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41.
In Egypt, reclaiming portions of the desert using water from the Nile has resulted in large-scale invasion of Biomphalaria alexandrina in these regions. Studies exploring the local adaptation of Schistosoma mansoni to its snail host have been carried out to predict the extension of schistosomiasis to newly reclaimed areas. A meta-analysis of the relevant reports was conducted to compare the different biological characteristics of sympatric and allopatric Schistosoma mansoni and Biomphalaria alexandrina using different experimental designs. The results showed that there were no significant differences in the biological characteristics of sympatric and allopatric populations. The experimental design of some of the studies analyzed was found to affect the total cercarial production. The distance between the origin of the parasite and that of the snail did not affect any of the biological characteristics. The results showed that there is no evidence of local adaptation between Schistosoma mansoni and Biomphalaria alexandrina; however, the parasite is adapted to its intermediate host throughout the water bodies located in Egypt. The absence of local adaptation between Schistosoma mansoni and Biomphalaria alexandrina is likely of critical importance in predicting public health risks engendered by future reclaimed agriculture projects. Indeed, these results could assist in determining the appropriate balance between the development of water resource projects and schistosomiasis control in Egypt.  相似文献   
42.

Introduction

The aim of the study was to detect the effect of laparoscopic greater curvature plication (LGCP) on peripheral blood lymphocyte subsets (helper and cytotoxic T lymphocytes – CD4+ and CD8+ T cells respectively), leptin level and weight loss in morbidly obese patients.

Material and methods

Morbidly obese patients (n = 20, age range: 25–50 years, body mass index (BMI) range: 37–45 kg/m2) who underwent LGCP were enrolled in a prospective study to determine the percentages of their peripheral blood T cells (CD4+ and CD8+) before and 4 months postoperatively using flow cytometry. Also, the level of their leptin before and 4 months postoperatively was established using enzyme-linked immunosorbent assay (ELISA). The data are expressed as the percentage of total lymphocytes ± the standard error of the mean.

Results

A decrease in the BMI and loss of weight (31.20 ±1.2%) were confirmed 4 months postoperatively since BMI was 44.71 ±4.3 (range: 37–45) kg/m2 preoperatively, and decreased to 31.80 ±1.1 (range: 24–33) kg/m2 after surgery. The mean percentage of CD4+ and CD8+ T lymphocytes significantly decreased postoperatively (38.2 ±1.5 before and 29.3 ±2.6 after operation for CD4+, 17.3 ±1.8 preoperatively and 9.5 ±1.7 postoperatively for CD8+, p < 0.05). The mean leptin level was 43.01 ±22.01 preoperatively while postoperatively it was 24.8 ±11.1 (p < 0.05), so the leptin level substantially decreased compared to its preoperative values.

Conclusions

This study found that weight loss after LGCP in morbidly obese patients led to decreases in levels of leptin and circulating immune cells compared to their preoperative values.  相似文献   
43.
44.

Background

Primary care is increasingly interested in the identification of frailty, as it selects the target population for integrated care. However, instruments for the identification of frailty specifically validated for use in primary care are scarce. This study developed the Easycare Two-step Older persons Screening (Easycare-TOS), which provides a valid, efficient, and pragmatic screening procedure to identify frail older people.

Aim

This paper aims to describe the development of the Easycare-TOS and the data from the pilot studies.

Design and setting

Observational pilot study in seven academic GP practices in and around Nijmegen, The Netherlands.

Method

The Easycare-TOS was developed in a cyclic process with the input of stakeholders. In every cycle, the requirements were first defined, then translated into a prototype that was tested in a pilot study. The Easycare-TOS makes optimal use of prior knowledge of the GP, and the professionals’ appraisal is decisive in the frailty decision, instead of a cut-off score. Further, it considers aspects of frailty, as well as aspects of the care context of the patient.

Results

The pilot data have shown that after step 1, two-thirds of the patients do not need further assessment, because they are judged as not frail, based on prior knowledge of the GP. The overall prevalence of frailty in this pilot study is 24%. Most professionals who participated in the pilot studies considered the time investment acceptable and the method to be of added value.

Conclusion

The Easycare-TOS instrument meets the predefined efficiency, flexibility, and acceptability requirements for use as an identification instrument for frailty in primary care.  相似文献   
45.
Our goals were to determine the prognostic value of a yolk sac or fetal heart motion seen during an early accurately dated transvaginal ultrasound (TVU). We reviewed 225 consecutive pregnancies for fetal heart motion data. Furthermore, 63 pregnancies following in-vitro fertilization were reviewed for yolk sac information. The TVU was performed between 5 and 6 weeks following presumed conception (heart motion data) and between 22 and 32 days following in-vitro fertilization (yolk sac data). Pregnancies were followed until an ongoing pregnancy or spontaneous abortion was documented. The presence of a yolk sac between 22 and 32 days from fertilization was associated with the development of fetal heart motion in 94% of cases. The absence of the yolk sac by 32 days after fertilization was always associated with a poor outcome. In women < 36 years of age, the presence of fetal heart motion was associated with a spontaneous abortion in only 4.5% of the cases. However, the incidence of spontaneous abortion following fetal heart motion increased to 10% in women 36-39 years and 29% in women > or = 40 years of age. The presence of heart motion should not be considered a reassuring sign in the older woman. These data have implications regarding early embryology and the counselling of infertility patients.   相似文献   
46.
Over a 26 month period 17% of couples having treatment in our clinical programmes selected a commercially available protein (normal serum albumin, NSA) prepared from pooled human sera instead of using their own serum as a supplement for their embryo culture media. In a retrospective analysis of >2000 gonadotrophin-stimulated cycles and 1000 cycles where frozen/thawed embryos were transferred, fertilization, embryo quality and pregnancy rates following in-vitro fertilization (IVF), gamete intra-Fallopian transfer (GIFT) or intracytoplasmic sperm injection (ICSI) were unaffected by the type of protein used to supplement the culture medium. When embryos were thawed in medium containing NSA, both pregnancy (PR) and implantation rates (IR) were significantly lower (P <0.05) than if the medium was supplemented with serum (PR 8.3% and 17.5%; IR 4.6% and 10.5%). Inclusion of NSA before freezing reduced the IR of thawed embryos. To further test this observation all cycles where embryos were cultured and frozen in medium containing NSA (173 cycles) were matched to cycles where serum was used and the outcome was compared. At the end of 1995 just over half of the embryos in both groups had been thawed. No statistical difference was noted in the pregnancy rates (NSA, 5.6% versus serum, 11.3%) but the IR per embryo was significantly lower when embryos were cultured and frozen in medium supplemented with NSA (2.2%) than when serum was used as the supplement (6.6%).   相似文献   
47.
48.
Sixty heavily lice-infested male and female children (4–15 years) were selected and subjected to the treatment with a neem seed extract shampoo. Twenty to thirty milliliter of the shampoo were thoroughly mixed with completely wet hair and rubbed in to reach the skin of the scalp. After 5, 10, 15 and 30 min, the shampoo was washed out and the hair basically combed. Head lice were collected and examined. The neem seed extract shampoo proved to be highly effective against all stages of head lice. No obvious differences regarding the efficacy of the shampoo were observed between an exposure time of 10, 15 or 30 min. No side effects, such as skin irritation, burning sensations, or red spots on the scalp, forehead or neck, respectively, were observed.  相似文献   
49.
Inflamed fibronectin: an altered fibronectin enhances neutrophil adhesion   总被引:4,自引:0,他引:4  
Vercellotti  GM; McCarthy  J; Furcht  LT; Jacob  HS; Moldow  CF 《Blood》1983,62(5):1063-1069
Recent investigations have emphasized the role of activated granulocytes in mediating vascular endothelial injury in the pathogenesis of shock lung. In vitro studies have indicated that tight adherence of the neutrophil to the endothelium is crucial for the development of cellular injury. Fibronectin is critical to cell-to- substratum and cell-to-cell interactions. Since fibronectin resides in plasma, on endothelial cell surfaces and is secreted into cell matrices, the adhesive properties of fibronectin must be modulated, lest universal cell agglomeration occur, yet be enhanced when cell attachment is appropriate. In these studies, treatment of fibronectin- coated surfaces with neutrophil release products increased the adhesion of activated neutrophils. Similarly, endothelial cells treated with neutrophil release products become a more adherent substrate for neutrophils. This enhanced adherence generated by treatment of fibronectin with neutrophil supernatants is inhibitable by heat and the lysosomal proteinase inhibitor, pepstatin-A. Neutrophil release products cause proteolytic fragmentation of fibronectin and enhanced fibronectin immunofluorescence on endothelial cells. In addition, neutrophils are more injurious to endothelial cells that have been pretreated with neutrophil release products. Neutrophils may enhance their own adherence to endothelial cells by altering fibronectin, and this altered, or "inflamed," fibronectin may serve as an amplifier of inflammation.  相似文献   
50.

Background  

Recent evidence, both animal and human, suggests that modifiable factors during fetal and infant development predispose for cardiovascular disease in adult life and that they may become possible future targets for prevention. One of these factors is maternal psychosocial stress, but so far, few prospective studies have been able to investigate the longer-term effects of stress in detail, i.e. effects in childhood. Therefore, our general aim is to study whether prenatal maternal psychosocial stress is associated with an adverse cardio-metabolic risk profile in the child at age five.  相似文献   
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