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91.
During normal pregnancy there is a decrease in the hematocrit due to a disproportionate increase in the blood volume compared with the red cell mass. Using a new enzyme-linked immunoassay (Amgen Diagnostics), serum erythropoietin was quantified in normal nonanemic pregnancies throughout gestation and in third trimester anemic patients. We found that the mean hematocrit in normal pregnancy reached a nadir late in the second trimester and the serum erythropoietin plateaued at a 50% increase. Those pregnancies complicated by anemia defined by a hematocrit less than 30 vol% demonstrated a statistically significant increase in serum erythropoietin above those not anemic. 相似文献
92.
Samuel E. Lynch DMD DMSc ; Stephen B. Trippel MD ; Richard D. Finkelman DDS PhD ; Rafael A. Hernandez DMD ; Christopher P. Kiritsy BA ; Harry N. Antoniades PhD 《Wound repair and regeneration》1994,2(3):182-190
The combination of insulin-like growth factor-I and platelet-derived growth factor-BB has previously been shown to stimulate healing of soft tissue wounds and the formation of bone and ligament around teeth. The purpose of the present study was to evaluate the effects of platelet-derived growth factor-BB and insulin-like growth factor-I individually and in combination on the healing of osseous wounds. Four standardized cortical wounds were created in each tibia of 11 adult Yucatan miniature pigs. The wounds in one tibia per animal were treated with either purified recombinant human insulin-like growth factor-I, platelet-derived growth factor-BB, or both in a methylcellulose gel. The wounds in each contralateral tibia received placebo gel alone. Coded serial sections of each wound were evaluated by computer-aided histomorphometry 21 days after surgery. The area and perimeter of the newly formed mineralized callus, the thickness of the total callus, and the percentage of mineralized tissue within the callus were significantly increased compared with the values of matched controls only in wounds treated with a combination of insulin-like growth factor-I and platelet-derived growth factor-BB. No significant differences in the measured parameters of callus formation were found in wounds treated with either insulin-like growth factor-I or platelet-derived growth factor-BB alone. Cartilage was present only in sites treated with insulin-like growth factor-I alone. These results suggest that the combination of platelet-derived growth factor-BB and insulin-like growth factor-I stimulates bone formation in wounds in long bones of adult animals and that these growth factors act via different pathways during the repair process. 相似文献
93.
OBJECTIVE: To appraise the measurement properties of the Canadian Cardiovascular Society (CCS) classification of stable angina pectoris. DATA SOURCES: Relevant articles were identified through a MEDLINE search (1976 to November 1991). Bibliographies of retrieved articles were also reviewed. STUDY SELECTION: Studies chosen directly addressed the validity and reliability of the CCS scale. Recent studies and reviews of related topics (for example, silent ischemia) are selectively cited. DATA SYNTHESIS: No data address the scale's applicability, that is, how clinicians typically assign angina grades in practice. Comprehensiveness would be improved by coverage of the patient's perceptions of symptom burden; mixed exertional and rest symptoms; episodic or changing symptoms; and modifying factors. Reliability was assessed in one study with two clinicians; the interobserver, chance-corrected agreement on patient grading was 60%. Content validity (the ability of the scale to measure what it claims) is threatened by the unproven assumption of symptomatic or physiologic equivalence among diverse levels of different activities within any given grade of angina. Construct validity is uncertain, given weak relations between angina grade and noninvasive markers of ischemia, anatomical disease, or prognosis. The scale's responsiveness (the ability to detect the smallest clinically important changes) is limited by the reliance on four coarse gradations based on only ambulation or stair-climbing. CONCLUSIONS: The CCS scale for stable angina might be made more useful by developing measurements for patients' self-rated symptom burden and the changes they deem important; by adding items on clinical instability (that is, progressive symptoms or pain at rest); and by empirically testing the current scale to eliminate redundant or inconsistent elements. 相似文献
94.
A questionnaire on anxiety disorder services was sent to 240 Canadian hospitals, of which 117 responded. Eighteen of the responding hospitals had anxiety disorder clinics and saw an average of 208 patients a year. These clinics appear to be scarce although, according to epidemiological studies, there is a high prevalence of anxiety disorders in the community. The specific diagnoses of the patients seen in the specialty clinics and the treatments offered generally followed international patterns. 相似文献
95.
The literature on group coping skills training is reviewed and a model involving the use of a wide range of coping strategies with patients heterogeneous in terms of presenting problem is advocated. This study evaluates the effect of such an approach with a chronic inpatient and day-hospital patient population (n = 36) presenting with problems of anxiety and depression. Results suggest that the use of such groups can facilitate the transition from hospital to community. Further they are associated with symptomatic improvement that is of clinical significance in up to 50% of cases, which is largely maintained at 1 year follow-up and which is associated with a positive change in social functioning. In the light of this experience suggestions are made regarding the screening of patients and ways of enhancing group cohesion. 相似文献
96.
P. H. Cox J. Verweij M. Pillay G. Stoter D. Schonfeld 《European journal of nuclear medicine and molecular imaging》1988,14(1):50-52
111In-antimyosin monoclonal antibody complex passes through damaged myocardial cell membranes and binds to the intracellular myosin. Normal myocardial and other muscle cells show no uptake.Rhabdomyosarcoma and Leiomyosarcoma cells also contain intracellular myosin.and the cell membrane permeability is greater than normal. Significant uptake of 111In-antimyosin was observed in patient with Leiomyosarcoma and Rhabdomyosarcoma suggesting that the reagent has a potential for the in vivo detection of these tumour types. Tumour to background ratios of 10:1 were measured in one case and in view of the fact that the site of accumulation is intracellular, antimyosin may have a potential as a carrier for therapeutic agents. 相似文献
97.
Patient teaching or patient counselling? 总被引:1,自引:0,他引:1
Careless or confused use of terms such as information giving, teaching and counselling may lead to inadequate understanding and practice. In view of the progress made in this area, designed to help patients cope with illness and treatment, this paper aims to clarify and identify similarities and differences between these activities and discuss their relevance for those in most need of these types of care. Having recognised the complexity and persistence of such needs, patients, their relatives and nurses should perhaps decide their respective roles and work towards improving the quality of and opportunities for such interventions. 相似文献
98.
99.
J Staessen A Amery W Birkenh?ger C J Bulpitt J Cox P de Leeuw P De Cort R Fagard A Fletcher F Forette 《Journal of cardiovascular pharmacology》1992,19(1):120-125
Syst-Eur is a multicenter placebo-controlled outcome trial designed by the European Working Party on High Blood Pressure in the Elderly to investigate the effect of antihypertensive treatment on the incidence of stroke in elderly patients with isolated systolic hypertension (ISH). Eligible patients must be at least 60 years old and have a systolic blood pressure averaging 160-219 mm Hg with a diastolic blood pressure less than 95 mm Hg. The present paper is an interim report on the first 316 patients randomized into this trial. The placebo (n = 170) and active treatment (n = 146) groups were similar at randomization with respect to age (73 +/- 8 years; mean +/- SD), sitting blood pressure (178 +/- 12 mm Hg systolic; 85 +/- 7 mm Hg diastolic), percentage of men (34%), and percentage of patients with cardiovascular complications (29%). After randomization blood pressure fell more (p less than 0.001) in patients on active treatment than in those in the placebo group (19 +/- 20 mm Hg systolic; 6 +/- 10 mm Hg diastolic vs. 7 +/- 19 and 1 +/- 10 mm Hg for sitting blood pressure). This first interim report on the Syst-Eur trial demonstrates that a multinational trial in elderly patients with ISH is feasible and that a significant blood pressure difference between the two treatment groups can be achieved and maintained. New centers are being recruited in order to randomize a total of 3,000 patients. 相似文献
100.
Most clinicians agree that psychological factors are important considerations in the evaluation and treatment of headache patients. There has been a lack of systematic research, however, that has examined the relationship between these variables. Attention to such factors may become a greater concern as the frequency of a patient's headaches increases, there is increased disability secondary to headaches, and/or there is an inadequate response to usually effective treatment. In addition, there is no consensus as to the proper method to assess psychopathology in headache patients. 相似文献