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51.
Little is known about the family care of older adults in Mexico and the role of women in this process. To begin to fill this knowledge gap, this paper describes how a small sample of low-income women in one Mexico City neighborhood conceptualized the caregiver role and identified the forms of assistance they gave to their older relatives on a daily basis. A grounded theory approach was used to collect and analyze the data. Forty-one semi-structured qualitative interviews were conducted with female caregivers. The age of participants was between 19 and 83 years, and care recipients between 56 and 92 years. The relationship of caregiver to care recipient was wife, daughter, daughter-in-law, granddaughter, sibling, and other relative. The mean length of time providing care was 5 years. Most participants were not employed outside the home, and the median monthly household income was 2000 pesos. We found that caregiving was a life-changing event, with 27 of 41 participants viewing themselves as guardians. Caregivers' emphasis was on care recipients' emotional needs in order to provide “the most precious gift” of “time and attention.” Two forms of assistance were ‘keeping company’ and ‘watching out’ as safeguards against poor health or further decline in health. These findings increase the cultural understanding of caregiving in Mexico. Further research is needed to test the caregiving concepts identified in this study.  相似文献   
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Qualitative visual inspection and manual muscle testing are traditional methods of evaluation that may overlook subtle weakness of the axioscapular musculature. A modification of the standard technique of Moiré topographic analysis of spinal deformity was applied to assess axioscapular muscle function in 51 subjects: 22 asymptomatic individuals, 22 with shoulder instability, and seven with impingement syndrome. Static Moiré evaluation demonstrated scapulothoracic asymmetry or increased topography in 14% of asymptomatic subjects, compared with 32% and 57% in the instability and impingement groups, respectively. The dynamic Moiré test demonstrated an abnormal Moiré pattern in 18% of asymptomatic individuals, compared with 64% and 100% in the instability and impingement groups, respectively. Axioscapular muscle dysfunction is common with both instability and impingement syndrome of the shoulder, although it remains to be determined whether this represents a primary or secondary phenomenon.  相似文献   
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PURPOSE: The use of opioids in labour analgesia has primarily been as an adjuvant to local anesthetics. For early labour, satisfactory analgesia with epidural sufentanil alone is possible. This study evaluates the impact of epinephrine on sedative side effects and analgesia related to the latter technique. METHODS: After Institutional Review Board approval and informed consent this prospective, randomized, double-blind study evaluated 43 nulliparous subjects requesting epidural analgesia. The study site, a tertiary care obstetric unit, accommodates 3500-4500 deliveries annually. Group selection was randomized and blinded by selection of a sealed envelope containing a number which corresponded to a premixed labelled syringe of saline or epinephrine (100 microg/mL). An epidural catheter was placed in a standardized fashion. All subjects received 40 microg of sufentanil and 0.5 mL from the premixed syringe, diluted to 10 mL with NaCl. A blinded observer collected data on maternal sedation, lightheadedness, hemodynamics, oxygenation, and fetal heart rate over a one-hour period following sufentanil injection. RESULTS: The addition of epinephrine significantly (P <0.05) reduced the incidence of sedation and lightheadedness after epidural sufentanil at all data collection points, except two. Analgesic duration was also significantly prolonged by this addition (120 +/- 56 vs 84 +/- 32 min). Maternal satisfaction was high regardless of solution. CONCLUSION: Forty micrograms of epidural sufentanil produces satisfactory analgesia in early labour. The addition of epinephrine improves the side effect profile of this technique while prolonging the duration of analgesia. Epidural sufentanil requires attention to maternal monitoring of oxygenation as maternal desaturation occurred in both groups.  相似文献   
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The background problem associated with the use of streptavidin in detecting biotin-labelled probes hybridized to DNA in crude bacterial extracts has been investigated. We have found that streptavidin binds specifically to a limited number of polypeptides which are difficult to remove by rapid extraction processes. Altering the hybridization and detection protocols results in a marked but not complete reduction of non-specific background in streptavidin-biotin assays. Complete elimination of non-specific background was achieved only when streptavidin was replaced with antibodies for the detection of biotinylated or sulphone-modified probes. The antibody-sulphone and streptavidin-biotin dot blot assays described here require 4.5-5 hours to perform and can detect DNA sequences in samples extracted from 2 x 10(7) cells or fewer.  相似文献   
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Objective: To retrospectively review the management of adenocarcinomain situof the uterine cervix, to determine the outcome of conization versus hysterectomy, and to compare the results achieved by different methods of conization. Methods: We performed a retrospective pathology and chart review of 46 patients with cervical adenocarcinomain situfrom January 1980 to October 1994. Results: Nine patients were managed during the first half of the study period and 37 were managed in the second half. The mean age of patients was 38.4 years (range 25–72). Forty-five of 46 patients were diagnosed as a result of an abnormal Pap smear, although only 19 smears indicated adenocarcinomain situor other glandular abnormalities. Cold knife conization resulted in a 33% rate of positive margins for adenocarcinomain situcompared to 50% for large loop excision of the transformation zone (LLETZ). Among 24 conservatively managed patients with negative conization margins, there have been 2 (8.3%) recurrences of adenocarcinomain situ.Among patients not undergoing hysterectomy as definitive treatment, 1 of 18 (6%) patients undergoing cold knife conization recurred, compared to 4 of 14 (29%) managed with LLETZ, despite a 63.4-month shorter mean follow-up interval for the LLETZ patients. Conclusions: Cold knife conization is associated with a lower rate of recurrence of cervical adenocarcinomain situcompared to LLETZ. We recommend cold knife conization for patients who are not treated with hysterectomy.  相似文献   
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Melatonin (MT) release from the pineal gland has been used as a marker for central noradrenergic function in major depression. Norepinephrine acts at both alpha and beta adrenergic receptors on the pinealocyte membrane to mediate nocturnal MT release, but in humans the contribution of each receptor class is unclear. In order to explore the effect of alpha 2 receptors on MT release, 10 female subjects were given oral challenges, in separate placebo-controlled trials, of either 10.8 mg of yohimbine, an alpha 2 adrenergic antagonist, or clonidine, a partial alpha 2 adrenergic agonist, at doses of either 200 micrograms or 300 micrograms. Post-challenge serum melatonin was measured from 18:00 h to 22:00 h in both studies as was urinary 6-sulphatoxy-melatonin (aMT6s), the major metabolite of MT (from 18:00 h to 22:00 h, and from 22:00 h to 10:00 h). Growth hormone (GH) was also assayed following the clonidine challenge, and blood pressure, pulse rate, and side effects were monitored after both challenges. Neither yohimbine nor clonidine significantly altered nocturnal serum MT levels compared to placebo. However, there was a significant increase in urinary aMT6s between 18:00 h and 22:00 h following yohimbine ingestion. Yohimbine ingestion produced significant rises in pulse rate and the urge to urinate compared to placebo. Both doses of clonidine resulted in a significant reduction in pulse rate, systolic and diastolic blood pressure, and significant increases in drowsiness and other measures of sedation following ingestion. Only clonidine 300 micrograms produced a significant elevation in GH release. This study highlights the limitations of oral neuroendocrine challenge studies.  相似文献   
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Computer based 3-dimensional reconstruction transforms 2-dimensional intravascular ultrasound images into a longitudinal format facilitating analysis of luminal narrowing. To validate the accuracy of current software in measuring coronary artery diameter and cross-sectional area, in arteries with atherosclerosis, we performed 3-dimensional reconstruction in 10 human pathologic coronary arterial segments of 10-25mm length. Images were obtained using a 4.8 French catheter with pullback speed of 1mm/sec acquired at 3 frames/sec onto VHS tape. The data were digitized and intraluminal 3-dimensional reconstruction performed using a voxel-based program. Pathologic sections were obtained every 3mm, and dimensions were measured with a resolution of 0.01 mm. Maximum, minimum, and 3 other representative diameters were recorded by an observer blinded to the ultrasound diameters. Average histo-pathologic diameters were reported, and specimen cross-sectional area was then calculated. Results: In 53 sections, pathological diameters ranged from 1.4-4.5mm (mean 2.7 +/- 0.68mm) while 3-dimensional reconstructed diameters were 1.9 to 3.8mm (mean 2.6 +/- 0.54mm). Pathologic and ultrasound derived 3-dimensional reconstruction diameters had an excellent correlation (r=0.86, SEE=+/-0.36). Pathology and 3-dimensional reconstruction cross-sectional area also correlated closely (r=0.88, SEE=+/-1.50). Diameters less than 2.0mm were systematically overestimated and diameters greater than 3.5mm underestimated by 3-dimensional reconstruction. Most 3 dimensional reconstruction values were within +/- 10% of pathology, but diverged at each diameter extreme, approaching +/- 20%. Thus, computerized 3-dimensional reconstruction of ultrasound images shows excellent quantification of luminal size in the 2.0-3.5mm range, suggesting important investigative and clinical applications.  相似文献   
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