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991.
In this study the utility of operative ultrasound in the surgical management of 98 consecutive patients with liver and gastrointestinal tumors was assessed. All patients had preoperative work-up including ultrasound study of the liver as well as selective hepatic arteriography (50 patients) and computerized tomography of the liver (45 patients). At surgery, inspection and palpation of the liver as well as operative ultrasound examination were performed in all cases. Fifty-six patients were known to have liver tumors before operation, while 42 patients had their liver examined as part of the treatment of a primary gastrointestinal malignancy. A total of 126 liver tumors were found in 58 patients, all of whom were confirmed histologically. Eighteen nodules unsuspected before operation were found at surgery--nine by inspection and palpation of the liver, and nine others that were nonpalpable were found by operative ultrasound only. Eighteen lesions that were missed by all diagnostic modalities were found as secondary lesions on pathologic examination of the resected specimens. In addition to diagnostic applications, operative ultrasound was useful in localizing nodules and permitting guided biopsies deep in the hepatic parenchyma. In eight cases, segmental resections were performed with operative ultrasound to localize the plane of section and to catheterize the intrahepatic portal vein branch afferent to the tumor in order to perform balloon catheter occlusion of the vessel for control of bleeding. Operative ultrasound was found to be important in the surgical management of 19 of 98 patients (19%).  相似文献   
992.
A 68 year-old woman presented with a two-week history of amaurosis fugax, ipsilateral fronto-temporal headache and jaw claudication suggesting carotid giant cell arteritis. However, this syndrome proved to be due to atherosclerosis causing complete occlusion of the external carotid artery at its origin and narrowing of the internal carotid artery. Combined external and internal carotid endarterectomy relieved the symptoms. The symptom complex of temporal arteritis may be rarely mimicked by carotid atherosclerotic occlusive disease.  相似文献   
993.
Numerous surveys at the national and regional level have demonstrated that large inequalities in infant health status exist in Southern Africa. Few studies have assessed infant mortality at the intra-urban scale of geographic analysis. Comparisons between infant mortality rates from different areas are made even more meaningful if the data are divided into two primary categories based on period-of-death; these being the neonatal and post-neonatal components. This study presents the results of a survey undertaken in Metropolitan Cape Town (population 1.6 million) during 1982. The aim was to determine the spatial variation of neonatal and post-neonatal mortality at the suburb (or community) level within the city. Overall, a total of 36,789 live births and 928 infant deaths were recorded; 53.4% in the neonatal period and 46.6% in the post-neonatal period. The mean infant mortality rate was 25.2 per 1000 live births; the neonatal mortality rate and post-neonatal mortality rate being 13.5/1000 and 11.7/1000, respectively. A marked range in death rates was evident for both components. For the neonatal category it was 0.0-49.9/1000 and 0.0-40.0/1000 for the post-neonatal period. The generally low post-neonatal mortality rate among the 69 suburbs studied has made the neonatal component the dominant contributor to the infant mortality rate. However, in the lowest socio-economic areas the post-neonatal mortality rate was responsible for over 60% of infant deaths.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
994.
This paper describes a method for the detection of Entamoeba histolytica antigens in stool samples using a multi-layer ELISA. The method is sensitive and specific, showing no interference with other intestinal parasites, e.g. E. coli, E. hartmanni, Endolimax nana, Iodamoeba buetschlii, Hymenolepis nana, Giardia lamblia, Trichomonas and Ascaris. The method provides a rapid and simple screening assay for E. histolytica infections and should assist in diagnosis and epidemiological studies of the disease.  相似文献   
995.
The effects of danazol on calcium homeostasis in normal postmenopausal women was examined in a 14-day study utilizing a dosage of 800 mg per day. Danazol caused significant falls in plasma ionized calcium and in the fasting urinary calcium/creatinine ratio, indicating inhibition of bone resorption. Retention of phosphate was also observed as expected with this anabolic agent. The plasma total alkaline phosphatase was also depressed by the drug, which had no effect on hepatocellular function as measured by plasma AST. Certain effects induced by treatment with danazol were still apparent two weeks after cessation of treatment. The drug was well tolerated and androgenic side effects were not seen. It is suggested that the minimal dose regimen of danazol which exerts a calcium-sharing effect should be identified, and that this regimen should be considered for use in a prospective study of the effects of danazol on bone mineral content in the postmenopause.  相似文献   
996.
During 1983 and 1984, 1305 patients underwent 1,400 pulmonary artery (PA) catheterizations. Successful placement was achieved in 1397 (99.6%) of 1,403 attempts. The catheters were inserted via the right internal jugular vein on 1364 occasions. The median duration of monitoring was 28 h with a range from 3 to 220 h. Central venous puncture complications included carotid artery puncture in 67 instances (4.8%) and pneumothorax in one patient. Insertion of the catheters was associated with supraventricular arrhythmias on 11 occasions, ventricular arrhythmias on 930 (66.4%), right bundle branch block on two and a total heart block on one occasion. Eighteen (2.3%) of the 794 cultured catheter tips were positive. An in situ time of more than 72 h was associated with a significantly higher percentage (7.2%) of positive tip cultures compared with an in situ time of less than 72 h (P less than 0.01). Repeated PA catheterization was not associated with significantly more complications than the initial catheterization. The results show that monitoring with a PA catheter in cardiac surgical patients is associated with a low incidence of morbidity.  相似文献   
997.
998.
Behavioral state-specific changes in human hippocampal theta activity   总被引:1,自引:0,他引:1  
Although there has been extensive examination of the behavioral and physiologic correlates of hippocampal theta activity in animals, the human literature consists of a single case study. We investigated the differential effects of four behavioral states on human hippocampal theta activity in 16 epilepsy surgery patients. Behavioral conditions included resting eyes closed (RC), resting eyes open (RO), eyes open with auditory word activation (AW), and eyes open with visuospatial activation (VS). Hippocampal theta activity decreased during both RO and VS compared to both RC and AW. There were reciprocal changes in delta activity. Comparisons of RO to VS and of RC to AW were nonsignificant. The results demonstrate state-specific changes in human hippocampal theta and are consistent with the animal literature that relates hippocampal theta to sensorimotor integration and forebrain volitional mechanisms.  相似文献   
999.
The primary antigen-specific antibody response of various strains of mice to TEPC-15/PnC immune complexes has been examined. We found that both BALB/c and C3H mice were good responders to the PnC antigen; however, C3H mice were low responders, whereas BALB/c mice were high responders to the TEPC-15/PnC complexes. Using congenic strains on the C3H and BALB/c background, we have shown that the response to the complexes is not restricted by gene products of the H-2 complex or by the Igh (allotype) locus. However, responsiveness may be controlled by genes linked to the Igh locus, since we have shown that strains that are Ighj, Ighd, and Ighf are low responders, whereas strains that are Igha, Ighb, and Ighe are high responders to the immune complex. Moreover, responsiveness correlates with the expression of the T15 Id as measured using the anti-T15 monoclonal antibody, AB1-2. Thus, strains such as BALB/c, BALB.B, BALB.K, and CB-20, which express high levels of T15 (AB1-2) Id in their PFC response to PnC are relatively high responders to TEPC-15/PnC complexes, whereas C3H, C3H.SW, and C3H-OH, which express low levels of the T15 (AB1-2) Id, are low responders to the complexes. Finally, we found that BALB/c mice are high responders to complexes formed with T15+ antibodies, whereas they are low responders to complexes formed using T15- antibodies. The results suggest that the antigen-specific response to these immune complexes is Id-restricted.  相似文献   
1000.
The aim of the present study was to present data from dental care habits and knowledge of oral health in two cross-sectional studies carried out in 1973 and 1983. A random sample of approximately 1000 individuals evenly distributed in the age groups 3, 5, 10, 15, 20, 30, 40, 50, 60 and 70 years was studied for each of these two years. In the 1983-year examination 80 individuals 80 years of age were also included. All subjects were inhabitants of the community of J?nk?ping, Sweden. A questionnaire about dental care habits and knowledge was used in combination with a clinical and radiographical examination. The participants answered 23-101 questions. The same questions were raised in 1973 and 1983. For most age groups more then 80 per cent visited a dentist yearly in 1983. This yearly attendance was higher than that for 1973. In the 20-year-old group 14 per cent of the individuals received dental care in the PDS in 1973 compared to 63 per cent in 1983. The main reason to visit a dentist in 1973 was by the patient's own initiative while in 1983 the appointments were based on the dentist's initiative. The number of subjects that felt discomfort in connection with a visit to the dentist had decreased between 1973 and 1983. Knowledge about the etiology of caries had increased between 1973 and 1983 was not the case for gingivitis and periodontitis. An increase had occurred in toothbrushing frequency and the use of toothpicks and disclosing tablets but this between 1973 and 1983. In 1983, 98 to 93 per cent of the subjects in the age groups 10-30 years had been exposed to topical fluorides. The corresponding figure for 30-year-olds in 1973 was 1 per cent. It is obvious that during the period 1973 to 1983 there has been an increase in dental attendance, knowledge of dental diseases, oral health and the use of preventive measures.  相似文献   
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