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991.
992.
Bulimia is a distinct diagnostic eating disorder with its most noted manifestation being the rapid ingestion of large quantities of food followed by its elimination through the mouth. Because of the dental implications of highly acidic stomach contents chronically being regurgitated, the dentist is in a unique position to help identify the patient with bulimia. Dental erosion is not only the most easily noted but also the most destructive of the many oral problems caused by bulimia. This report of case describes a preventive dental prosthesis that can be used by the patient with bulimia to protect those teeth that are most affected by dental erosion. The construction of the prosthesis is easily completed with materials in the dental office and provides a great service to the patient with bulimia.  相似文献   
993.
Sutureless bowel anastomosis using Nd:YAG laser   总被引:5,自引:0,他引:5  
Small bowel anastomoses were performed without sutures by using the Nd:YAG laser to produce welded enterotomies. Optimal energy levels for contact and noncontact laser were determined. Anastomoses produced using five target energy levels between 100 and 500 J were examined. Short-term anastomotic strength of these enterotomies was measured 1 min after the welding. Bursting pressure of the laser welded enterotomies was compared to the bursting pressure of traditional two-layer, inverting, interrupted sutured bowel anastomoses. The overall mean bursting pressure of non-contact-welded enterotomies was 50.6 mmHg. Optimal laser settings determined in this initial phase were then used to produce anastomoses in rabbits which are recovered postoperatively for 1 or 2 weeks in order to examine long-term viability and integrity of the anastomoses. All chronic rabbit preparations recovered without complication. The mean bursting pressure was 200 mmHg, not significantly different from that of uncut bowel or two-layer sutured anastomosis.  相似文献   
994.
995.
996.
Monandry (monogamy) in natural populations of anopheline mosquitoes   总被引:1,自引:0,他引:1  
Polymorphic Y chromosomes within two species of anopheline mosquitoes provide markers for testing if females are inseminated by one or more males in nature. Wild-caught females of Anopheles dirus (sp. A) and An. maculatus s.s. produced 291 and 55 families, respectively, which showed a single type of Y chromosome. One family of the former species showed two types of Y chromosomes. These field data support the idea, established from laboratory studies, that female mosquitoes are largely monandrous (monogamous). Such information is important in interpretation of population biological data and, practically, in attempts to control insect pests by use of genetically designed males.  相似文献   
997.
998.
About 85% of the population of two Somali communities harboured soil-transmitted intestinal nematodes and/or protozoa. The commonest parasite (75% in the Lafoole institution and 59% in the Afgoye institution) was Trichuris trichiura. Mixed infections were common. The source of infection is contaminated fields around dwelling quarters, because of indiscriminate defaecation. One of the factors responsible for the higher incidence of hookworm in Lafoole (45%) compared with Afgoye (1.5%) may be the different soil character of the surrounding fields.  相似文献   
999.
Immunological aspects of occupational lead exposure   总被引:3,自引:0,他引:3  
  相似文献   
1000.
Delta hepatitis virus infection in China   总被引:1,自引:0,他引:1  
To assess the prevalence, epidemiological features and prognostic implications of hepatitis D (Delta) in Sichuan Province, The People's Republic of China, 649 sera (515 from HBsAg positive patients and 134 from HBsAg negative subjects) were tested by radioimmunoassay (RIA) for antibody to the hepatitis D virus (anti-HD). Forty-seven sera (7.2%) showed some degree of reactivity. Serial dilutions of these sera indicated that prozoning was not responsible for the equivocal results. Thirty-four of the 47 sera were submitted under code to a second laboratory for independent analysis. According to those results anti-HD antibodies were detected in four of these sera. The overall prevalence of anti-HD in the HBsAg positive patients therefore was 0.8% (4/515). On the basis of clinical, biochemical and histological data 427 HBsAg positive sera were further divided into acute Type B hepatitis, chronic Type B hepatitis, healthy carrier state and hepatocellular carcinoma (HCC) subgroups. Two of 65 (3.1%) anti-HD positive sera belonged to the acute Type B hepatitis group; one of 104 (0.9%), the chronic Type B hepatitis group and one of 246 (0.4%), the healthy carrier group. No antibody was detected in sera from 12 HBsAg positive HCC patients. All HBsAg negative patients were negative for anti-HD antibody. The results of this study indicate that despite a high prevalence of hepatitis B virus infection, positive serology for delta virus is uncommon in Sichuan Province, The People's Republic of China.  相似文献   
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