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1.
Malignant islet cell tumors are commonly treated with surgical resection. Chemotherapy is reserved for residual, unresectable, or metastatic disease. The role for radiotherapy has not been clearly defined. This article describes three cases of advanced islet cell tumors treated effectively with radiotherapy. This experience, in addition to that from other published reports, suggests that radiotherapy is a useful mode for treating advanced islet cell carcinoma. 相似文献
2.
Upregulation of epidermal growth factor receptor induced by alpha-interferon in human epidermoid cancer cells 总被引:2,自引:0,他引:2
A Budillon P Tagliaferri M Caraglia M R Torrisi N Normanno S Iacobelli G Palmieri M P Stoppelli L Frati A R Bianco 《Cancer research》1991,51(4):1294-1299
Unregulated or increased expression of epidermal growth factor receptor (EGF-R) is a common event in neoplastic transformation; modulation of such a receptor by physiological agents could be, therefore, of clinical interest. We have studied the binding ability, the availability at cell surface, and the synthesis of EGF-R in the A431 and KB human epidermoid cancer cell lines after treatment with recombinant alpha-interferon (IFN-alpha). After 48 h of treatment, IFN-alpha induces, in both cell lines, growth inhibition and enhances class I major histocompatibility HLA complex expression, which is a common marker of IFN action. [125I]EGF total binding assessed after 48 h of treatment with IFN-alpha shows a dose-dependent upregulation of EGF-R binding capacity. Saturation plots of the binding data show that IFN-alpha treatment does not dramatically alter the affinity of the EGF-R and indicate that IFN-alpha only increases the number of low affinity receptors. We show that this effect is due to a specific increase in the synthesis of the receptor protein, as assessed by immunoprecipitation of [35S]methionine-labeled cell extracts. Electron microscopy analysis has confirmed an increase of EGF-R proteins at cell surface without major changes in the morphology of the cells. Taken together, these results indicate that IFN-alpha consistently induces both the binding capacity and the synthesis of EGF-R in human epidermoid cancer cells and suggest the use of such a mechanism for new anticancer therapies. 相似文献
3.
Emilio Bombardieri Antonia Martinetti Rosalba Miceli Luigi Mariani Maria Rita Castellani Ettore Seregni 《European journal of nuclear medicine and molecular imaging》1997,24(11):1349-1355
Bone scintigraphy plays a major role in the diagnosis of bone metastases. The clinical utility of new biochemical markers
of bone metabolism has recently been investigated in various bone diseases. This study evaluated the role of some bone metabolism
markers in comparison with bone scan in the follow-up of breast cancer patients. We studied 149 patients with breast cancer,
33 (22%) of whom had bone metastases. IRMAs were used for the evaluation of blood levels of osteocalcin, bone alkaline phosphatase
(BAP), the C-terminal propeptide of type I procollagen and the C-terminal cross-linked telopeptide of type I collagen (ICTP).
Multivariate regression analysis showed that menopausal status (P=0.007) and metastatic bone lesions (P=0.001) affected bone marker levels. When considering post-menopausal women, the only subset in which bone metabolism marker
behaviour could be reliably investigated, we found a high degree of overlap in marker distribution for scan-positive and scan-negative
patients. Discrimination between scan-negative and scan-positive patients based on the above markers, taken singly or jointly,
was assessed by means of logistic discriminant analysis. The best discrimination was achieved with BAP, closely followed by
ICTP. BAP and ICTP together gave a slight improvement over the use of the two markers separately. However, even in this case
the degree of discrimination was poor and its clinical utility was limited. In fact, to achieve a specificity of 95%, the
sensitivity of the test was about 20%; conversely, with a sensitivity of 95%, the specificity was below 10%. In conclusion,
based on our findings, we believe that blood levels of the investigated markers cannot replace bone scintigraphy in the follow-up
of breast cancer patients for the early detection of bone metastases.
Received 14 April and in revised form 5 July 1997 相似文献
4.
Thirteen patients with clinical or subclinical retinal detachments were treated with photocoagulation with the aid of a device for scleral depression and the three mirror contact lens. The Eisner cone has proven helpful in achieving clinically white retinal burns at the margins of retinal breaks by displacing subretinal fluid at the time of treatment. Patients selected for treatment had adequate pigmentation for a good photocoagulation response, nearly clear ocular media, and minimal vitreo retinal traction. Extent of retinal detachment was not a determinant, but minimal retinal elevation at break locations proved beneficial. No immediate flattening or adhesion of the retina was seen on release of scleral depression at the time of photocoagulation. White clinical burns remained visible. In 12 of 13 patients the retina was in apposition to the retinal pigment epithelium around the breaks at the first post-treatment examination. The remaining subretinal fluid absorbed in even the most extensive detachment in 2 weeks. One patient with multiple breaks at the equator failed to respond to this technique and required a scleral buckle. 相似文献
5.
6.
The ultrastructure of the myoneural junctions in the body wall muscles has been studied in Branchiobdella pentodonta Whit. A single junctional type has been found. Within the terminal axon there are two types of vesicles, which differ in number, size and electron opacity. The junctional gap contains the basement membrane. The post-junctional membrane displays concave patches on which slender projections arising from the outer lamina of the sarcolemma extend into the junctional gap. These concave patches overlie a cytoplasmic lamina made up of electron dense material. 相似文献
7.
Mazzanti L Cicognani A Baldazzi L Bergamaschi R Scarano E Strocchi S Nicoletti A Mencarelli F Pittalis M Forabosco A Cacciari E 《American journal of medical genetics. Part A》2005,135(2):150-154
The identification of Y-chromosome material is important in females with Ullrich-Turner syndrome (UTS) due to the risk of developing gonadoblastoma or other gonadal tumors. There is controversy regarding the frequency of the Y-chromosome-derived material and the occurrence of gonadoblastoma in these patients. The aim of our study was to evaluate a large number of patients with UTS, followed before and during the pubertal age for the prevalence of Y-chromosome derived material, the occurrence of gonadoblastoma, and the incidence of possible neoplastic degeneration. An unselected series of 171 patients with UTS (1-34 years old), diagnosed cytogenetically, was studied for Y-chromosome markers (SRY and Y-centromeric DYZ3 repeats). The follow-up was of 2-22 years; 101 of these patients were followed during pubertal age. Y-chromosome material was found in 14 patients (8%): 12 of these were gonadectomized (2.8-25.9 years). A gonadoblastoma was detected in four patients under 16 years of age: in two, Y-material was detected only at molecular analysis (at conventional cytogenetic analysis, one was included in the 45,X group and one in the X + mar group) and one had also an immature teratoma and an endodermal sinus carcinoma. The prevalence of gonadoblastoma in our series of gonadectomized UTS patients with Y-positive material was of 33.3% (4/12). Our data suggest that the age of appearance and the possibility of malignant degeneration of gonadoblastoma can occur early in life. These patients, in particular those with 45,X or a marker chromosome may benefit from molecular screening to detect the presence of Y-chromosome material; PCR is a rapid and inexpensive technique. At the moment, laparoscopy and preventive gonadectomy performed as soon as possible remain the procedures of choice for patients with UTS, when Y-chromosome has been identified, as we are still unable to predict a future malignant evolution of gonadoblastoma. 相似文献
8.
Urzì F Iannello A Torrisi A Foti P Mortellaro NF Cavallaro M 《Italian journal of anatomy and embryology = Archivio italiano di anatomia ed embriologia》2003,108(2):83-117
The pterion is one of the most interesting bone meeting points in craniofacial osteology and its complex morphology derives from the fact that is the contact point of the facial skeletal elements, skull base and calvarium. Knowledge of its peculiar morphology is mandatory for the pterional approach used in microsurgery and surgery. The Authors studied 506 adult, human skulls where the pterion was accurately reconstructed on polyethylene sheets. They report their data on the morphological analysis and classify the forms. They focussed their attention on the presence of wormian bones at the level of the sphenoparietal suture, on the peculiar existing morphology and reviewed the literature on these classifications. The Authors also evaluated the length of the sphenoparietal suture, the minimum gap between the frontal and temporal, the influence of pteric bones on pterion variability and any correlations between measurements and cranial indexes. 相似文献
9.
Mazzanti L Cacciari E Cicognani A Bergamaschi R Scarano E Forabosco A 《American journal of medical genetics. Part A》2003,(3):279-286
We present three children with short stature, the same facial phenotype, macrocephaly, enlarged cerebral spinal fluid spaces, short neck with redundant skin, severe GH deficiency, mild psychomotor delay with attention deficit/hyperactivity disorder (ADHD), mild dilatation of the pulmonary root in two of them, and a unique combination of ectodermal abnormalities. Their appearance, not completely typical of Noonan syndrome, the behavioral phenotype, GH deficiency, darkly pigmented and hairless skin, and the unusual aspect of the hair, defined as loose anagen hair syndrome did not fit any known condition. We postulate that these children may represent a distinct, previously unreported syndrome that we would name "Noonan-like syndrome with loose anagen hair". 相似文献
10.
Torrisi L Visco AM Campo N Rizzo D Bombara A 《Bio-medical materials and engineering》2004,14(3):251-261
The significant wear of the UHMWPE bearings of explanted knee prostheses is produced mainly by micrometric debris ("third-body" wear) that diffuse toward the mobile metal-polymer interface. Here debris is crushed during the movement producing scratches in the metal and in the polymeric surfaces. Mechanical stress and the biological effects change the physical polymeric properties. In order to evaluate the area of UHMWE bearings submitted to high load stresses, in this work physical investigations are performed on the explanted knee prosthesis. Particularly, the roughness profile analysis (RPA) and the micro-hardness measurements (MHM) resulted suitable for the localisation of the mechanical and biological wear area. In the stressed zone, surface treatments could be applied in order to improve the mechanical resistance of the polymeric material. Particularly, the ion implantation with heavy ions is proposed to enhance the polymeric wear resistance. The Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectrometry (EDX) and Infrared absorption spectroscopy (FTIR) techniques were also applied and results discussed. 相似文献