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961.
The effects of halothane (0.2%, 0.5%, and 1.0%) on the spinal dorsal horn wide dynamic range (WDR) neuronal activity was studied in either spinal cord intact or spinal transected cats. Extracellular activity was recorded in the dorsal horn from single WDR neurons responding to noxious and non-noxious stimuli applied to the cutaneous receptive fields on the left hind foot pads of intact or decerebrate, spinal cord transected (L 1-2) cats. When 10 micrograms of bradykinin was injected into the femoral artery ipsilateral to the recording site as the noxious test stimulus in the spinal cat, all of 7 WDR neurons gave excitatory responses which were not depressed by 0.2% and 0.5% halothane but were depressed significantly by 1.0%. On the other hand, when the injection of 10 micrograms of bradykinin into the femoral artery ipsilateral to the recording site was used in the intact cat, 7 of 14 WDR neurons (50%) gave excitatory responses, which were not depressed by 0.2% halothane but were significantly depressed by 0.5% and 1.0% halothane, and 7 of 14 WDR neurons (50%) gave inhibitory responses, which were significantly depressed by 0.2%, 0.5%, and 1.0% halothane. We have found that halothane reduces the excitation as well as the inhibition of dorsal horn WDR neuronal activity induced by bradykinin injection.  相似文献   
962.
In human plasma, heparin cofactor II (HCII) is a thrombin inhibitor which displays similarities with antithrombin III (ATIII). As previously reported for hereditary ATIII deficiency, cases of recurrent thrombosis were reported in patients with hereditary HCII deficiency. Here, plasma HCII activity was studied in 372 patients with a history of thrombosis, classified according to their anticoagulant therapy. The mean plasma HCII level was significantly higher in patients with acute deep vein thrombosis (DVT) under heparin therapy than in patients with a history of thrombosis, who were studied more than 3 months after the acute event, and were either on, or had been on, oral anticoagulant therapy. HCII and fibrinogen were significantly correlated in all three groups of patients. These results were strengthened by those of a follow-up study in 23 patients with acute DVT. Changes in plasma HCII activity paralleled those of fibrinogen. This suggests that HCII might behave like an acute phase reactant in patients with thrombosis and that the measurement of its plasma level as a risk factor for thrombosis should be performed some time after the acute episode. In conclusion, the prevalence of HCII deficiency in patients with a history of thrombosis might have been underestimated in series which included patients with acute thrombosis.  相似文献   
963.
Conditions that affect the dentition and the materials utilized to treat these conditions are often unfamiliar to the physician. Dental caries and missing teeth are processes routinely treated in dental practice. Recent improvements in dental materials and techniques permit the dentist to restore the dentition to allow for corrected form, function, esthetics, and patient comfort. This paper describes some of the common conditions that affect the dentition, and the modalities routinely used to treat them.  相似文献   
964.
Malignant fibrous histiocytoma is a neoplasm that can occur both in soft tissue and bone but it is preponderantly found in soft tissue of the extremities. The majority of cases occur in late adult life; and, males are affected more often than females. Most of the patients come to see the doctors because of a mass in various regions and pain. The prognosis is poor, patients usually die from metastasis of the neoplasm to important organ. According to some reports, the neoplasm can occur in oral soft tissue and jaw, thus, dentists should know about important features of the neoplasm in order to be able to diagnose it from other benign oral lesions and can treat correctly.  相似文献   
965.
The aim of the study was to determine, in a group of patients with therapy-resistant burning mouth syndrome (BMS), the possible deficiency of vitamins B1, B2, and B6 and the effect of proper vitamin replacement therapy. Sixteen individuals, aged 47 to 81 years, participated in the study. All underwent a base-line examination comprising anamnestic information, subjective assessment of symptoms, dietary registration, salivary analysis, and serum analysis of thiamine (B1), riboflavine (B2), and pyridoxine (B6). Fifteen individuals had low thiamine and/or riboflavine levels in accordance with suggested levels in the literature and were given replacement therapy. No effect on BMS of vitamin replacement therapy or placebo therapy could be demonstrated.  相似文献   
966.
Neisseria meningitidis group B (MenB) strains isolated from 1976 to 1987 in Finland in 339 patients with invasive infection were sero/subtyped by whole cell enzyme immunoassay using monoclonal antibodies to class 1 and 2/3 outer membrane proteins. 66.7% of the strains could be serotyped (class 2/3) and 70.2% subtyped (class 1). No single phenotype was clearly predominant. The most common serotypes were 4 (18.6%) and 14 (17.4%) and the most common subtypes P1.16 (20.1%) and P1.2 (12.1%). The Norwegian phenotype B:15:P1.16 was seen only rarely (a total of 18 strains). Strains from Northern Finland did not differ from those from Southern Finland: no single phenotype caused the slight increase seen in the incidence of MenB infections in the end of 1970s in the North.  相似文献   
967.
968.
Currently available approaches for the design of occupational case-control studies are reviewed. An accompanying paper reviews methods of analysis. We commence by drawing a distinction between cohort-based and registry-based studies. Methods for selecting cases and controls are then reviewed, including cumulative incidence and incidence density sampling, matching, sources of controls, and issues in control selection. Finally, the advantages and disadvantages of the case-control approach are summarized.  相似文献   
969.
In preventive medicine and occupational health, decision-makers face uncertainty, divergent opinions, and varying needs. In the Swiss aluminum industry, screening for industrial fluorosis illustrates how decision analysis and cost-effectiveness analysis can provide rational and explicit models of decision-making in such contexts. Data on fluoride-exposed potroom workers are used to compare the cost-effectiveness of two strategies: mass screening of fluorosis versus individual detection of the disease on the basis of the worker's symptoms. A decision-analysis and a sensitivity analysis are performed to assess the impact of the screening program for different levels of expected prevalence of the disease. The optimal decision, in economic terms, is the one that minimizes the pension and screening-related costs and maximizes the number of years of full working capacity. Swiss data suggest that a diagnosis of clinical fluorosis is unlikely before 10 years of exposure to fluoride. Between 10 and 30 years of exposure to fluoride, mass screening may be more cost-effective than individual detection of the disease, even when the expected prevalence of the disease in a given industrial setting is less than 10%.  相似文献   
970.
In clinical diagnosis, a patient's symptoms are observed and the probabilities of various diseases are assessed. A widely used method of formalizing this approach is independent Bayes in which symptoms are assumed to be independent conditional on the disease category. Correspondence analysis provides a method for examining the dependence between symptoms and assists in the selection of a reduced set of symptoms for the application of the independent Bayes method. This approach is illustrated on two data sets concerned with patients attending Accident and Emergency departments with chest pain and acute abdominal pain, respectively.  相似文献   
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