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排序方式: 共有594条查询结果,搜索用时 31 毫秒
101.
目的 用重组日本血吸虫22kD表膜蛋白(rSj22)免疫水牛,检测特异性IgG抗体的应答水平,并观察抗血吸虫的保护效果。方法 用抗原(rSj22)加佐剂(Quil-A)肌肉注射免疫水牛,以1000条日本血吸虫尾蚴攻击感染,感染后55d剖杀,计算减虫和减卵率,用免疫印斑和ELISA方法测定抗体反应。结果 免疫组每头牛血清均能特异地识别Quil-A对照组相比,减虫率仅8.5%肝卵EPG减少12.3%,粪卵EPG减少26.8%,但均无统计学意义,结论 用rSj22kD抗原免疫水牛诱导的特异性IgG抗体不能发挥免疫保护作用。 相似文献
102.
MJ Bennett GJ Duncombe 《The Australian & New Zealand journal of obstetrics & gynaecology》2001,41(2):191-194
In this article, we describe a relatively simple surgical option that we believe is indicated for use in cases of cervical incompetence. We discuss the advantages of this procedure to the surgeon and patient, and give details of 59 patients who have undergone this procedure one or more times over a 13-year period. A short review of the history of treatment of cervical incompetence and of recent trends for its management is also presented. 相似文献
103.
Continually maintaining maximally suppressive drug concentrations represents a key defence against the emergence of resistance. If drug levels fall and replication occurs, the opportunity for mutant virus to be selected occurs. It has been increasingly recognized that variability in the pharmacokinetics of antiretrovirals, particularly protease inhibitors (PIs), means that drug exposure is not always optimal, giving the virus a chance to replicate. A significant number of patients receiving PIs two or three times daily will have trough (Ctrough or Cmin) plasma concentrations, which are close to, or below, the plasma protein binding‐corrected inhibitory concentration (IC50 or IC95) during the dosing interval. It is primarily in this context that therapeutic drug monitoring of PIs has been proposed as an aid to patient management, to ensure that patients maintain adequate drug concentrations throughout the dosing interval. Ideally, an antiretroviral drug will have a pharmacokinetic (PK) profile that maintains drug levels well above the viral inhibitory concentration throughout the entire dosing interval. Beneficial drug–drug interactions have been shown to improve PI pharmacokinetics. Ritonavir (RTV) inhibits the key enzymes that limit the bioavailability or speed the metabolism of other PIs. It is therefore increasingly used for boosting and maintaining PI plasma concentrations. At low (100 mg twice a day) doses it acts as a pharmacoenhancer of indinavir (IDV), amprenavir, saquinavir, lopinavir and to a more limited degree nelfinavir. Using a pharmacoenhancer with a PI results in increased exposure to the PI, higher Cmin levels, and in most cases prolonged elimination half‐lives. The long‐term clinical benefits of PK enhancing are unknown as are the long‐term toxicities, although the incidence of nephrolithiasis with IDV appears increased when IDV is combined with low‐dose RTV in HIV‐infected patients. Head‐to‐head clinical comparisons of boosted PI regimens will help answer some of the questions that remain with regard to PK enhancement. 相似文献
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106.
马蓝的化学成分研究 总被引:15,自引:0,他引:15
Seven compounds have been isolated from the whole plant of Strobilanthes cusia (Nees) O. Ktze. Three of them are triterpenes (Ⅰ~Ⅲ), two are indole alkaloids (Ⅳ, Ⅴ), two are quinazolinone alkaloids (Ⅵ, Ⅶ). On the basis of spectral analysis and physicochemical properties, their structures were established as lupeol (Ⅰ), betulin (Ⅱ), lupenone (Ⅲ), indigo (Ⅳ), indirubin (Ⅴ), 4 (3H)-quinazolinone (Ⅵ), 2, 4 (1H, 3H)-quinazolinedione (Ⅶ). Ⅵ and Ⅶ were found from natural plant for the first time.The results of the pharmacological tests demonstrate that compound Ⅴ has anticancer activity and compound Ⅵ has hypotensive action. Compound Ⅶ can be quantitatively determined by HPLC, which may serve as a quality control standard for materia medica and its preparations. Compounds Ⅵ and Ⅶ have been confirmed by means of synthesis. 相似文献
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OBJECTIVE: To study the relation between traumatic birth and the development of permanent facial palsy in the newborn. DESIGN: Retrospective case control study of children with 'congenital' facial palsy. SETTING: Two tertiary referral centres for patients with facial palsy. SUBJECTS: 61 children with established facial palsy. MAIN OUTCOME MEASURES: Odds ratios of recognised factors for birth injury: maternal primiparity, high birth weight, and the use of obstetric forceps at delivery. RESULTS: 13.2% of those studied had forceps assisted delivery compared to 10.2% in the normal population (odds ratio 1.34; 95% confidence intervals 0.61 to 2.97) 39.6% were born to primiparae compared to a national rate of 36.7% (1.13; 0.65 to 1.96) and only 18.9% weighed more than 3500 g at birth (0.37; 0.19 to 0.74). CONCLUSIONS: There is no association between the development of permanent 'congenital' facial palsy and recognised risk factors for birth injury. These data suggest an intrauterine rather than a traumatic aetiology. 相似文献
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110.
DESIGN: A case of Nance-Horan syndrome in a male is presented, with some features of the condition in his carrier mother and her mother. It is proposed that Nance-Horan syndrome might be a contiguous gene syndrome mapping to chromosome Xp21.2–p22.3.
SETTING: The proband had congenital cataract micro-phthalmia and dental abnormalities including screwdriver shaped incisors and evidence of enamet pitting hypoplasia. The region Xp2I.2–p22.3 also contains the tooth enamet protein gene, ametogenin (AMGX).
RESULTS: Using molecular genetic techniques, we have shown that there is no evidence that the AMGX gene is deteted in this case of the Nance-Horan syndrome. 相似文献
SETTING: The proband had congenital cataract micro-phthalmia and dental abnormalities including screwdriver shaped incisors and evidence of enamet pitting hypoplasia. The region Xp2I.2–p22.3 also contains the tooth enamet protein gene, ametogenin (AMGX).
RESULTS: Using molecular genetic techniques, we have shown that there is no evidence that the AMGX gene is deteted in this case of the Nance-Horan syndrome. 相似文献