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201.
M. Correale I. Abbate A. Paradiso F. Schittulli C. D. Dragone T. Tedone G. Gargano A. M. Catino M. D. Musci M. De Lena 《Cell biochemistry and biophysics》1993,22(1-3):101-110
Using a new immunoradiometric assay (ELSA pS2 Cis-France), a total of 200 cytosols obtained from primary breast tumors were examined for pS2 content, which is an estrogen-regulated protein actually studied as a marker of hormone sensitivity and favorable prognostic factor in breast cancer. In our patient group, the median pS2 value corresponding to 5.3 ng/mg of cytosolic proteins was used as cutoff. pS2 content was not related to menopause status, tumor size, or nodal involvement, whereas a positive correlation was found between pS2 and ER/PgR status. Moreover, the association of pS2 with steroid receptors seems to identify subgroups of patients better than ER/PgR alone. 相似文献
202.
Jirillo E Altamura M Marcuccio C Tortorella C De Simone C Antonaci S 《Mediators of inflammation》1993,2(7):S17-S20
Tuberculosis (TBC) is characterized by a complex immune response which parallels the clinical course of the disease. In this respect, acquired resistance, delayed hypersensitivity reaction and anergy are the main types of immune reactivity to mycobacterial antigens. In view of the presence of nonspecific and specific immune deficits in TBC patients, a clinical trial was carried out in a group of 20 individuals with active pulmonary TBC by oral administration of acetyl-L-carnitine (ALC). This drug, which has been shown to possess immunomodulating activities, was able to upregulate the T-dependent antibacterial activity in TBC patients after 30 days' treatment, while the same activity decreased in patients receiving placebo only. On the other hand, ALC did not modify serum levels of tumour necrosis factor-alpha, in the same individuals. This cytokine plays a detrimental rather than beneficial role in TBC pathogenesis. In the light of these data, ALC seems to be a powerful immunomodulator in the course of Mycobacterium tuberculosis infection and other mycobacteriosis. 相似文献
203.
Abstract. Different sets of cell kinetic data obtained over many years from hairless mouse epidermis have been simulated by a mathematical model including circadian variations. Simulating several independent sets of data with the same mathematical model strengthens the validity of the results obtained. The data simulated in this investigation were all obtained with the experimental system in a state of natural synchrony. The data include cell cycle phase distributions measured by DNA flow cytometry of isolated epidermal basal cells, fractions of tritiated thymidine ([3 H]TdR) labelled cells within the cell cycle phases measured by cell sorting at intervals after [3 H]TdR pulse labelling, bivariate bromodeoxyuridine (BrdUrd)/DNA data from epidermal basal cells isolated at intervals after pulse labelling with BrdUrd, mitotic rate and per cent labelled mitosis (PLM) data from histologic sections. The following main new findings were made from the simulations: the second PLM peak observed at about 35 h after pulse labelling is hardly influenced by circadian variations; the peak is mainly determined by persisting synchrony of a rapidly cycling population with a G1 -duration (TG1 ) of 20 h to 30 h; and there is a highly significant population of slowly cycling G1 -cells (G1σ ). However, no significant circadian variations were found in the number of these cells. 相似文献
204.
205.
206.
J. C. Zanuncio J. L. D. Saavedra H. N. Oliveira D. Degheele P. De Clercq 《Biocontrol Science and Technology》1996,6(4):619-626
The development of the Neotropical predatory pentatomid Brontocoris tabidus on an artificial diet based on beef meat and liver was evaluated. The predator showed significantly longer nymphal development and lower adult weights on this diet than when reared on pupae of the mealworm Tenebrio molitor. The survival of nymphs fed exclusively on the artificial diet was somewhat lower compared with feeding on T. molitor pupae. When B. tabidus was bred on this artificial diet during part of its nymphal period i.e. during the second; second and third; and second, third and fourth instars , and was subsequently returned to T. molitor pupae, the predator nymphs completed the nymphal stage with a developmental rate similar to that of nymphs fed on live prey throughout. The adults attained after switching from the artificial diet to live prey from the third and fourth instar onwards had similar weights to those in the control. Considering the relatively good results obtained with B. tabidus and other members of the pentatomid subfamily Asopinae, this meat-based diet may be a valuable alternative for use in the mass production of predatory pentatomids. 相似文献
207.
Pieter H. B. De Visser Willem G. Keltjens Günther R. Findenegg 《Trees - Structure and Function》1996,10(5):301-307
In a pot trial growth and transpiration of 3-year-old Douglas-fir seedlings on an acid, sandy soil was examined at a deficient
(30 kg N ha –
1 year –
1) and an excessive level (120 kg N ha –
1 year –
1) of NH4 application. Dissolved ammonium sulphate was applied to the pots weekly for two growing seasons. In half of the pots a complete
set of other nutrients was applied in optimal proportions to the applied nitrogen. Water supply was optimal and transpiration
was recorded. At the end of the second treatment season irrigation was stopped for 2 weeks during dry and sunny weather. Both
high application of NH4 and additional nutrients increased shoot growth and transpiration demand in the first treatment year. The root system was
smaller at higher N level and this reduced water uptake accordingly. In the second year the combination of high NH4
+ and additional nutrients affected root functioning predominantly due to salinity effects and this seriously decreased water
uptake capacity and shoot water potentials, finally resulting in tree death. Without addition of other nutrients the high
NH4
+ application resulted in a high degree of soil acidification, which damaged the roots, that showed a decrease in water uptake
capacity. At the low NH4 supply level soil acidification was lower, and root functioning was not affected, and the trees recovered quickly from the
imposed drought. Higher needle K and P status depressed transpiration rates at the low NH4 application rate.
Received: 9 January 1995 / Accepted: 18 September 1995 相似文献
208.
The skin of the bat wing in functionally unique among mammals: it serves as a major locomotor organ in addition to its protective and regulatory functions. We used tensile testing to investigate the mechanical capabilities of wing membrane skin, and compared stiffness, strength, load at failure, and energy absorption among specific wing regions and among a variety of bat taxa. We related these characteristics to the highly architectural fibrous supporting network of the wing membrane. We found that all material properties showed a strong anisotropy. In particular, wing membrane skin shows maximum stiffness and stregth parallel to the wing skeleton, and greatest extensibility parallel to the wing's trailing edge. We also found significant variation among wing regions. The uropatagium (tail membrane) supported the greatest load at failure, and the plagiopatagium (proximal wing membrane between laterl body wall and hand skeleton) is the weakest and most extensible part of the wing. We believe that the increased load bearing ability of the uropatagium relats to its key role in capture of insect prey, and that the great extensibility of the plagiopatagium promotes development of camber near the wing's centre of lift. In interspecific comparisons, energy absorpion and load to failure were greatest in Artibeus jamaicensis , the largest bat in our sample and the species with the highest wing loading, suggesting that wing loading may play a role in dictating the fuctional design of wing membranes. 相似文献
209.
Summary A new process for the production of small size dextran is developed in which dextran is produced by cultures of Leuconostoc mesenteroides in the presence of a partially constitutive mutant of Lipomyces starkeyi producing dextranase. Mixed cultures were examined by scanning electron microscopy with ruthenium to show the effects of the mixed culture on low molecular weight dextran (M.W. of 5,000 – 100,000) formation. The presence of the size variation in dextran was confirmed by gel permeation chromatography. 相似文献
210.