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71.
The prevailing emphasis on adopting evidence-based practices suggests that more focused training evaluations that capture factors in clinician decisions to use new techniques are needed. This includes relationships between postconference evaluations and subsequent adoption of training materials. We therefore collected training assessments at two time points from substance abuse treatment counselors who attended a training on dual diagnosis and another on therapeutic alliance as part of a state-sponsored conference. Customized evaluations were collected to assess counselor perceptions of training quality, relevance, and resources in relation to its use during the 6 months after the conference. Higher ratings for relevance of training concepts and materials to service the needs of clients, desire to have additional training, and level of program support were related to greater trial use during the follow-up period. Primary resource-related and procedural barriers cited by the counselors included lack of time and redundancy with existing practices.  相似文献   
72.
Diagnosis of acute abdominal pain in older patients   总被引:5,自引:0,他引:5  
Acute abdominal pain is a common presenting complaint in older patients. Presentation may differ from that of the younger patient and is often complicated by coexistent disease, delays in presentation, and physical and social barriers. The physical examination can be misleadingly benign, even with catastrophic conditions such as abdominal aortic aneurysm rupture and mesenteric ischemia. Changes that occur in the biliary system because of aging make older patients vulnerable to acute cholecystitis, the most common indication for surgery in this population. In older patients with appendicitis, the initial diagnosis is correct only one half of the time, and there are increased rates of perforation and mortality when compared with younger patients. Medication use, gallstones, and alcohol use increase the risk of pancreatitis, and advanced age is an indicator of poor prognosis for this disease. Diverticulitis is a common cause of abdominal pain in the older patient; in appropriately selected patients, it may be treated on an outpatient basis with oral antibiotics. Small and large bowel obstructions, usually caused by adhesive disease or malignancy, are more common in the aged and often require surgery. Morbidity and mortality among older patients presenting with acute abdominal pain are high, and these patients often require hospitalization with prompt surgical consultation.  相似文献   
73.
We developed a pulmonary graphic display that depicts pulmonary physiological variables for intubated, mechanically ventilated patients in a graphical format. The pulmonary graphical display presents multiple respiratory variables and changes are depicted by alterations in shape and color. Learning how this new technology will be integrated and accepted by users is an important step before it is introduced into the clinical arena. This study observed use and acceptance of the pulmonary graphical display by health care providers in an intensive care unit. Investigators noted that physicians, respiratory therapists, and nurses observed the pulmonary graphical display on average six, three, and one times, respectively, per patient room entry. Based on questionnaires, the pulmonary graphical display was perceived as useful, a desirable addition to current ICU monitors, and an accurate representation of respiratory variables.  相似文献   
74.

Background

This article provides a review of the current state of laser-assisted keratoplasty and describes a first proof of concept study to test the feasibility of a new mid-infrared (MIR) picosecond laser to perform applanation-free corneal trephination.

Methods

The procedure is based on a specially adapted laser system (PIRL-HP2-1064 OPA-3000, Attodyne, Canada) which works with a wavelength of 3,000?±?90 nm, a pulse duration of 300 ps and a repetition rate of 1 kHz. The picosecond infrared laser (PIRL) beam is delivered to the sample by a custom-made optics system with an implemented scanning mechanism. Corneal specimens were mounted on an artificial anterior chamber and subsequent trephination was performed with the PIRL under stable intraocular pressure conditions.

Results

A defined corneal ablation pattern, e.g. circular, linear, rectangular or disc-shaped, can be selected and its specific dimensions are defined by the user. Circular and linear ablation patterns were employed for the incisions in this study. Linear and circular penetrating PIRL incisions were examined by macroscopic inspection, histology, confocal microscopy and environmental scanning electron microscopy (ESEM) for characterization of the incisional quality. Using PIRL reproducible and stable incisions could be made in human and porcine corneal samples with minimal damage to the surrounding tissue.

Conclusion

The PIRL laser radiation in the mid-infrared spectrum with a wavelength of 3 µm is exactly tuned to one of the dominant vibrational excitation bands of the water molecule, serves as an effective tool for applanation-free corneal incision and might broaden the armamentarium of corneal transplant surgery.  相似文献   
75.
Vascular networks develop from a growing vascular front that responds to VEGF and other guidance cues. Angiogenesis is required for normal tissue function, but, under conditions of stress, inappropriate vascularization can lead to disease. Therefore, inhibition of angiogenic sprouting may prevent neovascularization in patients with blinding neovascular eye diseases, including macular degeneration. VEGF antagonists have therapeutic benefits but also can elicit off-target effects. Here, we found that the Ras pathway, which functions downstream of a wide range of cytokines including VEGF, is active in the growing vascular front of developing and pathological vascular networks. The endogenous Ras inhibitor p120RasGAP was expressed predominately in quiescent VEGF-insensitive endothelial cells and was ectopically downregulated in multiple neovascular models. MicroRNA-132 negatively regulated p120RasGAP expression. Experimental delivery of α-miR-132 to developing mouse eyes disrupted tip cell Ras activity and prevented angiogenic sprouting. This strategy prevented ocular neovascularization in multiple rodent models even more potently than the VEGF antagonist, VEGF-trap. Targeting microRNA-132 as a therapeutic strategy may prove useful for treating multiple neovascular diseases of the eye and for preventing vision loss regardless of the neovascular stimulus.  相似文献   
76.
77.
Prospective studies analyzing the ThinPrep Imaging System (TIS) have demonstrated a significant decrease in screening time and detection rates comparable or better than manual screening. We retrospectively analyzed the accuracy of the TIS in detecting cervical abnormalities. Our study included all new HSIL diagnoses in 2007 with previous negative (NIL) pap tests screened with TIS. The original 22 fields of view (FOV) were reviewed by 2 blinded screeners followed by manual screening of all slides. Any ASC-US or above was considered "abnormal." Of a total of 111,080 pap tests performed in 2007, 180 were reported as HSIL. Of these, 45 cases had a previous NIL pap diagnosed within the last year, screened with TIS. Following re-examination of the NIL pap, 31 diagnoses remained unchanged and 9 were reclassified as abnormal on the basis of cells present within the original FOV. When manually reviewed, all nine cases were confirmed as abnormal. Four cases were reclassified as abnormal on the basis of the manual screen (abnormal cells absent in the FOV). The sensitivity of TIS for the detection of abnormality was 99.95% (false-negative rate FNR: 0.05%) and the sensitivity for detection of HSIL was 99.07% (FNR: 0.92%). When analyzing the cytotechnologist interpretation of the FOV, the sensitivity for detection of abnormality and HSIL was 99.89% (FNR: 0.1%), and 99.53% (FNR: 0.4%), respectively. On retrospective analysis based on newly diagnosed HSIL cases, the sensitivity of TIS was comparable to that of manual screening with a slightly decreased rate of false negatives.  相似文献   
78.
A 40-year-old woman underwent excision of a painless left vulvar mass. The specimen showed a well-circumscribed mass measuring 3.5 × 2.7 × 2.5 cm. Microscopic examination exhibited an encapsulated neoplasm with a solid and papillary growth pattern. The tumor cells were oval to columnar and showed moderate nuclear atypia. No capsular invasion was identified. Immunonegativity for calponin and p63 confirmed the absence of myoepithelial cells either within or at the periphery of the tumor. The tumor was immunopositive for gross cystic disease fluid protein 15, synaptophysin, and chromogranin. The histologic and immunohistochemical characteristics were consistent with an encapsulated solid papillary carcinoma with neuroendocrine differentiation. The patient has been free of disease for 4 years after surgery. This is the first report of a vulvar encapsulated solid papillary carcinoma with neuroendocrine differentiation. Correct diagnosis is imperative because of the distinct biologic behavior of the tumor.  相似文献   
79.
Accurate quantification of circulating cell populations in mice is important in many areas of preclinical biomedical research. Normally, this is done either by extraction and analysis of small blood samples or, more recently, by using microscopy-based in vivo fluorescence flow cytometry. We describe a new technological approach to this problem using detection of diffuse fluorescent light from relatively large blood vessels in vivo. The diffuse fluorescence flow cytometer (DFFC) uses a laser to illuminate a mouse limb and an array of optical fibers coupled to a high-sensitivity photomultiplier tube array operating in photon counting mode to detect weak fluorescence signals from cells. We first demonstrate that the DFFC instrument is capable of detecting fluorescent microspheres and Vybrant-DiD-labeled cells in a custom-made optical flow phantom with similar size, optical properties, linear flow rates, and autofluorescence as a mouse limb. We also present preliminary data demonstrating that the DFFC is capable of detecting circulating cells in nude mice in vivo. In principle, this device would allow interrogation of the whole blood volume of a mouse in minutes, with sensitivity improvement by several orders of magnitude compared to current approaches.  相似文献   
80.

Introduction

Fluid strategies may impact on patient outcomes in major elective surgery. We aimed to study the effectiveness and cost-effectiveness of pre-operative fluid loading in high-risk surgical patients undergoing major elective surgery.

Methods

This was a pragmatic, non-blinded, multi-centre, randomised, controlled trial. We sought to recruit 128 consecutive high-risk surgical patients undergoing major abdominal surgery. The patients underwent pre-operative fluid loading with 25 ml/kg of Ringer's solution in the six hours before surgery. The control group had no pre-operative fluid loading. The primary outcome was the number of hospital days after surgery with cost-effectiveness as a secondary outcome.

Results

A total of 111 patients were recruited within the study time frame in agreement with the funder. The median pre-operative fluid loading volume was 1,875 ml (IQR 1,375 to 2,025) in the fluid group compared to 0 (IQR 0 to 0) in controls with days in hospital after surgery 12.2 (SD 11.5) days compared to 17.4 (SD 20.0) and an adjusted mean difference of 5.5 days (median 2.2 days; 95% CI -0.44 to 11.44; P = 0.07). There was a reduction in adverse events in the fluid intervention group (P = 0.048) and no increase in fluid based complications. The intervention was less costly and more effective (adjusted average cost saving: £2,047; adjusted average gain in benefit: 0.0431 quality adjusted life year (QALY)) and has a high probability of being cost-effective.

Conclusions

Pre-operative intravenous fluid loading leads to a non-significant reduction in hospital length of stay after high-risk major surgery and is likely to be cost-effective. Confirmatory work is required to determine whether these effects are reproducible, and to confirm whether this simple intervention could allow more cost-effective delivery of care.

Trial registration

Prospective Clinical Trials, ISRCTN32188676  相似文献   
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