance to transgenic tobacco plants, and of cowpea trypsin/chymotrypsin inhibitors are presented. There are regions of high conservation and high divergence within the 5 leader, mature protein and 3 non-coding regions of the Bowman-Birk inhibitors and in the genes which encode them in different members of this family within the Leguminosae. The practical implications of this finding for studies on the evolution of plants and the utilization of these genes for enhancing insect resistance is discussed.  相似文献   
2.
R Rone  I Ramzy  D Duncan 《Acta cytologica》1986,30(2):183-188
A case of sacrococcygeal chordoma with anaplastic features is presented. The diagnosis of the anaplastic component was first established by fine needle aspiration (FNA) biopsy, which demonstrated the sarcomatous elements as well as the physaliferous cells characteristic of chordoma. Subsequent histologic examination confirmed these findings. While the FNA cytologic findings of chordoma have been previously reported, this is the first case of an anaplastic chordoma diagnosed by FNA biopsy. The embryologic origin of this unusual tumor and its differential diagnosis are discussed.  相似文献   
3.
A 61-year-old male native of Mexico presented with generalized enlargement of lymph nodes. Fine needle aspiration (FNA) biopsy established lepromatous leprosy as the cause of the lymphadenopathy. The cytologic findings included abundant, frequently multinucleated histiocytes (globus cells), the cytoplasm of which showed multiple vacuoles; cytoplasmic membrane-bound vacuoles were seen free in the background. The vacuoles contained large numbers of acid-fast bacilli. Globus cells, while characteristic, are not specific for Mycobacterium leprae infection and are seen in certain atypical mycobacterioses in immunodeficient patients. This appears to be the first report of lymphadenopathy due to lepromatous leprosy in which the diagnosis was made by FNA biopsy. The immunologic spectrum of leprosy is correlated with clinical and pathologic findings, and the need to remember infectious processes in evaluating lymphadenopathy and the value of reserving air-dried and alcohol-fixed smears for special stains are emphasized.  相似文献   
4.
Fine needle aspiration biopsies of tumors can yield a variety of spindle cells derived from several types of neoplasms. Among these is a rare lesion known as a "spindle-cell carcinoma" or "pseudosarcoma," which may represent a transformation of a preexisting squamous-cell carcinoma that has been subjected to radiotherapy or solar damage. The cytologic, histologic and ultrastructural features of a case of metastatic spindle-cell carcinoma of the rib subjected to fine needle aspiration are presented, and other spindle-cell tumors that should be considered in the differential diagnosis are discussed.  相似文献   
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Summary An efficient, aseptic method of obtaining whole broth fermentation samples was developed based on a piston-valve, a local sample loop, and an ability to drive the entire sample volume with sterile air through a sample line and into a remote tube. The configuration delivers 10-ml samples 10 m away with about 4 ml of broth wasted in the sampling process. An autosampler was enhanced and programmed to control acquisition into chilled tubes. The autosampler-based system represents a convenient way to provide frequent samples to profile intracellular and extracellular components for yeast and bacterial fermentations. A configuration to provide sampling from six fermentors with a multi-rack autosampler will be presented.  相似文献   
7.
Fatma Reda 《Planta》1976,130(3):265-268
Summary The soybean callus assay was used to study the effect of vernalization on the endogenous cytokinin levels of the grains of winter wheat (Triticum vulgare L.), cv. Ferto and Fema. Vernalization of the grains was carried out at 3° C in the dark for 0, 9, 18, 27, 36 and 45 days. Cytokinin activities could be detected in both the aqueous and butanol extracts of vernalized grains of both cultivars. It is suggested that flowering of winter wheat may involve changes in the levels of endogenous cytokinins during vernalization.  相似文献   
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The genus Lavandula is known for its different uses in traditional medicine. This study is interested in the chemical composition of Lavandulapedunculata subsp.atlantica (Braun‐Blanq. ) Romo as well as evaluating its antibacterial potential against multi‐resistant strains. The analysis of Lavandulaatlantica essential oil (LAEO) allows the identification of 47 components representing 93.6 % of all identified. The main constituent of LAEO was camphor (50.4 %), followed by fenchone (14.1 %) and camphene (5.6 %). The antibacterial assays revealed that LAEO was active against all the studied bacteria. A preliminary study of the relationship between certain terpenoids and antibacterial activity was also carried out in order to note the compound(s) that are responsible for LAEO's antibacterial activity. This study showed that the activity of the essential oil may be due to the presence of certain minor compounds such as carvone, considering the presence of the synergistic effect between the essential oil.  相似文献   
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