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91.
Salvatore Battaglia Giuseppe Barbolini Annibale R. Botticelli 《Virchows Archiv : an international journal of pathology》1979,382(3):245-259
Summary This study was performed in order to elucidate some of the problems of incidence, morphology and natural history concerned with Stage A prostatic cancer or prostatic microcarcinoma (PMC).The prostates of 100 patients, treated by subtotal prostatectomy for benign prostatic hyperplasia (BPH), were studied by comparing both routine and step-section techniques. The incidence of PMC was 41% by the former and 86% by the latter technique. Assessment of the size of PMC, as measured by the sum of the two main diameters, resulted in three groups: A1, A2, A3. The last of these may represent a frankly malignant condition, judged by size and the histological appearance. Radical prostatectomy is strongly suggested as appropriate therapy for this group.Supported in part by a Grant from the Ministry of Education (art. 286 T.U., 1977/78) 相似文献
92.
Recovery of the endogenous beta cell function in the NOD model of autoimmune diabetes 总被引:7,自引:0,他引:7
Zorina TD Subbotin VM Bertera S Alexander AM Haluszczak C Gambrell B Bottino R Styche AJ Trucco M 《Stem cells (Dayton, Ohio)》2003,21(4):377-388
In light of accumulating evidence that the endocrine pancreas has regenerative properties and that hematopoietic chimerism can abrogate destruction of beta cells in autoimmune diabetes, we addressed the question of whether recovery of physiologically adequate endogenous insulin regulation could be achieved in the nonobese diabetic (NOD) mice rendered allogeneic chimerae. Allogeneic bone marrow (BM) was transplanted into NOD mice at the preclinical and overtly clinical stages of the disease using lethal and nonlethal doses of radiation for recipient conditioning. Islets of Langerhans, syngeneic to the BM donors, were transplanted under kidney capsules of the overtly diabetic animals to sustain euglycemia for the time span required for recovery of the endogenous pancreas. Nephrectomies of the graft-bearing organs were performed 14 weeks later to confirm the restoration of endogenous insulin regulation. Reparative processes in the pancreata were assessed histologically and immunohistochemically. The level of chimerism in NOD recipients was evaluated by flow cytometric analysis. We have shown that as low as 1% of initial allogeneic chimerism can reverse the diabetogenic processes in islets of Langerhans in prediabetic NOD mice, and that restoration of endogenous beta cell function to physiologically sufficient levels is achievable even if the allogeneic BM transplantation is performed after the clinical onset of diabetes. If the same pattern of islet regeneration were shown in humans, induction of an autoimmunity-free status by establishment of a low level of chimerism, or other alternative means, might become a new therapy for type 1 diabetes. 相似文献
93.
Battaglia C; Artini PG; Giulini S; Salvatori M; Maxia N; Petraglia F; Volpe A 《Human reproduction (Oxford, England)》1997,12(11):2477-2482
The objective of this study was to evaluate the Doppler flow variations
which occur following the use of different protocols of ovarian stimulation
in an IVF programme, and to investigate the thromboxane production by
cultured endometrial cells and its influence on embryo implantation. A
total of 60 patients underwent three different ovarian stimulation
protocols: long gonadotrophin-releasing hormone agonist (GnRH-a), short
GnRH-a and no GnRH-a. Transvaginal ultrasonography and colour Doppler
analysis were performed before and during the treatment. On the day that
the Doppler examination took place, luteinizing hormone, follicle
stimulating hormone, plasma oestradiol and thromboxane concentrations were
assayed. On the day of oocyte retrieval, endometrial cells were collected
and cultured, and their thromboxane production evaluated. No significant
differences in hormonal, ultrasonographic or Doppler parameters were
observed between the three groups. Ten out of 56 patients who had a
successful embryo transfer became pregnant. In the group of pregnant women
the pulsatility index values of both uterine and spiral arteries was lower
than in non-pregnant patients, and was associated with significantly lower
thromboxane concentrations from cultured endometrial cells. It is concluded
that thromboxane plays a role in embryo implantation, and that Doppler flow
analysis of uterine and spiral arteries in infertile patients may be
important in the management of ovarian stimulation.
相似文献
94.
95.
Cova L Ratti A Volta M Fogh I Cardin V Corbo M Silani V 《Stem cells and development》2004,13(1):121-131
In the past few years research on stem cells has exploded as a tool to develop potential therapies to treat incurable neurodegenerative diseases. Stem cell transplantation has been effective in several animal models, but the underlying restorative mechanisms are still unknown. Several events such as cell fusion, neurotrophic factor release, endogenous stem cell proliferation, and transdifferentiation (adult cell acquisition of new unexpected identities) may explain therapeutic success, in addition to replacement of lost cells. This issue needs to be clarified further to maximize the potential for effective therapies. Preliminary stem transplantation trials have already been performed for some neurodegenerative diseases. There is no effective pharmacological treatment for amyotrophic lateral sclerosis, but recent preliminary data both in experimental and clinical settings have targeted it as an ideal candidate disease for the development of stem cell therapy in humans. This review summarizes recent advances gained in stem cell research applied to neurodegenerative diseases with a special emphasis to the criticisms put forward. 相似文献
96.
97.
Macchi C Popolizio A Casamorata F Bicchi S Pieroni A Molino Lova R Miniati B Gulisano M Catini C Conti AA Gensini GF 《Italian journal of anatomy and embryology = Archivio italiano di anatomia ed embriologia》2002,107(2):93-97
Fifty-four subjects, aged between 20 and 35 years, divided into two subgroups, respectively 30 healthy subjects (17 males and 13 females) and 24 subjects with "gonalgia sine materia" (13 males and 11 females) underwent isokinetic exercise test in order to compare their dominant limb with the not dominant one as regard as the strength of extensor and flexor muscles of the knee. No statistically significant difference was found in any of the studied parameters in the comparison between the dominant limb and the not dominant one, both within the subgroup of healthy subjects and within the subgroup of subjects with "gonalgia sine materia". Authors conclude that psychological features may play a preeminent role in the genesis, as well as in the maintenance of "gonalgia sine materia", thus confirming previous data available in medical literature. 相似文献
98.
Changes in E-cadherin immunoreactivity in the adenoma-carcinoma sequence of the large bowel 总被引:7,自引:0,他引:7
Giuseppe Gagliardi Olcay Kandemir Michelle Guida Serena Benvestito Gordon W. H. Stamp Massimo Pignatelli Theo G. M. Ruers Irving S. Benjamin John M. A Northover Ian C. Talbot 《Virchows Archiv : an international journal of pathology》1995,426(2):149-154
We have used an avidin-biotin immunoperoxidase technique to localise epithelial cadherin (E-cadherin), a calcium-dependent cell-cell adhesion molecule, in 107 paraffin-embedded sections from 93 patients consisting of 24 with colorectal adenoma, 55 with rectal carcinoma and 14 with liver metastases. The corresponding primary colorectal tumours were also studied in these cases. E-cadherin was expressed by normal colorectal epithelial cells with typical membranous staining at the intercellular junctions. Loss of normal membranous E-cadherin expression and presence of cytoplasmic staining were found frequently in adenomas larger than 1 cm (P<0.01), with high grade dysplasia and villous histology (P<0.01). In primary rectal cancers, loss of membranous expression correlated with high tumour grade. No correlation was seen with Dukes and Jass stage, local extramural spread and 5-year recurrence rate. Complete loss of membranous E-cadherin immunoreactivity was seen in 7/14 (50%) liver metastases in which 6/7 (86%) showed intense membranous E-cadherin immunoreactivity in the corresponding primary tumour. Our data indicate that changes in E-cadherin immunoreactivity and cellular localisation correlate with size, severe dysplasia in adenomas and tumour grade in carcinomas. However, there seems to be no correlation between loss of membranous E-cadherin immunoreactivity and the invasive and metastatic potential of the carcinomas. 相似文献
99.
Cell proliferation in breast cancer is a major determinant of clinical outcome in node-positive but not in node-negative patients. 总被引:2,自引:0,他引:2
Davide Treré Claudio Ceccarelli Mario Migaldi Donatella Santini Mario Taffurelli Elena Tosti Pasquale Chieco Massimo Derenzini 《Applied immunohistochemistry & molecular morphology》2006,14(3):314-323
The growth rate of a tumor cell population depends on two major factors: the percentage of proliferating cells (cell growth fraction) and the rapidity of their duplication (cell proliferation rate). The authors evaluated the prognostic and predictive value of both kinetics parameters in a large series of breast cancer patients (n=504). The cell growth fraction was determined by MIB-1 immunostaining, the cell proliferation rate by AgNOR analysis. Ki-67 LI (labeling index) and AgNOR area were significantly associated with histotype, histologic grade, tumor size, estrogen/progesterone receptor status, patient age, and lymph node involvement (P<0.005). In the entire series of patients, both kinetics variables were significantly and independently associated with the clinical outcome, but their prognostic relevance was quite different when node-negative and node-positive patients were considered separately. Although in node-positive patients Ki-67 LI and AgNOR area were the unique independent predictors of disease-free and overall survival, they were excluded by the multivariate Cox model in node-negative patients, where only tumor size and estrogen receptor status retained a significant P-value. These results show that in breast carcinoma the cell growth fraction and the cell proliferation rate have a different prognostic impact with respect to the lymph node status and are major determinants of clinical outcome in node-positive patients only. Within this subgroup, the rapidity of cell proliferation as assessed by AgNOR analysis also served as a sensitive predictor of the response to adjuvant treatments. 相似文献
100.
Paolo Leoncini Marcella Cintorino Carla Vindigni Lorenzo Leoncini Doretta Armellini Massimo Bugnoli Omar Skalli Giulio Gabbiani 《Virchows Archiv : an international journal of pathology》1988,412(4):329-337
Summary We have evaluated by means of immunocytochemistry the distribution of various cytoskeletal and contractile proteins (cytokeratins, vimentin, desmin and -smooth muscle actin) in 23 salivary or lacrimal gland primary tumours (15 pleomorphic adenomas and 8 carcinomas in pleomorphic adenoma), one third of which contained areas of normal gland. Normal epithelial luminal cells were stained by cytokeratin antibodies with a general specificity, while myoepithelial cells were selectively stained by a monoclonal antibody (SK2-27) reacting in immunoblots with cytokeratin polypeptides 14, 16 and 17, according to the classification of Moll et al. (1982) and by an antibody directed against -smooth muscle actin (Skalli et al. 1986). In pleomorphic adenomas, both epithelial and myoepithelial cells displayed typical topographic distributions; moreover, myoepithelial cells showed two distinct cytoskeletal phenotypes. These findings could account in part for the heterogeneity of aspects observed in this tumour. In carcinomas, malignant cells were always positive to cytokeratin antibodies with general specificity and myoepithelial cells were absent as judged by anticytokeratin SK2-27 and anti--smooth muscle actin immunostainings. However, interestingly, there was in all cases a strong positivity for -smooth muscle actin in stromal cells, similarly to what has previously been described for mammary carcinoma (Skalli et al. 1986). Our findings may be useful for the interpretation of the histogenesis of salivary and lacrimal tumour and stromal cells. 相似文献