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排序方式: 共有453条查询结果,搜索用时 0 毫秒
101.
BACKGROUND: Preoperative autologous blood donation is accepted as a standard of care for radical prostatectomy. Acute normovolemic hemodilution (ANH) is an alternative method for obtaining autologous blood. The cost and benefits of these two autologous blood-collection techniques are compared. STUDY DESIGN AND METHODS: Thirty consecutive patients scheduled for radical prostatectomy underwent ANH to a target hematocrit level of 28 percent. Blood was transfused in the perioperative period to maintain the hematocrit level > 25 percent. Hematocrit levels, transfusion outcomes and costs, and postoperative outcomes for these patients (hemodilution group) were compared with a matched patient cohort who preoperatively donated 3 units of blood for autologous use in prostatectomy surgery (nonhemodilution group, n = 30). RESULTS: Thirty patients underwent ANH to a hematocrit level of 28.7 +/− 1.7 percent, and 1740 +/− 346 mL (3.5 +/− 0.7 units) of blood were collected. Three (10%) of the patients in each cohort had allogeneic blood exposure. Transfusion costs were 73 percent higher for the nonhemodilution group patients than for the hemodilution group patients ($330 +/− $100 vs. $191 +/− $55, p < 0.001). No differences were found in postoperative outcomes. CONCLUSION: An integrated blood conservation program utilizing hemodilution and a defined transfusion trigger can decrease the requirement for preoperative donation of blood for autologous use in radical prostatectomy. Point-of-care autologous blood procurement is more cost-effective than preadmission donation of autologous blood units. 相似文献
102.
N Nurjhan F Kennedy A Consoli C Martin J Miles J Gerich 《Metabolism: clinical and experimental》1988,37(4):386-389
To assess whether plasma glycerol could be directly derived from plasma glucose, nine postabsorptive dogs were infused with [U-14C] glucose and [2-3H] glycerol to measure the rates of appearance of plasma glucose and glycerol and the conversion of plasma glucose to glycerol before (basal) and after two hours of infusion of glucose (45 mumol/kg/min). Basally (plasma glucose 4.9 +/- 0.2 mmol/L; plasma insulin 5.9 +/- 0.2 microU/mL), rates of appearance of plasma glucose and glycerol were 20 +/- 2 and 5.9 +/- 1.3 mumol/kg/min, respectively, and 1.6 +/- 0.6% of plasma glycerol was derived from plasma glucose. After glucose infusion (plasma glucose 9.1 +/- 0.7 mmol/L; plasma insulin 21.1 +/- 1.9 microU/mL), the rate of appearance of plasma glycerol decreased 80% to 1.1 +/- 0.3 mumol/kg/min and the percent of plasma glycerol from glucose increased significantly to 6.9 +/- 2.9. However, the absolute rate of conversion of glucose to glycerol did not change (0.09 +/- 0.03 v 0.07 +/- 0.03 mumol/kg/min). We conclude that even under conditions of stimulated glycolysis and inhibited lipolysis, only a small amount of plasma glycerol is derived from plasma glucose. Thus, rates of appearance of plasma glycerol can be used as a measure of rates of overall lipolysis in vivo. 相似文献
103.
The ability of glucagon to impair glucose tolerance has been questioned by studies involving infusion of exogenous glucagon during a glucose load. Since such hormone administration may not reflect the physiologic pattern of glucagon secretion and may result in hepatic downregulation to glucagon, the present experiments have examined the effects of intermittent andogenous hyperglucagonemia (induced by episodic infusion of arginine) on plasma glucose profiles of normal man following ingestion of mixed meals. In control studies following meal ingestion, plasma glucose, insulin and glucagon increased respectively 15–30 mg/dl, 30–60 uU/ml and 25–50 pg/ml. When meals were accompanied by arginine infusions, plasma glucagon responses were augmented three to fourfold (p < 0.05). Amplitudes of glycemic excursions during infusion of arginine (345 ± 40 mg/dl) were significantly augmented compared to those observed in control studies (286 ± 34 mg/dl, p < 0.02). These results indicate that intermittent increases in plasma glucagon within the physiologic range can adversely affect postprandial glucose profiles in normal man despite concomitant hyperinsulinemia and suggest that such hyperglucagonemia may contribute to impaired postprandial glucose tolerance in diabetic individuals in whom insulin secretion is deficient. 相似文献
104.
Mechanisms of leukemic cell clonal dominance may include aberrations of transmembrane signaling. In particular, neoplastic transformation has been associated with reduced capacity for hormone-stimulated adenylate cyclase activity. In the present study, prostaglandin E, a hormonal activator of adenylate cyclase that has antiproliferative activity in myeloid cells, and cholera toxin, an adenylate cyclase agonist that functions at a postreceptor site by activating the adenylate cyclase stimulatory GTP-binding protein (Gs), were studied for antiproliferative activity in two murine myeloid cell lines. FDC-P1, an interleukin 3 (IL 3)-dependent myeloid cell line and a tumorigenic IL 3- independent subline, FI, were resistant to these antiproliferative agents. The in vitro ability of the "differentiation" agent, sodium butyrate, to reverse their resistance to adenylate cyclase agonists was studied. The antiproliferative action of butyrate involved augmentation of transmembrane adenylate cyclase activity. Increased adenylate cyclase catalyst activity was the primary alteration of this transmembrane signaling group leading to the functional inhibitory effects on leukemia cells, although alterations in regulatory G- proteins appear to play a secondary role. 相似文献
105.
To characterize the adrenergic effects of epinephrine on somatostatin, insulin and glucagon release and to assess the potential interactions of islet A, B, and D cell function, isolated rat islets were incubated in vitro with epinephrine (0.05–20 μM) in the presence and absence of the alpha adrenergic antagonist, phentolamine (2 or 4 μM), and/or the beta adrenergic antagonist, propranolol (2 μM). At concentrations of epinephrine at or less than 1 μM, somatostatin and insulin release were inhibited while glucagon release was unaffected. At greater epinephrine concentrations, somatostatin and glucagon release were increased while insulin release was further suppressed. The threshold as well as the half-maximal effect of epinephrine occurred at lower concentrations for somatostatin release than for insulin and glucagon release. The inhibitory effect of 0.5 μM epinephrine on somatostatin and insulin release was completely reversed by phentolamine and was unaffected by propranolol. The stimulatory effect of 2 and 20 μM epinephrine on somatostatin and glucagon release was not observed when propranolol was included in the incubation medium along with epinephrine. These results demonstrate that rat islet A, B, and D cells differ in their sensitivity to alpha and beta adrenergic effects. At low concentrations of epinephrine, alpha adrenergic effects on D cells predominate over beta adrenergic effects whereas at greater concentrations of epinephrine alpha and beta effects appear to be equal; alpha adrenergic effects of epinephrine predominate over those of beta on the B cell at least up to 20 μM epinephrine; exclusively beta adrenergic effects of epinephrine are observed on the A cell at least up to 20 μM epinephrine. 相似文献
106.
Riboldi P; Gaidano G; Schettino EW; Steger TG; Knowles DM; Dalla-Favera R; Casali P 《Blood》1994,83(10):2952-2961
We analyzed the reactivity and the structure of the VH and VL segments of two IgM monoclonal antibodies (MoAbs) produced by spontaneously in vitro outgrowing cell lines, HBL-2 and HBL-3, established from two acquired immunodeficiency syndrome (AIDS) patients with Epstein-Barr virus (EBV)-negative Burkitt's lymphoma (BL). These B-cell clones were representative of the respective neoplastic parental clones, as determined by immunophenotypic and molecular genetic analysis. The IgM MoAbs were highly specific for the i determinant on red blood cells (cold agglutinins), but bound none of the other eight self and nine foreign antigens (Ags) tested, including those most commonly recognized by natural antibodies or autoantibodies. Structural analysis showed that the IgM MoAb VH segment sequences were 93.5% and 84.2% identical with that of the germline VH4-21 gene, which encodes the vast majority of cold agglutinins that are specific for the i/l carbohydrate Ag and are produced under chronic lymphoproliferative conditions. The HBL-2 MoAb VH4-21 gene segment was juxtaposed with 20P3 and JH6 genes and paired with a V lambda 1 segment, the sequence of which was 95.5% identical to that of the germline Humlv117 gene; the HBL-3 MoAb VH4-21 gene segment was juxtaposed with DXP'1 and JH5 genes and paired with a V lambda 1 segment, the sequence of which was 86.7% identical to that of the germline Humlv1L1 gene. The high degree of conservation of the VH4-21 gene in the human population, the nature of the nucleotide differences in the expressed VH4-21 segments, and the presence of nucleotide substitutions in the HBL-2 and HBL-3 IgM MoAb JH and/or J lambda segments suggested that the MoAb V segments underwent a process of somatic hypermutation. This was formally shown in the HBL-3 MoAb VH segment, by differentially targeted polymerase chain reaction amplification of the HBL-3 MoAb-producing cell genomic DNA. In addition, cloning and sequencing of the genomic DNA from fibroblasts of the same patient whose neoplastic B cells gave rise to the HBL-3 cell line yielded a germline copy of the VH4-21 gene. Thus, the expression of VH4-21 gene products may be involved in a self Ag-driven process of clonal B-cell expansion and selection associated with BL in these AIDS patients. 相似文献
107.
Apoptosis is the major form of cell death associated with the action of chemotherapeutic agents on tumor cells, and therefore the expression of genes that interfere with apoptosis can have important consequences for the efficacy of therapeutic approaches. Here we show that K562, a chronic myelogenous leukemia (CML) cell line expressing the BCR-ABL fusion protein, are resistant to the induction of apoptosis by a number of agents and conditions. Antisense oligodeoxynucleotides corresponding to the translation start of bcr downregulate bcr-abl protein in these cells and render them susceptible to induction of apoptosis by chemotherapeutic agents or serum deprivation. Expression of a temperature sensitive v-Abl protein reverses the effects of the antisense oligonucleotides, such that the cells remain resistant to apoptosis at the permissive temperature. These data indicate that bcr- abl acts as an anti-apoptosis gene in CML cells and suggests that the effect is dependent on the abl kinase activity in this chimeric protein. Inhibition of bcr-abl to render CML cells susceptible to apoptosis can be combined with therapeutic drugs and/or treatment capable of inducing apoptosis to provide an effective strategy for elimination of these cells. 相似文献
108.
OBJECTIVE: This study aims to compare levels of psychological distress and the quality of life in the hard of hearing with levels reported by the signing deaf, and the hearing population. METHOD: A total of 373 members of the Hard of Hearing Association completed the brief WHO's Quality of Life, 12-item General Health Questionnaire and Brief Symptom Inventory, and provided details about their initial and current deafness. RESULTS: The hard of hearing have worse social relationships than the signing deaf, and are disadvantaged relative to the hearing in all areas measured. Quality of life is related to the level of satisfaction with the hearing achieved by hearing aids. CONCLUSION: General psychiatrists need to be aware that patients who are hard of hearing may be even more isolated than deaf people in a signing community. Hard of hearing patients with unsatisfactory hearing aids can be greatly assisted by cochlear implants. 相似文献
109.
Nieuwmeyer FJ Damen M Gerich A Rusmini F van der Voort Maarschalk K Vromans H 《Pharmaceutical research》2007,24(10):1854-1861
Purpose Water content and granule size are recognized as critical process and product quality parameters during drying. The purpose
of this study was to enlighten the granule behavior during fluid bed drying by monitoring the major events i.e. changes in
water content and granule size.
Methods NIR spectra collected during drying and water content of sampled granules were correlated by principal component analysis
(PCA) and partial least squares regression (PLSR). NIR spectra of dried granules were correlated to median granule size in
a second PCA and PLSR.
Results The NIR water model discriminates between various stages in fluid-bed drying. The water content can be continuously predicted
with errors comparable to the reference method. The four PLS factors of the granule size model are related to primary particle
size of lactose, median granule size exceeding primary particle size and amorphous content of granules. The small prediction
errors enable size discrimination between fines and granules.
Conclusion For product quality reasons, discrimination between drying stages and end-point monitoring is highly important. Together with
the possibilities to determine median granule size and to distinguish fines this approach provides a tool to design an optimal
drying process. 相似文献
110.