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51.
Ashley Aluko Denis A. Vaughan Anna M. Modest Alan S. Penzias Michele R. Hacker Kim Thornton Denny Sakkas 《Reproductive biomedicine online》2021,42(3):572-578
Research questionDo multiple cryopreservation–warming cycles, coupled with blastocyst biopsy, negatively affect IVF outcomes?DesignPatients undergoing IVF with homologous single embryo transfer, and who underwent trophectoderm biopsy for preimplantation genetic testing for aneuploidy (PGT-A) between 2013 and 2017, were divided into three groups based on degree of embryonic micromanipulation: once-biopsied, once-cryopreserved (group BC, n = 2603), once-biopsied, twice-cryopreserved (group CBC, n = 95) and twice-biopsied, twice-cryopreserved (group BCBC, n = 15). The primary outcome was live birth; secondary outcomes included positive serum pregnancy test, clinical pregnancy and miscarriage.ResultsGroup CBC had a significantly lower chance of live birth (adjusted RR 0.57, 95% CI 0.41 to 0.79) and clinical pregnancy (adjusted RR 0.67, 95% CI 0.53 to 0.85) compared with group BC. Miscarriage rates were similar between groups BC and CBC (adjusted RR 1.3, 95% CI 0.64 to 2.7).ConclusionsMultiple cryopreservation–warming cycles, coupled with blastocyst biopsy, negatively affect IVF outcomes. Although PGT-A is thought to improve reproductive outcomes on a per transfer basis, caution must be exercised in counselling patients on the possibility of diminishing returns owing to further embryonic micromanipulation after an embryo has been cryopreserved. 相似文献
52.
Objective
to gain insight into the experiences and perspectives of pregnant women diagnosed antenatally with fetal lower urinary tract obstruction (LUTO) participating in an interventional fetal medicine randomised controlled trial (RCT).Design
a qualitative study using semi-structured interviews. Interviews were analysed using Riessman's narrative analysis.Setting
fetal medicine clinics within the United Kingdom National Health Service (NHS).Participants
five pregnant women who were recruited as part of an RCT and two additional women who were recruited after the trial was terminated before completion.Findings
three themes were identified and form the basis of this article: the use of technology in pregnancy, the loss of a normal pregnancy, and decision making in uncertainty.Implications and conclusions
undertaking qualitative research within an RCT can illuminate the experience of the condition being studied. Women's experience of a pregnancy where LUTO was diagnosed in the fetus entailed an emotional journey following the visualisation of the abnormality through the use of routine ultrasound screening. Women tried to make sense of the diagnosis in order to make the best, albeit less than ideal, decisions for themselves, their baby, and their family. Midwives are in a good position to support women through the emotional distress of diagnosis and to help them negotiate the uncertain terrain in which they make decisions. 相似文献53.
Elevated serum levels of tumor necrosis factor are associated with progressive encephalopathy in children with acquired immunodeficiency syndrome 总被引:17,自引:0,他引:17
M Mintz R Rapaport J M Oleske E M Connor M R Koenigsberger T Denny L G Epstein 《American journal of diseases of children (1960)》1989,143(7):771-774
The cytokine tumor necrosis factor (TNF) was assayed in the sera (n = 31) and cerebrospinal fluid (n = 26) of children with acquired immunodeficiency syndrome, using a competitive radioimmunoassay. Elevated serum levels of TNF were found in 15 (79%) of 19 patients with progressive encephalopathy (PE), compared with 1 (8%) of 12 patients without neurologic involvement. There was a significant association of PE with elevated serum TNF levels. Conversely, of 16 patients with elevated serum TNF levels, 15 (94%) were found to have PE, and of 8 patients with serum TNF levels greater than 100 pg/ml, all 8 (100%) had PE. No association was found between cerebrospinal fluid levels of TNF and PE. Neither serum nor cerebrospinal fluid TNF levels correlated with the degree of cachexia. These data suggest that circulating TNF may be responsible for the myelin damage that occurs in human immunodeficiency virus type 1-associated PE. 相似文献
54.
Vitamin D (soltriol), light, and reproduction 总被引:2,自引:0,他引:2
Evidence from autoradiographic studies with 1,25(OH)2-vitamin D3 (vitamin D, soltriol) labeled with tritium and from the literature indicates that the steroid hormone soltriol regulates and modulates reproductive processes in the female, as it does in the male. Nuclear receptors for soltriol have been discovered in the uterus, oviduct, ovary, mammary gland, placenta, and fetal membranes, as well as in the pituitary and hypothalamus. Soltriol is recognized as a transducer and hormonal messenger of sunlight, acting as a somatotropic activator and modulator of vital processes for the seasonal and estival adaptation of growth, development, and procreation. Its influence on calcium equilibrium is just one of its many functions to serve this goal. This article reviews experimental, clinical, and epidemiologic evidence that suggests the involvement of soltriol in the control of reproductive processes, noting its importance for the onset of puberty, fertility, pregnancy, lactation, and probably sexual behavior. Cooperative actions between soltriol and other steroid hormones, especially estradiol, are pointed out. 相似文献
55.
We report cerebral blood flow (CBF) values for healthy neonates in five gestational age categories for 9 single and 7 combination measures of continuous wave Doppler ultrasound. Combinations of measures, particularly those from the anterior cerebral artery with a 5.0 MgH probe, increased the reliability and validity. The most reliable and valid single measure was mean flow velocity from the anterior cerebral artery (5.0 MgH probe). CBF values were lower for neonates with respirator support than for neonates without respirator support. No significant differences were found in CBF measures between intubated neonates who developed IVH and intubated neonates who did not develop IVH. Neonates who were intubated and developed intraventricular hemorrhage (IVH) were treated more vigorously than those who were intubated and did not develop IVH. By day 6, neonates with IVH had a significantly higher mean pH, mean serum bicarbonate, and mean positive base balance. 相似文献
56.
We have used stopped-flow spectrophotometry and the sodium dodecyl sulfate sequestration technique to study the kinetics of dissociation of DNA complexes of the mixed topoisomerase I/II poison N-[2-(dimethylamino)ethyl]acridine-4-carboxamide (termed DACA) and a range of related linear tricyclic carboxamides with neutral chromophores. Complexes of DACA and related acridine and phenazinecarboxamides bearing an N,N-dimethylaminoethyl side chain dissociate from calf thymus DNA by a kinetic pathway involving four discernible steps in a manner similar to complexes of N-[(2-dimethylamino)ethyl]-9-aminoacridine-4-carboxamide (termed 9-amino-DACA). We infer from these findings that the side chains of DACA, its phenazine homologue, and 9-amino-DACA make comparable interactions with the DNA base pairs. In the case of 9-amino-DACA, a selective topoisomerase II poison, these are known, by crystallographic analysis, to involve hydrogen-bonding interactions between the protonated dimethylammonium group of the side chain and the O6/N7 atoms of guanine and to include a bridging water molecule hydrogen bonded to the carboxamide group and a phosphate oxygen. By contrast, we find that other linear tricyclic carboxamides with neutral chromophores which lack a peri nitrogen atom and are biologically inactive dissociate from DNA by a different mechanism in which it appears their side chains fail to interact with guanine. We conclude that the ability of the carboxamide group to lie preferentially in the plane of the chromophore, so facilitating the dimethylammonium-guanine hydrogen bond and ensuring maintenance of the water-bridged carboxamide-phosphate interaction, is a critical requirement for antitumor activity among ligands of the linear tricyclic carboxamide class. However, unlike the situation for 9-amino-DACA, for ligands with uncharged chromophores containing peri nitrogen atoms such as DACA, this outcome is possible with the 4-carboxamide group rotated cis or trans with respect to the ring nitrogen. This difference may have relevance to the ability of DACA to be a dual poison of both topoisomerases I and II. 相似文献
57.
Saliva: a fountain of opportunity 总被引:1,自引:0,他引:1
58.
Socioeconomic and demographic factors can affect the impact of telehealth education programs that use interactive compressed video technology. This study assessed program satisfaction among participants in the University of Arkansas for Medical Sciences' School Telehealth Education Program delivered by interactive compressed video. Variables in the one-group posttest study were age, gender, ethnicity, education, community size, and program topics for years 1997-1999. The convenience sample included 3,319 participants in junior high and high schools. The School Telehealth Education Program provided information about health risks, disease prevention, health promotion, personal growth, and health sciences. Adolescents reported medium to high levels of satisfaction regarding program interest and quality. Significantly higher satisfaction was expressed for programs on muscular dystrophy, anatomy of the heart, and tobacco addiction (p < 0.001 to p = 0.003). Females, African Americans, and junior high school students reported significantly greater satisfaction (p < 0.001 to p = 0.005). High school students reported significantly greater satisfaction than junior high school students regarding the interactive video equipment (p = 0.011). White females (p = 0.025) and African American males (p = 0.004) in smaller, rural communities reported higher satisfaction than White males. The School Telehealth Education Program, delivered by interactive compressed video, promoted program satisfaction among rural and minority populations and among junior high and high school students. Effective program methods included an emphasis on participants' learning needs, increasing access in rural areas among ethnic groups, speaker communication, and clarity of the program presentation. 相似文献
59.
Treatment of chronic pain by using intrathecal drug therapy compared with conventional pain therapies: a cost-effectiveness analysis 总被引:4,自引:0,他引:4
OBJECT: The object of this study was to compare the cost-effectiveness of intrathecal drug therapy (IDT) with that of conventional pain therapy (CPT) in patients suffering from chronic low back pain caused by failed back syndrome. In this study, the authors tabulated actual costs, in Canadian dollars, in a consecutive series of patients undergoing IDT within the Canadian health care system and have compared them with costs in a control group in the same environment. The influence of these treatments on the quality of life (QOL) was also analyzed. METHODS: The authors report on a series of 67 patients suffering from failed back syndrome, 23 of whom underwent implantation of a programmable drug delivery pump and 44 of whom acted as controls. Patients were followed for a 5-year period during which the investigators tabulated the actual costs incurred for diagnostic imaging, professional fees, implantation costs including hardware, nursing visits for maintenance of the pumps, alternative therapies, and hospitalization costs for breakthrough pain. From this data, cumulative costs for each group were calculated for a 5-year period. Patient responses on the Oswestry Pain Questionnaire were analyzed to assess the impact of treatment on QOL. The actual cumulative costs for IDT during a 5-year period were $29,410, as opposed to $38,000 for CPT. High initial costs of equipment required for IDT were recovered by 28 months. After this time point, managing patients with CPT became the more expensive treatment option for the remainder of the follow-up period. The Oswestry Disability Index showed a 27% improvement for patients in the IDT group, compared with a 12% improvement in the control group. CONCLUSIONS: In patients who respond to this treatment, IDT is cost effective in the long term despite high initial costs of implantable devices. 相似文献
60.
5,6-Dimethylxanthenone-4-acetic acid (DMXAA) is a novel anticancer agent with a number of unique activities, and is in clinical trial. The current synthesis of DMXAA involves six steps, beginning with a heterogeneous reaction to form an isonitrosoacetanilide, and gives an overall yield of 11% from 2,3-dimethylaniline. We report an alternative synthesis of the key intermediate 3,4-dimethylanthranilic acid via nitration of 3,4-dimethylbenzoic acid and separation of the key desired isomer by ready crystallisation. This, together with improvements in the rest of the synthesis, provide a shorter and higher-yielding route to DMXAA (22% overall from 3,4-dimethylbenzoic acid). 相似文献