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排序方式: 共有454条查询结果,搜索用时 15 毫秒
101.
PL Mollison 《Transfusion》1989,29(4):347-354
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The absence of a vertebral pedicle, regardless of location, always merits careful consideration. There are a variety of disease states in addition to intrinsic mechanisms which may influence the development of the spine and hence potentiate pedicular absence. Each of these diseases or processes must be considered when confronted by a missing pedicle. This paper will identify and briefly discuss the most common conditions resulting in pedicular absence. 相似文献
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109.
A prospective evaluation of cryopreservation strategies in a two-embryo transfer programme 总被引:2,自引:10,他引:2
Horne G; Critchlow JD; Newman MC; Edozien L; Matson PL; Lieberman BA 《Human reproduction (Oxford, England)》1997,12(3):542-547
A total of 364 consecutive patients requesting in-vitro fertilization (IVF)
treatment were divided randomly into two groups. In the first group, two
embryos in the original IVF cycle were allowed to divide prior to transfer,
with any remaining embryos being cryopreserved at the pronucleate (PN)
stage. In the second group, all the embryos were allowed to divide to the
early cleavage (EC) stage, and the best two replaced; any suitable
remaining embryos were frozen at the 2- to 4- cell stage. A total of 134
cycles (36.8%) fulfilled the study criteria for a fresh embryo replacement
and supernumerary embryos cryopreserved. In the PN group, 72 out of 182
(39.6%) patients had a fresh embryo replacement accompanied by embryo
cryopreservation, which was not significantly different from the EC group
(62/182; 34.1%). The livebirth rate per fresh embryo transfer in the EC
group (17/62; 27.4%) was significantly higher than that for the PN group
(8/72; 11.1%; P < 0.05). Embryo survival following thawing was similar
for the PN (96/129; 74.4%) and EC (79/102; 77.4%) stages. Although not
significant, the livebirth rate following the transfer of thawed embryos
was higher in the PN group (11/44; 25.0%) than in the EC group (4/38;
10.5%). Following one fresh and two freeze-thaw embryo replacements, the
observed cumulative viable pregnancy rates were comparable for patients in
both the PN (40.2%) and EC (41.1%) groups.
相似文献
110.
PL Khong MT Chau ST Fan LLY Leong 《Journal of Medical Imaging and Radiation Oncology》1999,43(2):156-159
In a phase IIIb clinical trial of the ultrasound contrast agent Levovist® (Schering AG, Berlin, Germany), the role of Levovist® in the management of patients with clinically suspected hepatocellular carcinoma (HCC) was evaluated and its efficacy was assessed. The assessment included the duration of diagnostically usable Doppler signal enhancement, and safety and tolerance of intravenous administration. All patients with clinically suspected hepatocellular carcinoma were referred for Doppler sonographic examination over a 5-month period and lesions with absent or suboptimal Doppler signals were included in the trial. A total of 300 mg/mL in concentration (8.5 mL) of Levovist® was administered through a peripheral vein while Doppler signal intensity in the lesion, based on a visual score, was recorded. Blood pressure and pulse were recorded before and after injection. Thirty-eight patients were examined, of which 29 were included in the trial. The lesions were subsequently proven histologically to be 19 HCC, one cholangiocarcinoma, two regeneration nodules and one colonic metastasis. For six patients in whom histological proof was not available, the diagnosis of HCC was suggested based on markedly elevated serum alpha-fetoprotein levels. All but one (96%) of the 25 HCC demonstrated increased Doppler signal after Levovist®. There were no Doppler signals before and after Levovist® injection in three non-HCC lesions (two regeneration nodules and one colonic metastasis). Two patients (6.9%) suffered minor adverse reactions of nausea and vomiting. The results show that Levovist® is safe and is able to improve lesion characterization and increase diagnostic confidence of hepatocellular carcinoma by enhancing tumour vascularization Doppler signal intensity. 相似文献