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51.
1. Canine jugular and femoral veins were studied to determine the possible importance of thromboxane (TXA2) and prostaglandin endoperoxides (prostaglandin H2, PGH2) in mediating bradykinin(BK)-induced contraction. 2. Isolated vein rings incubated in modified Krebs solution contracted to TXA2/PGH2 analogs SQ26655 and U44069 with potency of contraction exceeding that for BK. The potency ranking for both veins was SQ26655 greater than U44069 greater than BK greater than PGF2 alpha greater than TXB2 much greater than PGD2. 3. The cyclo-oxygenase inhibitors indomethacin (3 x 10(-7) M) and flufenamic acid (10(-5) M) reduced BK contractions without affecting those induced by noradrenaline (NA). 4. TXA2/PGH2 receptor antagonists SQ29548 (10(-8) M) and BM13177 (10(-6) M) strongly inhibited BK-induced tension. The action of antagonists was reversible with negligible influence on NA-elicited contraction. Selective removal of endothelium had no effect on BK-induced contraction or the action of the antagonists. 5. The thromboxane synthase inhibitors dazoxiben (10(-4) M) and CGS 12970 (10(-5) M) had no significant inhibitory effect on BK-induced tension. 6. These results suggest that in canine jugular and femoral vein, the action of BK is largely dependent upon stimulation of the cyclo-oxygenase pathway to produce PGH2 and possibly TXA2, which can activate a smooth muscle TXA2/PGH2 receptor to elicit vasoconstriction.  相似文献   
52.
Parish nurses are experienced registered nurses committed to helping people meet the health needs of their body, mind, and spirit. To fulfill this goal, parish nurses must be health educators and counselors, referral sources, facilitators, patient advocates, healthcare plan interpreters, and multitalented coordinators. The parish nurse uses the skill of nursing assessment of individual and congregational needs and matches the assessment findings to available resources. The parish nurse also advocates increased awareness of health-related issues that lead to earlier and more effective treatment and care. All ages benefit within a context of personal caring and attention offered by a parish nursing model that is often lacking from healthcare delivery systems. Congregations of all sizes, both urban and rural, have successfully started parish nurse programs. Parish nursing programs are a religious response to help bring wholeness and healing to the faith community. The purpose of this article is to explore parish nursing as it has evolved into a model of health care delivery contributing to the empowerment and health of both the individual and the community.  相似文献   
53.
The effect of total-lymphoid irradiation on survival of canine pancreas and kidney allografts was studied. TLI had a marked immunosuppressive effect as measured by in vitro immune responses and reduced circulating leukocytes. Despite the changes, median graft survival times for animals treated with 800 cGy (9 days) or 1800 cGy (9.5 days) were not significantly different from untreated control animals (7 days). The addition of low-dose antithymocyte globulin (10 mg/kg/day) on post-transplant days 0, 2, 4, 6, 8, and 10 had no measurable synergistic effect. Similarly, median segmental pancreas allograft survival times after 1700-2200 cGy of TLI treatment (16.5 days) were only marginally longer than those of untreated controls (9 days). The only animal to maintain a graft for greater than 200 days was matched to the donor in mixed lymphocyte culture (MLC). This animal was able to reject a third-party skin graft after 8 days while a graft from the original donor was still surviving after 21 days when the pancreas graft failed from a chronic-type rejection. These results indicate that TLI alone or in combination with ATG will not be predictably effective as a method of prolonging allograft survival. The role of matching major histocompatibility complex antigens in TLI treatment requires clarification.  相似文献   
54.
The effect of drug concentration and light on the compatibility and stability of cisplatin and fluorouracil in i.v. admixtures was studied. Two sets of admixtures were prepared in 0.9% sodium chloride injection in polyvinyl chloride bags--(1) cisplatin 200 micrograms/mL and fluorouracil 1,000 micrograms/mL and (2) cisplatin 500 micrograms/mL and fluorouracil 10,000 micrograms/mL. Half of the admixtures were protected from light. All admixtures were stored at room temperature (24-26 degrees C), and those admixtures not protected from light were stored under room fluorescent light. After visual inspection, the pH of each admixture was determined, and an aliquot was assayed for drug concentration using a stability-indicating high-performance liquid chromatographic assay. Over a four-hour period, no visual changes were observed and the pH changes observed were negligible. In admixtures containing the lower concentrations of cisplatin and fluorouracil, it took approximately 1.5 hours for the concentration of cisplatin to reach 90% of the initial concentration. By four hours (lower concentration range) and three hours (higher concentration range) after the admixtures were prepared, less than 75% of the initial cisplatin concentration remained. There was less than a 5% decrease measured in the fluorouracil concentrations over the observation time. Admixtures of cisplatin and fluorouracil in 0.9% sodium chloride injection at the concentrations evaluated in this study must be used within one hour of preparation, whether or not they are protected from light. Intravenous administration of fluorouracil and cisplatin by continuous infusion will require alternative approaches to mixing the two drugs in the same container.  相似文献   
55.
Although most teratogens are suspected to act early in the first trimester of pregnancy, birth defects monitoring programs and etiologic studies usually use residence at birth as a proxy measure for residence in the first trimester in searching for environmental teratogens. Because of the high mobility of the U.S. population, residence misclassification can potentially alter inferences concerning environmental teratogens. To evaluate this potential bias, data from the population-based Maryland Birth Defects Reporting and Information System were analyzed. In 1984, the system ascertained 295 infants with one or more of 12 sentinel defects. Of these cases, 59 (20%) mothers reported they have changed address between the time of conception and the time of birth, and 22 have moved to a different county. The residential mobility rate varied by demographic variables and was highest among white women, in the age group 20-24 years. If residence at birth is used as a screening test for residence at conception, it can be shown that in the presence of an environmental teratogenic exposure, misclassification of exposure increases with increasing mobility rate, and population exposure frequency. Such misclassification tends to weaken associations between residence and birth defects and may lead to missing environmental teratogens. This analysis emphasizes the need to use residence information early in pregnancy rather than exclusively at birth.  相似文献   
56.
Rats given one or two 5-min trials in the elevated plus-maze had plasma corticosterone concentrations significantly higher than the home cage control group and there was no sign of habituation in the group given two trials. In rats given two plus-maze trials the corticosterone responses were significantly higher in the group given 10-min rather than 5-min trials. A previous experience of cat odour (1 week earlier) has no effect on the plasma corticosterone response, but did have an anxiogenic effect that could be detected by a decrease in the percentage of time spent on the open arms of the plus-maze. The results are discussed with reference to the nature of anxiety generated by trials 1 and 2 and by the trial duration in the plus-maze, and with respect to dissociation between behavioural and endocrinological measures.  相似文献   
57.
Renal and urological anomalies in Down syndrome (DS) have received little attention compared with the nephrourological findings described in other chromosomal abnormalities. Renal hypoplasia, hydroureteronephrosis, ureterovesical and ureteropelvic junction obstruction, and vesicoureteral reflux, but not posterior urethral valves, have been associated with DS. We report the occurrence of posterior urethral valves in three male infants with DS at a single institution. All had multiple urological procedures for correction or palliation of obstruction. Children with DS may have an increased risk for developing posterior urethral valves and obstructive uropathy. Furthermore, they may also develop chronic renal failure secondary to posterior urethral valves. Therefore, we suggests that infants with DS be screened with ultrasonography for renal and urological abnormalities early in life and, if abnormal, a contrast voiding cystourethrogram be performed to rule out posterior urethral valves or other bladder or urethral abnormalities. A review of the renal and urological anomalies in DS reported in the literature since 1960 is presented.  相似文献   
58.
59.
Coronary heart disease is the leading cause of death in New Zealand. Death rates are higher among the Maori than the European population but rates have been declining in both groups over recent years. The occurrence of coronary heart disease among the Pacific Island population in New Zealand is unknown. Data from the National Health Statistics Centre (NHSC) and the Auckland coronary or stroke (ARCOS) study were used to describe the occurrence of coronary heart diseases among Pacific Island people. Age standardised mortality rates show that coronary heart disease is an important cause of death among Pacific Island men. Death rates have declined between 1973-77 and 1978-82 but this trend did not continue among men in the 1983-86 period. Age standardised mortality rates from coronary heart disease from the ARCOS data are 175/100,000 and 52/100,000 for Pacific Island men and women compared with 325/100,000 and 141/100,000 for Maori men and women. Age standardised rates for European men and women are 154/100,000 and 36/100,000 respectively.  相似文献   
60.
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