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1.
Over the past decade, because of the introduction and widespread availability of prostate-specific antigen determinations, carcinoma of the prostate that is localized and potentially curable has been diagnosed in an increasing number of men. Advances in surgical management with preservation of the neurovascular bundles, in addition to hormone therapy, have added to the success and improved quality of life of patients undergoing treatment. New forms of treatment (including laparoscopic prostatectomy and high-intensity focused ultrasound) are advances that are continuing to be developed and that may have a significant role in the management of this disease. With further investigation and technologic advancement, it is anticipated that more and more men with localized disease will be identified and cured, with preservation of sexual and urinary function.  相似文献   

2.
The main idea of the article is presentation of todays problem of gastric cancer diagnosis. Authors, supported by long-term experience of gastric cancer diagnostics, demonstrate the necessity of the return of traditional roentgenological method for it's diagnostics, along with endoscopic technique. In the first place it is determined by the increase of sclerotic and mixed forms. In the second place, it is associated by the change of gastric cancer primary localizations, supporting the need of active use of roentgen diagnostics for it's diagnosis. One of the important parts of the article consists of the author's attempt to change general opinion about insignificancy role of traditional roentgenological method for diagnosis of gastric cancer. Authors demonstrate modern techniques of traditional stomach roentgenology and firstly, it's digital development with CR-systems for the improvement of diagnosis of the intramural forms of carcinomas. In the initial stages it is obligatory to engage classical roentgenology with double contrast study and endoscopy as main equally important methods. The unfavourable situaition in the diagnosis of gastric cancer can be changed only with conjoint use of these two approaches. It is chiefly depends with the difficulties of endoscopic study of diffuse (endophytic) forms of gastric carcinoma. Authors separately underline the necessity of including specialists in roentgen diagnostics in the national project of modernization of roentgenological equipment in medical institutions.  相似文献   

3.
Secretory carcinoma diagnosed by aspiration biopsy cytology (ABC) disclosed many characteristic figures that were similar to a bunch of grapes, secondary mucous globular structures (MGSs) and clustered MGSs. The MGS was a unit structure of secretory carcinoma composed of a centrally located, small amount of mucus and two or more tumor cells covering it. Other findings were vacuolated cells and mucus in a clear background. The presence of the above findings, especially the "bunch of grapes" and related forms, were though to be essential findings in the cytologic differential diagnosis of secretory carcinoma by the ABC method. The origin of the characteristic features is discussed.  相似文献   

4.
The alpha-L-fucosidase isoenzyme pattern of mouse teratocarcinoma-derived cell lines was analyzed by isoelectric focusing and compared with the pattern of a mammary carcinoma as an example of a malignant somatic cell line. In addition, these isoenzyme patterns were compared with those of normal fetal and adult mouse tissues from an earlier study. In the normal early fetal and placental tissues as well as in embryonal carcinoma and yolk sac carcinoma cells the alpha-L-fucosidase activity is predominantly associated with basic forms of the enzyme. This embryonic pattern of alpha-L-fucosidase is characterized by one to three isoelectric forms of the enzyme with pI values ranging from 7 to 9.5 accounting for more than two-thirds of the total activity. In contrast, the mammary carcinoma pattern resembles adult somatic tissues and primarily expresses acidic enzymatic forms (which comprise approximately 80% of total activity). The somatic cell malignancies arising in retransplantable teratocarcinomas show varying isoenzyme patterns. Thus, a malignant fibrous histiocytoma expresses predominantly basic forms of the enzyme, whereas a leiomyosarcoma expresses approximately equal amounts of acidic and basic forms of the enzyme resembling in this respect late fetal or immature neonatal tissues. These findings show that the embryonal carcinoma and yolk sac carcinoma cells of the mouse express the embryonic isoenzyme pattern of alpha-L-fucosidase in contrast to malignant cells originating in somatic tissue, like mammary carcinoma, which express the adult pattern. Malignancies arising in somatic tissues of teratocarcinomas may retain the embryonic alpha-L-fucosidase phenotype or show a phenotype corresponding to late fetal or neonatal tissues in normal ontogeny.  相似文献   

5.
Ret/ptc2 is a constitutively active, oncogenic form of the c-Ret receptor tyrosine kinase. Like the other papillary thyroid carcinoma forms of Ret, Ret/ptc2 is activated through fusion of the Ret tyrosine kinase domain to the dimerization domain of another protein. Investigation of requirements for Ret/ptc2 mitogenic activity, using coexpression with dominant negative forms of Ras and Raf, indicated that these proteins are required for mitogenic signaling by Ret/ptc2. Because activation of Ras requires recruitment of Grb2 and SOS to the plasma membrane, the subcellular distribution of Ret/ptc2 was investigated, and it was found to localize to the cell periphery. This localization was mediated by association with Enigma via the Ret/ptc2 sequence containing tyrosine 586. Because Shc interacts with MEN2 forms of Ret, and because phosphorylation of Shc results in Grb2 recruitment and subsequent signaling through Ras and Raf, the potential interaction between Ret/ptc2 and Shc was investigated. The PTB domain of Shc also interacted with Ret/ptc2 at tyrosine 586, and this association resulted in tyrosine phosphorylation of Shc. Coexpression of chimeric proteins demonstrated that mitogenic signaling from Ret/ptc2 required both recruitment of Shc and subcellular localization by Enigma. Because Shc and Enigma interact with the same site on a Ret/ptc2 monomer, dimerization of Ret/ptc2 allows assembly of molecular complexes that are properly localized via Enigma and transmit mitogenic signals via Shc.  相似文献   

6.
弗林蛋白酶(Furin)是前体蛋白转化酶家族的重要成员之一,广泛存在于各种组织和细胞系中。Furin经过两次自剪切去掉前肽后具有生理活性,能够识别特定的氨基酸序列并在TGN中对多种前体蛋白进行加工。Furin的作用底物不仅包括神经肽和肽类激素,还包括许多生长因子、受体、血浆蛋白酶、基质金属蛋白酶及细菌外毒素等,具有重要的生物学功能。  相似文献   

7.
We present a case of 50 year-old man with feminizing adrenal carcinoma. He was admitted to the hospital because of weakness and one year history of gynecomastia and high blood pressure. Examinations revealed a large left adrenal mass and increased levels of estradiol. Patient underwent adrenalectomy and followed by mitotan therapy as the result of histopathological examination was adrenocortical carcinoma. One year after operation patient stays free from the recurrence of the disease and his estradiol, androstendion and DHEA levels are below the detection limits. We report this case because feminizing adrenal carcinoma is a very rare but serious disease and gynecomastia that could be its manifestation is quite frequent symptom in men's population and thus it could easily be missed. In every case of gynecomastia related to estradiol excess feminizing tumors of testis and adrenal gland should be ruled out.  相似文献   

8.
The evolution of the life cycle of brown seaweeds   总被引:2,自引:0,他引:2  
The brown seaweeds (Phaeophyta) are well-suited for testing theories of the evolution of the sexual alternation of haploid and diploid generations because of the great diversity of life cycles within the phylum. Three theories are investigated in this paper. (1) Diploid growth evolves because it has the effect of complementing deleterious recessive mutations. This is rejected because (a) ancestral haplonty is not a parsimonious inference from current phylogenies; (b) the exaggeration of diploid growth does not evolve in a comb-like fashion; (c) forms with predominantly haploid growth have evolved from smaller isomorphic ancestors; and (d) there is no correlation between haploid growth and monoecy. (2) Diploid growth evolves when gamete dimorphism leads to intense sexual selection, favouring the production of genetically diverse gametes through meiosis. This is rejected because diere is no correlation between the dominance of the diploid generation and the degree of gamete dimorphism. It is possible to show that gamete dimorphism itself has evolved in the Phaeophyta through the increase in size of the macrogamete in forms that have evolved larger sporophytes. (3) Microthalli become specialized as gametophytes because fusion is promoted by releasing gametes into the boundary layer; macrothalli become specialized as sporophytes because dispersal is promoted by releasing zoospores into the water column. This is consistent with the sexual and reproductive biology of Phaeophyta. The classic sexual cycle can then be interpreted as evolving from an asexual alternation of microthallus and macrothallus, governed largely by environmental factors, through selection for the appropriate association of ploidy with vegetative size. The exceptions to this general rule are forms in which gametes are released from macrothalli, where a different suite of sexual characters has evolved.  相似文献   

9.
ABSTRACT: The differences between invasive lobular and ductal carcinomas affect the diagnostic and therapeutic management for patients with breast cancer. In most cases, this can be accomplished because of distinct histomorphologic features. However, occasionally, this task may become quite difficult, in particular when dealing with the variants of infiltrating lobular carcinoma. Lobular carcinoma has been considered a variant of mucin-secreting carcinoma with only intracytoplasmic mucin. The presence of extracellular mucin is a feature of ductal carcinoma. Herein is presented a case of lobular carcinoma with extracellular and intracellular mucin in a 43-year-old female patient, and confirmed by immunohistochemistry. Up to the present, infiltrating lobular carcinoma displaying extracellular mucin has not been described in the literature except two case. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1839906067716744.  相似文献   

10.
11.
We have synthesized a 17‐mer peptide (ERα17p) that is issued from the hinge region of the estrogen receptor α and which activates the proliferation of breast carcinoma cells in steroid‐deprived conditions. In the present paper, we show that at a concentration of ~50 μM, it rapidly forms amyloid‐like fibrils with the assistance of electrostatic interactions and that at higher concentrations, it spontaneously forms a hydrogel. By using biophysical, spectral and rheological techniques, we have explored the structural, biophysical and mechanical characteristics of ERα17p with respect to fibril formation and gelation. Copyright © 2014 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   

12.
Glutaraldehyde possesses unique characteristics that render it one of the most effective protein crosslinking reagents. It can be present in at least 13 different forms depending on solution conditions such as pH, concentration, temperature, etc. Substantial literature is found concerning the use of glutaraldehyde for protein immobilization, yet there is no agreement about the main reactive species that participates in the crosslinking process because monomeric and polymeric forms are in equilibrium. Glutaraldehyde may react with proteins by several means such as aldol condensation or Michael-type addition, and we show here 8 different reactions for various aqueous forms of this reagent. As a result of these discrepancies and the unique characteristics of each enzyme, crosslinking procedures using glutaraldehyde are largely developed through empirical observation. The choice of the enzyme-glutaraldehyde ratio, as well as their final concentration, is critical because insolubilization of the enzyme must result in minimal distortion of its structure in order to retain catalytic activity. The purpose of this paper is to give an overview of glutaraldehyde as a crosslinking reagent by describing its structure and chemical properties in aqueous solution in an attempt to explain its high reactivity toward proteins, particularly as applied to the production of insoluble enzymes.  相似文献   

13.
A. Herbert 《Cytopathology》2000,11(6):471-479
Opinions about cervical screening in the UK tend to follow one of two negative lines of thought. The first is that cervical cancer is a rare disease, and too much time and effort are spent on screening. The second is that it has been relatively ineffective, since incidence of invasive carcinoma did not fall until the NHS Cervical Screening Programme (NHSCSP) was introduced in 1988, although it fell by 40% since then. This paper presents publicly available data to demonstrate that neither of these views is true. Registrations of invasive carcinoma of the uterine cervix and carcinoma in situ in England and Wales between 1971 and 1996 show that a substantially increased risk of disease in women born since 1940 has been reversed, almost certainly by greatly improved screening. Cervical carcinoma is now a rare disease because most cases are prevented before they become invasive, mostly by screening young women, aged 20-40, before the decade of life when symptomatic cervical carcinoma most frequently presents.  相似文献   

14.
Animal societies composed of breeders and non-breeders present a challenge to evolutionary theory because it is not immediately apparent how natural selection can preserve the genes that underlie non-breeding strategies. The clownfish Amphiprion percula forms groups composed of a breeding pair and 0-4 non-breeders. Non-breeders gain neither present direct, nor present indirect benefits from the association. To determine whether non-breeders obtain future direct benefits, I investigated the pattern of territory inheritance. I show that non-breeders stand to inherit the territory within which they reside. Moreover, they form a perfect queue for breeding positions; a queue from which nobody disperses and within which nobody contests. I suggest that queuing might be favoured by selection because it confers a higher probability of attaining breeding status than either dispersing or contesting. This study illustrates that, within animal societies, individuals may tolerate non-breeding positions solely because of their potential to realize benefits in the future.  相似文献   

15.
免疫酶技术鉴定 El Tor 型霍乱弧菌稳定 L 型   总被引:2,自引:0,他引:2  
细菌稳定 L 型的形态、培养特性以及生化反应常与原菌不同,其菌落在盐水中不能乳化,故不能通过玻片凝集测定其抗原。对于这种一时不能回复为原菌的 L 型很难进行鉴定。本文采用免疫酶技术对由鳝鱼和鲫鱼胆汁诱导的 El Tor 型霍乱弧菌稳定 L 型进行了鉴定。实验证明 L 型的细胞壁可有不同程度的缺失,稳定 L 型仍可能有少量“O”抗原存在。PAP 法比较敏感,即使少量抗原亦可以检出。  相似文献   

16.
Morphological plasticity can influence adaptive divergence when it affects fitness components such as foraging performance. We induced morphological variation in pumpkinseed sunfish (Lepomis gibbosus) ecomorphs and tested for effects on foraging performance. Young-of-year pumpkinseed sunfish from littoral and pelagic lake habitats were reared each on a 'specialist diet' representing their native habitat-specific prey, or a 'generalist diet' reflecting a combination of native and non-native prey. Specialist and generalist diets, respectively, induced divergent and intermediate body forms. Specialists had the highest capture success on their native prey whereas generalist forms were inferior. Specialists faced trade-offs across prey types. However, pelagic specialists also had the highest intake rate on both prey types suggesting that foraging trade-offs are relaxed when prey are abundant. This increases the likelihood of a resource polymorphism because the specialized pelagic form can be favoured by directional selection when prey are abundant and by diversifying selection when prey resources are restricted.  相似文献   

17.
A new two-dimensional ribosome crystal, having the tetragonal space group P42(1)2 (a = 593 A), has been grown from ribosome tetramers extracted from hypothermic chick embryos. It is of particular interest because of its larger size (up to 3 x 3 micron2) and greater stability compared to other related polymorphic forms, and because it can easily be grown in large amounts. X-ray diffraction shows the order in the crystal to extend to a resolution of at least 60 A. The crystalline ribosomes appear to contain a full complement of small and large ribosomal subunit proteins and an additional four proteins not characteristic of chick embryo polysomes.  相似文献   

18.
19.
We have continued our investigations of line lung carcinoma cells to understand the molecular basis of decreased expression of class I H-2 Ag and class I Ag induction with DMSO. We show that line 1, a murine lung carcinoma cell line, has low levels of class I Ag (H-2K, D, and L) because it is deficient in both class I and beta 2-microglobulin (B2M) RNA, and that these mRNA can be coordinately induced with DMSO. Evidence presented herein also shows that IFN-gamma can induce surface expression of class I Ag and suggests that it may act through a different mechanism than DMSO in inducing class I Ag. To further evaluate the regulation of class I expression, H-2Dp genes were transfected into line 1 cells. The transfected H-2 genes appear to be constitutively expressed at much higher levels than are the endogenous class I genes because surface expression of the foreign Dp Ag on the transfectants is elevated relative to the endogenous H-2d haplotype class I Ag. Both Dp surface expression and Dp mRNA are induced after treatment with DMSO. In all the Dp transfectants, we observed higher constitutive levels of class I mRNA as well as increased constitutive levels of endogenous B2M mRNA when compared to control or untransfected line 1 cells, however, we could not correlate these constitutive levels with Dp copy number. These results suggest that the regulation of class I and B2M genes is linked and that expression of class I genes can affect the expression of B2M genes.  相似文献   

20.
In developed countries, penile squamous cell carcinoma (SCC) account for < 1% of all malignancies in men. It is more frequent in rural populations of Africa, Asia and Latin America, where it may constitute nearly 10% of all carcinomas. In Paraguay, approximately 30-40 new cases are diagnosed per year. Different subtypes of penile carcinomas have been described. Most SCCs are of the usual type (60%). Less frequent variants include basaloid (10%), warty (10%), papillary (15%), verrucous (3%), sarcomatoid (4%) and adenosquamous (1%). Mixed forms also exist. Because there is a correlation between histologic subtype and biologic behavior, accurate subtyping is important. The prevalence of human papillomavirus (HPV) in invasive SCC is approximately 42%, with a strong association of HPV and basaloid and warty variants. Among the most important prognostic factors are histologic grade and depth of invasion. It is important for surgical pathologists to know the anatomy of the penis and possible routes of tumor spread because negative resection margins are crucial to avoid local recurrences. The most frequently involved margins are the urethra and periurethral tissues, including Buck's fascia. Probable precursor lesions of penile carcinoma include squamous hyperplasia, low and high grade squamous intraepithelial neoplasia and lichen sclerosus.  相似文献   

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