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991.
992.
The aggressive clinical course and the distinctive histologic, cytochemical, and cytogenetic features of an adult non-Sezary T-cell lymphoma with suppressor activity have been investigated. Morphological and ultrastructural analysis of neoplastic cells from peripheral blood and involved lymph nodes revealed cells with convoluted nuclei, prominent cytoplasmic azurophilic granules, well developed Golgi apparatus, short strands of endoplasmic reticulum, and moderate numbers of ribosomes and mitochondria. Cytochemical reactions showed acid phosphatase (ACP) positivity in virtually all of the neoplastic cells; and a substantial percentage of the cells, the tartrate-resistant acid phosphatase (T-ACP) isoenzyme was observed. Granular naphthyl acetate esterase (A-EST) reactivity was not present. The histological and cytochemical features of these neoplastic suppressor cells were compared with those recently described for the suppressor T-cell fraction isolated from normal peripheral blood T-cell by Fc gamma- rosette formation. The aneuploid clone had 47 chromosomes with multiple complex abnormalities, including a 14q + chromosome formed by the tandem translocation of two no. 14 chromosomes and translocations involving the long arms of no. 2 and no. 9 at band 9q34. These latter changes are particularly common in T-cell disorders. The extensive analysis of this histologic, cytochemical, and cytogenetic features of this adult T-cell suppressor lymphoma should help to clarify the criteria for distinguishing among the subsets of T-cell neoplasms with definable immunologic function.  相似文献   
993.
Miale  JB; Kent  JW 《Blood》1975,45(1):97-106
Data are presented to support the concept that the vitamin K-dependent coagulation factors are adsorbed onto the platelet membrane and that these make up part of the "plasma atmosphere" necessary for the aggregation of platelets by various agents. Together with evidence that other coagulation factors also are part of the plasma atmosphere, it is suggested that the aggregation reaction is part of the coagulation sequence. The immunologic approach to demonstrating constituents of the platelet membrane promises to be a highly specific technique for studying further the constituents of the platelet membrane and their reactions in hemostasis.  相似文献   
994.
The relative requirements of colonies derived from erythroid (BFU-E) and myeloid (CFU-c) progenitors for transferrin were examined using monoclonal antibodies directed against the transferrin molecule (TF-6) or its cell surface receptor (TFR-A12, TFR1-2B). Growth of erythroid bursts was profoundly reduced at concentrations of all three antibodies that had no effect on CFU-c-derived colonies. When TFR1-2B was layered over cultures established one to seven days previously, further burst development was inhibited, and degeneration of early erythroid colonies was observed. Addition of erythropoietin augmented transferrin receptor expression on cells harvested after 1 to 2 weeks in culture and analyzed by flow cytometry. Recombinant human erythropoietin gave results comparable to those obtained in experiments using human urinary erythropoietin. Analysis of erythroblasts plucked directly from culture plates confirmed the presence of transferrin receptors on BFU-E-derived colonies. Thymidine incorporation was maximal early in the second week of culture and coincided with high transferrin receptor expression. These data demonstrate that transferrin must be available into the second week of culture to support the growth and differentiation of BFU- E-derived erythroid bursts, that the generation of erythroid colonies from BFU-E is more dependent on transferrin than myeloid colony formation from CFU-c, and that erythropoietin modulates the expression of transferrin receptors on growing bursts.  相似文献   
995.
996.
With the goal of optimizing patient care, standards for training in cardiac computed tomography have been developed collaboratively by the Canadian Association of Radiologists and the Canadian Cardiovascular Society. These standards apply to both radiologists and cardiologists.  相似文献   
997.
Inhibitors of COX indicate that upregulation of inflammatory eicosanoids produced by COX, and in particular prostaglandin E(2) (PGE(2)), are early events in the development of colorectal cancer (CRC). Ginger has shown downregulation of COX in vitro and decreased incidence/multiplicity of adenomas in rats. This study was conducted to determine if 2.0 g/d of ginger could decrease the levels of PGE(2), 13-hydroxy-octadecadienoic acids, and 5-, 12-, and 15-hydroxyeicosatetraenoic acid (5-, 12-, and 15-HETE), in the colon mucosa of healthy volunteers. To investigate this aim, we randomized 30 subjects to 2.0 g/d ginger or placebo for 28 days. Flexible sigmoidoscopy at baseline and day 28 was used to obtain colon biopsies. A liquid chromatography mass spectrometry method was used to determine eicosanoid levels in the biopsies, and levels were expressed per protein or per free arachidonic acid. There were no significant differences in mean percent change between baseline and day 28 for any of the eicosanoids, when normalized to protein. There was a significant decrease in mean percent change in PGE(2) (P = 0.05) and 5-HETE (P = 0.04), and a trend toward significant decreases in 12-HETE (P = 0.09) and 15-HETE (P = 0.06) normalized to free arachidonic acid. There was no difference between the groups in terms of total adverse events P = 0.55). On the basis of these results, it seems that ginger has the potential to decrease eicosanoid levels, perhaps by inhibiting their synthesis from arachidonic acid. Ginger also seemed to be tolerable and safe. Further investigation in people at high risk for CRC seems warranted.  相似文献   
998.
999.

Objective

Our objective was to evaluate the impact of routine use of double-J stents on the incidence of urinary tract infection after renal transplantation.

Methods

We conducted a retrospective-comparative single-centre study in 310 consecutive adult deceased donor kidney recipients transplanted from 2002 to 2006. Patients were divided in two groups, with or without urinary stent implantation. To evaluate the predictive factors for UTI, donor and recipients pre- and post-transplantation data were analysed. Early urological complications and renal function within 12 months of transplantation were included as well.

Results

A total of 157 patients were enrolled to a stent (ST) and 153 patients to a no-stent (NST) group. The rate of urinary tract infection at three months was similar between the two groups (43.3% ST vs. 40.1% NST, p = 0.65). Of the identified pathogens Enterococcus and Escherichia coli were the most common species. In multivariate analysis neither age nor immunosuppressive agents, BMI or diabetes seemed to have influence on the rate of UTI. When compared to males, females had a significantly higher risk for UTI (54.0% vs. 33.5%).

Conclusion

Prophylactic stenting of the ureterovesical anastomosis does not increase the risk of urinary tract infection in the early postoperative period.  相似文献   
1000.
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