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71.
Ghaly M 《Bioethics》2012,26(3):117-127
When Muslims thought of establishing milk banks, religious reservations were raised. These reservations were based on the concept that women's milk creates 'milk kinship' believed to impede marriage in Islamic Law. This type of kinship is, however, a distinctive phenomenon of Arab tradition and relatively unknown in Western cultures. This article is a pioneer study which fathoms out the contemporary discussions of Muslim scholars on this issue. The main focus here is a religious guideline (fatwa) issued in 1983, referred to in this article as 'one text', by the Egyptian scholar Yūsuf al-Qaradāwī who saw no religious problem in establishing or using these banks. After a number of introductory remarks on the 'Western' phenomenon of milk banks and the 'Islamic' phenomenon of 'milk kinship', this article analyses the fatwa of al-Qaradāwī 'one text' and investigates the 'two contexts' in which this fatwa was discussed, namely, the context of the Muslim world and that of Muslim minorities living in the West. The first context led to rejecting the fatwa and refusing to introduce the milk banking system in the Muslim world. The second context led to accepting this system and thus allowing Muslims living in the West to donate and receive milk from these banks. Besides its relevance to specialists in the fields of Islamic studies, anthropology and medical ethics, this article will also be helpful to physicians and nurses who deal with patients of Islamic background.  相似文献   
72.
Knockout and pharmacological studies demonstrated that the activation of delta opioid peptide (DOP) receptors produces antidepressant-like effects in rodents. Here we report the results obtained with the novel DOP ligand H-Dmt-Tic-NH-CH2-Bid (UFP-502). UFP-502 bound with high affinity (pKi 9.43) to recombinant DOP receptors displaying moderate selectivity over MOP and KOP. In CHOhDOP [35S]GTPγS binding and mouse vas deferens experiments, UFP-502 behaved as a potent (pEC50 10.09 and 10.70, respectively) full agonist. In these preparations, naloxone, naltrindole and N,N(CH3)2Dmt-Tic-OH showed similar pA2 values against UFP-502 and DPDPE and the same rank order of potency. In vivo in mice, UFP-502 mimicked DPDPE actions, producing a significant reduction of immobility time after intracerebroventricular administration in the forced swimming test and a clear antinociceptive effect after intrathecal injection in the tail withdrawal assay. However, while the effects of DPDPE were fully prevented by naltrindole those evoked by UFP-502 were unaffected (tail withdrawal assay) or only partially reversed (forced swimming test). In conclusion, UFP-502 represents a novel and useful chemical template for the design of selective agonists for the DOP receptor.  相似文献   
73.
AIMS: Isolation and screening of extreme halophilic archaeon producing extracellular haloalkaliphilic protease and optimization of culture conditions for its maximum production. METHODS AND RESULTS: Halogeometricum sp. TSS101 was isolated from salt samples and screened for the secretion of protease on gelatin and casein plates containing 20% NaCl. The archaeon was grown aerobically in a 250 ml flask containing 50 ml of (w/v) NaCl 20%; MgCl(2) 1%; KCl 0.5%; trisodium citrate 0.3%; and peptone 1%; pH 7.2 at 40 degrees C on rotary shaker. The production of enzyme was investigated at various pH, temperatures, NaCl concentrations, metal ions and different carbon and nitrogen sources. The partially purified protease had activity in a broad pH range (7.0-10.0) with optimum activity at pH 10.0 and a temperature (60 degrees C). The enzyme was thermostable and retained 70% initial activity at 80 degrees C. Maximum protease production occurred at 40 degrees C in a medium containing 20% NaCl (w/v) and 1% skim milk powder after 84 h in shaking culture. Enzyme secretion was observed at a broad pH range of 7.0-10.0. Addition of CaCl(2) (200 mmol) to the culture medium enhanced the production of protease. Protein rich flours proved to be cheap and good alternative source for enzyme production. Different osmolytes were tested for the growth and production of haloalkaliphilc protease and found that betaine and glycerol enhanced growth without secretion of the protease. Immobilization studies showed that whole cells immobilized in 2% alginate beads were stable up to 10 batches and able to secrete the protease, which attained maximum production within 60 h under shaking conditions. CONCLUSIONS: Halogeometricum sp. TSS101 secreted an extracellular haloalkaliphilic and thermostable protease. The optimum conditions required for maximum production are 20% NaCl, 1% skim milk powder and temperature at 40 degrees C. Addition of CaCl(2) (200 mmol) enhanced the enzyme production. Immobilization of whole cells in absence of NaCl proved to be useful for continuous production of haloalkaliphilic protease. SIGNIFICANCE AND IMPACT OF THE STudy: The low cost protein rich flours were used as an alternative carbon and nitrogen sources for enzyme production. Immobilization of halophilic cells in alginate beads can be used in continuous production of halophilic enzyme. The halophilic and thermostable protease from Halogeometricum sp. TSS101 is good source for industrial applications and can be a suitable source for preparation of fish sauce.  相似文献   
74.
Polychlorinated biphenyl IUPAC# 101-PCB 101 (chlorination pattern-2,2',4',5,5') is a common, persistent non-coplanar PCB congener found in the ambient environment but information related to its metabolism in humans is lacking. Previous studies indicate PCB 101 is rapidly metabolized in mammals through CYP 2B and 3A family enzymes. Recently, PCB metabolism through a 2A family isoform in hamsters was also reported. To specifically identify the human CYP 450 isoforms responsible for PCB 101 metabolism, we compared human microsome metabolism to metabolism using several specific recombinant human CYP isoforms. These data characterized selective and extensive metabolism by human CYP 2A6. The product formed was the 4-hydroxy-PCB 101 metabolite (4-hydroxy-2,2',4',5,5') and was the only major metabolite observed in the recombinant and human microsome investigation. This is important information for predicting human specific toxicokinetics of PCBs.  相似文献   
75.
The complete DNA sequence of plasmid pHZ1358, a widely used vector for targeted gene disruption and replacement experiments in many Streptomyces hosts, has been determined. This has allowed a detailed analysis of the basis of its structural and segregational instability, compared to the high copy number plasmid pIJ101 of Streptomyces lividans 1326 from which it was derived. A 574-bp DNA region containing sti (strong incompatibility locus) was found to be a determinant for segregational instability in its original S. lividans 1326 host, while the structural instability was found to be related to the facile deletion of the entire Escherichia coli-derived part of pHZ1358, mediated by recombination between 36-bp direct repeats. A point mutation removing the BamHI site inside the rep gene encoding a replication protein (rep*) and/or a spontaneous deletion of the 694-bp region located between rep and sti including the uncharacterized ORF85 (orf85 ) produced little or no effect on stability. A pHZ1358 derivative (pJTU412, sti , rep*, orf85 ) was then constructed which additionally lacked one of the 36-bp direct repeats. pJTU412 was demonstrated to be structurally stable but segregationally unstable and, in contrast to sti + pHZ1358, allowed efficient targeted gene replacement in S. lividans 1326.  相似文献   
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禾谷镰刀菌Tri101基因编码的单端孢酶烯3-O-乙酰转移酶可通过加乙酰基的形式使禾谷镰刀菌产生的单族毒素(如DON)转变为较低的毒性。本研究利用RT-PCR技术从禾谷镰刀菌0623中扩增并克隆了Tri101基因的cDNA片段,测序结果表明,Tri101基因核苷酸序列阅读框架全长1356bp(GenBank序列号:GQ907236),编码451个氨基酸的多肽,推测分子量为49.45kD,等电点为5.14。氨基酸序列同源性比对结果表明,它与Kimura报道的禾谷镰刀菌Tri101氨基酸序列同源性最高,为99.56%,与其它13种镰刀菌的Tri101氨基酸序列的同源性分别为97.91%-75.68%。系统进化树分析结果表明,Fusarium graminearium0623与Fusarium sporotrichioides属于同一进化枝且与Fusarium asiaticum有较近的亲缘关系,而与F.oxysporum、F.moniliforme、F.nygamai、F.nisikadoi和F.decemcellulare的亲缘关系较远。  相似文献   
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80.
Increased Level of β-Amyloid in the Brain of Bulbectomized Mice   总被引:1,自引:0,他引:1  
Six weeks after bilateral olfactory bulbectomy, a peptide with molecular weight of 4 kD was revealed in extracts of the neocortex and hippocampus from mice. Using monoclonal antibodies 4G8, this peptide was identified as beta-amyloid. Its level was significantly higher in the bulbectomized animals than in sham-operated mice. The bulbectomized mice displayed sharp impairment in spatial memory when tested in the Morris water maze. The results suggest that bulbectomy initiates in the brain a pathological process similar to human Alzheimer's disease in location, biochemistry, and behavioral manifestations.  相似文献   
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