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21.
22.
To evaluate the effects of calcium entry blocking agents on cardiac sympathetic tone during angina pectoris, arterial and coronary sinus (CS) norepinephrine (NE) and epinephrine (E) concentrations and CS blood flow were determined at rest and during pacing-induced angina, both before and after verapamil in nine patients and after nifedipine in nine patients, all of whom had fixed obstructive coronary artery disease. Resting arterial NE and E concentrations and myocardial NE release and E uptake remained unchanged during angina before verapamil and nifedipine, suggesting unaltered systemic and cardiac sympathetic tone and myocardial E handling. Following verapamil and nifedipine, arterial NE and E concentrations remained unchanged. After verapamil, net myocardial NE release increased from 16,072 +/- 18,881 to 35,520 +/- 30,595 at preverapamil angina rate (p less than 0.01) and to 39,643 +/- 29,728 pg/min at postverapamil angina rate (p less than 0.01). NE release after nifedipine increased from -4207 +/- 8898 to 10,988 +/- 30,711 (p less than 0.05) at prenifedipine angina rate and to 19,942 +/- 26,644 pg/min (p less than 0.05) at postnifedipine angina rate. NE release was independent of changes in CS flow after verapamil or nifedipine. E uptake after verapamil and nifedipine remained unchanged. Although the precise mechanism is not known, myocardial alpha-adrenergic receptor blockage with verapamil and nifedipine remains a possible explanation for increased myocardial NE release.  相似文献   
23.
Out of 25 cases of trophic ulcers of the foot, 10 (40%) were both aerobic and anaerobic, 14 (56%) only aerobic and one (4%) showed no growth of bacteria. With the exception of two cases (8%) in the aerobic group, all others showed mixed infections. A wide range of bacteria is reported. Topical application of gentamicin and chloramphenicol is recommended, based on the results of in vitro sensitivity.  相似文献   
24.
Surgical drains are commonly used in plastic surgery. Drains are subsequently removed at arbitrary volumes depending on local protocols. The rational for when to remove a drain has not been scientifically determined. We compared removal of drains at ≤30?ml/24?h vs. ≤50?ml/24?h for 158 wounds, in 90 patients. Postoperative complications, length of hospital stay and resulting cost–benefit were considered. Prospective data were collected for two consecutive similar cohorts of patients undergoing abdominoplasty, bilateral breast reduction and breast augmentation. In the first cohort, drains were removed when drainage was ≤30?ml/24?h and the second cohort when ≤50?ml/24?h. Demographics, days of drainage, surgeon grade and duration of postoperative hospital stay were recorded. Patient records were then analysed and complications recorded, including haematoma, infection, seroma, wound breakdown and fat necrosis. The median postoperative stay for all three operations for both drainage cohorts was similar with no statistically significant difference; however, the drainage time in breast augmentation was significantly less in the <50?ml/24?h group. There were no significant differences in outcome measures between the patients undergoing abdominoplasty, breast reduction or breast augmentation. Drain removal at ≤50 vs. ≤30?ml/24?h did not result in an increase in postoperative morbidity or adverse outcome in any of the three different operation types.  相似文献   
25.

Backgrounds

Cost-effectiveness analysis plays an important role to guide resource allocation decisions, however, information on cost per disability-adjusted life year (DALY) averted by health facilities is not available in many developing economies, including India. We estimated cost per DALY averted for 2611 patients admitted for surgical interventions in a 106-bed private for-profit hospital in northern India.

Methods

Costs were calculated using standard costing methods for the financial year 2012–2013, and effectiveness was measured in DALYs averted using risk of death/disability, effectiveness of treatment and disability weights from 2010 global burden of disease study.

Results

During the study period, total operating cost of the hospital for treating surgical patients was USD 1,554,406 and the hospital averted 9401 DALYs resulting in a cost per DALY averted of USD 165.

Conclusions

Even though this study was based on one hospital in India, however, the hospital is a private hospital which is expected to have less surgical case load compared to government health facilities, cost per DALY averted for the surgical interventions is much lower than the cost-effectiveness threshold for India (USD 1508 in 2012). This study therefore provides evidence to re-think the common notion that surgical care is expensive and therefore of lower value than other health interventions.
  相似文献   
26.

Background

Performing a laparoscopic urethrovesical anastomosis (LUA) after a radical prostatectomy is technically challenging for the novice laparoscopic surgeon. We developed a low-fidelity urethrovesical model (UVM) to allow a urologist to practise this critical step. The aim of our study was to compare the effect of task-specific bench model training (anastomotic suturing on the UVM) with that of basic laparoscopic suturing on intracorporeal urethrovesical anastomosis performance.

Methods

We recruited 28 senior surgical residents, fellows or staff surgeons for this prospective, single-blinded, randomized controlled study. We randomly assigned participants to an intervention group practising LUA on the UVM or to a control group practising basic laparoscopic suturing and knot-tying on a foam pad. After practising, we videotaped participants performing 5 intra-corporeal interrupted sutures on a foam pad and a LUA on the UVM. A blinded expert scored the videotaped performance using a laparoscopic suturing checklist (CL) and a global rating scale (GRS), and timed the performance.

Results

On the foam pad suturing task, the group that trained on the UVM had significantly higher CL scores (10.9 v. 8.1, p = 0.017). On the LUA task, the group that trained on the UVM had significantly higher CL scores (10.9 v. 8.1, p = 0.017), GRS (29.6 v. 22.8, p = 0.005) and shorter times (27.6 v. 38.3 min, p = 0.004) than the control group.

Conclusion

Our task-specific bench model was shown to be superior to basic laparoscopic suturing drills on a foam pad.  相似文献   
27.
OBJECTIVE: To assess whether central corneal thickness (CCT) is a confounding factor in the classification of patients attending for glaucoma assessment in a district general hospital. DESIGN: Cross-sectional study by a single observer. PARTICIPANTS: Patients attending a general ophthalmic clinic: 235 clinically normal eyes, 52 eyes with normal-tension glaucoma (NTG), 335 eyes with primary open-angle glaucoma (POAG), 12 eyes with pseudoexfoliative glaucoma (PXE), 42 eyes with chronic angle closure glaucoma (CACG), and 232 glaucoma suspect (GS) eyes. INTERVENTION: Central corneal thickness was measured using ultrasonic pachymetry. MAIN OUTCOME MEASURE: Correlation of CCT and diagnosis. RESULTS: Mean CCT was 553.9 microm (95% confidence intervals [CI] for the mean, 549.0-558.8 microm) in the clinically normal eyes, 550.1 microm (95% CI, 546.6-553.7 microm) in the POAG eyes, 514.0 microm (95% CI, 504.8-523.3 microm) in the NTG eyes, 530.7 microm (95% CI, 511.2-550.1 microm) in the PXE eyes, 559.9 microm (95% CI, 546.8-573.0 microm) in the CACG eyes, and 579.5 microm (95% CI, 574.8-584.1 microm) in the GS eyes. The differences of mean CCT between the groups were highly significant (P< 0.001 analysis of variance). Eighty-five percent of eyes with NTG and only 36% of eyes with POAG had a mean CCT of 540 microm or less. Thirteen percent of eyes with POAG and 42% of GS eyes had a mean CCT greater than 585 microm. CONCLUSIONS: The CCT measurement is desirable in patients attending for glaucoma assessment in a district general hospital to avoid misclassification resulting from the relationship between CCT and tonometric pressure. Central corneal thickness alone is not an accurate predictor for the clinical diagnosis in this group of eyes. However, many eyes diagnosed as having NTG have thin corneas, which would tend to lower the tonometrically recorded intraocular pressure (IOP), so the finding of a less-than-normal thickness cornea introduces some doubt as to the diagnosis of NTG. For the GS eyes, most eyes had thick corneas, which would tend to increase the tonometrically recorded IOP. Thus, GS eyes with modest elevation of IOP and a thick cornea may be at low risk of progressing to POAG. Thus, many patients with "high IOPs" and a thick CCT do not necessarily have high IOPs and may not need to be followed as GS eyes.  相似文献   
28.
Albino hairless mice (Skh:HR-1) exposed chronically to suberythemal doses of ultraviolet radiation develop visible skin changes, histological alterations, and tumors. Topical treatment of mice with solutions of superoxide-scavenging antioxidants (such as alpha-tocopherol, ascorbic acid, propyl gallate and Trolox) prior to each UVB radiation exposure reduced significantly the severity of these events. Tocopherol esters and ascorbyl palmitate were not as effective as the parent compounds in providing protection. The data suggest a role for superoxide in UVB radiation-induced skin photoaging and the protective potential of superoxide scavengers. In contrast, the severity of UVA radiation-induced mouse skin damage was not reduced by topical application of the antioxidants tested here.  相似文献   
29.
Contactins are a group of cell adhesion molecules that are mainly expressed in the brain and play pivotal roles in the organization of axonal domains, axonal guidance, neuritogenesis, neuronal development, synapse formation and plasticity, axo-glia interactions and neural regeneration. Contactins comprise a family of six members. Their absence leads to malformed axons and impaired nerve conduction. Contactin mediated protein complex formation is critical for the organization of the axon in early central nervous system development. Mutations and differential expression of contactins have been identified in neuro-developmental or neurological disorders. Taken together, contactins are extensively studied in the context of nervous system development. This review summarizes the physiological roles of all six members of the Contactin family in neurodevelopment as well as their involvement in neurological/neurodevelopmental disorders.  相似文献   
30.
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