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61.
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
62.
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
63.
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
64.
R Booy SA Hodgson MP Slack EC Anderson RT Mayon-White ER Moxon 《Archives of disease in childhood》1993,69(2):225-228
For a seven year period (1985-91) clinical and epidemiological data were prospectively collected on children aged < 10 years with microbiologically confirmed invasive Haemophilus influenzae type b infection in the Oxford region to study the epidemiology of the disease and determine the potential impact of early primary immunisation in infants. Computer records of primary immunisations given to these cases were retrospectively analysed and, where necessary, hospital and general practitioner records were searched to determine the immunisation history. Over the seven year period, 416 cases of invasive H influenzae type b disease were reported. Widescale immunisation against H influenzae type b began in 1991 as part of a regional trial. The estimated annual incidence for invasive disease between 1985 and 1990 was 35.5 cases per 100,000 children aged less than 5 years; for H influenzae type b meningitis it was 25.1 per 100,000 children aged less than 5 years. The cumulative risks for invasive disease and meningitis by the fifth birthday were one in 560 and one in 800 respectively. The majority of disease (71%) occurred in children less than 2 years of age with the peak monthly incidences at 6 and 7 months of age. The overall mortality was 4.3% and 50% of these deaths occurred suddenly. Most (91%) of the children had received at least one primary immunisation against diphtheria, tetanus, and pertussis before H influenzae type b infection and there was only one case of parental refusal of immunisation. None had received H influenzae type b immunisation. Given a vaccine uptake of 90% by 5 months of age it is estimated that at least 82% of the H influenzae type b infections could have been prevented. Extrapolated nationally, 1150 cases of infection and 50 deaths could be prevented each year by routine primary immunisation. 相似文献
65.
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
66.
67.
68.
Blood transfusion costs: a multicenter study 总被引:5,自引:0,他引:5
JM Forbes ; MD Anderson ; GF Anderson ; GC Bleecker ; EC Rossi ; GS Moss 《Transfusion》1991,31(4):318-323
The cost of delivering a unit of blood (whole blood or red cells) to a hospitalized patient was examined in 19 United States teaching hospitals. The average hospital acquisition cost was calculated by using the prices charged by regional blood centers for blood products. To this cost was added an estimate of costs incurred by hospitals for handling, testing, and administering blood. Across study sites, the average hospital cost per unit transfused was $155 and the average charge to the patient was $219. Acquisition cost, the price that hospitals pay for blood, was 37 percent of the total cost to the hospital; the other 63 percent of the hospital cost included costs for blood bank handling (13%), laboratory tests (43%), and blood administration (7%). Significant variations in blood transfusion cost were found within our sample. Most of the variability can be attributed to geographic location of the blood supply source, type of red cell product transfused, prices charged by blood transfusion services, and the frequency of laboratory tests. The results of this transfusion cost study may be helpful in determining the costs of health care delivery, especially when blood transfusions are indicated. 相似文献
69.
Recombinant human interleukin-1 receptor antagonist in the treatment of steroid-resistant graft-versus-host disease 总被引:11,自引:1,他引:11
Antin JH; Weinstein HJ; Guinan EC; McCarthy P; Bierer BE; Gilliland DG; Parsons SK; Ballen KK; Rimm IJ; Falzarano G 《Blood》1994,84(4):1342-1348
Acute graft-versus-host disease (GVHD) that is resistant to therapy is a highly lethal complication of marrow transplantation. Inflammatory cytokines such as interleukin-1 (IL-1) may be critical mediators of this process. If so, specific inhibition of IL-1 activity with recombinant human IL-1 receptor antagonist (IL-1Ra), a naturally occurring competitive inhibitor of IL-1, may ameliorate acute GVHD. We performed an open-label, phase I/II trial to evaluate the safety and efficacy of IL-1Ra in 17 patients with steroid-resistant GVHD. The IL- 1Ra was administered as a 24-hour continuous infusion over 7 days. The dose was escalated in cohorts of patients from 400 to 3,200 mg/d. Acute GVHD was evaluated in each affected organ and as an overall grade. Stage-specific improvement of acute GVHD occurred in the skin (8 of 14, 57%), gut (9 of 11, 82%), and liver (2 of 11, 18%). Overall, acute GVHD improved by at least one grade in 10 of 16 (63%) patients. Response to therapy was associated with a reduction of tumor necrosis factor-alpha (TNF-alpha) mRNA levels in blood mononuclear cells (P = .001). The only toxicity attributable to IL-1Ra was reversible transaminase elevation in two patients. Inhibition of IL-1 activity with IL-1Ra is safe and has demonstrable efficacy in acute GVHD that failed to respond to conventional treatment. These data provide further evidence that IL-1 is a mediator of GVHD. 相似文献
70.
Interleukin-3 expression by activated T cells involves an inducible, T- cell-specific factor and an octamer binding protein 总被引:2,自引:0,他引:2
Interleukin-3 (IL-3) is exclusively expressed by activated T and natural killer cells, a function that is tightly controlled both in a lineage-specific and in a stimulation-dependent manner. We have investigated the protein binding characteristics and functional importance of the ACT-1-activating region of the IL-3 promoter. This region binds an inducible, T-cell-specific factor over its 5' end, a site that is necessary for the expression of IL-3 in the absence of other upstream elements. Over its 3' end, it binds a factor that is ubiquitously and constitutively expressed. This factor is Oct-1 or an immunologically related octamer-binding protein, and it plays a role in coordinating the activity of several regulatory elements. These characteristics make the ACT-1 site analogous to the activating ARRE-1 site in the IL-2 promoter. Furthermore, and despite a lack of sequence homology, the promoters of IL-3 and IL-2 share an organizational pattern of regulatory elements that is likely to be important for the T- cell-specific expression of these genes. 相似文献