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931.
The objective of this study was to determine if assisted hatching improved the rates of implantation, clinical pregnancy and ongoing pregnancy for in-vitro fertilization (IVF) patients aged > or =36 years. On the day of oocyte aspiration, consenting patients were randomized according to whether all embryos underwent the hatching procedure (hatched; n = 41) or all embryos remained unhatched (controls; n = 48). Patients in both groups were treated with methylprednisolone and doxycycline starting on the day of oocyte retrieval and continuing for 4 days. The hatching procedure was performed approximately 55 h after insemination on all potential embryos for transfer and employed the release of acidified acid Tyrode's medium against the zona pellucida to create an opening approximately 20 microm in diameter. No significant differences were noted in the mean age, number of oocytes aspirated and number of embryos transferred between the hatched and control groups. In addition, no significant differences were observed in the rates of implantation (11.1 versus 11.3%), clinical pregnancy (39.0 versus 41.7%) and ongoing pregnancy (29.3 versus 35.4%) between the hatched and control groups respectively. These results suggest that assisted hatching may have no significant impact on IVF success rates in the patient population studied.   相似文献   
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Toxic Shock Syndrome is an acute multisystemic disease, characterized by high fever, hypotension and involvment of the skin and mucous membrane, associated with multisystem dysfunction. It is a rare condition in the paediatric population. We describe a newborn child with asphyxia and meconium aspiration, who developed a temperature of ≥38.9°C, severe hypotension and rash with desquamation, associated with evidence of coagulopathy and renal and muscular dysfunction. Strict CDC criteria of toxic shock syndrome were fulfilled in our patient, with all major criteria verified. These criteria have never been validated in neonates, but in this case some symptoms favour a diagnosis of toxic shock syndrome since they are not associated with birth asphyxia, viral intrauterine infection or other disease. We believe a probable intrapartum transmission occurred through ingestion or aspiration of contaminated amniotic fluid. The patient described in this report is, to our knowledge, one of the youngest described to fulfil all of the strict CDC criteria for Toxic Shock Syndrome.  相似文献   
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Faguet  GB; Agee  JF 《Blood》1993,82(2):536-543
The common B-chronic lymphocytic leukemia (B-CLL) antigen (cCLLa) appears to be ideal for targeted immunotherapy in that it is the most prevalent and disease-restricted marker in B-CLL. To assess this potential, we developed four immunotoxins (ITs) of anti-cCLLa monoclonal antibody CLL2m (an IgG2a kappa), using ricin chain A (RTA) or its deglycosylated derivative (dgA), each conjugated to either the whole IgG molecule or its Fab' fragment. Each IT was tested in vitro for specificity and cytotoxic activity (assessed by protein synthesis inhibition [PSI] and by cell kill [CK] in the clonogenic assay) against B-CLL cells. RTA-based anti-CD5 ITs and enriched normal B and T lymphocytes were used as controls. Each IT exhibited antigen-specific, dose-dependent activity. Thus, whereas B-CLL cells exhibited dose- dependent PSI and CK (whether the B-CLL clone was CD5+ or CD5-), normal B (cCLLa-/CD5-) and T lymphocytes (cCLLa-/CD5+) remained unaffected. IT potency was independent of toxin glycosylation, but was slightly influenced by antibody valence; divalent ITs were twice as potent as monovalent ITs (IC50, 2.3 v 7.1 x 10(-11) mol/L; CK, 2.6- v 2.0-log reached with 524 v 1,072 IT molecules bound/cell, respectively). In the presence of ammonium chloride or Verapamil, IT-induced CK was enhanced 10- to 80-fold. These data suggest that the cCLLa is a promising target for IT-based immunotherapy of B-CLL in vivo and ex vivo.  相似文献   
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939.
对胡椒属(Piper Ruizet Pavon)植物中的木脂素类化合物精细立体结构与生物活性进行研究。选择该类化合物三种骨架的3个化合物进行了X衍射单晶结构分析,获得其立体结构参数;应用分子图形学,分子力学等诸方法,获得3种骨架中的9个分子的自由态下立体结构数据;并以已有的药理(血小板活化因子拮抗活性)实验数据为基础进行结构与活性分析。  相似文献   
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