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81.
Nursing for Women's Health convened a group of nurse researchers for a roundtable discussion about the relationship of research to the profession of nursing, how research drives evidence‐based practice and how nurses can get involved in research and in its application to the care of women and newborns.  相似文献   
82.
There is a well‐documented shortage of physician researchers, and numerous training programs have been launched to facilitate development of new physician scientists. Short‐term research training programs are the most practical form of research exposure for most medical students, and the summer between their first and second years of medical school is generally the longest period they can devote solely to research. The goal of short‐term training programs is to whet the students’ appetite for research and spark their interest in the field. Relatively little research has been done to test the effectiveness of short‐term research training programs. In an effort to examine short‐term effects of three different NIH‐funded summer research training programs for medical students, we assessed the trainees’ (N = 75) research self‐efficacy prior to and after the programs using an 11‐item scale. These hands‐on training programs combined experiential, didactic, and mentoring elements. The students demonstrated a significant increase in their self‐efficacy for research. Trainees’ gender, ranking of their school, type of research, and specific content of research project did not predict improvement. Effect sizes for different types of items on the scale varied, with the largest gain seen in research methodology and communication of study findings.  相似文献   
83.
Aromatase is an enzyme complex that is composed of a specific form of cytochrome P-450 and a flavoprotein, NADPH-cytochrome P-450 reductase. Aromatase activity of granulosa cells is increased markedly by follicle-stimulating hormone (FSH) and by analogs of cyclic AMP. It was the objective of the present study to investigate the effects of FSH and dibutyryl cyclic AMP (Bt2cAMP) on the synthesis of NADPH-cytochrome P-450 reductase in rat granulosa cells maintained in vitro. Granulosa cells were obtained from the ovaries of diethylstilbestrol (DES)-treated immature rats and were incubated in the presence of DES (10−7 M), DES + FSH (250 ng/ml), or DES + Bt2cAMP (1 mM) for up to 72 h. After 72 h of incubation, aromatase activity of cells incubated with DES alone was 5 pmoles estrogen formed 2 h−1 mg−1 protein and was increased > 60-fold in cells incubated with FSH or Bt2cAMP. NADPH-cytochrome P-450 reductase was immunoisolated from [35S]methionine-labeled lysates of granulosa cells incubated for 72 h in the absence or presence of stimulatory factors. The rate of synthesis of reductase was found to be increased about 3-fold in cells incubated with DES + FSH or DES + Bt2cAMP as compared to cells incubated with DES alone. By immunoblot analysis we found that the cellular content of reductase was increased about 2-fold by FSH and Bt2cAMP treatment. Reductase specific activity was 10 nmoles min−1 mg−1 protein in membrane fractions of DES-treated cells and was increased 1.6-fold by FSH treatment. These findings are indicative that FSH increases the rate of synthesis, cellular content and specific activity of NADPH-cytochrome P-450 reductase in rat granulosa cells in vitro. The finding that Bt2cAMP causes a similar induction of reductase synthesis is suggestive that the stimulatory effect of FSH on this component of the aromatase enzyme complex is mediated by an increase in cyclic AMP formation.  相似文献   
84.
Background. Transmyocardial laser revascularization (TMR) has been demonstrated effective for relieving angina, although prior studies have yielded inconsistent results regarding postoperative myocardial perfusion and function. This study evaluated long-term changes in myocardial perfusion and contractile reserve after TMR in a model of hibernating myocardium.

Methods. Miniswine had subtotal left circumflex coronary artery occlusion to reduce resting blood flow to 10% of baseline. After 2 weeks in the low-flow state, positron emission tomography and dobutamine stress echocardiography were performed to document ischemic, viable (hibernating) myocardium in the left circumflex distribution. Animals then had sham redo thoracotomy (n = 4) or TMR (n = 6). Six months later the positron emission tomography and dobutamine stress echocardiography studies were repeated.

Results. Myocardial blood flow in the left circumflex distribution as measured by positron emission tomography was significantly reduced in all animals after 2 weeks in the low-flow state. In animals that had TMR, there was significant improvement in myocardial blood flow to the lased regions 6 months postoperatively. No significant change in myocardial blood flow was seen in sham animals at 6 months. Dobutamine stress echocardiography after 2 weeks of low-flow demonstrated severe hypocontractility at rest in the left circumflex region of all animals, with a biphasic response to dobutamine consistent with hibernating myocardium. In animals that had TMR, there was a trend toward improved resting function and significantly improved regional stress function in the lased segments 6 months postoperatively, consistent with a reduction in ischemia. Global left ventricular wall motion at peak stress improved significantly as well. There was no change in wall motion 6 months postoperatively in sham-operated animals.

Conclusions. This study found improvements in myocardial perfusion and regional and global contractile reserve 6 months after TMR in a porcine model of hibernating myocardium. This improved perfusion and function likely accounts for the clinical benefits of the procedure.  相似文献   

85.
ObjectivesTo investigate the relationship between sport injury and body mass index in adolescents (12–19 years).DesignSecondary analysis of data collected in junior and senior high school surveys in Alberta, Canada.MethodsParticipants (n = 4339) included students from 59 schools. All sport injury was defined as injury reported in the past one year. Medically treated injury, as any more serious sport related injury reported in the last year that required medical attention. Overweight, obese, and healthy was defined using international cut points, as the exposure.ResultsMultivariate logistic regression analysis controlling for clustering by school, and adjusting for potential risk factors was used. There was a 34% increased risk for all sport injury in obese adolescents compared to healthy adolescents [odds ratio (OR) = 1.34 (95% CI: 1.02–1.80)]. There was increased risk for all sport injury and medically treated injury with hours of participation, where the highest group had a 4-fold increase in risk (OR = 4.17, 95%CI: 2.77–6.30 and OR = 3.80, 95%CI: 2.54–5.69, respectively). There was also increased risk for both all sport injury and medically treated injury in Caucasians compared to non-Caucasians [OR = 1.45 (95%CI: 1.15–1.82), OR = 1.94 (95%CI: 1.59–2.37), respectively], as well as for club/team play compared to less elite play [OR = 1.87 (95%CI: 1.43–2.44) and OR = 2.12 (95%CI: 1.57–2.87), respectively].ConclusionsThe risk of sustaining a sport injury in obese adolescents was greater compared to those of healthy weight. There is also a greater risk with increasing hours of play, in Caucasian adolescents, and those that play at a higher sporting level.  相似文献   
86.
BackgroundProspectively triggered coronary computed tomography angiography (CTA) is commonly performed with a widened acquisition window to provide flexibility in image reconstruction.ObjectiveWe conducted a randomized controlled trial to determine whether the use of a narrow acquisition window in prospectively triggered coronary CTA would allow lower radiation dose while preserving image quality and interpretability.MethodsProspective 2-center 2- platform randomized trial that evaluated 205 consecutive patients 96 with widened acquisition (WA) and 109 narrow acquisition (NA) referred for coronary CTA in sinus rhythm and heart rate <65 beats/min. Patients scanned with WA had phases reconstructed at 5% intervals, and each phase was assigned an individual study ID. Images were reviewed with individual phase reconstructions interpreted randomly by 2 level 3 readers with a third for consensus. Images were evaluated with a 5-point Likert scale on a per-vessel basis (best score on any phase). Scores were then dichotomized into diagnostic (score 3–5) compared with nondiagnostic (score 1–2). Readers also reported obstructive coronary artery disease on a per-patient basis. Agreement for the diagnosis of obstructive disease and per-artery interpretability was performed. Signal and noise measurements were also performed.ResultsNo difference in demographics between groups (P = NS). The signal-to-noise ratio was comparable 12.99 ± 3.4 NA and 12.53 ± 4.13 for the WA (P = 0.45). The median effective dose was 1.78 mSv for NA compared with 3.26 mSv for WA (P < 0.001). Image quality, diagnostic interpretability, interreader agreement, and downstream testing were not significantly different between the 2 groups (P= NS for all).ConclusionsCoronary CTA with NA resulted in a 47% lower radiation dose without significant difference in study interpretability or image quality or increased downstream resource use or testing.  相似文献   
87.
Treatment of chronic kidney disease (CKD) can slow its progression to end-stage renal disease (ESRD). However, the therapies remain limited. Blood pressure control using angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) has the greatest weight of evidence. Glycemic control in diabetes seems likely to retard progression. Several metabolic disturbances of CKD may prove to be useful therapeutic targets but have been insufficiently tested. These include acidosis, hyperphosphatemia, and vitamin D deficiency. Drugs aimed at other potentially damaging systems and processes, including endothelin, fibrosis, oxidation, and advanced glycation end products, are at various stages of development. In addition to the paucity of proven effective therapies, the incomplete application of existing treatments, the education of patients about their disease, and the transition to ESRD care remain major practical barriers to better outcomes.  相似文献   
88.

BACKGROUND:

The common peroneal nerve is the most commonly injured nerve in the lower limb. Nerve transfer using expendable donor nerves is emerging in the literature as an alternative surgical procedure to traditional treatments.

OBJECTIVE:

To identify potential donors of motor axons from the tibial nerve that can be transferred to the common peroneal nerve branches.

METHODS:

Using 10 human cadaveric lower extremities, all motor nerve branches of the tibial nerve were identified and biopsied. These were compared with the motor branches to tibialis anterior and extensor hallucis longus (branches of the deep peroneal nerve).

RESULTS:

The most suitable donor nerves with respect to cross-sectional area to tibialis anterior (cross sectional area [mean ± SD] 0.255±0.111 mm) was the motor branch to lateral gastrocnemius (0.256±0.105 mm). When comparing the total number of axons, the branch to the tibialis anterior had a mean of 3363±1997 axons. The branch to the popliteus was most similar, with 3317±1467 axons. The most suitable donor nerves for the motor branch to extensor hallucis longus (cross sectional area 0.197±0.302 mm) with respect to cross-sectional area was the motor branch to flexor hallucis longus (0.234±0.147 mm). When comparing the total number of axons, the branch to the extensor hallucis longus had an average of 2062±2314 axons. The branch to the lateral gastrocnemius was most similar with 2352±1249 axons and was a suitable donor.

CONCLUSION:

Nerve transfers should be included in the armamentarium for lower extremity reinnervation, as it is in the upper limb.  相似文献   
89.
Background Nonsurgical assessment of sentinel nodes (SNs) would offer advantages over surgical SN excision by reducing morbidity and costs. Proton magnetic resonance spectroscopy (MRS) of fine-needle aspirate biopsy (FNAB) specimens identifies melanoma lymph node metastases. This study was undertaken to determine the accuracy of the MRS method and thereby establish a basis for the future development of a nonsurgical technique for assessing SNs. Methods FNAB samples were obtained from 118 biopsy specimens from 77 patients during SN biopsy and regional lymphadenectomy. The specimens were histologically evaluated and correlated with MRS data. Histopathologic analysis established that 56 specimens contained metastatic melanoma and that 62 specimens were benign. A linear discriminant analysis–based classifier was developed for benign tissues and metastases. Results The presence of metastatic melanoma in lymph nodes was predicted with a sensitivity of 92.9%, a specificity of 90.3%, and an accuracy of 91.5% in a primary data set. In a second data set that used FNAB samples separate from the original tissue samples, melanoma metastases were predicted with a sensitivity of 87.5%, a specificity of 90.3%, and an accuracy of 89.1%, thus supporting the reproducibility of the method. Conclusions Proton MRS of FNAB samples may provide a robust and accurate diagnosis of metastatic disease in the regional lymph nodes of melanoma patients. These data indicate the potential for SN staging of melanoma without surgical biopsy and histopathological evaluation.  相似文献   
90.
Background: Many studies have shown in the efficacy of patient-controlled analgesia (PCA). However, it is not clear whether PCA has clinical or economic benefits in addition to efficient analgesia. The current study was designed to evaluate these issues by comparing PCA with regularly administered intramuscular injections of opioids after hysterectomy.

Methods: This prospective study included 126 patients who underwent abdominal hysterectomy and were randomly assigned to receive PCA or regularly timed intramuscular injections of morphine during a period of 48 h. Doses were adjusted to provide satisfactory analgesia in both treatment groups. Pain at rest and with movement, functional recovery, drug side effects, and patient satisfactory were measured using rating scales and questionnaires. The costs of PCA and intramuscular therapy were calculated based on personnel time and drug and material requirements.

Results: Comparable analgesia was observed with the two treatment methods, with no significant differences in the incidence of side effects or patient satisfaction. The medication dosage had to be adjusted significantly more frequently in the intramuscular group than in the PCA patients. The PCA did not favor a faster recuperation time compared with intramuscular therapy in terms of times of ambulation, resumption of liquid and solid diet, passage of bowel gas, or hospital discharge. The results of the economic evaluation, which used a cost-minimization model and sensitivity analyses, showed that PCA was more costly than regular intramuscular injections despite the fact that no costs for the pump were included in the analyses. Cost differences in nursing time favoring PCA were offset by drug and material costs associated with this type of treatment.  相似文献   

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