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排序方式: 共有1924条查询结果,搜索用时 15 毫秒
1.
Atul K. Sharma Moira S. Mills Vijay L. Grey Keith N. Drummond 《Pediatric nephrology (Berlin, Germany)》1997,11(6):711-713
Accurate, timed urine collections for the measurement of glomerular filtration rate (GFR) may be impractical in infants or
in patients with urological abnormalities. GFR may be measured without urine collection using a constant subcutaneous infusion
of iothalamate. We compare the infusion clearance with conventional renal clearance in 14 children and young adults. The mean
clearance ratio (infusion clearance/renal clearance ± 1 SD) was 0.99±0.1 and the mean discrepancy between the two methods
was 8.5%±4.7%. The 95% limits of agreement for the ratio of the two methods are 0.83–1.23. These data indicate that subcutaneous
infusion of iothalamate is a practical method for measuring GFR in children without a urine collection.
Received March 18, 1996; received in revised form February 12, 1997; accepted March 26, 1997 相似文献
2.
Summary We present a simple method for the isolation of DNA from agarose gels that is economic, fast, and independent of electrical equipment. DNA fragments of up to 6 kb can be easily extracted within 5 min using a disposable plastic syringe and filter paper. Total extraction of DNA fragments between 10 and 20 kb in size is achieved by concentrating the DNA flushed from the gel in a DNA-binding column. 相似文献
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Harry L June Rancia Cummings William J A Eiler Katrina L Foster Peter F McKay Regat Seyoum Marin Garcia Shannan McCane Collette Grey Stephanie E Hawkins Dynesha Mason 《Neuropsychopharmacology》2004,29(2):285-299
The exact opioid-sensitive receptors participating in EtOH-seeking behaviors remains unclear. Previous studies have reported higher densities of micro-opioid receptor binding in the nucleus accumbens (NACC) of P relative to NP rats; however, no differences were seen in delta-receptor binding. In contrast to the NACC, substantially lower levels of micro-receptor binding have been observed in the ventral tegmental area (VTA) of both P and NP rats, albeit no line differences have been observed. In the present study, opioid receptors in the NACC, VTA, and hippocampus were evaluated for their capacity to regulate both EtOH- and saccharin-motivated behaviors in the genetically selected alcohol-preferring (P) rat. To accomplish this, nalmefene, an opiate antagonist with preferential binding affinity for the micro-opioid receptor was unilaterally or bilaterally infused during concurrent availability of 1 h daily EtOH (10% v/v) and saccharin (0.025 or 0.050% w/v) solutions. Rats performed under a two-lever fixed ratio (FR) schedule in which four responses on one lever produced the EtOH solution, and four on a second lever produced the saccharin solution. The results demonstrated that when responding maintained by both EtOH and saccharin are matched at basal levels, unilateral (1-60 microg) or bilateral (0.5-10 microg) microinjections of nalmefene into the NACC produced selective dose-dependent reductions on responding maintained by EtOH. Unilateral (40, 60 microg) and bilateral (10 microg) VTA infusions were also observed to selectively reduced EtOH responding; however, greater nalmefene doses were required and the magnitude of suppression on EtOH responding was markedly less compared with the NACC. The greater sensitivity of nalmefene to suppress EtOH responding in the NACC is likely due to the greater number of opioid receptors in the NACC relative to the VTA. Only bilateral infusion of the 40 microg dose in the NACC and VTA suppressed responding maintained by both EtOH and saccharin. In contrast, intrahippocampal infusions dose dependently suppressed EtOH- and saccharin-maintained responding over a range of doses (1-20 microg). The present study provides evidence that nalmefene suppresses EtOH-motivated behaviors via blockade of opioid receptors within the NACC and VTA, and under various dose conditions both reinforcer and neuroanatomical specificity can be observed. 相似文献
5.
Lynne S. Schilling RN PhD Margaret Grey DrPH FAAN CPNP & Kathleen A. Knafl PhD 《Journal of advanced nursing》2002,37(1):87-99
AIM: An evolutionary concept analysis was undertaken to clarify the concept of self-management of type 1 diabetes in children and adolescents. BACKGROUND: Several problems exist in the literature on self-management of type 1 diabetes in children and adolescents. There is no uniform terminology and there is no uniform definition of the concept. Also, there is no differentiation in the literature between self-management of diabetes in children and adults. METHODS: Ninety-nine references were reviewed and analysed in the disciplines of nursing, medicine, and psychology. After separate analyses revealed no significant differences across disciplines, the analyses were combined to describe the attributes, antecedents, consequences, and surrogate and related concepts. RESULTS: The three essential attributes of the concept were identified as process, activities, and goals. Self-management of type 1 diabetes in children and adolescents is an active and proactive process; it is daily, lifelong, and flexible, and it involves shifting and shared responsibility for diabetes care tasks and decision-making between child and parent. It is a process that involves collaboration with health care providers. Self-management of type 1 diabetes in children and adolescents also consists of varied and many activities related to giving insulin, monitoring metabolic control, regulating diet and exercise, to name just a few. The concept also involves goals, which may differ from one parent/child dyad to another. A working definition of the concept is suggested. CONCLUSIONS: It is hoped that a more uniform definition of the concept will enable researchers to continue investigating antecedents and consequences of the concept in a way that allows for aggregating results. 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
9.
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
10.
The purpose of this pilot study was to determine the effects of the addition of coping skills training for obese multiethnic parents whose overweight children were attending a weight management program. At 6 months, parents in the experimental group had significantly lower body mass index (BMI) and body fat percentage (BFP) and higher numbers of pedometer steps compared with those in the control group. Parents in the experimental group also demonstrated significant improvement in interpersonal relationships, behavior control, and stress management compared with those in the control group. Children in the experimental group demonstrated trends toward decreased BMI and BFP and increased pedometer steps. 相似文献