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Predictive value of normal sperm morphology: a structured literature review   总被引:12,自引:0,他引:12  
The aim of the study was to conduct a structured review of theliterature published on the use of normal sperm morphology,as an indicator of male fertility potential in the in-vitrofertilization (IVF) situation, and to establish the universalpredictive value of this semen parameter. Published literaturein which normal sperm morphology was used to predict fertilizationand pregnancy, during the period 1978-1996, was reviewed. Atotal of 216 articles were identified by the sourcing methodology,but only 49 provided data that could be tabulated and analysed.Of these, only 18 provided sufficient data for statistical analysis.Fifteen studies used the strict criteria to evaluate sperm morphology,two used World Health Organization (WHO) guidelines and oneused both the strict criteria and the WHO guidelines. All thestudies (n=10) using the 5 and 14% normal sperm morphology thresholds(strict criteria) produced positive predictive values for IVFsuccess. In the prediction of pregnancy, 82% (9/11) and 75%(6/8) of the studies produced positive predictive values whenusing the 5% and 14% thresholds respectively. Aggregating thedata produced around the 5% normal sperm morphology threshold(strict criteria), the overall fertilization rates were 59.3%(1979/3337; per oocyte) for the 4% group and 77.6% (10345/13327;per oocyte) for the >4% group, and the overall pregnancyrates were 15.2% (60/395; per cycle) and 26.0% (355/1368; percycle) respectively. The no-transfer rates across the 5% thresholdwere 24.0% (86/359; per cycle) in the 4% group compared to 7.4%(80/1088; per cycle) in the >4% group. The inclusion of anaccurately evaluated normal sperm morphology count as an integralpart of the standard semen analysis makes this analysis stillthe most cost-effective means of evaluating the male factor.  相似文献   
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Gene therapy is defined as the introduction of a therapeutic gene into a cell, whose expression can lead to a cure of a disease or offer a transient advantage for tissue growth and regeneration. The delivery of genes can be undertaken for a number of purposes, usually it is attempted to enhance or add a function to a cell or a tissue or to delete or reduce another function. In this brief overview we describe various vehicles and techniques that have been developed to deliver therapeutic genes into cells, such as viral vectors and physical/chemical gene delivery methods including naked DNA and particle-mediated gene transfer, the microseeding technique and the application of lipids. Furthermore we review the potential utility of gene therapy from the perspective of a reconstructive surgeon. Several tissues will be discussed, particularly muscle, tendon, nerve, bone, skin and wounds.  相似文献   
25.
In this paper we describe a differentiation sequence amongst adult murine thymocytes which goes from CD4+8+3lo(low) to CD4+8+3int(intermediate) to CD4+8+3hi(high) and then to mature single positive CD3hi thymocytes. Phenotypic characterization of CD4+8+3int/hi cells for a number of other surface markers is consistent with them being in transition from CD4+8+3lo phenotype to mature phenotype. The same observation was made for sensitivity towards ionomycin-mediated apoptosis. In the thymus of Mls-1a mice, where autoreactive TCR-V beta 6+ cells are negatively selected, deletion of TCR-V beta 6+ cells was first detected in the CD4+8+3int subset, and was complete by the CD4+8+3hi stage, suggesting that up-regulation of the TCR/CD3 complex is required for deletion of Mls-1a autoreactive thymocytes. No sign of apoptosis was detected among any fresh thymocyte subsets suggesting that apoptotic cells are rapidly cleared from the thymus. The CD4+8+3int/CD4+8+3hi cells are therefore populations in transit from the typical cortical thymocytes to the mature T-cells.  相似文献   
26.
The aim of this study is to propose a model of the benefits and working mechanisms of family nursing conversations in home healthcare from the perspective of participating patients and their family members. Family nursing conversations in this study are intended to optimise family functioning, improve collaboration between family and professional caregivers and ultimately prevent or reduce overburden of family caregivers. In a qualitative grounded theory design, data were collected in 2017 using intensive interviewing with participants of family nursing conversations in home healthcare. A total of 26 participants (9 patients and 17 family members) from 11 families participated in a family nursing conversation and the study. Seven nurses who received extensive education in family nursing conversations conducted them as part of their daily practice. Interviews occurred 4–6 weeks after the family nursing conversation. The model that was constructed in close collaboration with the families consists of three parts. The first part outlines working mechanisms of the conversation itself according to participants, i.e. structured and open communication about the care situation and the presence of all of the people who are involved. The second part consists of the benefits that participants experienced during and immediately after the conversation – an increased sense of overview and improved contact among the people involved – and the related working mechanisms. The last part consists of benefits that emerged in the weeks after the conversation – reduced caregiver burden and improved quality of care – and the related working mechanisms. Insight into the benefits and working mechanisms of family nursing conversations may assist healthcare professionals in their application of the intervention and provides directions for outcomes and processes to include in future studies.  相似文献   
27.
The Pittsburgh Sleep Diary   总被引:5,自引:3,他引:2  
SUMMARY  Increasingly, there is a need in both research and clinical practice to document and quantify sleep and waking behaviors in a comprehensive manner. The Pittsburgh Sleep Diary (PghSD) is an instrument with separate components to be completed at bedtime and waketime. Bedtime components relate to the events of the day preceding the sleep, waketime components to the sleep period just completed. Two-week PghSD data is presented from 234 different subjects, comprising 96 healthy young middle-aged controls, 37 older men, 44 older women, 29 young adult controls and 28 sleep disorders patients in order to demonstrate the usefulness, validity and reliability of various measures from the instrument. Comparisons are made with polysomnographic and actigraphic sleep measures, as well as personality and circadian type questionnaires. The instrument was shown to have sensitivity in detecting differences due to weekends, age, gender, personality and circadian type, and validity in agreeing with actigraphic estimates of sleep timing and quality. Over a 12–31 month delay, PghSD measures of both sleep timing and sleep quality showed correlations between 0.56 and 0.81 ( n = 39, P < 0.001).  相似文献   
28.
Psychological influences on the perception of immune function   总被引:5,自引:0,他引:5  
BACKGROUND: Perception of deficiencies in immunity are common in a number of patient complaints. However, little is known about the way in which individuals form perceptions about the competence of their immune system. In two studies we examined the relationship between subjects' perceptions of their immune functioning, physical symptoms, mood and measures of immunity. METHODS: In Study 1, 20 healthy volunteers completed global ratings of their immune system functioning, as well as mood and symptom reports, twice a week for 5 weeks. At the same time, blood samples were taken to assess serum IgA, IgG, and IgM antibodies. In Study 2, another sample of 58 subjects completed the same measures weekly for 5 weeks and their blood was tested for concentrations of CD3, CD4, CD8, and CD16 lymphocytes. RESULTS: We found perceptions of immune functioning to be unrelated to the concentrations of serum antibodies or blood lymphocytes. Immune perceptions were strongly related to mood and in particular, feelings of fatigue and vigour. The experience of recent physical symptoms, while not as strong as mood variables, was also important in perceptions of immune functioning. CONCLUSIONS: Mood seems to be an important determinant in the perception of immune function, and complaints about immune dysfunction in clinical situation should be investigated with this possibility in mind.  相似文献   
29.
The effect of vaccination with a formalin-inactivated, alum-precipitated (FI), bovine respiratory syncytial virus (BRSV) vaccine on BRSV induced respiratory disease in calves was investigated. Six month old BRSV-naive calves were vaccinated with either a FI, a modified live virus (MLV), or virus antigen negative control vaccine (n = 4 per group). One month after the second vaccination, the calves were aerosol challenged with lung wash from a newborn calf infected with a field isolate of BRSV. Moderate to severe clinical disease occurred in all calves. Calves that received FI vaccine had a significantly earlier (day 2 vs. day 4-5) onset of pyrexia and dyspnea (P < 0.05). Pulmonary lesions, consisting of cranioventral atelectasis and dorsal emphysema, occurred in all groups. Two calves that received MLV, and three that received FI vaccine, had reduced pneumonic lung area relative to controls. Vaccination with the FI vaccine resulted in more rapid onset of clinical disease, but ultimately, reduced pulmonary pathology in most recipients.  相似文献   
30.
1 The cardiovascular effects of bromocriptine, a dopamine receptor agonist, were investigated in twenty-eight Parkinsonian patients.

2 Bromocriptine caused a significant impairment of postural compensation with a fall in systolic pressure and an absence of the rise in diastolic pressure after standing for 1 min when patients taking active drug were compared to the same patients on placebo. The hypotensive effect persisted for at least 6 weeks of treatment. There was also a significant reduction in supine heart rate.

3 One patient had marked falls in supine and erect blood pressure after a single oral dose of bromocriptine (2.5 mg) and a further patient developed paroxysmal atrial tachyarrhythmias. Both blood pressure and heart rate changes reversed spontaneously after stopping bromocriptine.

4 It is proposed that dopaminergic mechanisms either in the central nervous system or the periphery contribute to cardiovascular regulation in man.

  相似文献   
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