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Sisinthy Shivaji 《Bioscience reports》1988,8(6):609-618
Proteins present in the seminal plasma of mammals are known to influence functions associated with ejaculated spermatozoa such as motility, capacitation, acrosome reaction and fertilising ability. The proteins isolated and characterised so far influence only one of the above functions of spermatozoa. Seminalplasmin, a protein isolated from the seminal plasma of bull is exceptional in that it influences many of the above spermatozoal functions. It is also a potent antimicrobial protein and capable of lysing microbial and mammalian cells. The physiological function of seminalplasmin as nature's own antifertility agent is discussed. 相似文献
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M S Jawahar S Sivasubramanian V K Vijayan C V Ramakrishnan C N Paramasivan V Selvakumar S Paul S P Tripathy R Prabhakar 《BMJ (Clinical research ed.)》1990,301(6748):359-362
OBJECTIVE--To assess the efficacy of a short course chemotherapy regimen for treating tuberculosis of the lymph nodes in children. DESIGN--Open, collaborative, outpatient clinical trial. SETTING--Outpatient department of the Tuberculosis Research Centre, paediatric surgery departments of the Institute of Child Health and Hospital for Children and the Government Stanley Hospital, Madras, South India. PATIENTS--Children aged 1-12 years with extensive, multiple site, superficial tuberculous lymphadenitis confirmed by biopsy (histopathology or culture). INTERVENTIONS--Patients were treated with a fully supervised intermittent chemotherapy regimen consisting of streptomycin, rifampicin, isoniazid, and pyrazinamide three times a week for two months followed by streptomycin and isoniazid twice a week for four months on an outpatient basis. Surgery was limited to biopsy of nodes for diagnosis and assessment. MAIN OUTCOME MEASURES--Response to chemotherapy was assessed by regression of lymph nodes and healing of sinuses and abscesses during treatment and follow up. Compliance with treatment and frequency of adverse reactions were also estimated. RESULTS--197 Patients were admitted to the study and 168 into the analysis. The regimen was well tolerated and compliance was good with 101 (60%) patients receiving the prescribed chemotherapy within 15 days of the stipulated period of six months. Those whose chemotherapy extended beyond that period received the same total number of doses. Clinical response was favourable in most patients at the end of treatment. Sinuses and abscesses healed rapidly. Residual lymphadenopathy (exceeding 10 mm diameter) was present in 50 (30%) patients at the end of treatment; these nodes were biopsied. Fresh nodes, increase in size of nodes, and sinuses and abscesses occurred both during treatment and follow up. After 36 months of follow up after treatment only 5 (3%) patients required retreatment for tuberculosis. CONCLUSION--Tuberculous lymphadenitis in children can be successfully treated with a short course chemotherapy regimen of six months. 相似文献
5.
Sisinthy Shivaji N. Shyamala Rao L. Saisree Vipula Sheth G. S. N. Reddy Pushpa M. Bhargava 《Journal of biosciences》1988,13(4):409-414
Five cultures isolated from soil samples collected in Schirmacher oasis, Antarctica, have been identified as members of the
familyMicrococcaceae, with 3 belonging to the genusMicrococcus and two toPlanococcus. The 3Micrococcus isolates (37R, 45R and 49R) were red-pigmented and h a d ∼ 75 mol% G + C in their DNA; they were identified asMicrococcus roseus. The twoPlanococcus isolates (30Y and Lz3OR) were yellow and orange in colour, and had 43.5 and 40.9 mol % G + C in their DNA respectively; they
were identified asPlanococcus sp. 相似文献
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Summary Soybean plants were grown in pots with or without vesicular-arbuscular myocorrhizal (VAM) fungi in three soils of low plant-available
P content, different texture and different water-holding capacities. Mineral nutrients, except P, were provided in a complete
nutrient solution. The biomass of non-VAM plants was positively and fungal colonization negatively correlated with increasingly
coarse soil texture. There was no correlation of soil P with host or endophyte growth. Plant growth enhancement was positively
correlated with soil water content at −1.5 MPa. These observations suggest soil water status and the mycorrhizal condition
interact in influencing plant growth. 相似文献
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J Mitra N R Prabhakar J L Overholt N S Cherniack 《Journal of applied physiology》1989,67(5):1814-1819
We studied the central effects of N-methyl-D-aspartate (NMDA) on respiration in 18 artificially ventilated cats anesthetized with alpha-chloralose. Unilateral topical application of NMDA (1 x 10(-8) mol) to the intermediate region of the ventrolateral medulla exaggerates the phrenic response to CO2 at end-tidal PCO2 levels of less than 50.0 Torr. At higher end-tidal PCO2 levels, however, such differences disappear. Unilateral NMDA application increases the activity of the right and left phrenic nerves equally. Furthermore, the magnitude of the phrenic response after unilateral application of NMDA was not different from that after bilateral application. NMDA also had a vasopressor action when applied to the ventrolateral medullary surface. In contrast to respiratory responses, bilateral application of NMDA caused a significant increase in blood pressure compared with unilateral application of NMDA. Application of the NMDA antagonist 2-amino-5-phosphonovaleric acid abolished both the blood pressure and respiratory effects of NMDA. These results suggest that CO2 and NMDA may act on a common respiratory premotoneuron to produce stimulation of breathing. Because blood pressure responses, unlike respiratory responses, were greater after bilateral application than after unilateral application of NMDA, it is suggested that the neural substrates for the two effects of NMDA seem to be different. 相似文献
9.
Changes in the cell surface of vaginal epithelial cells were studied by scanning microscopy and fluorescence spectroscopy. Microvilli which are prominent features of the vaginal epithelial cells in proestrus and diestrus are replaced by sheet-like structures in the estrus phase. Surface morphology of vaginal epithelial cells of estradiol primed rat resembles the vaginal cells from estrus phase rats whereas vaginal cells from control rats resembles the diestrus phase. Measurement of the fluidity of the membranes indicated that the vaginal epithelial cell membrane of estrus rats is more fluid compared to proestrus and diestrus. Similarly, estradiol primed immature rat vaginal epithelial cell membrane was observed to be more fluid than the corresponding control. 相似文献
10.
The psychrotrophic, dimorphic yeast Candida humicola, isolated from Antarctic soil, secretes an acidic protease into the medium. The secretion of this protease by C. humicola was found to be dependent on the composition of the medium. In YPD or yeast nitrogen base medium containing either amino acids or ammonium sulfate as the nitrogen source, the activity of the protease in the medium was low (basal level). However, when yeast nitrogen base medium was depleted of amino acids or ammonium sulfate and supplemented with proteins, the activity of the enzyme increased. The secretion of the enzyme was greater during exponential growth at low temperatures than during growth at higher temperatures. The purified protease had a molecular mass of 36,000 Da and was inhibited by pepstatin, iodoacetamide, and sodium dodecyl sulfate. Despite the prevalent cold temperatures in Antarctica, this extracellular protease of the psychrotrophic yeast C. humicola was active at temperatures ranging from 0 to 45 degrees C, with an optimum activity at 37 degrees C. 相似文献