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81.
A new cytotoxic bastadin, bastadin 24 ( 1), and the previously reported bastadins 4, 5, 6, 7, 12, 13, and 21 ( 2- 8) were isolated from a polar extract of the Australian marine sponge Ianthella quadrangulata. The planar structure of bastadin 24 ( 1) was elucidated as the 25-hydroxy derivative of bastadin 6 ( 4) by employing spectroscopic techniques (NMR, MS, UV, and IR). All isolated bastadins were evaluated for their cytotoxicity toward a panel of 36 human tumor cell lines and were found to be moderately cytotoxic. Bastadin 24 ( 1) exhibited selective cytotoxic activity toward five of the 36 investigated tumor cell lines. Bastadins 7 ( 5) and 12 ( 6) significantly inhibited the serum + hEGF-induced (human epithelial growth factor) tubular formation of human umbilical vein endothelial cells (HUVEC) at a concentration of 1 mug/mL.  相似文献   
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Viscosin (1), an effective surface-active cyclic lipopeptide, was efficiently recovered from Pseudomonas libanensis M9-3 with a simple purification protocol. A major pigment also obtained during this process was identified as phenazine-1-carboxylic acid. The critical micelle concentration (cmc) of viscosin was determined to be 54 mg L (-1), and the minimum surface tension between air and water at the cmc was 28 mN m (-1). Viscosin forms stable emulsions even at low concentrations (7.5 mg L (-1)), and the conditional stability constant for a cadmium-viscosin complex was determined to be 5.87. The physicochemical properties measured for viscosin are similar to other well-studied biosurfactants such as rhamnolipid and surfactin. Viscosin inhibited migration of the metastatic prostate cancer cell line, PC-3M, without visible toxicity. These properties suggest the potential of viscosin in environmental and biomedical applications.  相似文献   
83.

Background

The aim of this retrospective study was to evaluate homologous intrauterine insemination (IUI) before in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI).

Patients and methods

A total of 448 patients were included. Data were collected from 1,086 treatment cycles.

Results

The live birth rate (BTH rate) was about 17% per couple. About 87% of all live births were achieved within the first three IUI cycles (P=0.05). A significantly better likelihood of pregnancy was found for patients with polycystic ovarian syndrome PCOS (P<0.05). Patients who were not tested for their tubal patency achieved a higher BTH rate compared to patients undergoing this investigation (P<0.05).

Conclusion

Using a minimally invasive method with easy handling and little psychological distress compared to IVF/ICSI, IUI should be a first step in infertility treatment. An evaluation of tubal patency beforehand seems indicated only if there is a specific patient history.  相似文献   
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Rhesus monkeys with experimental Plasmodium knowlesi infections of varying duration were treated with sodium sulfathiazole to sterilize the infection and after differing lengths of time were reinoculated intraperitoneally with homologous strains of the plasmodium, for the purpose of determining whether there is any acquired immunity to malaria in hosts from whom all parasites have been removed. Two monkeys, one receiving sulfathiazole on the 2nd day of acute infection and the other on the 4th day, had no immunity at the time of reinoculation, 3 weeks and 10 weeks later, respectively. Both developed infections which followed the course usual in an acute attack in a normal monkey. In monkeys which survived acute infection with the aid of immune serum or quinine and in which a naturally acquired immunity had developed to the point where the acute infection was converted into a chronic one, there was an undoubted persistence of partial immunity up to about a year after sterilization of the infection with sulfathiazole, as indicated by recovery of reinoculated animals after mild or moderately severe infections differing widely in characteristics from the infection in the normal monkey. The end point at which immunity disappears seems to be independent of the length of the chronic infection.  相似文献   
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