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991.

Background

To control avian coccidiosis with drug-independent strategy effectively and safely, multivalent hyperimmune egg yolk immunoglobulin (IgY) was prepared and its ability to protect against Eimeria tenella infection was evaluated.

Methods

Hens were orally immunized with live oocysts of 5 species of Eimeria for six times, antibody titers in serum and yolk were monitored by indirect enzyme-linked immunosorbent assay. The specific IgY was isolated, purified and lyophilized. IgY powder was orally administrated as dietary supplement in newly hatched chicks at various dosages. Birds were orally challenged with 10000 sporulated oocysts of E. tenella at 10 days of age, weighed and killed at 8 days post challenge, and the protective effect was assessed.

Results

The averge yeid of IgY was 9.2 mg/ml yolk, the antibody titer of IgY reached to 1:163840 per mg with the purity up to 98%. Chickens fed IgY resulted in reduced mortality, increased body weight gain (BWG), reduced oocyst shedding, reduced caecal lesion score and increased anti-coccidial index. In terms of BWG and caecal lesion, IgY significantly enhanced the resistance of bird at ≥ 0.05% of IgY in the diet when compared with the challenged control group (P<0.05). No significant difference was observed at dosage ≥ 0.5% and 1.0% when BWG and caecal lesion were compared with the sodium salinomycin control group, respectively (P>0.05).

Conclusion

Supplementing newly hatched chicks with Eimeria-specific IgY represents a promising strategy to prevent avian coccidiosis.  相似文献   
992.
The safety of hydroquinone   总被引:2,自引:0,他引:2  
Hydroquinone is one of the most effective molecules for the treatment of hyperpigmentary disorders, with over 40 years of efficacy and safety data. Concerns over its safety have been raised because of the fact that it is a derivative of benzene and because of the long-term side-effects observed with cosmetic products containing high concentrations of hydroquinone. However, despite 40-50 years use of hydroquinone for medical conditions, there has not been a single documented case of either a cutaneous or internal malignancy associated with this drug. This article reviews the evidence for the safety of hydroquinone in the treatment of hyperpigmentation conditions.  相似文献   
993.

Background

Patients with ectopic pregnancy (EP) and low serum hCG concentrations and women with a pregnancy of unknown location (PUL) and plateauing serum hCG levels are commonly treated with systemic methotrexate (MTX). However, there is no evidence that treatment in these particular subgroups of women is necessary as many of these early EPs may resolve spontaneously. The aim of this study is whether expectant management in women with EP or PUL and with low but plateauing serum hCG concentrations is an alternative to MTX treatment in terms of treatment success, future pregnancy, health related quality of life and costs.

Methods/Design

A multicentre randomised controlled trial in The Netherlands. Hemodynamically stable patients with an EP visible on transvaginal ultrasound and a plateauing serum hCG concentration < 1,500 IU/L or with a persisting PUL with plateauing serum hCG concentrations < 2,000 IU/L are eligible for the trial. Patients with a viable EP, signs of tubal rupture/abdominal bleeding, or a contra-indication for MTX will not be included. Expectant management is compared with systemic MTX in a single dose intramuscular regimen (1 mg/kg) in an outpatient setting. Serum hCG levels are monitored weekly; in case of inadequately declining, systemic MTX is installed or continued. In case of hemodynamic instability and/or signs of tubal rupture, surgery is performed. The primary outcome measure is an uneventful decline of serum hCG to an undetectable level by the initial intervention. Secondary outcomes are (re)interventions (additional systemic MTX injections and/or surgery), treatment complications, health related quality of life, financial costs, and future fertility. Analysis is performed according to the intention to treat principle. Quality of life is assessed by questionnaires before and at three time points after randomisation. Costs are expressed as direct costs with data on costs and used resources in the participating centres. Fertility is assessed by questionnaires after 6, 12, 18 and 24 months. Patients' preferences will be assessed using a discrete choice experiment.

Discussion

This trial will provide guidance on the present management dilemmas in women with EPs and PULs with low and plateauing serum hCG concentrations.

Trial registration

Current Controlled Trials ISRCTN 48210491  相似文献   
994.
Parasitic worms of the genus Schistosoma excrete relatively large amounts of immunogenic glycoproteins (circulating cathodic antigen [CCA]) that contain polysaccharide side chains with the trisaccharide Lewis-x (L(ex)) as a repeating unit. These carbohydrates evoke high titers of specific IgM antibodies that cross-react with the repeating L(ex) units on the surface of granulocytes. Consequently this might lead, in the presence of complement, to lysis of the granulocytes. In the present study, this hypothesis was investigated using anti-CCA mouse monoclonal antibodies (MoAbs) and polyclonal antibodies purified from sera of infected humans. By flow cytometry, it was demonstrated that the mouse MoAbs directed against CCA strongly recognized the granulocytes. It could also be shown that these MoAbs, as well as anti- CCA IgM antibodies purified from infected human sera, caused lysis of granulocytes in a complement-dependent cytotoxicity assay. Sera from healthy controls or from patients with other helminth infections resulted in negligible granulocytotoxicity. These in vitro observed phenomena may explain the mild to moderate neutropenia that occurs in schistosomiasis patients.  相似文献   
995.
Regurgitation in infants is a common problem. Recent issues, such as the increased risk of sudden infant death in the prone sleeping position, the finding of persisting occult gastro-oesophageal reflux with feed thickeners, and the increasing awareness of the cost-benefit ratio of medications may challenge the currently recommended management approach. A round table was organized to elaborate on the impact of (i) the pro supine sleeping campaigns in relation to sudden infant death and (ii) advancement in medical treatment on therapeutic strategies in regurgitating infants. The participants were opinion leaders from Europe and North America (Belgium, Canada, France, UK, Italy, Switzerland and The Netherlands). The importance of parental reassurance is stressed. As a consequence of the supine sleeping campaigns aiming to decrease the incidence of sudden infant death syndrome, the "prone elevated sleeping position" is no longer advised as a first-line therapeutic approach, although it is still recommended in "complicated reflux". It is emphasized that milk thickeners are an adequate therapeutic tool for regurgitation, but not in reflux disease. According to the literature, the efficacy of (alginate-) antacids, although very popular in some countries, is questionable. These recommendations will be of interest to first-line paediatricians, since about 40% of their patients, according to the literature, present because of regurgitation.  相似文献   
996.
Background: In the twelve months following the announcement of the UK pit closure programme in October 1992, 22 500 miners were made redundant. In 1994 we undertook a cross-sectional survey to determine whether the mental and physical health of men who had been employed in the Nottinghamshire mining industry differed from that of the general population.Methods: A postal questionnaire was designed incorporating the General Health Questionnaire (GHQ-12), and six domains from SF-36. Questionnaires were sent to 1064 miners and ex-miners and 2097 other men in Nottinghamshire. Non-responders were sent two reminders.Results: The final response rate was 51%. The percentage of responders with GHQ-12 scores of three or more (suggesting psychological disorder) was 46% for those still employed in the mining industry, 52% for unemployed former miners and 22% for working non-miners (odds ratios: 3.0 [95% C.I. 2.2–4.1] for current miners and 3.9 [95% C.I. 2.6–5.7] for unemployed miners compared with working non-miners). The miners and ex-miners also had lower scores (suggesting greater morbidity) for each of the SF-36 domains tested. When stratifying for age in respondents of social classes IIIM-V the scores of current miners were significantly lower than those of working non-miners (P < 0.01).Conclusions: This study suggests that when surveyed in 1994, men who had been employed in three Nottinghamshire collieries in 1992 were psychologically and physically disadvantaged compared with working non-miners. Whether these findings are a result of pit closures is uncertain. However, significant potential health needs have been demonstrated.  相似文献   
997.
Pelvic abscesses: transvaginal US-guided drainage with the trocar method   总被引:1,自引:0,他引:1  
McGahan  JP; Brown  B; Jones  CD; Stein  M 《Radiology》1996,200(2):579
  相似文献   
998.
999.
Thickness-equalization processing for mammographic images   总被引:2,自引:0,他引:2  
Byng  JW; Critten  JP; Yaffe  MJ 《Radiology》1997,203(2):564
  相似文献   
1000.
Summary— Normal intraocular pressure (IOP) is the result of an equilibrium between aqueous humor (AH) production, AH outflow and episcleral venous pressure. Most available antiglaucoma agents produce their effects by interacting with autonomic mechanisms (beta-blockers, epinephrin or parasympathomimetics). In contrast, the role of the central nervous system (brain and nerves) in the regulation of IOP remains unclear in view of the complex haemodynamic, metabolic or hormonal changes which occur under experimental conditions. In this paper, we discuss a basic understanding of the anatomic and physiological relationships between central nervous system and IOP and describe how the brain can affect functions in ciliary body and trabeculum meshwork.  相似文献   
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