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991.
Seven patients with refractory lymphomas underwent marrow reconstitution with peripheral blood stem cells (PBSCs) harvested by large-volume leukapheresis (LVL). PBSCs were collected from all patients more than 1 month after the last cycle of chemotherapy, and no patient received growth factors. The median number of LVL procedures performed per patient was 4.5, with a mean volume of 24.5 L of blood processed per procedure to obtain 7 x 10(8) mononuclear cells per kg. Autologous PBSCs and platelets were frozen at a controlled rate in plasma and 10-percent dimethyl sulfoxide and stored in the vapor phase of liquid nitrogen. This group of patients was compared to a control group (n = 18) who received medullary marrow (MM) transplants for the same diagnoses under the same protocols during the same period. Posttransplant days to white cell engraftment (PBSC = 17, MM = 15.5) were no different. Days to platelet independence were significantly longer in the LVL PBSC group (PBSC = 33, MM = 16; p < 0.05). This pattern of engraftment is typical of patients treated in this manner. Although Day 0 platelet counts (PBSC = 75.5 x 10(9)/L, MM = 85 x 10(9)/L) and total single-donor unit platelet use (PBSC = 8, MM = 9) were no different, Day 1 platelet counts (PBSC = 128 x 10(9)/L, MM = 61.5 x 10(9)/L; p < 0.05) and Day 14 platelet use (PBSC = 5, MM = 8; p < 0.05) were significantly different, because of the transfusion of cryopreserved autologous platelets with PBSCs on Day 0.  相似文献   
992.
993.
This article provides an update on the global cancer burden using the GLOBOCAN 2020 estimates of cancer incidence and mortality produced by the International Agency for Research on Cancer. Worldwide, an estimated 19.3 million new cancer cases (18.1 million excluding nonmelanoma skin cancer) and almost 10.0 million cancer deaths (9.9 million excluding nonmelanoma skin cancer) occurred in 2020. Female breast cancer has surpassed lung cancer as the most commonly diagnosed cancer, with an estimated 2.3 million new cases (11.7%), followed by lung (11.4%), colorectal (10.0 %), prostate (7.3%), and stomach (5.6%) cancers. Lung cancer remained the leading cause of cancer death, with an estimated 1.8 million deaths (18%), followed by colorectal (9.4%), liver (8.3%), stomach (7.7%), and female breast (6.9%) cancers. Overall incidence was from 2-fold to 3-fold higher in transitioned versus transitioning countries for both sexes, whereas mortality varied <2-fold for men and little for women. Death rates for female breast and cervical cancers, however, were considerably higher in transitioning versus transitioned countries (15.0 vs 12.8 per 100,000 and 12.4 vs 5.2 per 100,000, respectively). The global cancer burden is expected to be 28.4 million cases in 2040, a 47% rise from 2020, with a larger increase in transitioning (64% to 95%) versus transitioned (32% to 56%) countries due to demographic changes, although this may be further exacerbated by increasing risk factors associated with globalization and a growing economy. Efforts to build a sustainable infrastructure for the dissemination of cancer prevention measures and provision of cancer care in transitioning countries is critical for global cancer control.  相似文献   
994.
995.
BACKGROUND: After the collection of granulocyte-colony-stimulating factor (G-CSF)-mobilized peripheral blood stem cells from healthy donors, the donor platelet counts fall. However, the magnitude and duration of this decrease are not known. STUDY DESIGN AND METHODS: Sixty healthy people were given G-CSF (5, 7.5, or 10 micrograms/kg/day) for 5 days (Days 1–5), and 1 peripheral blood stem cell component was collected on Day 6. The platelet count, white cell count, absolute neutrophil count, hematocrit, and red cell count were measured before administration of G-CSF (Day 0), before collection of peripheral blood stem cells on Day 6, and on Days 8, 10, 13, 16, and 20. RESULTS: The platelet count fell from 261 +/? 47 × 10(9) cells per L on Day 0 to 159 +/? 30 × 10(9) cells per L on Day 8 (p < 0.0001) and reached its lowest level on Day 10 (146 +/? 30 × 10(9)/L; p < 0.001). Compared to Day 0 levels, the platelet count was lower on Day 13 (185 +/? 49 × 10(9)/L, p < 0.001), was the same on Day 16 (270 +/? 53 × 10(9)/L), and was greater on Day 20 (333 +/? 60 × 10(9)/L, p < 0.0001). The white cell count returned to pretreatment values on Day 13, and the absolute neutrophil count returned to pretreatment values on Day 10 (Day 0 white cell count = 6.05 +/? 1.59 × 10(9)/L and Day 0 absolute neutrophil count = 3.97 +/? 1.52 × 10(9)/L). On Day 20, both were less than pretreatment values (white cell count = 5.14 +/? 1.24 × 10(9)/L, p = 0.0007 and absolute neutrophil count = 3.20 +/? 1.24 × 10(9)/L, p = 0.0036). The red cell counts on Day 16 (4.52 +/? 0.41 × 10(12)/L) and Day 20 (4.42 +/? 0.39 × 10(12)/L) were less than Day 0 values (4.73 +/? 0.43 × 10(12)/L, p = 0.008 and p < 0.0001, respectively). The hematocrit on Day 20 (39.2 +/? 3.2%) was also less than that on Day 0 (41.2 +/? 4.8%; p = 0.01). The changes in these blood counts were not affected by the dose of the G-CSF. CONCLUSION: After stimulation with granulocyte-colony-stimulating factor and the collection or peripheral blood stem cells, the platelet counts in normal donors were decreased for at least 7 days (Days 6–13). Two weeks after collection of peripheral blood stem cells (Day 20), platelet production was increased, but the production of neutrophils and red cells was decreased. If two or more peripheral blood stem cell components are collected, then the platelet count should be measured after the second and subsequent collections. Further studies on the long-term effect of G-CSF on blood counts are needed.  相似文献   
996.
In genetic disorders caused by point mutations or small frameshift mutations, affected members of the same family are expected to have the same mutation in the causative gene. We have recently evaluated a family in which this was not the case. Maternal cousins with Wiskott-Aldrich syndrome (WAS; MIM 301000) had two different but contiguous single base pair deletions in WAS. The proband had an A deletion in codon 242 in exon 7 of WAS; his two cousins had a C deletion in codon 241. The mother of the proband was heterozygous for the A deletion allele, but her three sisters, including the mother of the affected cousins, were heterozygous for the C deletion. Both deletions occurred on the haplotype from the unaffected maternal great-grandfather. The maternal grandmother, who was a carrier of WAS, based on a non-random pattern of X chromosome inactivation in T cells, was mosaic for both deletions. These findings are most consistent with the mutations originating in a male gamete with different mutations on the two strands of DNA, a bichromatid mutation.  相似文献   
997.
The effects of a fat meal upon plasma insulin, glucagon, and glucagon-like immunoreactivity (GLI) have been studied in conscious dogs and in human volunteers. In dogs the intraduodenal instillation of 10 g/kg of peanut oil was accompanied by increases in the mean plasma levels of all three polypeptides that averaged 5 muU/ml, 107 pg/ml, and 2.1 ng/ml, respectively. 3 g/kg of peanut oil, when emulsified with egg yolk, elicited a much greater response of the three hormones, and a physiologic dose of 1 g/kg in emulsified form also caused a significant rise in glucagon and GLI. The islet cell hormone response was not ascribable to chylomicronemia since intravenous infusion of canine chyle failed to stimulate glucagon secretion; moreover, in dogs with a thoracic duct fistula in which chyle was excluded from the circulation, the intraduodenal administration of a fat meal elicited the normal islet cell hormone response, as well as a rise in GLI. 10 g/kg of medium-chain triglycerides failed to elicit these same responses. In six human volunteers the oral administration of 3 g/kg peanut oil was accompanied by increments of 2 muU/ml, 26 pg/ml, and 1.5 ng/ml in the mean levels of insulin, glucagon, and GLI. The changes in insulin and glucagon in man were neither statistically significant nor biologically impressive.It is concluded that in dogs fat absorption is accompanied by prompt and substantial increases in plasma glucagon and GLI and a small transient rise in insulin. The evidence favors an enterogenic signal to the islets of Langerhans rather than their stimulation by chylomicrons. Pancreozymin is qualified to serve as such a signal. The physiologic implications of this study are considered.  相似文献   
998.
BACKGROUND: One in every 1000 units of platelets is bacterially contaminated, which puts patients at risk for transfusion-associated sepsis and death. However, there is currently no screening test in place to detect contaminated units. The use of commercially available multiple-reagent urine dipsticks for this purpose was evaluated. STUDY DESIGN AND METHODS: Platelet concentrates were inoculated with either sterile saline or suspensions of Staphylococcus aureus, Staphylococcus epidermidis, Bacillus cereus, Klebsiella pneumoniae, or Serratia marcescens to a final concentration of 50 colony-forming units (CFU) per mL. The platelets were analyzed daily by the use of multiple- reagent strips, quantitative culture, and glucometry. RESULTS: B cereus grew rapidly, reaching 10(7) CFU per mL 1 day after inoculation, while S. epidermidis grew slowly, achieving similar concentration 4 to 6 days after inoculation. Two of 10 dipstick reagents, glucose and pH, proved useful in detecting bacteria. Both were lower in bacterially contaminated units than in controls. Glucose data obtained from automated analyzers validated the dipstick data. All organisms were detected at concentrations > or = 10(7) CFU per mL, and S. aureus and K. pneumoniae were detected in the range of 10(3) to 10(5) CFU per mL. CONCLUSION: The multiple-reagent test used had a sensitivity and specificity of 95 percent (> or = 10(7) CFU/mL) and 98 to 100 percent, respectively. These data indicate that urine dipsticks can be used to rapidly and inexpensively detect bacterial contamination in platelet concentrates, which potentially will reduce morbidity and mortality at minimal cost.  相似文献   
999.
1000.
BACKGROUND: Several studies suggest that perioperative blood transfusion is a major independent risk factor for postoperative bacterial infections. Transfusion-induced immunosuppression is thought to mediate this effect. STUDY DESIGN AND METHODS: In a randomized clinical trial comprising 697 patients with colorectal cancer, the relationship between two types of red cell components (buffy coat- depleted packed red cells and white cell-reduced [filtered] packed red cells) and postoperative bacterial infections was analyzed. RESULTS: Both types of red cells appeared to be associated with a greater incidence of postoperative infection than was no transfusion (39 vs. 24%, p < 0.01). A dose-response relationship could be demonstrated: the corrected relative risk was 1.6 for 1 to 3 units of red cells and 3.6 for more than 3 units. Multivariate analyses identified the transfusion of red cells and tumor location as the only significant independent risk factors for postoperative bacterial infection. CONCLUSION: Because allogeneic white cells, plasma, microaggregates, citrate, and platelets could be ruled out as risk factors for transfusion-associated postoperative infections, it is hypothesized that the transfusion of red cells is a potentially detrimental factor that transiently impairs the clearance of bacteria by phagocytic cells.  相似文献   
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