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91.
In-vitro fertilization patients (n = 15) at risk of ovarian hyperstimulation syndrome (OHSS) (oestradiol > or =4500 pg/ml on the day of human chorionic gonadotrophin administration and 25 or more follicles of intermediate or large size) underwent aspiration of all follicles and cryopreservation of all fertilized oocytes at the pronuclear stage. Patients were monitored for up to 2 weeks post- retrieval. Subsequent transfer of cryopreserved-thawed embryos was performed in programmed cycles using exogenous oestrogen and progesterone for endometrial preparation. Two patients (13%) developed OHSS necessitating hospitalization and vaginal aspiration of ascitic fluid. Two other patients (13%) developed moderate OHSS requiring ascitic fluid vaginal aspiration in the office setting, with dramatic improvement of the condition. Subsequent transfer of cryopreserved- thawed embryos yielded a clinical pregnancy rate of 58% per transfer and ongoing or delivery rates of 42 and 67% per transfer and per patient respectively. By eliminating pregnancy potential with cryopreservation of all prezygotes and examining the pregnancy potential with subsequent cryopreserved-thawed transfers, it is concluded that OHSS is reduced, but not eliminated for patients at risk. Subsequent transfer of cryopreserved-thawed prezygotes in a programmed cycle with exogenous steroids yields an excellent pregnancy rate.   相似文献   
92.
93.
Antibodies with Differing Molecular Sizes in Mice   总被引:1,自引:0,他引:1       下载免费PDF全文
The antibody responses of C3H mice to haemocyanin, pneumococcal polysaccharide (SSS III) and sheep erythrocytes were studied after a single intravenous administration. Serum antibody against each antigen was present on the fifth, but not on the third day.

Antibodies against haemocyanin and against SSS III migrated electrophoretically as γ globulins and had the ultracentrifugal sedimentation properties of 6.5S globulins. Sheep erythrocyte haemolysins were largely γ macroglobulins which sedimented in the ultracentrifuge in the manner of 18S globulins. A small proportion of haemolysin activity was found among the 6.5S γ globulins.

  相似文献   
94.
Macrophage recognition of Salmonella enterica serovar Typhimurium leads to a cascade of signaling events, including the activation of Src family and Syk kinases and the production of reactive oxygen species (ROS), which are critical for host innate defense during early stages of bacterial infection. ROS production depends on the NADPH oxidase, but little is known about the innate immune receptors and proximal adapters that regulate Salmonella-induced ROS. Herein, we demonstrate that serovar Typhimurium induces ROS through a pathway that requires both triggering receptor expressed on myeloid cells 2 (TREM2) and DAP12. This pathway is highly analogous to the pathways utilized by Fc receptors and integrins to regulate ROS production. Oral infection of mice with serovar Typhimurium demonstrates that the DAP12-dependent pathway regulates cecal colonization during early stages of Salmonella infection. Thus, DAP12 is an important regulator of Salmonella-induced ROS production in macrophages, and TREM2 is essential for linking DAP12 to the innate response to serovar Typhimurium.  相似文献   
95.
Observations from diverse studies on cell biomechanics and mechanobiology reveal that altered mechanical stimuli can induce significant changes in cytoskeletal organization, focal adhesion complexes, and overall mechanical properties. To investigate effects of short-term equibiaxial stretching on the transverse stiffness of and remodeling of focal adhesions in vascular smooth muscle cells, we developed a cell-stretching device that can be combined with both atomic force and confocal microscopy. Results demonstrate that cyclic 10%, but not 5%, equibiaxial stretching at 0.25 Hz significantly and rapidly alters both cell stiffness and focal adhesion associated paxillin and vinculin. Moreover, measured changes in stiffness and focal adhesion area from baseline values tend to correlate well over the durations of stretching studied. It is suggested that remodeling of focal adhesions plays a critical role in regulating cell stiffness by recruiting and anchoring actin filaments, and that cells rapidly remodel in an attempt to maintain a homeostatic biomechanical state when perturbed above a threshold value.  相似文献   
96.
Avian pathogenic Escherichia coli (APEC) are a substantial burden to the global poultry industry. APEC cause a syndromic poultry infection known as colibacillosis, which has been previously associated with broiler chickens over 2 weeks old. We recently reported that the intestinal tract of 1-day-old broilers harbours a rich reservoir of potentially pathogenic E. coli. Prior infections of the reproductive tract of breeders, egg hygiene and transportation all contribute to early colonization of the neonatal gut. Up to one-half of all flock deaths occur in the first week of production, but few data are available describing the contribution of E. coli. In the present study, all dead birds collected on the first daily welfare walk 48 and 72 h after chick placement underwent post-mortem examination. Diseased tissues were selectively cultured for E. coli and isolates subsequently virulotyped using 10 APEC virulence-associated genes (VAGs): astA, iss, irp2, iucD, papC, tsh, vat, cvi, sitA and ibeA. Approximately 70% of birds displayed signs of colibacillosis. Thirty distinct virulence profiles were identified among 157 E. coli. Isolates carried between zero and seven VAGs; ~30% of E. coli isolates carried five to seven VAGs, with 12.7% sharing the same VAG profile (astA, iss, irp2, iucD, tsh, cvi and sitA). Overall, this study demonstrates the significant contribution of E. coli infections to early broiler mortalities. The identification of a diverse E. coli population is unsurprising based on our previous findings. This work emphasizes the need for an effective vaccination programme and provides preliminary data for vaccine production.  相似文献   
97.

Objectives

To understand the vaginal bleeding/spotting experiences of postmenopausal (PM) women taking estrogen plus progestin therapies (EPT) and develop measures to assess these symptoms and their impact on women's daily lives in four countries.

Design

(1) Concept elicitation interviews were conducted with PM women in the US (n = 14), Italy (n = 15), Mexico (n = 15) and China (n = 15) to explore vaginal bleeding/spotting symptoms associated with EPT. The Post-Menopausal Bleeding Questionnaire (PMBQ) was also debriefed to evaluate understanding and comprehensiveness. (2) Based on concept elicitation, a single item electronic daily diary was developed and the PMBQ modified to form a 12-item impact measure. (3) The measures were pilot-tested and then cognitively debriefed with US women receiving EPT. All qualitative data was subject to thematic analysis.

Main outcome measures

The Vaginal Bleeding/Spotting Daily Diary, (VBS-DD) and Post-Menopausal Bleeding Impact Questionnaire (PMBIQ) were developed in this study.

Results

Concept elicitation identified vaginal bleeding and spotting as important symptoms for women taking EPT, impacting their emotional wellbeing, social life, ability to move freely, clothing and sexual activity. Based on pilot testing and cognitive debriefing, women demonstrated good understanding of the VBS-DD and the PMBQ was reduced to 10 items due to conceptual redundancy.

Conclusions

Women taking EPT in the US, China, Mexico and Italy reported vaginal bleeding/spotting symptoms that have a detrimental impact on their quality of life. Two new measures were developed to assess the severity and impact of vaginal bleeding/spotting specific to EPT. This work highlights the need for EPT-related symptoms to be a part of treatment decision-making.  相似文献   
98.
BACKGROUND: There is limited information about respiratory syncytial virus (RSV) in high-risk children from developing countries or on the genotype characterisation of the circulating virus. OBJECTIVE: To define the proportion of children with RSV associated lower respiratory tract infections (LRTI) that had risk factors for severe disease and to genotype the circulating RSV strains across the country. STUDY DESIGN: A prospective study was performed in four distinct regions. During April 2000-December 2000 (period 1), all children, with LRTI or without underlying high risk factors for severe RSV disease were enrolled. During January to September 2001 (period 2), only children with LRTI with underlying high risk factors were enrolled. Nasopharyngeal aspirates were evaluated for RSV infection using an ELISA test. RSV isolates were also subtyped and genotyped. RESULTS: Fifty three (24%) of 220 children enrolled during period 1 had risk factors for severe RSV disease; in addition to which a further 38 high-risk children were enrolled during 2001. RSV was isolated from 16 (30%) of 53 and 37 (22%) of 167 high-risk and non-high risk children, respectively, P=0.31. High-risk children were more likely to require intensive unit care (25 vs. 2.7%, P=0.02) and were also more likely to be hospitalised for a longer duration (median 7 vs. 5 days, P=0.06) than non high-risk infants. Overall (periods 1 and 2), RSV was isolated from 34 (37.4%) of the 91 high-risk infants enrolled. Among high-risk children, those from whom RSV was isolated were more likely to require hospitalisation (73.5 vs. 54.4%, P=0.07) and admission to an intensive care unit (14.7 vs. 1.8%, P=0.03) than those from whom RSV was not isolated. Of 40 isolates subtyped during period one, 92.5% were subtype A. Further, 27 (83.3%) of 30 subtype A isolates genotyped during period 1 clustered with GA2. CONCLUSION: RSV is an important cause of LRTI among high-risk infants in a developing country such as South Africa. For the season in question, the genotype that was dominant in Johannesburg was isolated throughout the country, suggesting that successful genotypes may have the ability to spread nationwide.  相似文献   
99.
Pulmonary sequestration   总被引:4,自引:0,他引:4  
Pulmonary sequestration refers to the situation whereby a portion of lung tissue receives its blood supply from an anomalous systemic artery. Three main variants exist: intralobar, extralobar and communicating bronchopulmonary foregut malformations. Venous drainage is typically via a systemic vein, although drainage into the pulmonary veins is well documented. Pulmonary sequestrations are the second commonest congenital lung anomaly. Affected individuals often have other anomalies which are responsible for most of the mortality associated with sequestrations. Diagnosis requires a high index of suspicion particularly in any child with a chest x-ray suggesting the presence of a mass, those with recurrent chest infections and those with other anomalies seen with the pulmonary sequestration spectrum. Surgical excision is usually advised, although embolisation of the feeding vessel has a role in selected cases.  相似文献   
100.
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