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1.
[目的]用蛭孤菌促进大菱鲆的生长,提高存活率,消除养殖水体中的弧菌.[方法]采用20 d的换水周期,以不添加蛭弧菌的养殖池为对照组(B组),往水体中添加蛭弧菌的养殖池为蛭弧菌添加组(C组),以生产性的养殖池作为参照(A组),以成活率、增重率、体重平均日增长量、体长增长率、体长平均日增长量、肥满度为判断依据,确定蛭弧菌对大菱鲆生长的影响;对换水前后各组养殖水体中所含弧菌数进行检测.[结果]蛭弧菌添加组大菱鲆的生长指标和存活率显著高于生产组和对照组(P<0.05);与生产组相比,蛭弧菌添加组大菱鲆的成活率提高了13.23%,增重率、体重平均日增长量、体长增长率、体长平均日增长量、肥满度分别提高了663%、130.35mg、28.09%、31.82 μm、4.99.蛭弧菌添加组的弧菌数明显减少.[结论]蛭弧菌能够提高大菱鲆的成活率,促进其生长发育,并能有效控制养殖水体中弧菌数.  相似文献   

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In a controlled study, the protection effect of hepatitis B immune globulin (HBIG) was evaluated in patients hemodialyzed for less than one month in two collaborating units. Fifteen randomly selected patients received HBIG at five to eight week intervals throughout the study, and 13 other control patients received no immunoglobulin. During a follow-up period of 14 to 30 months, none of the HBIG-treated and 12 of the control patients developed evidence of exposure to virus B hepatitis, including 10 with HBs Ag antigenemia (p is less than 0.001): five of these remained persistently antigen positive. Evidence of non-B hepatitis was found in 8 HBIG-treated and in 3 non-treated patients. Only two HBIG-treated patients developed active antibodies against hepatitis B surface antigen. Thus, HBIG seems effective in preventing hepatitis B in hemodialysis patients, provided the interval between two injections is not greater than two months. However, prolonged administration of HBIG may impair passive-active immunization to hepatitis B virus.  相似文献   

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[目的]寻找食用菌黏菌病的有效化学防治方法.[方法]选取一些低毒、无污染的化学制剂.进行室内毒力试验,测定其对黏菌的抑制作用;通过室内生测结果选取对平菇菌丝生长影响较小的药剂进行菇棚内黏菌病防治试验.[结果]试验结果表明:绿丹苦参1 000倍液+水杨酸300倍液组合、克霉先锋1 000倍液、绿丹苦参1 000倍液、水杨酸300倍液效果较好,是生产实践中防治黏菌病应优先选用的药剂.[结论]研究结果为食用菌黏菌病的有效控制奠定了基础.  相似文献   

5.
We collected category fluency data from several moderate-to-large samples of participants at three different sites: the New York University Aging and Dementia Center, the Oregon Health Services Aging and Dementia Research Center, and the Einstein Aging Study at the Albert Einstein College of Medicine. These data were analyzed by calculating the average relative frequency (e.g., typicality) of the category members generated by each participant. Alzheimer's disease (AD) patients recalled fewer atypical members of common taxonomic categories than did the elderly control group. In addition, the probability of producing an item declined at a greater rate for AD patients than for the elderly control group over the duration of the task. According to sequential sampling models, this latter result implies that the rate at which AD patients search memory must be slower than the search rate of the elderly controls. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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OBJECTIVE: To review the epidemiology of group B Streptococcus (GBS) infection, risk factors for infection, and clinical manifestations of disease in the neonate, as well as the role of chemoprophylaxis and immunoprophylaxis in prevention of GBS disease and current recommendations for prevention. DATA SOURCES AND STUDY SELECTION: MEDLINE searchers (1976-1997) of the English-language literature. DATA SYNTHESIS: Despite clinical advances in health care in the past two decades, GBS remains a leading cause of serious neonatal infection. Most early-onset GBS infections can be prevented through the use of intrapartum antimicrobial chemoprophylaxis. Preventing GBS infection in neonates is more cost-effective than treating GBS infections, and implementing prevention programs can reduce morbidity and mortality resulting from GBS disease. Many proposals have been made regarding prevention strategies; however, they have not been implemented widely and consistently in the US. To coordinate both pediatric and obstetric supported strategies, the Centers for Disease Control and Prevention (CDC) recently published recommendations for prevention of neonatal GBS disease through two possible strategies. In the first strategy, intrapartum antibiotic chemoprophylaxis should be offered to all women identified by prenatal culture as colonized and those who develop premature membrane rupture or onset of labor at less than 37 weeks gestation. The second strategy involves administration of intrapartum antibiotics to all women who develop one or more risk factors at the time of membrane rupture or onset of labor. CONCLUSIONS: GBS is difficult to eradicate, causing many women to be colonized with the organism during pregnancy and labor, thereby infecting their infant. Prevention strategies have been published for more than 10 years without successful implementation. Although optimal prevention management has not been defined, following one of two strategies recommended by the CDC can prevent the majority of GBS infections in neonates.  相似文献   

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An area of unidirectional conduction block is one requirement for reentrant arrhythmias to occur. Functional block caused by dispersion of repolarization and refractoriness is the most probable mechanism of drug-induced unidirectional conduction block. We assessed the effects of lidocaine on spatial dispersion of myocardial repolarization and refractoriness in the intact porcine heart. Monophasic action potential duration at 90% repolarization, effective refractory period (ERP), and ventricular fibrillation cycle length (VFCL) were measured at two endocardial and one epicardial sites at baseline and during a treatment phase with D5W (n=11) or lidocaine 10 mg/kg/hour (n=12). Dispersion was calculated as the difference between the maximum and minimum values of the three recording sites. Lidocaine produced significant changes in ERP, VFCL, paced QRS duration, and intraventricular conduction time. It did not change basal levels of dispersion in repolarization and refractoriness. Lidocaine produced changes in myocardial electrophysiology that are uniform across the myocardium and thus did not change myocardial electrical heterogeneity. This may be a mechanism of the agent's lower proarrhythmic effects compared with other sodium channel blockers that increase myocardial electrical heterogeneity.  相似文献   

8.
Neonatal group B streptococcal infection is the primary cause of neonatal morbidity related to infection. It can often be prevented by identifying and treating pregnant women who carry group B streptococci or who are at highest risk of transmitting the bacteria to newborns. Increasing evidence and expert opinion support intrapartum treatment of women at relatively high risk of delivering an infant with group B streptococcal infection. Such women can be identified through the use of an anogenital culture for group B streptococci obtained at 35 to 37 weeks of gestation and by the presence of at least one of many risk factors associated with neonatal infection. These risk factors include preterm labor or rupture of the membranes at less than 37 weeks of gestation, previous delivery of an infant with invasive group B streptococcal disease, group B streptococcal bacteriuria during the present pregnancy, maternal intrapartum fever of 38 degrees C (100.4 degrees F) or higher and rupture of the fetal membranes for 18 hours or more. The recommended agent for intrapartum chemoprophylaxis is intravenous penicillin G; clindamycin is used in penicillin-allergic women. The use of risk markers alone to guide the administration of intrapartum antibiotics is much more cost-effective than other preventive strategies, but it exposes more women and infants to antibiotic-associated risks. Management of the infants of treated mothers is empiric and is currently guided by expert opinion.  相似文献   

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Previous studies have identified a number of different farm stressors and have reported gender and age differences in levels of stress. This study aimed to determine stress experienced by New Zealand dairy farmers, particularly in relation to adoption of new technology and its relationship to age and gender. Measures of farm stress and adoption of technology were completed by 985 dairy farmers. The highest levels of stress were reported for time pressures, machinery breakdown, weather, and government policies. Stress related to new technologies occurred rarely. Women reported more stress and higher levels of stress for understanding new technologies. There was also an increase in severity of stress with age related to new technologies. Overall, stress levels were moderate and may reflect favorable economic conditions. The findings suggest a need to tailor stress interventions to meet specific needs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Hepatitis B virus (HBV) accounted for 24% to 54% of the reported acute viral hepatitis cases in Singapore from 1982 to 1996. The prevalence of HBV infection, as indicated by the presence of markers of HBV, increased from 9.3% in children below 5 years of age to 54.6% in adults above 55 years. The overall hepatitis B surface antigen (HBsAg) prevalence was 5.7% for males and 3.4% for females, with the highest rate among the Chinese. About 39% of the HBsAg carriers were hepatitis B 'e' antigen positive. The main mode of transmission during the first year of life was perinatal, with 43% of the babies born to HBsAg-positive mothers developing the carrier state. Horizontal transmission within the infected household was significantly associated with sharing of personal and household articles. Based on the findings of seroprevalence surveys in various population groups and clinical trials on the safety, immunogenicity and efficacy of various doses and schedules with the plasma-based and yeast-derived hepatitis B vaccines in newborn babies, a national childhood hepatitis B vaccination programme was formulated and implemented in phases, starting with babies born to carrier mothers on 1 October 1985 and finally extending to all newborns on 1 September 1987. The hepatitis B prevention and control programme has been successful. During the period 1994 to 1996, more than 90% of children completed the full schedule of immunisation by below one year of age, and 85% had evidence of vaccination at school entry at age six. Follow-up of 2 cohorts of vaccinated children showed that perinatal transmission has been reduced by 80% to 100%. Horizontal transmission has also declined through other public health measures. The efficacy of the hepatitis B vaccine and the adequacy of reduced doses in the long-term protection of chronic carrier state have been shown in children and adults. The incidence of acute hepatitis B has declined from 10.4 per 100,000 in 1985 to 4.8 per 100,000 in 1996. There is a noticeable reduction in HBsAg prevalence in selected population (school children, national servicemen and antenatal women). The age-standardised incidence rate of primary liver cancer among males had also dropped from 27.8 per 100,000 per year during 1978 to 1982 to 19.0 per 100,000 per year during 1988 to 1992.  相似文献   

11.
This study evaluated the effects of a behaviorally oriented cardiac rehabilitation and secondary prevention program on lifestyle changes and on coronary recurrence rates. Patients recently treated with percutaneous coronary intervention (PCI) were randomized to an intervention with an aggressive focus on lifestyle changes (smoking, diet, exercise, and stress; n = 46) or to a standard-care control group (n = 42). Results showed that the intervention group had significantly larger overall lifestyle changes than the control group after 12, 24, 36, and 60 months. The intervention group had significantly lower rates of all coronary events (acute myocardial infarction, coronary artery bypass graft, PCI, cardiac death; 30.4% vs. 53.7%), and of cardiovascular mortality (2.2% vs. 14.6%). The need for future large-scale and long-term evaluations of lifestyle-oriented secondary prevention interventions of this kind is emphasized. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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