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排序方式: 共有1053条查询结果,搜索用时 15 毫秒
1.
Identifying alcoholism in medical patients 总被引:1,自引:0,他引:1
2.
Breast-feeding has numerous advantages, yet the trend to breast-feed is declining. Nurses, as well as patients, can benefit from increasing their knowledge base about breast-feeding. Nurses have an important role to play in supporting breast-feeding mothers with current research-based knowledge. More importantly, nurses also serve as patient advocates for the neonate. The use of appropriate nursing diagnoses may facilitate an optimal breast-feeding experience for our smallest consumer, the neonate. 相似文献
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5.
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
6.
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
7.
Influence of posture on hepatic perfusion and the presystemic biotransformation of propranolol: simulation of the food effect 总被引:2,自引:0,他引:2
Several research groups have reported that the oral administration of propranolol with protein-rich food leads to a marked increase (mean + 60%) in the area under the drug plasma concentration-time curve (AUC oral) of this highly metabolized and well-absorbed drug. It has been postulated that this "food effect" is caused at least in part by a transient increase in hepatic blood flow (QH) with its associated decrease in first-pass metabolism (hepatic extraction is a monotonic decreasing function of QH). A randomized crossover study using postural manipulations to produce changes in QH of the magnitude observed after food consumption (20% to 50%) was performed in an attempt to isolate the contribution of transient changes in QH to the food effect phenomenon. A solution of 80 mg propranolol HCl was taken orally and subjects were randomly assigned to postural manipulation protocols that should change QH such that AUC oral would be minimized (phase 1) or maximized (phase 2). Estimated QH (indocyanine green total body clearance from blood) was determined before and at three time points during each phase. It was observed that indocyanine green total body clearance during periods of standing was 15% to 40% below that observed during periods of seating (significant at p less than 0.05 for many of the appropriate comparisons). However, AUC oral for propranolol was not affected (mean +/- 1 SD; AUC phase 2/AUC phase 1+= 0.98 +/- 0.28) by these changes in QH, which are comparable to those encountered after food consumption.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
Hassett LC 《Anesthesia progress》1988,35(6):247-265
This bibliography contains both foreign (in brackets) and English language citations obtained from Index to Dental Literature, Index Medicus, and Psychological Abstracts for the period January 1986 to December 1987. Although a careful search of these indexes was performed, every relevant citation may not be included. Comments or suggestions regarding this bibliography are welcomed by the author. 相似文献
9.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献
10.
Van de Velde H; De Vos A; Joris H; Nagy ZP; Van Steirteghem AC 《Human reproduction (Oxford, England)》1998,13(11):3160-3164
In human in-vitro fertilization (IVF), the oocytes are surrounded by
cumulus and corona cells at the time of insemination so that their maturity
cannot easily be evaluated. The best IVF results are obtained if the
oocytes are inseminated 2-6 h after retrieval. In the intracytoplasmic
sperm injection (ICSI) procedure, the oocytes are denuded by enzymatic and
mechanical treatment in order to be able to perform the injection. As a
consequence, the nuclear maturity of the oocytes can be evaluated and only
those that have extruded the first polar body are injected. However,
metaphase-II oocytes that have not yet reached cytoplasmic maturity cannot
be recognized. The purpose of this study was to investigate the effect of
different timing of cumulus- corona cell removal and injection on the
outcome of ICSI. For this we allowed the oocytes to complete in-vitro
cytoplasmic maturation in two different culture conditions: (i) surrounded
by their cumulus and corona cells or (ii) totally denuded. We performed
three different studies on sibling oocytes obtained after a standardized
buserelin/human menopausal gonadotrophin (HMG) protocol. We investigated
the effect of early (1-2 h after retrieval) and late (5-6 h after
retrieval) oocyte denudation and injection on the survival and
fertilization of the injected oocytes and on embryo cleavage after
fertilization. We found no statistically significant differences between
early and late injection, indicating that after a standardized
buserelin/HMG protocol the metaphase-II oocytes do not need time for
further cytoplasmic maturation. Furthermore, a different timing of
cumulus-corona cell removal has no effect on the outcome of ICSI,
suggesting that the surrounding cells are not necessary for survival,
fertilization and cleavage after ICSI.
相似文献