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排序方式: 共有381条查询结果,搜索用时 93 毫秒
61.
62.
Emergency room radiography of asthma: an efficacy study 总被引:2,自引:0,他引:2
63.
Bishop MR; Anderson JR; Jackson JD; Bierman PJ; Reed EC; Vose JM; Armitage JO; Warkentin PI; Kessinger A 《Blood》1994,83(2):610-616
Between June 1989 and June 1992, 144 patients participated in sequential clinical trials using peripheral blood progenitor cells (PBC) as their sole source of hematopoietic rescue following high-dose chemotherapy. All patients had received prior extensive combination chemotherapy and had marrow defects that precluded autologous bone marrow transplantation (ABMT). PBC were collected according to a single apheresis protocol. The initial 86 patients (group 1) had PBC collected without mobilization. Beginning in April 1991, PBC were mobilized solely with recombinant human granulocyte-macrophage colony-stimulating factor (rHuGM-CSF). Thirty-four patients (group 2) received rHuGM-CSF at a dose of 125 micrograms/m2/d by continuous intravenous infusion, and 24 patients (group 3) received rHuGM-CSF at a dose of 250 micrograms/m2/d by continuous intravenous infusion. Patients underwent at least six aphereses and had a minimum of 6.5 x 10(8) mononuclear cells (MNC)/kg collected. Cytokines were not routinely administered immediately after transplantation. A median of nine aphereses were required to collect PBC in group 1 and seven aphereses for groups 2 and 3 (P = .03). The time required to recover 0.5 x 10(9)/L granulocytes after transplant was significantly shorter (P = .0004) for the mobilized groups; the median time to recovery was 26 days for group 1, 23 days for group 2, and 18 days for group 3. Transplantation of PBC mobilized with rHuGM-CSF resulted in a shorter time to platelet (P = .04) and red blood cell (P = .01) transfusion independence. Mobilization with rHuGM-CSF alone resulted in efficient collection of PBC, that provided rapid and sustained restoration of hematopoietic function following high-dose chemotherapy. Mobilization of PBC with rHuGM-CSF alone is an effective method for patients who have received prior chemotherapy and have bone marrow abnormalities. 相似文献
64.
Median survival is as little as 6 months for patients with refractory anemia with excess blasts who demonstrate an abnormal karyotype in the majority of marrow cells. We treated a patient who presented with 29% marrow blasts and 90% abnormal metaphases with 13-cis-retinoic acid. He achieved a complete clinical and cytogenetic remission during therapy. To determine the mechanism of the response, serial studies were done of the effects of 13-cis-retinoic acid and dexamethasone on in vitro growth of his marrow cells. During clinical remission, when the drug was not administered, marrow growth remained significantly depressed. During relapse, the remission growth pattern was replaced by overgrowth of the karyotypically abnormal monocytoid clone. Clonal growth occurred in cultures containing colony-stimulating activity or dexamethasone but was absent in cultures containing concentrations of 13-cis-retinoic acid achieved in vivo. After the drug was reinstituted, a second clinical stabilization developed. Since 13-cis-retinoic acid inhibits normal monocyte colony growth, we postulate that the patient's unusual clinical responses to the drug were due to in vivo growth inhibition of the malignant monocytoid clone. 相似文献
65.
Perioperative blood transfusion and cancer recurrence: meta-analysis for explanation 总被引:9,自引:0,他引:9
EC Vamvakas 《Transfusion》1995,35(9):760-768
BACKGROUND: Meta-analysis was used to explain disagreements across observational studies in regard to the association between perioperative transfusion and cancer recurrence. STUDY DESIGN AND METHODS: Observational studies published in English from 1982 through 1994 were retrieved. Five or more articles published in complete form were identified for each of six cancer sites: colorectum, breast, head and neck, lung, prostate, and stomach. Necessary information for building a 2 × 2 contingency table could be extracted from 60 studies. Summary relative risks (RR) reflecting the "average" adverse transfusion effect were computed for each cancer site by the random- effects method. Seven study characteristics were examined as potential explanations for the disagreements among the published studies. RESULTS: Before any adjustment for the effect of confounding, computed crude summary RRs suggested a significant (p < 0.05) deleterious transfusion effect in all cancer sites, except for breast. The RR of an adverse outcome was 1.49 in colorectal cancer (95% CI, 1.23-1.79) and ranged from 1.06 in breast cancers to 3.62 in head and neck cancers. The disagreements among published studies were most marked in the case of colorectal and gastric cancers. These discrepancies could be explained, in part, by study design, because prospective investigations had not produced a significant unadjusted transfusion effect (RR = 1.18; 95% CI, 0.93-1.51 in the case of colorectal cancer). CONCLUSION: A reduction in the size of the computed unadjusted transfusion effect (of an appropriate magnitude to adjust for the effect of confounding) might eliminate the significance of the average adverse effect in most studied cancer sites. Whether the entire unadjusted transfusion effect should be ascribed to the effect of confounding or whether a true, deleterious transfusion effect also exists can be resolved only by randomized controlled trials. 相似文献
66.
鉴定γB-晶体蛋白非酶糖基化位点。方法用离子交换HPLC纯化小牛晶状体γB-晶体蛋白,与果糖保温后用糜蛋白酶水解。糖基化的肽用Affi-Gel601柱层析纯化,并用RP-HPLC分离各肽。 相似文献
67.
Bondanelli M; Ambrosio MR; Franceschetti P; Guerrini R; Valentini A; degli Uberti EC 《Human reproduction (Oxford, England)》1998,13(5):1159-1162
There is evidence that endogenous opioid peptides exert an inhibitory
effect on pituitary luteinizing hormone (LH) secretion both in animals and
in humans, by interacting with mu-opioid receptors. However, a role for
delta-opioid receptors in the regulation of gonadotrophin releasing hormone
(GnRH) secretion has recently been suggested. In the present study, we
evaluated the effect of the highly selective delta-opioid receptor agonist
deltorphin on the LH and follicle stimulating hormone (FSH) responses to
naloxone in six healthy fertile women during the luteal phase of the
menstrual cycle. Deltorphin infusion alone (7 microg/kg/min for 60 min) did
not significantly change the basal serum concentrations of LH in this group
of women. The intravenous (i.v.) bolus administration of naloxone (15 mg)
induced a significant (P < 0.001) increase in serum LH concentrations
(from a mean basal value of 4.24+/-1.10 IU/l to a peak of 13.27+/-1.8
IU/l). The LH response to naloxone was significantly (P < 0.001) blunted
by preinfusion of deltorphin (13.27+/- 1.80 IU/l versus 4.80+/-1.18 IU/l).
No significant changes in FSH concentrations were observed during
deltorphin, naloxone or deltorphin plus naloxone administration. These data
indicate that activation of delta-opioid receptors can reduce
naloxone-induced LH release, suggesting a possible role of delta receptors
in opioidergic modulation of LH secretion in women.
相似文献
68.
Low-oxygen-affinity red cells produced in a large-volume, continuous- flow electroporation system 总被引:1,自引:0,他引:1
BACKGROUND: Human red cells containing inositol hexaphosphate (IHP) have a lowered O2 affinity, though they are able to bind and carry about the same amount of oxygen as native cells. These modified cells therefore deliver oxygen more efficiently to the tissues, which is a property of potential clinical utility. Investigators set out to devise a system and procedure by which large volumes of IHP-containing red cells, suitable for transfusion, could be produced quickly and efficiently. STUDY DESIGN AND METHODS: The encapsulation of IHP into human red cells by use of several variations of static electroporation was performed to define the conditions necessary for optimal IHP incorporation and cell survival. These conditions were used as a starting point for optimization of a flow electroporation system. RESULTS: When fresh human red cells in a 35 mM IHP solution are subjected to three exponential pulses of field strength of 2.98 +/− 0.064 kV per cm per pulse and pulse length of 2.0 +/− 0.2 msec per pulse while flowing through a cooled electroporation chamber, the condition of the resultant cells, according to the criteria used here, is optimized. After storage for 24 hours in plasma at 37 degrees C, the cells show more than 85-percent survival (in vitro) and hematologic indices nearly identical to those of unpulsed control cells. The p50 value of these cells, however, has doubled to 50.4 +/− 2.0 torr. The processing time for 1 unit of blood is 90 minutes. CONCLUSION: These data indicate that the system described here can efficiently produce low-oxygen-affinity red cells in volumes that are useful in clinical applications. 相似文献
69.
J Farquharson EC Jamieson RW Logan MB McFadyen WJ Patrick AG Howatson F Cockburn 《Archives of disease in childhood》1998,79(1):28-32
Abnormal fetal and infant growth have increasingly been correlated with adult onset cardiovascular disease. To date, there is little known about the lipid fatty acid profiles in infant cardiovascular tissue. Therefore, we analysed total lipid fatty acids from thoracic and abdominal aorta intima and media from 24 normally grown sudden infant death syndrome cases. Aorta from small for gestational age (n = 2), failure to thrive from birth (n = 3), and premature (n = 1) infants were also examined. Dihomo-gamma-linolenic acid (C20:3n-6) and oleic acid (C18:1n-9) concentrations were significantly lower in the thoracic than in the abdominal aorta. Similar dietary related differences were found in the subgroup (n = 15) of infants fed on formula milks. Both abdominal and thoracic intimal arachidonic (C20:4n-6) to dihomo-gamma-linolenic acid ratios were greater in the infants with retarded growth after birth than in their normally grown counterparts. Growth restriction in infancy might disrupt the normal accretion of vascular endothelial polyunsaturated fatty acids. 相似文献
70.
Cordeiro R Lima Filho EC Salgado PE 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》1996,12(4):455-463
We randomly selected twenty lead workers from an electric accumulator factory in the State of S?o Paulo, Brazil, whose blood lead level and urinary d-aminolevulinic acid level were below 60 mg/dL and 10 mg/L, respectively. The workers were submitted to a standard motor nerve conduction velocity study of the right radial nerves, in addition to blood lead dosage. Based on these measures, a first-order linear regression model was adjusted, where the dependent variable was conduction velocity and the independent variable was the blood lead level. Analyzing the fitted model, we inferred that the negative predictive value of the Brazilian biological exposure limit is 0.63. In order for the above biological exposure limit to have a negative predictive value of 0.99, the study suggests that it be reduced from its present value (60 mg/dL) to 32 mg/dL. 相似文献