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11.
L-Triiodothyronine (T3) binding to hepatic nuclei from (ob/ob) mice at different ages was examined and compared with that of lean controls. Results showed a significant reduction in T3 binding in liver nuclei of obese mice at all ages studied. The preobese mice at 2 weeks of age had 27.9% fewer receptor sites/mg DNA compared to lean controls, receptor concentration further decreased to 67.7% at 18 weeks of age. Data presented here demonstrates that the impaired triiodothyronine (T3) binding to hepatic nuclei present in older (ob/ob) obese mice is an antecedent to the obesity. This report also helps to explain the poor thermoregulation and low oxygen consumption present during the preobese phase of the postnatal development of these animals.  相似文献   
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Influence of Lernaeocera branchialis, a hematophagous copepod, on the growth rate of Atlantic cod, Gadus morhua, was investigated in fish of various sizes. Initially, it appeared that growth, over a 16-mo period, was reduced when single or multiple infections were present. We then examined growth rate by comparing food consumption, weight gain, food conversion efficiency, and condition (k) factor over a 2-mo period and subsequently over a 4 wk in control and experimentally infected fish. Total body weight and length of each fish, controls and infected were determined before and after feeding known weights of food. Adults infected with young parasites consumed more food and gained more weight than controls, especially in the first month, but food conversion efficiency and k-factor were greater than those of controls after 2 mo, but food efficiency was still lower than in controls. In 2 groups of young infected fish, all values were consistently lower than those of uninfected fish of comparable size during the 2-mo period. Three additional trials on immature cod confirmed that infected fish consumed less food and exhibited less growth than infected controls. Our results suggest that only adult cod infected with immature parasites compensate for the infections by increasing food consumption, thus resulting in a transitory weight gain. Additionally, parasites that have completed their reproductive activities still produce subtle effects in the form of low food conversion efficiency in their hosts.  相似文献   
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A 30-year-old woman presented with a lump in the left breast and left axillary lymphadenopathy that, on fine needle aspiration cytology (FNAC), proved to be duct cell carcinoma with metastasis. Histology of the radical mastectomy specimen showed a mixed colloid carcinoma. Axillary lymph nodes revealed a variety of pathologic changes consisting of reactive hyperplasia, tuberculosis and metastasis. A combination of a tuberculous lesion and metastasis in the same lymph nodes was also found. During follow-up, after radiotherapy, the patient developed left supraclavicular and right cervical lymphadenopathy that, on FNAC, revealed a tuberculous lesion and metastasis, respectively. The rarity of this condition with double pathology is highlighted, and the reason behind the limitations of FNA in subtyping the primary malignancy and its failure to detect the tuberculous lesion in the axillary lymph node are discussed.  相似文献   
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Commercially-available phenol red indicator, purified by adsorption chromatography was incorporated into lauryl sulphate broth (LSB) used in the membrane filtration method for the detection of Escherichia coli and other coliform bacteria. Relative to LSB containing the impure dye or its major contaminant, the purified phenol red provided clear visualization of discrete yellow colonies observed against a white background. The colonies remained stable for at least 24 h at 25°C under standard laboratory lighting conditions. This simple procedure will enhance the detection of coliforms in samples.  相似文献   
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Khan  M. A.  Kamuru  F. 《Hydrobiologia》1997,354(1-3):151-156
Seasonal studies were undertaken (August 1983–July 1984) toevaluate the algal distribution and ecology of the RiverDelimi, Jos Plateau, Nigeria at three stations: upstream, withlittle allochthonous input; midstream, receiving heavy domesticaffluents; downstream. A wide amplitude of variability wasdiscernible in physicochemical factors, and photosyntheticactivity and abundance of suspended algae in relation to thedegree of pollution along the first 7-km stretch of the river.Conductivity (µS cm-1) showed a 9-fold increase fromupstream (x = 35) to downstream. The standing crop(Chl a) fluctuated markedly, with 6-times higher valuesfor a polluted midstream site (x = 18.2 mg m-3). Production rate measurements (mg C m-3 d-1) showed significant variability with relatively lowvalues (x = 610) recorded for the upstream andhighest (x = 1050) at the midstream site. Apositive correlation was obtained between production rates andChl a for the polluted midstream zone.  相似文献   
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Sandhu  R. S.  Bardana  E. J.  Khan  Z. U.  Dordevich  D. M. 《Mycopathologia》1978,63(1):21-27
Serum specimens from 138 patients suffering from chronic respiratory disorders including 63 with allergic bronchopulmonary aspergillosis (ABPA), 20 with suspected ABPA, 25 with pulmonary tuberculosis, 14 with bronchial asthma, 10 with chronic bronchitis and 6 with miscellaneous pulmonary conditions were studied for circulating antibodies to Aspergillus. The ammonium sulfate test was employed with an iodine-125 labeled mycelial component derived from Aspergillus fumigatus. When compared to normal controls from the same area, this test indicated that sera from 82 per cent of patients with ABPA had elevated binding titers to the radiolabeled antigenic component. Immunodiffusion using a culture filtrate antigen from A. fumigatus, revealed precipitating antibody to this fungus in 89 per cent of sera from ABPA patients. The majority of patients with ABPA demonstrated marked elevations of total serum IgE, moderate elevations of serum IgA and IgD and slightly increased levels of IgG and IgM.This study was supported in part by Research Grant AI 10940 from the National Institutes of Health and by NHLI Contract N01-HL-3-2942(B), and forms a part of the Ph.D. thesis submitted by Z.U.K. to the University of Delhi.  相似文献   
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Tests were made to determine the effects of inorganic and organic sulfur sources on the degradation of cellulose to methane in a chemically defined medium with sulfur-poor inoculum prepared from sewage sludge. The results show that a sulfur source of about a 0.85 mM concentration is essential for the degradation of cellulose to CH4. However, the production of CH4 from CO2 and H2 provided in the headspace occurred with 0.1 mM sulfate or sulfide. At a 9 mM concentration, all inorganic sulfur compounds other than sulfate inhibited both cellulose degradation and methane formation, and this inhibition increased in the order thiosulfate less than sulfite less than sulfide less than H2S. It appears that the degradation of cellulose to CH4 in a sulfate-free medium by inoculum maintained in a low-sulfur medium is inhibited because of the lack of availability of sulfur for growth of bacteria and synthesis of cell materials and sulfur-containing cofactors involved in cellulose degradation and methanogenesis. The reduction of methanogenesis by higher levels of sulfate probably occurs as a result of stimulation of reactions converting acetate and H2 to end products other than CH4.  相似文献   
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