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21.
22.
Genomic DNA from 19 Japanese patients with congenital lipoid adrenal hyperplasia (lipoid CAH) representing 16 different families was examined to identify the genetic alterations of steroidogenic acute regulatory protein (StAR). Ten of 19 patients had a 46,XX karyotype and nine had a 46,XY karyotype. Six of the 46,XX patients have experienced spontaneous pubertal changes including breast development and irregular menstruation whereas none of the 46,XY subjects displayed pubertal changes. Eight different mutations were identified. Sixteen patients were either homozygotes or compound heterozygotes for the Q258X mutation. The seven other mutations identified were 189delG, 246insG, 564del13bp, 838delA, Q212X, A218V and M225T. The 189delG, 246insG, 546del13bp and Q212X mutants encode truncated proteins. COS-1 cells transfected with expression vectors encoding cDNAs for the mutant StAR proteins which affect the C-terminus, 838delA, A218V and Q258X, exhibited no steroidogenesis enhancing activity. However, the M225T mutant retained some steroidogenic activity. The patient with the M225T mutation had late onset of this disorder and some capacity to secrete testosterone in response to hCG. These findings suggest: (i) that the Q258X mutation can be used as a genetic marker for the screening of Japanese for lipoid CAH, (ii) that the C-terminus of StAR plays an important role in the protein's activity and (iii) that there are differences in the extent of functional impairment of the testis and ovaries in lipoid CAH.   相似文献   
23.
Superoxide, an agent which attenuates the half-life of nitric oxide, is metabolized and synthesized by superoxide dismutase (SOD) and xanthine oxidase, respectively. Over the last few years much work has focused on the role of nitric oxide in human parturition. The aim of this study was to determine whether the onset of human parturition is associated with a change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD), manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the uterus. Samples of myometrium, placenta, decidua and fetal membranes were obtained from women before and after the onset of labour at term. Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like immunoreactivity was detected in syncytiotrophoblast cells, villous stromal cells and endothelial cells of blood vessels in the placenta. In the myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial cells and to some vascular smooth muscle cells. In the fetal membranes we observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion, extravillous trophoblast and decidua. There was no difference in SOD enzyme activity or staining intensity for SOD between different cell types before and during labour. Xanthine oxidase immunoreactivity was identified in each of the tissues examined and again there was no difference in immunostaining in tissues obtained from women delivered before or after the onset of labour. These results show that the pregnant uterus is capable of both synthesizing and degrading superoxide and suggest that superoxide dismutase and xanthine oxidase may play a role in the maintenance of uterine quiescence during pregnancy, but not in the initiation of parturition.   相似文献   
24.
Oxygen radical generation is known to be detrimental to sperm function, especially motility, through the lipid peroxidation of the membranes. Generation of reactive oxygen species can be induced by leukocyte contamination, sperm centrifugation and the presence of abnormal spermatozoa with excess residual cytoplasm. This study aims to evaluate the effect on sperm motility of incubation in an antioxidant-containing solution, during liquefaction and centrifugation. Thirty semen samples were each divided into two equal parts: one mixed with Tyrode's solution, the other with a salt solution containing antioxidants (Sperm- Fit; Ellios Bio-Media, Paris, France). All the procedures were identical in the two groups. The ratio of leukocytes to spermatozoa was significantly correlated with the motility after liquefaction and after a 24 h incubation in routine in-vitro fertilization (IVF) medium and with the number of motile spermatozoa recovered after Percoll preparation. Moreover, when this ratio was > or = 0.2, all motility parameters were lowered. Incubation with Sperm-Fit allowed a higher percentage of motility after Percoll preparation when the ratio was > or = 0.2 (48 +/- 5% versus 41 +/- 6% for Sperm-Fit and Tyrode's solution respectively; P < 0.05) and a greater number of motile spermatozoa recovered after Percoll preparation, whatever the ratio (3.2 +/- 1.0 x 10(6) versus 2.4 +/- 0.7 x 10(6) for Sperm-Fit and Tyrode's solution respectively when ratio > or = 0.2; 18.1 +/- 3.4 x 10(6) versus 14.4 +/- 2.9 x 10(6) for Sperm-Fit and Tyrode's solution respectively when ratio < 0.2; P < 0.05). These results show that incubation with antioxidants during liquefaction and centrifugation increases recovery of motile spermatozoa.   相似文献   
25.

Background

Primary care is increasingly interested in the identification of frailty, as it selects the target population for integrated care. However, instruments for the identification of frailty specifically validated for use in primary care are scarce. This study developed the Easycare Two-step Older persons Screening (Easycare-TOS), which provides a valid, efficient, and pragmatic screening procedure to identify frail older people.

Aim

This paper aims to describe the development of the Easycare-TOS and the data from the pilot studies.

Design and setting

Observational pilot study in seven academic GP practices in and around Nijmegen, The Netherlands.

Method

The Easycare-TOS was developed in a cyclic process with the input of stakeholders. In every cycle, the requirements were first defined, then translated into a prototype that was tested in a pilot study. The Easycare-TOS makes optimal use of prior knowledge of the GP, and the professionals’ appraisal is decisive in the frailty decision, instead of a cut-off score. Further, it considers aspects of frailty, as well as aspects of the care context of the patient.

Results

The pilot data have shown that after step 1, two-thirds of the patients do not need further assessment, because they are judged as not frail, based on prior knowledge of the GP. The overall prevalence of frailty in this pilot study is 24%. Most professionals who participated in the pilot studies considered the time investment acceptable and the method to be of added value.

Conclusion

The Easycare-TOS instrument meets the predefined efficiency, flexibility, and acceptability requirements for use as an identification instrument for frailty in primary care.  相似文献   
26.
A growing literature shows prominent sex effects for risk for post‐traumatic stress disorder and associated medical comorbid burden. Previous research indicates that post‐traumatic stress disorder is associated with reduced slow wave sleep, which may have implications for overall health, and abnormalities in rapid eye movement sleep, which have been implicated in specific post‐traumatic stress disorder symptoms, but most research has been conducted in male subjects. We therefore sought to compare objective measures of sleep in male and female post‐traumatic stress disorder subjects with age‐ and sex‐matched control subjects. We used a cross‐sectional, 2 × 2 design (post‐traumatic stress disorder/control × female/male) involving83 medically healthy, non‐medicated adults aged 19–39 years in the inpatient sleep laboratory. Visual electroencephalographic analysis demonstrated that post‐traumatic stress disorder was associated with lower slow wave sleep duration (F(3,82) = 7.63, = 0.007) and slow wave sleep percentage (F(3,82) = 6.11, = 0.016). There was also a group × sex interaction effect for rapid eye movement sleep duration (F(3,82) = 4.08, = 0.047) and rapid eye movement sleep percentage (F(3,82) = 4.30, = 0.041), explained by greater rapid eye movement sleep in post‐traumatic stress disorder females compared to control females, a difference not seen in male subjects. Quantitative electroencephalography analysis demonstrated that post‐traumatic stress disorder was associated with lower energy in the delta spectrum (F(3,82) = 6.79, = 0.011) in non‐rapid eye movement sleep. Slow wave sleep and delta findings were more pronounced in males. Removal of post‐traumatic stress disorder subjects with comorbid major depressive disorder, who had greater post‐traumatic stress disorder severity, strengthened delta effects but reduced rapid eye movement effects to non‐significance. These findings support previous evidence that post‐traumatic stress disorder is associated with impairment in the homeostatic function of sleep, especially in men with the disorder. These findings suggest that group × sex interaction effects on rapid eye movement may occur with more severe post‐traumatic stress disorder or with post‐traumatic stress disorder comorbid with major depressive disorder.  相似文献   
27.
Myelinated and nonmyelinated nerves: comparison of proton MR properties   总被引:1,自引:0,他引:1  
Jolesz  FA; Polak  JF; Adams  DF; Ruenzel  PW 《Radiology》1987,164(1):89-91
The magnetic resonance (MR) relaxation rates of protons were compared in the myelinated and nonmyelinated nerves of the garfish. The long, large olfactory nerve of the garfish, as an easily accessible source of nonmyelinated axons, is uniquely suited for such a comparison. The T1 and T2 measurements revealed distinct and consistent differences between nonmyelinated olfactory nerves and myelinated optic and oculomotor nerves. Comparisons between water content, lipid content, and relaxation rates indicated that the differences in MR properties represent complex differences in the distribution and physical environment of the constituent lipid and water protons.  相似文献   
28.

Background

Focusing on high-value delivery of health care, we describe our implementation of telephone postoperative visits as alternatives to in-person follow-up after routine, low-risk surgery in an urban setting. Our pilot program assessed telephone postoperative visit feasibility as well as patient satisfaction and clinical outcomes.

Methods

We offered telephone postoperative visits to all clinically eligible, in-state patients scheduled for appropriate low-risk operations. An advanced practitioner conducted the telephone postoperative visit within 2 weeks of the operation and discharged patients from routine follow-up if recovery was satisfactory. We reviewed the medical records to identify encounters and adverse events in the 30-day postoperative period.

Results

Telephone postoperative visits were opted for by 92/94 (98%) clinically eligible, in-state patients. Most patients cited convenience (55%), travel (34%), and time (22%) as their main motivations. The average patient opting in was 55?±?16 years old (range 23–88, 8%?>?65) and lived 22?±?26 miles from our clinic (range 0.9–124). Of 50 patients completing telephone postoperative visits, 48 (96%, 2 were not asked) were satisfied with the telephone postoperative visit as their sole postoperative visit, 44 (88%) of whom required no additional follow-up. On average, telephone postoperative visits lasted 8.6?±?3.9 minutes, compared with the 82.8?±?33.4 minutes for preintervention, postoperative visit time. Adding travel times, we estimate each patient saved an average of 139–199 minutes or 94–96% of the time they would have spent coming to clinic. No instances of major morbidity or mortality were identified on chart review.

Conclusion

Many patients find telephone postoperative visits more convenient than in-clinic visits. Moreover, estimates of time saved are compelling. Amid changing regulations and reimbursement, our findings support the growing use of telehealth for postoperative care of routine, low risk operations.  相似文献   
29.
Surface shield: device to reduce personnel radiation exposure   总被引:2,自引:0,他引:2  
A simple device is described that can reduce personnel exposure from scatter radiation by up to 75%. The device consists of an oblong piece of shielding (0.75-mm lead equivalent) that is taped to the side of the patient during percutaneous renal stone removal and other interventional procedures. Contrary to other shields and barriers, this does not interfere with access to the patient. Scatter exposure data from phantom studies are presented and the rationale for surface shielding discussed.  相似文献   
30.
We studied the effects of increasing threat conditions on self-reported emotion, eyeblink electromyogram, and skin conductance responses to startling sounds in 55 police officers who endorsed a range of PTSD (posttraumatic stress disorder) symptoms. We found that contextual threat affected both physiologic and self-reported emotional responses. Greater PTSD symptom severity was related to greater physiologic responses under the low and medium but not under the high threat condition. The relationship between PTSD symptoms and physiologic responses was neither explained by self-reported emotional responses nor preexisting reported exaggerated startle symptoms. Our results emphasize the importance of contextual threat and suggest that laboratory measures of startle improve upon self-reported exaggerated startle alone in indexing PTSD symptom severity in urban police officers.  相似文献   
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