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1.
Psychiatric Quarterly - 相似文献
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S P Newman G Woodman F Morén S W Clarke 《British journal of diseases of the chest》1988,82(3):262-267
Metered dose inhalers are sometimes used in conjunction with NebuhalerR, a 750 ml holding chamber, but the permissible delay time between actuating the aerosol into Nebuhaler and commencing inhalation is unknown. We have compared in 10 asthmatic patients the bronchodilator responses following inhalations of terbutaline sulphate from Nebuhaler after delays of 1, 5 and 30 seconds and following placebo inhalation. Terbutaline sulphate was administered as 2 puffs, each of 250 micrograms, separated by approximately 15 minutes. After each delay time, terbutaline produced increases in forced expiratory volume in one second (FEV1), peak expiratory flow rate (PEFR) and maximum expiratory flow following exhalation of 75% of the forced vital capacity (V max25) significantly greater than those after placebo (P less than 0.01). Changes in PEFR did not vary significantly among the three delay times, but the increases in FEV1 and in V max25 were significantly reduced with 30 seconds' delay. It is concluded that the delay between actuation into Nebuhaler and commencing inhalation can be extended from 1 second to 5 seconds without significant loss of drug efficacy, and that further extension to 30 seconds causes only a small loss of bronchodilatation: hence the delay time is unlikely to be of major importance in clinical practice. 相似文献
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J E Bright A C Woodman T C Marrs S G Wood 《Xenobiotica; the fate of foreign compounds in biological systems》1987,17(1):79-83
A methaemoglobin former, 4-aminopropiophenone (p-aminopropiophenone, PAPP), which is active only after metabolic activation in vivo, exhibits a sex difference in male Beagle dogs and bitches. Bitches produced more methaemoglobin for a given dose of PAPP than male dogs. The probable reason for this difference was a lower rate of N-hydroxylation in male dogs. 相似文献
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Psychiatric Quarterly - 相似文献
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Silber SJ; Nagy Z; Devroey P; Tournaye H; Van Steirteghem AC 《Human reproduction (Oxford, England)》1997,12(11):2422-2428
The aim of the study was to determine whether a prior diagnostic testicle
biopsy can predict success or failure of testicular sperm extraction (TESE)
with intracytoplasmic sperm injection (ICSI) in patients with
non-obstructive azoospermia caused by testicular failure, and what is the
minimum threshold of sperm production in the testis which must be surpassed
for spermatozoa to reach the ejaculate. Forty- five patients with
non-obstructive azoospermia caused by testicular failure underwent
diagnostic testicle biopsy prior to a planned future TESE-ICSI procedure.
The diagnostic testicle biopsy was analysed quantitatively, and correlated
with the quantitative findings of spermatogenesis in patients with normal
spermatogenesis, as well as with the results of subsequent attempts at
TESE-ICSI. Men with non- obstructive azoospermia caused by germinal failure
had a mean of 0-6 mature spermatids/seminiferous tubule seen on a
diagnostic testicle biopsy, compared to 17-35 mature spermatids/tubule in
men with normal spermatogenesis and obstructive azoospermia. These findings
were the same for all types of testicular failure whether Sertoli cell
only, maturation arrest, cryptorchidism, or post-chemotherapy azoospermia.
Twenty-two of 26 men with mature spermatids found in the prior testis
biopsy had successful retrieval of spermatozoa for ICSI, 12 of their
partners became pregnant, and are either ongoing or delivered. The study
suggests that 4-6 mature spermatids/tubule must be present in the testis
biopsy for any spermatozoa to reach the ejaculate. More than half of
azoospermic patients with germinal failure have minute foci of
spermatogenesis which are insufficient to produce spermatozoa in the
ejaculate. Prior diagnostic testicle biopsy analysed quantitatively (for
the presence of mature spermatids) can predict subsequent success or
failure with TESE-ICSI. Incomplete testicular failure may involve a sparse
multi-focal distribution of spermatogenesis throughout the entire testicle,
rather than a regional distribution. Therefore, it is possible that massive
testicular sampling from many different regions of the testes may not be
necessary for successful TESE-ICSI.
相似文献
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β-Lactoglobulin was isolated from infant formulae that were ultra high temperature (UHT) -treated, sterilized or spray-dried. The effect of the isolated β-lactoglobulin on SfaII-fimbriae-mediated adhesion of Escherichia coli to human ileostomy glycoproteins was studied in vitro. β-Lactoglobulin isolated from sterilized formulae was found to perform significantly less well than preparations from spray-dried formulae (p = 0:05). Great heterogeneity was observed in the adhesion inhibitory capacity of β-lactoglobulin isolated from UHT-treated formulae. Therefore, no significant difference was observed between UHT-treated and sterilized formulae or spray-dried formulae (p < 0:10). It can be hypothesized that β-lactoglobulin from spray-dried and some UHT-treated infant formulae may affect the colonization of mucous membranes by E. coli strains causing neonatal septicaemia and meningitis. 相似文献