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11.
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   
12.
Summary The unpaired germarium of Dicrocoelium dendriticum contains many female germ cells at different stages of maturation and is enveloped by a fibrous basal lamina-like structure and a multilayered cytoplasmic sheath whose origins and functions are discussed. The maturation process of primary oocytes occurs completely within the prophase of the first meiotic division. It has been divided into three stages, as previously suggested for monogeneans. Stage I corresponds to oogonia and early oocytes which are located in the distal germinative area of the gonad. These cells are characterized by a high nucleo/cytoplasmic ratio and a poorly differentiated cytoplasm. Stage II corresponds to maturing oocytes grouped in the central area of the gonad and exhibiting long synaptonemal complexes and a prominent nucleolus. The main feature of cytoplasmic differentiation is the increase in the number of RER and Golgi complex which are involved in the production of small electron-dense granules. Stage III corresponds to mature oocytes located in the proximal area of the germarium near the origin of the oviduct. In this stage, the granules become regularly distributed in a monolayer in the peripheral ooplasm and make contact with the oolemma. They show a distinctive complex structure, are composed of proteins and glycoproteins and do not contain polyphenols. Their possible role as cortical granules is discussed in relation to chemical composition and previous studies on other Plathelminthes. Neither yolk globules nor glycogen are present in the oocytes.Abbreviations I oogonium and early oocyte - II growing oocyte - III mature oocyte - cg cortical granule - cs cytoplasmic sheath - db dense body - ecm extra cellular matrix - ER endoplasmic reticulum - fl fibrous extracellular layer - gc Golgi complex - m mitochondria - N nucleus - nu nucleolus - RER rough endoplasmic reticulum - sc synaptonemal complex  相似文献   
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14.
Projection of land use and land-cover change is highly uncertain yet drives critical estimates of carbon emissions, climate change, and food and bioenergy production. We use new, spatially explicit land availability data in conjunction with a model sensitivity analysis to estimate the effects of additional land protection on land use and land cover. The land availability data include protected land and agricultural suitability and is incorporated into the Moirai land data system for initializing the Global Change Analysis Model. Overall, decreasing land availability is relatively inefficient at preserving undeveloped land while having considerable regional land-use impacts. Current amounts of protected area have little effect on land and crop production estimates, but including the spatial distribution of unsuitable (i.e., unavailable) land dramatically shifts bioenergy production from high northern latitudes to the rest of the world, compared with uniform availability. This highlights the importance of spatial heterogeneity in understanding and managing land change. Approximately doubling the current protected area to emulate a 30% protected area target may avoid land conversion by 2050 of less than half the newly protected extent while reducing bioenergy feedstock land by 10.4% and cropland and grazed pasture by over 3%. Regional bioenergy land may be reduced (increased) by up to 46% (36%), cropland reduced by up to 61%, pasture reduced by up to 100%, and harvested forest reduced by up to 35%. Only a few regions show notable gains in some undeveloped land types of up to 36%. Half of the regions can reach the target using only unsuitable land, which would minimize impacts on agriculture but may not meet conservation goals. Rather than focusing on an area target, a more robust approach may be to carefully select newly protected land to meet well-defined conservation goals while minimizing impacts to agriculture.  相似文献   
15.
A complete series of terminally blocked, monodispersed homo-oligopeptides (to the pentamer level) from the sterically demanding, medium-ring alicyclic Cα,α-disubstituted glycine 1-aminocyclooctane-1-carb oxylic acid (Ac8c), and two Ala/Ac8c tripeptides, were synthesized by solution methods and fully characterized. The preferred conformation of all the oligopeptides was determined in deuterochloroform solution by IR absorption and 1H-NMR. The molecular structures of the amino acid derivative Z-Ac8c-OH, the dipeptide pBrBz- (Ac8c)2-OH and the tripeptide pBrBz-(Ac8c)3-OtBu were assessed in the crystal state by X-ray diffraction. Conformational energy computations were performed on the monopeptide Ac-Ac8c-NHMe. Taken together, the results obtained strongly support the view that the Ac8c residue is an effective β-turn and helix former. A comparison is also made with the conformational preferences of α-aminoisobutyric acid, the prototype of Cα, α-disubstituted glycines, and of the other members of the family of 1-aminocycloalkane-1-carboxylic acids (Acnc, with n=3, 5–7) investigated so far. The implications for the use of the Ac8c residue in peptide conformational design are considered.  相似文献   
16.
The ability of breast tumours to synthesize hormones is well recognized, and local production of sex steroids is thought to play a role in breast cancer growth. We measured the intratumour and circulating levels of testosterone, dihydrotestosterone (DHT) and oestradiol in 35 histologically confirmed carcinomatous mammary tissues obtained at breast surgery from 34 postmenopausal patients, age 50–85 years. Intra-tissue steroids were extracted with ethanol:acetone (1:1; v/v), defatted with 70% methanol in water, and extracted with ether. Steroids, from tissue and serum, were separated by partition chromatography on celite columns and were measured by RIA. Intratumour testosterone and DHT concentrations were significantly correlated, after the exclusion of an outlier (rs = 0.71; P = 0.0001). No association was found between oestradiol and either of the two androgens. Mean oestradiol and DHT concentrations were significantly higher in tissue than in blood (P = 0.0001). Mean testosterone levels in tissues did not significantly differ from those measured in blood. Our data suggest that at least a part of intratissue DHT is produced locally from testosterone. The meaning of high oestradiol and DHT levels in cancer tissue still needs to be defined.  相似文献   
17.
Plasmids S-a and Rts1 suppress the galactose-sensitive phenotype of galE mutants of Escherichia coli K-12, giving rise to both galactose-fermenting and nonfermenting strains. Fermenting strains produce normal inducible UDP-galactose epimerase. Plasmids extracted from either a fermenting or a nonfermenting strain are indistinguishable when examined by either measurements of length of relaxed circular molecules by electron microscopy or electrophoretic pattern of restriction endonuclease digestion products. The phenomenon could be explained by reversible recombination between a plasmid-borne epimerase gene and homologous chromosomal sequences.  相似文献   
18.
Summary Experiments designed to test the olfactory hypothesis of pigeon navigation by application of odorous substances to the birds' beaks and nostrils had shown until now variable results which have been interpreted differently. Using a new procedure, we were able to obtain consistent results. In each of the ten experiments performed, pigeons treated with -pinene were randomly oriented whereas control birds were not. Increase of homing time in experimental birds was also confirmed.This work was supported by a grant from the Consiglio Nazionale delle Ricerche.  相似文献   
19.
Amino acid composition of zein molecular components   总被引:1,自引:0,他引:1  
Zein extracted from maize endosperm has been fractionated into four polypeptide chains, having the following MWs 23 000, 21 000, 13 500 and 9600. By amino acid analysis the two smaller MW chains (representing 30% of total zeins) have been found to be zein-type molecules. These two chains are thought to be responsible for zein granule formation via -S-S- bridges. Zein is also highly heterogeneous in charge, and is resolved into at least 15 components, with pI's in the pH range 5–9. As demonstrated by amino acid analysis, part of this heterogeneity is due to spot mutations in some of the genes responsible for zein synthesis.  相似文献   
20.
Summary European populations of the turbellarianMesostoma ehrenbergii can produce two types of eggs according to a seasonal cycle. Subitaneous eggs (S eggs) are produced throughout the warm season and develop rapidly inside the parental uteri. They are meant to ensure a fast increase in the number of worms. Dormant eggs (D eggs) are produced during the warm season and are usually deposited in water at the death of the parent. They can hatch at the beginning of the next warm season and are, therefore, meant to ensure the survival of the population throughout the cold season, when adult worms are no longer present.S eggs are bounded by a thin, translucent covering which has a loose structure and is mainly proteinaceous in composition. These characteristics account for the functional role played by the S egg covering during embryonic development. The covering has, in fact, to be permeable to parental nutrients, and to keep pace, by stretching, with the enlargement of the embryo. By contrast, D eggs are bounded by a thick shell, presumably composed of a sclerotin, the precursors of which (polyphenols) are synthesized together with yolk in the vitelline cells. The shell has a smooth surface devoid of pores and has the function of isolating the developing D egg from the external environment.Supported by a grant from the Consiglio Nazionale della RicercheThe authors wish to thank Dr. P. Roach for his help in translating the paper  相似文献   
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