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91.
It is possible to stabilize foot-and-mouth disease antiserum by either freeze-drying in bottles or air-drying on paper for periods of 7 months.  相似文献   
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Results of the use of ampicillin, penicillin G and symptomatic therapy in the treatment of acute otitis media in 142 children were compared. Antibiotic therapy conveyed significant benefit. No major differences were observed between penicillin and ampicillin, except in the age group under 3 years where ampicillin was associated with the best results. Ampicillin appears to be the drug of choice. Its superiority over symptomatic therapy was statistically significant. Long-term sequelae were not observed in any of the three treatment groups. The relative merits of erythromycin and ampicillin require further study.  相似文献   
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The cystine-containing peptides of horse growth hormone were isolated and their amino acid sequences determined. Four unique half-cystine residues occur in two peptides, one containing 11 and the other, at the C-terminus of the protein, 15 amino acids. These sequences are compared with published data on growth hormones from other species.  相似文献   
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A significantly higher proportion of female hamsters developed tumors than did males given the same dose of adenovirus-12 (Huie) at birth over a dose range from 10(5.0) to 10(7.0)tcd(50) for human embryonic kidney cells. The 50% tumor dose (td(50)) was calculated to be 10(5.90)tcd(50) for females and 10(6.27) for males. Tumor response patterns induced with approximate td(50) inocula, 10(6.0) for females and 10(6.3) for males, were quite similar. The greater susceptibility of females was not found to be characteristic of a single strain of hamsters; nor was it attributable to a single lot of virus, to a single type of human cell used to produce the virus, nor to the degree of purification of the virus inoculum. The inoculation route did not appear to be of importance. Inasmuch as the foregoing extrinsic factors were of little influence, it was concluded that the mechanism is host-mediated, presumably hormonally controlled. The possibility that female cells, independent of host control, are more susceptible to adenovirus-12 oncogenesis than male cells has not been explored. Tumor regression occurred in 20% of the 211 tumors in males and in 15% of the 355 tumors in females. Adenovirus-12 T-antibody was detected in all but six of 473 sera tested from tumor-bearing hamsters and in 50% of 94 sera tested from non-tumor-bearing animals given virus at birth. Antibodies in the latter group were detected almost exclusively by indirect immunofluorescence. This technique appears to be extremely sensitive for detection of low levels of adeno-12 T-antibodies. The implications of T-antibody in nontumor-bearing virus-injected hamsters are discussed. Sera from normal hamsters were free of T-antibody.  相似文献   
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Sites of synthesis of plasma proteins in the foetal rat   总被引:4,自引:4,他引:0       下载免费PDF全文
1. The foetal rat of 16 or more days incorporates 14C-labelled amino acids into all the demonstrable plasma protein fractions in vivo. 2. Slices of foetal rat liver incubated in vitro incorporate 14C-labelled amino acids into the main plasma protein fractions, including the foetal-specific `post-albumin'. 3. Slices of placenta are unable to incorporate 14C-labelled amino acids into plasma proteins in vitro. 4. Liver slices from maternal rats incubated in vitro incorporate 14C-labelled amino acids into plasma proteins. The presence of post-albumin cannot be demonstrated after incubation. 5. Liver slices from foetal rats, but not from adult rats, contain demonstrable amounts of haemoglobin into which 14C-labelled amino acids are incorporated.  相似文献   
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