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101.
The effect of propranolol on precordial ST-segment elevation was studied in 24 patients with acute anterior myocardial infarction. The electrocardiographic response to the drug was correlated with the early angiographic appearance of the left anterior descending coronary artery (LAD). After a 30-minute observation period, intravenous propranolol (average dose 3.5 +/- 2.2 mg) was given a mean of 2.8 +/- 1.9 hours after the onset of persistent chest pain. Coronary angiography was performed 3.6 +/- 2.0 hours after the onset of symptoms. Patients were classified into 2 groups according to the angiographic findings. Group A consisted of 7 patients with a stenotic but patent LAD and 1 patient with excellent collateral blood flow to that area. Group B consisted of 16 patients with a completely occluded LAD and poor or absent collateral blood flow. Patients in group A showed a mean reduction in precordial ST-segment elevation of 77 +/- 18% and patients in group B showed a mean reduction of 13 +/- 14% (p less than 0.005). Left ventricular ejection fraction at discharge was 0.6 +/- 0.07 in group A and 0.37 +/- 0.08 in group B (p less than 0.001). Thus, the electrocardiographic response to intravenous propranolol given early in the course of acute anterior myocardial infarction predicts the presence of blood flow to the infarcting zone. The combination of residual blood flow and reduction of ST-segment elevation secondary to propranolol is associated with preservation of ventricular function.  相似文献   
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The frequency, nature, context, and caregivers' reactions to aggressive behavior in 213 dementia patients residing in the community was studied. Aggression was reported in 57.2% of the patients and in 10.6% of the caregivers. Predictors of patient aggression were greater frequency of behavior and memory problems, premorbid aggression, and a more troubled premorbid social relationship between patient and caregiver. Patient aggression predicted the decision to discontinue home care.  相似文献   
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Summary The carcinogenicity of the -dipropylnitrosamine (DPN) methylether, 1-methoxypropylpropylnitrosamine (1-MPPN), was investigated in Syrian hamsters for comparison with the effect of the -DPN acetylester, 1-acetoxypropylpropylnitrosamine (1-APPN). It seemed possible that 1-MPPN, 1-APPN and DPN could form a common intermediate. However, contrary to the effect of 1-APPN, no tumors were found at the injection site after subcutaneous 1-MPPN treatment. The main target organ for 1-MPPN was the respiratory tract (as with DPN) and the lungs were greatly affected. In addition, pharyngeal and forestomach tumors occurred, and these were not observed after DPN administration. The results of 1-MPPN treatment, relative to DPN and 1-APPN, are discussed.
Die Wirkung von 1-Methoxypropylpropylnitrosamin bei Syrischen Goldhamstern
Zusammenfassung Die carcinogene Wirkung des -Dipropylnitrosamin (DPN) Methyläthers, 1-Methoxypropylpropylnitrosamin (1-MPPN), wurde bei Syrischen Hamstern untersucht. Die Wirkung wurde mit der des -DPN Acetylesters, 1-Acetoxypropylpropylnitrosamin (1-APPN), verglichen. Es erschien möglich, daß 1-MPPN, 1-APPN und DPN einen gemeinsamen Metaboliten bilden. Im Gegensatz zu der Wirkung von 1-APPN fanden sich jedoch keine Tumoren an der Injektionsstelle nach subcutaner Behandlung mit 1-MPPN. Vorwiegend war der Respirationstrakt betroffen (wie bei DPN), wobei eine starke Wirkung auf die Lungen beobachtet wurde. Darüber hinaus entstanden Tumoren in Pharynx und Vormagen, die nach Verabreichung von DPN nicht erschienen. Die Befunde nach 1-MPPN Behandlung wurden in Verbindung mit der Wirkung von DPN und 1-APPN diskutiert.


Supported by US Public Health Service contract NO1 CP33278 from the Division of Cancer Cause and Prevention, the National Cancer Institute, NIH, and by Public Health Service grant No. 1 RO1 CA14659 awarded by the National Cancer Institute, DHEW  相似文献   
106.
Simultaneous primary malignancy of the lung and kidney has been rarely recognized during life. Three patients with synchronous primary pulmonary and renal cancer are described. The pulmonary tumors were asymptomatic and were discovered on plain chest roentgenography. The renal tumors, also asymptomatic, were incidentally discovered on CT, performed for staging. Although one patient was treated with interleukin-2 for a presumed solitary pulmonary metastasis from renal carcinoma, in all three patients, both the kidney and lung tumors were eventually removed either concurrently or sequentially. Prior autopsy case series are reviewed. In the elderly, synchronous asymptomatic pulmonary and renal malignancy is not surprising, and it should be approached as a distinct clinical problem. With the use of chest roentgenography for screening high risk populations and CT for staging, simultaneous primary pulmonary and renal malignancy will probably be recognized increasingly.  相似文献   
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The radioimmunoassay technique, first developed for the determination of hormones, has been applied to many substances of biologic interest by clinical and research laboratories around the world. It has had an enormous effect in medicine and biology as a diagnostic tool, a guide to therapy, and a probe for the fine structure of biologic systems. For instance, the assays of insulin, gastrin, secretin, prolactin, and certain tissue-specific enzymes have been invaluable in patient care. Further refinements of current methods, as well as the emergence of new immunoassay techniques, are expected to enhance precision, specificity, reliability, and convenience of the radioimmunoassay in both clinical and research laboratories.  相似文献   
110.
Older adults, individuals with dementia of the Alzheimer's type (DAT), and individuals with semantic dementia (SD) produced the past tense of verbs based on present-tense carrier sentences (e.g., Everyday I ding the bell. Yesterday I_____the bell). Both regularity (i.e., whether or not -ed is used for the past tense) and consistency (i.e., the degree to which verbs of similar orthography and phonology in the present tense have similar past tenses to the target) were manipulated. Participants received regular consistent (e.g., land–landed), regular inconsistent (e.g., weed–weeded), irregular consistent (e.g., sting–stung), and irregular inconsistent (e.g., light–lit) verbs. The dependent measures were overall accuracy rates and error rate types (e.g., regularizations, analogies, and other errors). Both consistency and regularity influenced performance. In addition, individuals with DAT showed a disproportionate deficit for inconsistent verbs associated with a high summed frequency of enemies, whereas SD individuals produced disproportionate breakdowns in performance on regular inconsistent, irregular consistent, and irregular inconsistent verbs. These results are consistent with the perspective that semantic/lexical processes are involved in processing the past tense of both irregular verbs and regular inconsistent verbs, and that attention is used to select appropriate responses and control inappropriate responses.  相似文献   
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