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31.
As conventional treatments are unsuccessful, the survival rate of stage D3 prostate cancer patients is poor. Reports have suggested the existence of humoral and cell-mediated immunity (CMI) against prostate cancer tumour-associated antigens (TAA). These observations prompted us to treat stage D3 prostate cancer patients with an in vitro produced transfer factor (TF) able to transfer, in vitro and in vivo, CMI against bladder and prostate TAA. Fifty patients entered this study and received one intramuscular injection of 2–5 units of specific TF monthly. Follow-up, ranging from 1 to 9 years, showed that complete remission was achieved in 2 patients, partial remission in 6, and no progression of metastatic disease in 14. The median survival was 126 weeks, higher than the survival rates reported in the literature for patients of the same stage.  相似文献   
32.
The microsomal epoxide hydrolase (mEH)-catalyzed hydrolysis of cis-4,4′–dimethylstilbene oxide ( 1a ), cis-4,4′-diethylstilbene oxide ( 1b ), cis-4,4′-diisopropylstilbene oxide ( 1c ), and cis-4,4′-dichlorostilbene oxide ( 1d ) have been investigated using rabbit liver microsomal preparations. The kinetic parameters, Km and Vmax, and the absolute stereochemistry of the reactions have been determined and compared with those of cis-stilbene oxide ( 1e ). All epoxides 1a – d are hydrolyzed by mEH with high product enantioselectivity to give (R,R)-(+)-diols with ee ≥ 90%. The presence of the substituents on the phenyl rings markedly reduces the rates of mEH catalyzed hydrolysis with respect to cis-stilbene oxide, by increasing Km and reducing Vmax in the cases of 1a , 1b , and 1d , or reducing only the Vmax in the case of 1c . The very low Vmax, together with a persistent ability to fit into the mEH active site, make all these epoxides, and particularly 1c , inhibitors of cis-stilbene oxide hydrolysis. The kinetic and stereochemical results are interpreted on the basis of the proposed topology of the mEH active site. © 1994 Wiley-Liss, Inc.  相似文献   
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This study aimed to explore the 24-h patterns of stroke volume, cardiac output, and peripheral vascular resistance along with other correlated variables, such as left ventricular ejection time, ejection velocity index, thoracic fluid index, heart rate, and blood pressure. The study was performed on 12 clinically healthy subjects by means of a noninvasive beat-to-beat monitoring using the thoracic electric bioimpedance technique associated with the automated sphygmomano-metric recording. Time data series were analyzed by means of chronobiological procedures. The results documented the occurrence of a circadian rhythm for all the variables investigated, giving relevance to the beat-to-beat bioperiodicity of cardiac output and peripheral vascular resistance. Temporal quantification of the investigated variables may be useful for a better insight of the chronophysiology of the cardiovascular apparatus.  相似文献   
35.
Parasitic red algae are an interesting system for investigating the genetic changes that occur in parasites. These parasites have evolved independently multiple times within the red algae. The functional loss of plastid genomes can be investigated in these multiple independent examples, and fine-scale patterns may be discerned. The only plastid genomes from red algal parasites known so far are highly reduced and missing almost all photosynthetic genes. Our study assembled and annotated plastid genomes from the parasites Janczewskia tasmanica and its two Laurencia host species (Laurencia elata and one unidentified Laurencia sp. A25) from Australia and Janczewskia verruciformis, its host species (Laurencia catarinensis), and the closest known free-living relative (Laurencia obtusa) from the Canary Islands (Spain). For the first time we show parasitic red algal plastid genomes that are similar in size and gene content to free-living host species without any gene loss or genome reduction. The only exception was two pseudogenes (moeB and ycf46) found in the plastid genome of both isolates of J. tasmanica, indicating potential for future loss of these genes. Further comparative analyses with the three highly reduced plastid genomes showed possible gene loss patterns, in which photosynthetic gene categories were lost followed by other gene categories. Phylogenetic analyses did not confirm monophyly of Janczewskia, and the genus was subsumed into Laurencia. Further investigations will determine if any convergent small-scale patterns of gene loss exist in parasitic red algae and how these are applicable to other parasitic systems.  相似文献   
36.
Treatment with VP-16 (1-50 μM) or excess thymidine (5 mM) caused a block of L cells at different steps in their progression through the replicative cycle. The arrest was followed by an asynchronous process of cell death that conformed to criteria for apoptosis. Careful monitoring of this process in the whole cell population by flow cytometry showed a virtual absence of necrosis, an increase in side light scattering, followed by the occurrence of a population with subdiploid DNA fluorescence as well as reduced forward and side light seattering. The development of apoptosis required sufficient time and adequate ion gradients in the cells. By the combined use of flow cytometry and fluorescence microscopy data were obtained suggesting that (i) intracellular free Ca2+ and pH and/or their drug-induced alterations had to be adequately controlled for the apoptotic process to evolve; (ii) mitochondria were compromised earlier than the plasma membrane or lysosomes; and (iii) K+ extrusion possibly played a role in the final loss of cell volume. Interfering with the control of ion gradients and/or their changes in drug-treated cells resulted in cell death by necrosis.  相似文献   
37.
Canine distemper virus (CDV), a lymphotropic and neurotropic negative-stranded RNA virus of the Morbillivirus genus, causes a life-threatening disease in several carnivores, including domestic dogs. To identify the cellular receptor(s) involved in the uptake of CDV by susceptible cells, we isolated a monoclonal antibody (MAb K41) which binds to the cell surface and inhibits the CDV infection of several cell lines from various species. Pretreatment of cells with MAb K41 reduces the number of infectious centers and the size of the syncytia. Using affinity chromatography with MAb K41, we purified from HeLa and Vero cell extracts a 26-kDa protein which contained the amino acid sequence TKDEPQRETLK of human CD9, a member of the tetraspan transmembrane or transmembrane 4 superfamily of cell surface proteins. Transfection of NIH 3T3 or MDBK cells with a CD9 expression plasmid rendered these cells permissive for viral infection and raised virus production by a factor of 10 to 100. The mechanism involved is still unclear, since we were unable to detect direct binding of CDV to CD9 by using immunoprecipitation and a virus overlay protein binding assay. These findings indicate that human CD9 and its homologs in other species are necessary factors for the uptake of CDV by target cells, the formation of syncytia, and the production of progeny virus.  相似文献   
38.
Times of pollination of different taxa in the atmosphere of Perugia (Central Italy) over an 11-year period (1982–1992) were recorded and analysed by means of a 7-day volumetric Hirst-type pollen trap. For some taxa, the pollination period varied from year to year from a chronological and/or quantitative point of view. Several taxa showed a linkage in their starting dates of pollination. Knowledge of this kind of linkage allows us to build a forecasting model.  相似文献   
39.
Giuseppe Paradies 《BBA》1984,766(2):446-450
The binding of α-cyanocinnamate to rat-heart mitochondrial membrane was investigated using α-cyano[14C]cinnamate. The binding was correlated to the inhibition of pyruvate transport. The results obtained demonstrate that both these functions reach saturation at the same titre of the inhibitor. Quantitative parameters of α-cyano[14C]cinnamate binding have been determined. The binding can be prevented by pyruvate and other substrates of the carrier but not by acetate. Pyruvate decreases the affinity of α-cyanocinnamate binding, leaving the maximum number of binding unchanged. It is concluded that rat-heart mitochondria contain a specific site at which α-cyanocinnamate binds which is directly involved in the inhibition of pyruvate transport.  相似文献   
40.
From the aerial part of Teucrium chamaedrys a new neo-clerodane diterpenoid, dihydroteugin, has been isolated, besides the previously known diterpenoids teucrin A and teugin. The structure of dihydroteugin, (12S)-15,16-epoxy-2β,6β-dihydroxy-neo-cleroda-13(16), 14-diene-18,19:20,12-diolide, was established by chemical and spectroscopic means and by partial synthesis from teugin.  相似文献   
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