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Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence. 相似文献
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D Rudman A G Feller H S Nagraj D L Jackson I W Rudman D E Mattson 《JPEN. Journal of parenteral and enteral nutrition》1987,11(4):360-363
Serum albumin was measured in 126 men (average age 70.6; range 40 to 96) of a Veterans Administration Nursing Home, and was correlated with other items in an extensive clinical data base, including death or survival during the year after the analysis. The reason for institutionalization was chronic neurologic disease or other disabling physical condition in 63 men (group A), and psychiatric disorder in 63 men (group B). In group A, the proportions of men with albumin less than 3.5, 3.5-4.0, and greater than 4.0 g/dl were 6%, 37%, and 57%, respectively. In this group, the serum albumin level was significantly (p less than 0.05) correlated with death rate, hemoglobin, hematocrit, serum cholesterol, and serum lactic dehydrogenase. The death rate in group A during the year after the albumin analysis was 25%. For the patients with albumin level less than 3.5, 3.5-4.0, and greater than 4.0 g/dl, the death rates were 50%, 43%, and 11% respectively (p less than 0.01 for comparison of the former two groups with the latter). The subgroup with albumin 3.5-4.0 g/dl represented only 37% of the men in group A, but accounted for 63% of the group's deaths. In group B, serum albumin level was not significantly correlated with any other clinical variable. Death rate during the year after the albumin analysis was only 2% in group B, and did not correlate with the albumin level. These data indicate that, in nonpsychiatric Nursing Home men, the desirable level for the serum albumin concentration is higher than 3.5 g/dl. 相似文献
4.
A Thurkauf B de Costa M V Mattson C P France M T Price J W Olney J H Woods A E Jacobson K C Rice 《Journal of medicinal chemistry》1990,33(8):2211-2215
A series of 1-[1-arylcyclohexyl]-1,2,3,6-tetrahydropyridines were prepared by the reaction between 1-(1-cyanocyclohexyl)-1,2,3,6-tetrahydropyridine (1) and an appropriately substituted Grignard reagent. The resulting compounds were tested for their phencyclidine binding site affinities. Selected compounds were then tested for their ability to produce ketamine appropriate responding in monkeys and/or to show neuroprotective effects in a baby rat hypoxia/ischemia model. While it was found that binding site affinity correlated well with discriminative stimulus effects, it was found to be a poor indicator of neuroprotective efficacy within this series. 相似文献
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Prognostic significance of serum cholesterol in nursing home men 总被引:2,自引:0,他引:2
D Rudman D E Mattson H S Nagraj A G Feller D L Jackson N Caindec I W Rudman 《JPEN. Journal of parenteral and enteral nutrition》1988,12(2):155-158
Serum cholesterol was measured in 129 men (average age 70.6; range 41-96) of a Veterans Administration Nursing Home, and was correlated with other items in an extensive clinical data base. Serum cholesterol was less than 150 mg/dl in 13% of the subjects, and was less than 160 mg/dl in 18%. Cholesterol greater than 280 mg/dl occurred in 8%. Serum cholesterol varied directly (p less than 0.02) with: body weight, serum albumin, serum total protein, serum sodium, ability to walk, and ability to feed oneself; and indirectly (p less than 0.02) with death rate, degree of functional dependence, and serum SGOT and LDH. Nursing home men with cholesterol less than 150 mg/dl had a death rate of 63% during the 14 months after the cholesterol analysis, compared to a death rate of 9% in men with cholesterol greater than 150 mg/dl (p less than 0.05). Death rate during the year after the analysis was 52% if cholesterol was below 160 mg/dl, compared to 7% if it was above this threshold (p less than 0.05). 相似文献
7.
David L. Mattson Shanhong Lu Allen W Cowley Jr 《Clinical and experimental pharmacology & physiology》1997,24(8):587-590
1. Nitric oxide (NO) has been implicated as an important controller in the short- and long-term regulation of arterial pressure. Studies performed in our laboratory have demonstrated that chronic intravenous administration of the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) selectively decreases renal medullary blood flow, causes sodium and water retention and leads to hypertension. 2. To determine the importance of the renal medullary effects in this model of hypertension, further studies were conducted to examine the influence of selective stimulation or inhibition of renal medullary NO on whole kidney function and cardiovascular homeostasis. With the use of a unique catheter to directly infuse into the renal medullary interstitial space, stimulation (bradykinin or acetylcholine) or inhibition (L-NAME) of renal medullary NO selectively increased or decreased renal medullary blood flow. 3. The changes in medullary flow in these experiments were associated with parallel changes in sodium and water excretion independent of alterations in renal cortical blood flow or glomerular filtration rate. 4. Studies were then undertaken to examine the long-term effects of selective NO inhibition in the renal medulla on cardiovascular homeostasis. Chronic infusion of L-NAME directly into the renal medullary interstitial space of uninephrectomized Sprague-Dawley rats led to a selective decrease in renal medullary blood flow that was sustained throughout the 5 day L-NAME infusion period. The decrease in medullary blood flow was associated with retention of sodium and the development of hypertension and the effects were reversible. 5. The data reviewed indicate that NO in the renal medulla has a powerful influence on fluid and electrolyte homeostasis and the control of blood pressure. 相似文献
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M P Mattson 《Neurobiology of aging》1991,12(4):343-6; discussion 352-5
The maintenance and adaptive plasticity of neural circuitry requires the coordinated activities of an array of signal transduction systems. These different signalling systems play critical roles in carving out and modifying functional neural circuitry in development and adult plasticity. Ironically, aberrant activity in these systems may sever neural connections and take the lives of neurons in a variety of disorders including Alzheimer's disease. A rather complex set of circumstances must be taken into account when considering the consequences of activity in pathways that regulate neuroarchitecture. The specific signalling pathways activated, their levels of activation, activity in other pathways, and environmental conditions are among the factors that enter into the equation for determining whether use is a boon or a bane. 相似文献