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排序方式: 共有848条查询结果,搜索用时 23 毫秒
841.
Dr. Dharam V. Ablashi Paul H. Levine Caterina De Vinci James E. Whitman Jr. Giancarlo Pizza Dimitri Viza 《Biotherapy》1996,9(1-3):81-86
Specific Human Herpes virus-6 (HHV-6) transfer factor (TF) preparation, administered to two chronic fatigue syndrome patients,
inhibited the HHV-6 infection. Prior to treatment, both patients exhibited an activated HHV-6 infection. TF treatment significantly
improved the clinical manifestations of CFS in one patient who resumed normal duties within weeks, whereas no clinical improvement
was observed in the second patient. It is concluded that HHV-6 specific TF may be of significant value in controlling HHV-6
infection and related illnesses. 相似文献
842.
A rhesus monkey was inoculated with rhesus cytomegalovirus. A leukocyte-associated herpes virus, unrelated to cytomegalovirus, was later isolated from the same monkey. Four years after the virus inoculation, the monkey developed a disseminated lymphoma. 相似文献
843.
Paola Arena Natalizia Miceli Andreana Marino Federica Davì Emilia Cavò Vivienne Spadaro Francesco Maria Raimondo Francesco Cacciola Roberto Laganà Vinci Luigi Mondello Maria Fernanda Taviano 《化学与生物多样性》2023,20(6):e202300309
This work aimed to investigate Sinapis pubescens subsp. pubescens spontaneously grown in Sicily (Italy) as new potential source of active metabolites; specifically, a comparative study on leaf, flower, and stem hydroalcoholic extracts was performed. Polyphenols were quantitatively determined by spectrophotometric methods and characterized by HPLC-PDA/ESI-MS; a total of 55 polyphenolic compounds were identified, highlighting considerably different qualitative-quantitative profiles. The extracts showed antioxidant activity, evaluated by in vitro assays; particularly, the leaf extract displayed the best radical scavenging activity (DPPH test) and reducing power, while the flower extract showed the greatest chelating activity. The antimicrobial properties of the extracts were investigated against bacteria and yeasts by standard methods; no antimicrobial activity was found against the strains tested. The extracts resulted to be non-toxic after preliminary toxicity evaluation by the Artemia salina lethality bioassay. The aerial parts of S. pubescens subsp. pubescens proved to be valuable sources of antioxidants for pharmaceutical and nutraceutical applications. 相似文献
844.
Sabina Avosani Pietro Franceschi Marco Ciolli Vincenzo Verrastro Valerio Mazzoni 《Journal of Applied Entomology》2021,145(6):518-529
The meadow spittlebug Philaenus spumarius, vector of the bacterium Xylella fastidiosa, relies on vibrational communication to accomplish mating: the female calls to establish a duet with a male. A deeper knowledge of the species’ reproductive biology and behaviour would provide useful information for developing control techniques based on principles of ‘biotremology’, which studies the vibrational behaviour of animals. Playback tests were conducted on single females and male–female pairs of P. spumarius from June to October 2018, and the features of the recorded calling signals were analysed using a wavelet decomposition. Dissections were performed on females to evaluate the relationship between calling activity and ovarioles development. From August onwards, females started to emit calling signals and to develop ovarioles. Female calling activity, duration of their chirps and their responsiveness to mating increased as the season progressed, and they were correlated with ovarioles’ development and presence of mature eggs. Hence, the ovarian maturation represents a key factor in association with the development of the sexual behaviour of P. spumarius females. Conversely, males produced advertisement signals soon after adult eclosion in May, but these signals were not involved in the pair formation process. Mating was achieved only when males produced courtship signals in response to female calling signals and established with them vibrational duets starting from August. Here, we provide new information regarding the P. spumarius’ ethology and hypothesize that potential mating disruption techniques should consider the insect physiology and be applied when both sexes are responsive to mating signals. 相似文献
845.
846.
Filippo Drago Michele Grassi Carmela Valerio Germano Coppi Nunzio Lauria Giulio Cesare Nicotra Rocco Raffaele 《Peptides》1991,12(6):1309-1313
The behavioral activity of the thyrotropin-releasing hormone (TRH) analogue, L-6-ketopiperidine-2-carbonyl-leucyl-L-prolinamide (RGH 2202), has been studied in the rat. The number of errors in a radial maze test was reduced after acute intraperitoneal (IP) injection of RGH 2202 at the dose of 5 or 10 mg/kg. Grooming activity was increased with a lower dose, 1 mg/kg. Hypoxia-induced amnesia, as assessed with active and passive avoidance behavior tests, was reversed in rats treated with 5 or 10 mg/kg of the drug. The loss of learning and memory capacity shown by aged rats in the same behavioral tests was also reduced after injection of RGH 2202. In a test for sexual activity of male rats, the higher dose of the drug induced a facilitation of mounting and ejaculations, while smaller doses were ineffective. The rotorod test revealed a decreased number of falls in animals treated with 5 or 10 mg/kg of RGH 2202. In all behavioral tests, the same doses of natural thyrotropin-releasing hormone (TRH) were less effective, indicating that this analogue may be qualified as a potentially active drug in human pathologies. 相似文献
847.
848.
A M Ferlazzo R Vinci M Panzera A Ferlazzo A Calatroni 《Comparative biochemistry and physiology. B, Comparative biochemistry》1991,100(4):745-751
1. The measured values of acid glycosaminoglycan (GAG) concentration in plasma or in serum show significant differences between trained and untrained horses and among sedentary horses and other animal species (cattle, rabbit, sheep). 2. Diurnal variations in serum GAG levels are reported (cattle), and changes in plasma GAG concentrations after road transport (horses) and in late pregnancy (mares, cows), while sex, age and breed do not affect them. 相似文献