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41.
Brandt MM Wahl WL Yeom K Kazerooni E Wang SC 《The Journal of trauma》2004,56(5):1022-6; discussion 1026-8
BACKGROUND: We hypothesize that data collected from computed tomographic (CT) scans obtained for workup of chest or abdominal injuries provide data that are sufficient to screen for spinal fractures and will decrease the cost and time of spine evaluation after trauma. METHODS: We reviewed plain radiographs from 55 selected trauma patients who also underwent CT scanning of the chest, abdomen, and pelvis. We also timed the radiologic workup of 50 consecutive trauma patients to determine the time required to complete radiographic spine evaluation. RESULTS: Forty-seven patients had thoracolumbar fractures. Thirteen patients were found to have 33 thoracolumbar spine fractures identified by CT scan but not plain radiography. Fractures were found on initial trauma CT scans of the chest, abdomen, and pelvis obtained to evaluate for visceral injuries. No injuries seen on plain film were missed on CT scan. CONCLUSION: We recommend using the data acquired from CT scans to evaluate the spine, supplementing them with additional studies only when needed for further clarification. 相似文献
42.
A new X-ray tube with a less than 10 microns microfocus enables investigations supported by direct radiological magnification. It allows the nondestructive examination of mineralized structures up to microscopic dimensions. For experimental research on bony tissue, teeth and in the field of dental material science, new and interesting areas have been opened. Examples demonstrate possibilities of this special radiographic method. 相似文献
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R H Knopp R O Bergelin P W Wahl C E Walden 《Metabolism: clinical and experimental》1985,34(10):893-899
Lipoprotein cholesterol/triglyceride ratio changes have been observed previously with sex hormone use. To determine if the lipoprotein cholesterol/triglyceride ratio is similarly changed by pregnancy and postpartum lactation, we examined pregnant subjects at 36 weeks gestation and the same women at 6 weeks postpartum and compared them to age-matched, nonpregnant women using or not using oral contraceptives. The cholesterol/triglyceride ratios were examined as means and medians and as curvilinear functions of increasing triglyceride concentration. Median ratios did not predict all ratio changes identified graphically. At very-low-density lipoprotein (VLDL) triglyceride concentrations below 40 mg/dL, the VLDL ratio is less than control in oral contraceptive users and further reduced in pregnant women. Above triglyceride concentrations of 40-60 mg/dL, the curves in the three groups are indistinguishable. No effect of lactation is observed. The low-density lipoprotein (LDL) cholesterol/triglyceride ratio is comparably lower in pregnant subjects and oral contraceptive users at all concentrations of lipoprotein triglyceride and again there is no effect of lactation. In high-density lipoprotein (HDL), there is no effect of either pregnancy or oral contraceptive use on the cholesterol/triglyceride ratio, while it is significantly higher with lactation. Postpartum decreases in the VLDL and LDL cholesterol/triglyceride ratio are seen at all lipoprotein concentrations independent of lactation. We conclude that triglyceride enriches VLDL at low concentrations and LDL at all concentrations in pregnancy and with oral contraceptive use, suggesting a common, hormonal mechanism. HDL is enriched with cholesterol during postpartum lactation, consistent with decreased transfer of cholesterol to other lipoproteins.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
47.
This study examines the scintigraphic features of patients in Killip class I or II after acute myocardial infarction (AMI) with relation to ECG changes. The 41 consecutively studied patients (23 men and 18 women) with first AMI were divided into two groups: group 1 (n = 25) had Q wave AMI, and group 2 (n = 16) had non-Q wave AMI. Rest thallium-201 myocardial scintigrams and radionuclide ventriculograms were obtained 10 days (mean) after AMI. The thallium images were divided into 15 segments in three projections and assessed qualitatively and quantitatively. Fixed perfusion defects were present in at least one segment in 23 patients (92%) in group 1 and in eight patients (50%) in group 2 (p = 0.007). All but one patient in group 1 (4%) and three patients in group 2 (19%) had perfusion defects (fixed or reversible). The number of segments with perfusion defects was 5.6 +/- 2.6 in group 1 and 2.9 +/- 2.3 in group 2 (p = 0.002); the peak creatine kinase was 1280 +/- 880 Units/L in group 1 and 360 +/- 340 Units/L in group 2 (p less than 0.001); the left ventricular ejection fraction was 38 +/- 14% in group 1 vs 43 +/- 15% in group 2 (p = NS). Thus fixed perfusion defects are present in 92% of patients with Q waves and in 50% of patients with no Q waves. 相似文献
48.
Background: Jejunoileal (JI) bypass was a widely performed operation for morbid obesity in the 1970s.The aim of this study
was to investigate the long-term status for mental and physical health after weight loss induced by this operation. Methods:
20 female patients (age 48-80 y, BMI 23-75 kg/m2) were interviewed 25 years after JI bypass. The Hospital Anxiety and Depression Scale (HAD) and Short Form 36 (SF-36) were
used. Scores from the Norwegian female population, and published scores for morbidly obese patients were used for comparison.
An assessment was made on whether present demographic and clinical factors influenced the scores. Results: Anxiety and depression
scores, and scores for physical functioning, bodily pain, vitality and mental health on the SF-36 were similar to scores in
the Norwegian female population used for comparison. The scores from the patient sample were much better than scores published
for morbidly obese patients, and implies that weight loss induced by the operation has been of great benefit on mental health
and health-related quality of life. Anxiety and depression symptoms improved; however, being socially handicapped by the stools
had a negative impact on HAD and SF-36 scores. Conclusion: These results suggest that 25 years after the JI bypass most of
these patients have a similar level of mental and physical health as the general Norwegian female population. For individuals
with bothersome side-effect(s) of the operation, a negative impact is seen. 相似文献
49.
外科医生和手术室人员经常接触手术设备产生的烟气,病人也会暴露于烟气中,特别是腹腔镜手术中产生的烟气滞留于腹腔内这一密闭空间并被吸收.这些烟气是一种与香烟烟气相似的毒性物质,然而对这种毒性物质的影响还未引起足够重视.应该采取必要措施尽可能减少手术中烟气的不良影响. 相似文献
50.
Head‐locking durability of fixed and variable angle locking screws under repetitive loading 下载免费PDF全文
Mark Lenz Dieter Wahl Ivan Zderic Boyko Gueorguiev Jesse B. Jupiter Stephan M. Perren 《Journal of orthopaedic research》2016,34(6):949-952
Polyaxial locking screws are increasingly applied in fracture fixation. To investigate the durability of the head‐locking mechanism, the removal torque of variable angle (VA) and fixed angle (FA) stainless steel and titanium locking screws was investigated without and after a cyclic loading test. Stainless steel (St) and titanium (Ti) 2.4 mm orthogonally inserted FA screws and 2.4 mm VA screws inserted in different inclinations (0°–15°) (n = 6 per group) were locked at 0.8 Nm. Removal torque was determined without (W) and after (A) cyclic loading (sinusoidal load, 5 Hz, constant amplitude of 25 N, up to 10′000 cycles, or failure). Significant differences in‐between the groups were detected by Student's t‐test (p < 0.05). Except VA Ti in 0deg and FA, all groups exhibited a drop in removal torque below the insertion torque without and after cyclic testing. The removal torque was (St: FA W:0.81 Nm ± 0.04 A:0.72Nm ± 0.04; VA0deg W:0.73 Nm ± 0.04 A:0.65 Nm ± 0.05; VA15deg W:0.51 Nm ± 0.05 A:0.50 Nm ± 0.08; Ti: FA W:0.82 Nm ± 0.03 A:0.70 Nm ± 0.04; VA0deg W:0.80 Nm ± 0.02 A:0.72 Nm ± 0.05; VA15deg W:0.55 Nm ± 0.03 A:0.54 Nm ± 0.06). In all groups, the removal torque after cyclic testing did not drop below 16% of the removal torque without cyclic testing. No head loosening was observed after cyclic testing. Stainless steel and titanium 2.4 mm fixed and variable angle locking screws provide a stable and lasting head‐locking mechanism. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:949–952, 2016. 相似文献