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11.
AIM: The aim of this study was to investigate the nature and organization of maternal needs and priorities in a neonatal unit. BACKGROUND: The relationship between maternal needs and priorities appears to be an under studied area in neonatal nursing. METHODS: A quantitative survey was carried out based on 209 mothers with premature infants. Two self-assessment schedules were used: critical care maternal needs inventory (J. Leske, Heart and Lung 15, 27-42) and a ranking scale. The data were analysed with multivariate analysis. FINDINGS: Data analysis revealed clear priorities in maternal needs. In particular the need for accurate infant related information was a priority for 93% of the mothers. Good communication practices with professionals were also valued. The mothers displayed altruistic behaviour, and self-related needs took second place. It is proposed that maternal needs demonstrate a hierarchical organization. CONCLUSION: It is important for nurses to consider the individual needs of the mothers, simply because the satisfaction of these needs is essential for maternal well-being.  相似文献   
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The administration of protamine sulfate for the reversal of heparin anticoagulation has been associated with adverse hemodynamic changes including hypotension and decreased cardiac output. The possible direct toxic effect of protamine on human right atrial trabeculae contracting isometrically in vitro was studied. Muscles were stimulated to contract at 1 Hz in Tyrode's solution (maintained at 34 degrees C, pH 7.4) into which protamine was continuously added. Following a polynomial regression analysis, a parabolic dose-response curve resulted. The equation was: y = 95.13 + 38.76x - 278.71x2 where y = relative developed force and x = concentration of protamine (milligrams per milliliters) (r = 0.82). The estimated concentration of protamine resulting in 50% developed force was 0.48 mg/ml. In a second series of experiments, protamine was added to the bath along with a neutralizing amount of heparin. This resulted in a limited reduction in the fall of relative developed force. Thus, protamine in high concentrations alone or in complex with heparin has a direct toxic effect on human myocardial muscle mechanics, and care is warranted in its clinical use.  相似文献   
13.
Combinations of murine recombinant interleukin 3 (IL-3), purified murine macrophage colony-stimulating factor (M-CSF), and human recombinant interleukin 1 alpha (IL-1 alpha) were used to determine the effects of growth factors on the measured radiosensitivity of different populations of murine colony-forming cells (CFC). The data showed that combinations of growth factors resulted in different values of CFC radiosensitivity, being less than values observed when colony growth was stimulated using a single factor. For various combinations of growth factors, Do values ranged from 106 +/- 8 to 175 +/- 24 cGy for progenitor cells in normal bone marrow; 74 +/- 3 to 171 +/- 18 cGy for primitive multipotent CFC enriched using fluorescence-activated cell sorting; and from 46 +/- 4 to 131 +/- 10 cGy for more mature granulocyte-macrophage CFC, enriched by counterflow centrifugal elutriation. Only combinations of three factors produced the high values of Do reported in experiments using unpurified conditioned medium as a stimulus for colony formation.  相似文献   
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Seminal analysis was performed within 2 months of orchiectomy on 97 patients with clinical Stage I malignant testicular teratoma managed by surveillance following orchiectomy. Relapse of malignant disease occurred in 28% of 47 patients with a sperm count less than 10 X 10(6)/ml and in 32% of 50 patients with a sperm count greater than or equal to 10 X 10(6)/ml. Of 11 patients with azoospermia, 4 relapsed and 1 developed contralateral testicular germ cell tumour. Of 35 patients with malignant teratoma undifferentiated the relapse rate was 68% in 16 patients with a sperm count less than 10 X 10(6)/ml and 42% in 19 patients with a sperm count greater than or equal to 10 X 10(6)/ml. It was concluded that sperm count analysis is non-contributory in estimating the risk of relapse in clinical Stage I teratoma.  相似文献   
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Leukemia inhibitory factor (LIF), a peptide growth factor with multiple activities, has recently been shown to support the generation and survival of sensory neurons in cultures of mouse neural crest and dorsal root ganglia (DRG). We have conducted binding experiments with 125I-LIF on cultures of DRG to determine the receptor distribution for LIF on these cells and found that at least 60% of the sensory neurons in the cultures bound 125I-LIF, all of which could be eliminated by the addition of unlabeled LIF. The other cells in the culture, which morphologically appeared to be Schwann cells, did not bind appreciable quantities of 125I-LIF. In order to investigate whether LIF is retrogradely transported to sensory neurons in vivo, 125I-LIF was injected into the footpads and gastrocnemius muscles of newborn and adult mice, following sciatic nerve ligation. Radioactivity accumulated in the distal portion of the sciatic nerve, indicating retrograde transport of LIF. Subsequent experiments on mice with unligated sciatic nerves showed that 125I-LIF is specifically transported into the sensory neurons of the DRG. There was no apparent transport of 125I-LIF into motor neurons in the spinal cord. These experiments demonstrate that LIF can specifically bind to and be transported by sensory neurons and further support the idea that LIF acts as a target-derived neurotrophic factor, analogous to NGF.  相似文献   
18.
A monoclonal antibody capable of blocking the biological activity of the ciliary neurotrophic factor purified from bovine cardiac muscle has been produced. This antibody, when administered perinatally to mice, causes a failure of the normal development of the parasympathetic innervation of the iris as determined by assay for the activity of the cholinergic marker enzyme choline acetyltransferase. The same treatment has no effect on the adrenergic neuronal marker, tyrosine hydroxylase. This immunoparasympathectomy suggests that the ciliary neurotrophic factor has an essential role in regulating the development of the mammalian parasympathetic nervous system.  相似文献   
19.
An Australian school of nursing's attempt to introduce an evaluation process required by management for clinical educators involved in undergraduate preregistration education is discussed Reliance on student feedback and clinical agencies' perceptions of the quality of teaching were seen as inadequate mechanisms for evaluation The evaluation process adopted incorporated observation of the educators together with self-reflection on their performance We conclude that post-briefings were poorly used and generally not reflective Educators relied heavily on their clinical skills and used a limited range of teaching strategies Whilst evaluation of clinical educators was time consuming and therefore costly, it is argued that it is essential to the integrity of the course The evaluation process has provided direction for support and development of clinical educators within the context of the curriculum  相似文献   
20.
Although myocardial toxicity of certain antibiotics has been suggested by animal studies, their effects on human cardiac muscle has not been established. Accordingly, human right atrial trabeculae contracting isometrically in vitro were exposed to increasing doses of the antibiotics gentamicin, tobramycin and cephalothin. Contractile responses were measured and dose-response curves calculated by a polynomial regression analysis. All three antibiotics demonstrated a dose-related decrease in relative developed force although resting force remained constant. Concentrations of gentamicin, tobramycin and cephalothin that caused 50% depression of developed force were 1.97, 1.92 and 52.75 mg/mL, respectively. These doses were 200, 200 and 2600 times the accepted serum toxic concentrations for gentamicin, tobramycin and cephalothin, respectively. The depression caused by cephalothin is probably related to ionic changes within the bath solution. In conclusion, gentamicin and tobramycin have myocardial toxicity at high concentrations which should not occur clinically when used judiciously.  相似文献   
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