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排序方式: 共有623条查询结果,搜索用时 15 毫秒
81.
Dr. John H. Landor MD Blair R. Behringer Robert A. Wild AB 《Digestive diseases and sciences》1970,15(7):633-636
Bile was excluded from the gastrointestinal tract of 5 dogs with Heidenhain pouches by total external biliary fistulas. After a major portion of the jejunum and the ileum was resected Heidenhain pouch secretions increased in all instances. The results indicate that the increase in gastric secretion which regularly follows small-bowel resection is independent of the presence or absence of bile in the gastrointestinal tract.Supported by Grant AM-7750 from the US Public Health Service.The opinions expressed in this publication are those of the authors and not necessarily those of the US Air Force Medical Service. 相似文献
82.
Alessandra Cirillo Anna Di Salle Orsolina Petillo Mariarosa AB Melone Giovanna Grimaldi Alfredo Bellotti Giovanni Torelli Maria Serena de’ Santi Giovanna Cantatore Alfredo Marinelli Umberto Galderisi Gianfranco Peluso 《Cancer biology & therapy》2014,15(6):735-741
The diagnosis of glioblastoma is still based on tumor histology, but emerging molecular diagnosis is becoming an important part of glioblastoma classification.
Besides the well-known cell cycle-related circuitries that are associated with glioblastoma onset and development, new insights may be derived by looking at pathways involved in regulation of epigenetic phenomena and cellular metabolism, which may both be highly deregulated in cancer cells.
We evaluated if in glioblastoma patients the high grade of malignancy could be associated with aberrant expression of some genes involved in regulation of epigenetic phenomena and lipid metabolism. We measured the mRNA levels of ZFP57, TRIM28, CPT1A, CPT1B, and CPT1C in a cohort of 80 patients divided in two groups: grade II and grade IV. We evidenced that high grade glioblastoma is associated with increased level of ZFP57, a protein involved in gene imprinting, and aberrant expression of CPT1A and CPT1C, regulators of fatty acid oxidation.
Our study may pave the way to identify new markers that could be potentially useful for diagnosis and/or prognosis of glioblastoma. 相似文献
83.
Corticosteroids have the ability to suppress the production of growth factors and cytokines and are thus implicated in the negative regulation of hematopoiesis. We have shown that the corticosteroids, prednisolone and dexamethasone, were able to effectively protect progenitor cells in four strains of mice against cell-cycle-specific antimetabolic chemotherapy agents. The highest levels of protection against 5-fluorouracil (FU; 200 mg/kg) were achieved when two or three intraperitoneal injections of dexamethasone were administered between - 7 and +3 hours at a dose of 7.5 mg/kg/injection (optimal dose) or by continuous infusion between -4 and +20 hours. This protective effect is manifested as an increase in the number of high proliferative potential colony-forming cells that survive in the bone marrow 3 days after treatment with FU from between 0.5% and 11% to between 10% and 34% of normal. The bone marrow progenitors and blood cell numbers return to normal from 3 to 5 days and 1 to 2 days earlier, respectively. Less dexamethasone than prednisolone is required to give an equivalent protective effect, which is consistent with their anti-inflammatory potency. These findings are further evidence of the negative regulatory role played by corticosteroids, and indicate that the treatment schedules of corticosteroids during cancer therapy need to be reexamined to obtain the maximum benefit from their use. 相似文献
84.
Deisseroth AB; Zu Z; Claxton D; Hanania EG; Fu S; Ellerson D; Goldberg L; Thomas M; Janicek K; Anderson WF 《Blood》1994,83(10):3068-3076
Relapse after autologous bone marrow transplantation for chronic myelogenous leukemia (CML) can be due either to the persistence of leukemia cells in systemic tissues following preparative therapy, or due to the persistence of leukemia cells in the autologous marrow used to restore marrow function after intensive therapy. To help distinguish between these two possible causes of relapse, we used safety-modified retroviruses, which contain the bacterial resistance gene NEO, to mark autologous marrow cells that had been collected from patients early in the phase of hematopoietic recovery after in vivo chemotherapy. The cells were then subjected to ex vivo CD34 selection following collection and 30% of the bone marrow were exposed to a safety-modified virus. This marrow was infused after delivery of systemic therapy, which consisted of total body irradiation (1,020 cGy), cyclophosphamide (120 mg/kg), and VP-16 (750 mg/m2). RT PCR assays specific for the bacterial NEO mRNA, which was coded for by the virus, and the bcr-abl mRNA showed that in two evaluable CML patients transplanted with marked cells, sufficient numbers of leukemia cells remained in the infused marrow to contribute to systemic relapse. In addition, both normal and leukemic cells positive for the retroviral transgenome persisted in the systemic circulation of the patients for at least 280 days posttransplant showing that the infused marrow was responsible for the return of hematopoiesis following the preparative therapy. This observation shows that it is possible to use a replication-incompetent safety-modified retrovirus in order to introduce DNA sequences into the hematopoietic cells of patients undergoing autologous bone marrow transplantation. Moreover, this data suggested that additional fractionation procedures will be necessary to reduce the probability of relapse after bone marrow transplantation in at least the advanced stages of the disease in CML patients undergoing autologous bone marrow transplantation procedures. 相似文献
85.
Cytogenetic and molecular analysis in Philadelphia negative CML 总被引:2,自引:0,他引:2
van der Plas DC; Hermans AB; Soekarman D; Smit EM; de Klein A; Smadja N; Alimena G; Goudsmit R; Grosveld G; Hagemeijer A 《Blood》1989,73(4):1038-1044
86.
Priming of human neutrophils with N-formyl-methionyl-leucyl- phenylalanine by a calcium-independent, pertussis toxin-insensitive pathway 总被引:1,自引:0,他引:1
Resting neutrophils may be "primed" to augmented effector function, eg, superoxide (O2-) production in the respiratory burst, upon a second stimulation with a variety of soluble agonists including formylated methionyl-leucyl-phenylalanine (FMLP) and phorbol myristate acetate (PMA). At priming concentrations of FMLP (5 x 10(-9) mol/L) that did not initiate O2- generation, two metabolic activities were noted: (1) approximately a threefold increase in the baseline intracellular calcium (Ca++i) level, that was not dependent on extracellular Ca++, and (2) a rapid rise in intracellular pH that was blocked by 5-(N,N- dimethyl) amiloride (DA), that had no effect on the Ca++i response to priming. Furthermore, there were no significant increases in inositol metabolites in cells primed and stimulated with FMLP compared with cells receiving the stimulating dose of FMLP alone and pretreatment with pertussis toxin (PT) (before the addition of the priming -5 x 10(- 9) mol/L dose of FMLP), whereas abolishing the response to FMLP during the second stage of stimulation, had (1) no effect on FMLP-primed cells subsequently stimulated with PMA, and (2) only partially ablated the rise in Ca++i initiated with FMLP. That FMLP priming involved distinctive processes to those of the well characterized FMLP-coupled Ca++-dependent activation cascade was shown by the full priming effect attained in a Ca++-free buffer, which did not sustain an O2- response to a second-stage FMLP stimulation, but sustained a primed response to PMA. These data demonstrate that FMLP primes human neutrophils by a Ca++-independent and PT-insensitive pathway, offering a functional model for studying heterogeneous FMLP receptor-coupled reactions. 相似文献
87.
KRZYSZTOF JONDERKO ADAM KOCA TOMASZ GOAB GERARD JONDERKO 《Journal of gastroenterology and hepatology》1989,4(6):505-511
The effect of increasing intravenous doses of synthetic salmon calcitonin (0.0044, 0.0088, 0.0175, and 0.0350 iu/kg per min) versus placebo on the fasted gall-bladder volume was assessed in seven normal subjects according to a double-blind study protocol. In addition, the action of calcitonin on meal-induced gall-bladder emptying was examined. Gall-bladder volumes were measured by means of real-time ultrasonography. Calcitonin evoked a dose-dependent relaxation of the fasted gall-bladder. A statistically significant increase of the fasted gall-bladder volume was observed with 0.0175 (23.4 +/- 5.5 cm3 placebo versus 33.9 +/- 7.7 cm3 calcitonin, P less than 0.001) and 0.0350 (21.4 +/- 4.6 cm3 placebo versus 36.1 +/- 8.4 cm3 calcitonin, P less than 0.01) iu/kg per min calcitonin, whereas a mean increase of the gall-bladder volume amounted to 32.1% and 46.5%, respectively. A significant delay of the gall-bladder emptying after calcitonin was reflected by a decrease of the ejection fraction: 23.2 +/- 8.3% calcitonin versus 57.8 +/- 6.9% placebo (P less than 0.02) at 20 min, and 40.5 +/- 8.8% calcitonin versus 67.2 +/- 3.8% placebo (P less than 0.02) at 30 min after the test meal. Calcitonin is concluded to have a potent relaxing effect on the human gall-bladder. 相似文献
88.
A new variant of type II von Willebrand disease with aberrant multimeric structure of plasma but not platelet von Willebrand factor (type IIF) 总被引:2,自引:0,他引:2
A patient with a lifelong bleeding disorder was diagnosed as having Type II von Willebrand disease. The larger multimers of von Willebrand factor were absent from her plasma but present in platelets. A high- resolution electrophoretic technique was used to study the complex structure of individual von Willebrand factor multimers. In normal plasma, each multimer could be resolved into five bands: a more intense central one and four less intense, two moving faster and two slower than the central band. In normal platelets, each multimer could also be resolved into five bands. The central one had a mobility similar to that in plasma, whereas the four satellite bands had a mobility that differed from that of the corresponding plasma bands. In the patient, platelet von Willebrand factor antigen content and ristocetin cofactor activity were normal, and von Willebrand factor showed the same structure of individual multimers as seen in normal platelets. On the other hand, plasma von Willebrand factor antigen and ristocetin cofactor activity were decreased, and the structure of individual von Willebrand factor multimers was different from that of normal plasma and similar to that seen in normal and patient's platelets. After infusion of 1-deamino-8-D-arginine vasopressin, the largest von Willebrand factor multimers, as well as new satellite bands with a mobility similar to those in normal plasma, appeared in the patient plasma, and the levels of von Willebrand factor antigen and ristocetin cofactor activity became normal. Yet no relevant change in the prolonged bleeding time was observed. This new variant of von Willebrand disease, therefore, is characterized by the presence of a dysfunctional von Willebrand factor molecule that exhibits unique structural abnormalities in plasma but appears to be normal in platelets. The designation of Type IIF is proposed for this type of von Willebrand disease in accordance with the terminology that has been previously used. 相似文献
89.
Morry Moskovitz MD Colin White MD Roy N. Barnett MD Sydney Stevens RN Edith Russell AB David Vargo MS Dr. Martin H. Floch MD 《Digestive diseases and sciences》1979,24(10):746-751
Increased concentrations of fecal bile acids and neutral sterols or their degradation products have been linked to certain diets and are implicated in colonic carcinogenesis. We measured fecal bile acid and neutral sterol concentrations by thin-layer and gas-liquid chromatography in 15 patients with colonic adenocarcinoma, 23 controls, and 16 patients with nongastrointestinal cancer. We compared these results with dietary intake. Detailed dietary histories showed no differences among the groups in the ingestion of calories, protein, fiber, fat, or carbohydrate. A wide variation in fecal concentration of individual bile acids and neutral sterols was found within each group, but no significant differences in the total bile acid or total neutral sterol per gram dry weight feces were found. Decreased coprostanol, coprostanone, and lithocholic acid excretion was found in the colon cancer group compared with controls. The fecal excretion of all bile acids and neutral sterols was lower significantly in the nongastrointestinal cancer patients with liver metastases as compared with those without. We conclude that total bile acid and total neutral sterol excretion is similar in the three groups, all ingesting similar diets. We cannot confirm reported increased excretion of total bile acids nor excessive bacterial conversion to degradation products in colonic cancer patients. Hepatic metastases correlate with decreased fecal excretion of both bile acids and neutral sterols, which may be due to diminished hepatobiliary excretion. 相似文献
90.
Autoantibody against erythrocyte protein 4.1 in a patient with autoimmune hemolytic anemia 总被引:1,自引:0,他引:1
Wakui H; Imai H; Kobayashi R; Itoh H; Notoya T; Yoshida K; Nakamoto Y; Miura AB 《Blood》1988,72(2):408-412
We observed the presence of a new autoantibody, anti-erythrocyte protein 4.1, in a patient with autoimmune hemolytic anemia (AIHA). Western blotting analysis revealed that IgG from the patient's plasma reacted with erythrocyte protein 4.1. However, among other patients with hemolytic diseases (six having AIHA and three each having either hereditary spherocytosis, elliptocytosis, or lead poisoning) as well as among control subjects, no antibody activity to protein 4.1 was observed. In addition to the anti-protein 4.1 antibody, two different kinds of anti-erythrocyte antibodies were detected by conventional serological studies in this patient. One of them was an anti-Ena-like antibody in the eluate from the patient's erythrocytes, while another was the anti-S-specific antibody in the plasma. An elution study and an absorption study using S antigen-positive erythrocytes demonstrated that the anti-protein 4.1 antibody differed from both the anti-Ena-like antibody and the anti-S antibody. Familial analysis of the patient revealed the same antibody in her brother, who did not have hemolytic anemia. These results demonstrate that anti-protein 4.1 antibody is considered to be included in the spectrum of anti-cytoskeleton autoantibodies, which have been observed in patients having increased cell lysis as well as in healthy subjects. 相似文献