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101.
A case of somatostatin-producing pancreatic tumor associated with severe insulindependent diabetes mellitus and ketoacidotic
coma is reported. The tumor, a 10-cm expansile mass arising from the pancreatic tail of a 70-yr-old woman, was first detected
by ultrasonography, performed because of abdominal pain, and subsequently confirmed by computed tomography and fine-needle
tumor aspiration. Pathologic investigation showed a predominatly solid-trabecular structure with scattered microacini and
psammomatous bodies. A large proportion of tumor cells expressed somatostatin and/or calcitonin. Following resection of the
primary tumor and three peripancreatic lymph nodes with metastases, the patient recovered rapidly from her diabetic syndrome
and remained in substantially good health during a subsequent 8-yr follow-up period, without evidence of tumor recurrence. 相似文献
102.
Angelo Agostoni Bianca Marasini Marco Cicardi Giancarlo Martignoni Lilj Uziel Maurezio Pietrogrande 《Allergy》1978,33(4):216-221
Prophylactic treatment with antifibrinolytic agents, epsilon-aminocapriod and tranexamic acid, reduces the incidence and severits of attacks in patients with hereditary angioedema. Long-term ellectivenessor risk of antifibrinolytic agents has not been established. Sixteen patients needing continuous prophylaxis because of frequency and severity of attacks were treated with tranexamic acid. In four patients this treatment was ineffective and the drug was withdrawn after 2 months. A remission or reduction in the frequency or serverity of attacks was observed in 12 patients treated for a period ranging from 8 to 34 months. Hepatic tests and blood fibrinolytic activity were not influenced by long term oral treatment with tranexamic acid. 相似文献
103.
Biasco Guido Paganelli Gian Maria Psilogenis Mary Nazzari Marco Di Febo Giulio Siringo Sebastiano 《Inflammation research》1992,36(1):C88-C89
The effect on gastric epithelial cell proliferation of small doses of aspirin was evaluated in 9 healthy volunteers, with or without administration of sulglycotide, a sulfated glycopeptide with cytoprotective properties. Cell kinetics study was performed by incubation of gastric biopsies with bromodeoxyuridine (BrdU) and immunohistochemistry. A decrease of BrdU-labeling index and a shortening of the height of gastric columns were observed after treatment with aspirin and placebo. No variations were observed after treatment with aspirin and sulglycotide. A decrease of the epithelial cell renewal could be one of the damaging effects of aspirin on the gastric mucosa. The treatment with sulglycotide seems to be effective to prevent this alteration. 相似文献
104.
It is well known that the hypolipidemic drug ciprofibrate induces peroxisome proliferation in rodent liver, which in turn leads to the oxidative stress, and modifies some parameters related to cell proliferation and apoptosis. The administration of ciprofibrate to rats during the lactating period determined in their pups significant modifications in hepatic peroxisome enzyme activities, induction of the PPARalpha-target gene, Cyp4a10, and perturbation in cell proliferation and apoptosis, which affected the size of the liver. Moreover, this modification was associated to about two-fold induction of mRNA-PPARalpha. On the contrary, in the kidney, although a similar two-fold up-regulation of PPARalpha was detected, the induction of both peroxisomal enzyme activities and Cyp4a10 were weak, and no alterations were detected, neither in cell cycle nor in the size of the tissue. Our results indicate that the response to ciprofibrate is stronger in the liver than in the kidney of newborn rats. 相似文献
105.
Arcos D del Real RP Vallet-Regí M 《Journal of biomedical materials research. Part A》2003,65(1):71-78
Three biphasic materials have been synthesized from a magnetic glass-ceramic (Si-Ca-Fe) and a bioactive sol-gel glass (Si-P-Ca). The ratios of glass-ceramic:sol-gel glass used in this work were 1:1, 2:1, and 5:1. These materials show bioactive and magnetic properties and can be used as thermoseeds for hyperthermia treatment of bone tumors. The sol-gel glass content affects the textural properties of the glass-ceramic, giving rise to porosity, which plays a fundamental role in the formation of an apatite-like layer on the surface. On the other hand, as the sol-gel glass content increases, the magnetic properties change due to the diffusion of Fe ions to the glassy phases of the biphasic materials. The biphasic nature of these materials allows the changing of both properties, depending on the requirements of the patient. 相似文献
106.
107.
108.
Relating cistrons and functions in bacteriophage PM2 总被引:1,自引:0,他引:1
An approach to correlate functions with cistrons in bacteriophage PM2 is presented. Two of the temperature-sensitive mutants obtained differed from the wild type in heat sensitivity and four differed in host range. Comparison of the electrophoretic patterns of DNA from cells infected at the restrictive temperature with those obtained in wildtype infection revealed that viral DNA bands were absent with three additional mutants. Complementation analysis assigned the four host range mutants to cistron I and the three mutants defective in DNA synthesis to cistron IV. Recombination frequencies were used to locate cistrons III and IV on the partial genetic map of PM2. 相似文献
109.
Giuseppe A. Ramirez Valentina Canti Stefania Del Rosso Roberta Erra Lucia Moiola Marco Magnoni 《Autoimmunity》2020,53(1):21-27
AbstractBackground: Systemic lupus erythematosus (SLE) is associated with a constellation of complications affecting multiple organs, including neuropsychiatric manifestations (NPSLE) and ischaemic events, leading to increased long-term morbidity. Antiphospholipid antibodies (aPL) are a major determinant of vascular inflammation and thromboembolic risk. The diagnostic role of anti-phosphatidylserine/prothrombin (aPS/PT) antibodies in this setting is incompletely defined.Aim: To verify whether aPS/PT add to diagnostics and disease stratification in patients with SLE with or without other aPL.Methods: 131 consecutive patients were studied, including 20 patients with SLE and secondary antiphospholipid syndrome (APS). aPS/PT IgG and IgM were assessed through ELISA and patients were stratified based on the presence of other aPL, on their clinical and laboratory features at time of blood sampling and on their clinical history. Synthetic indices of disease activity, chronic damage and cardiovascular risk were calculated at time of venipuncture.Results: Fifty-one (38.9%) patients with SLE had aPS/PT and 15 (11.5%) patients had aPS/PT as the only aPL (aPS/PT-only). aPS/PT-only patients had a significantly higher prevalence of NPSLE than quadruple aPL-negative patients (p?=?.007). Patients with aPS/PT were more likely to have a history of ischaemia, thrombocytopenia and Libman–Sacks’ endocarditis. The presence of aPS/PT also associated with previous accrual of at least one damage item (p?=?.043), but had limited predictive values for damage progression in the short term.Conclusion: aPS/PT antibodies provide non-redundant information that could contribute to risk assessment and stratification of patients with SLE. 相似文献
110.
Transmissible spongiform encephalopathies (TSE) are attributed to the conversion of the cellular prion protein (PrP(c)) into an abnormal isoform (PrP(sc)). This can be caused by the invasion of living organisms by infectious particles, or be inherited due to mutations on the PrP(c) gene. One of the most intriguing problems of prion biology is the inability to generate the infectious agent in vitro. This argues strongly that other cellular proteins besides those added in test tubes or found in cellular preparations are necessary for infection. Despite recent progress in the understanding of prion pathology, the subcellular compartments in which the interaction and conversion of PrP(c) into PrP(sc) take place are still controversial. PrP(c) interacts with various macromolecules at the cell membrane, in endocytic compartments and in the secretory pathway, all of which may play specific roles in the internalisation of PrP(sc) and conversion of PrP(c). A specific interacting protein required for the propagation of prions was originally proposed as a prion receptor, and later referred to as a ligand, a cofactor, protein X, or a partner. However, current studies indicate that PrP(c) associates with multi-molecular complexes, which mediate a variety of functions in distinct cellular compartments. It is proposed that a deeper understanding of the mechanics of such interactions, coupled to a better knowledge of the corresponding signalling pathways and ensuing cellular responses, will have a major impact on the prevention and treatment of TSE. 相似文献