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131.
PURPOSE: We describe a technique for correction of proximal interphalangeal joint (PIP) extensor lag secondary to angulation and/or shortening of proximal phalanx fractures. METHODS: Proximal phalanx fracture malunions with 2.5 mm of shortening, 5.0 mm of shortening, and apex volar angulation of 40 degrees were simulated in 15 cadaver fingers, creating PIP extensor lags. The metacarpophalangeal (MCP) joint was pinned in neutral. Transection of the ulnar and radial sagittal bands, the extensor digitorum communis (EDC) insertion on the MCP joint capsule, and the juncturae tendinae then was performed. The PIP extensor lag before and after each of the earlier-noted releases was recorded. The MCP joint then was freed and MCP hyperextension was recorded. With the MCP joint in neutral position the sagittal bands then were reapproximated with sutures and MCP extension was measured. RESULTS: The 2.5 mm of axial shortening, 5.0 mm of axial shortening, and 40 degrees of apex volar angulation fracture models produced an average extensor lag of 6.2 degrees , 25.8 degrees , and 42.5 degrees , respectively. Maximal correction of PIP extensor lag required transection of both sagittal bands, EDC insertion on the MCP capsule, and the juncturae tendinae with an average residual extensor lag of -0.8 degrees for the 2.5-mm shortening model, 0.7 degrees for the 5.0-mm shortening model, and 3.2 degrees for the 40 degrees -angulation model. The MCP joint hyperextension increased by 20 degrees to 30 degrees after the releases but decreased to only 1.8 degrees if the sagittal bands were reapproximated to the EDC tendon at their new resting position with the MCP joint in neutral position. CONCLUSIONS: In the cadaver model the PIP extensor lag can be improved substantially by transection of the sagittal bands, release of the EDC insertion on the MCP capsule, transection of the juncturae tendinae, and reapproximation of the sagittal bands to the EDC tendon.  相似文献   
132.
ObjectivesMeasuring the neck-shaft angle (NSA) and amount of shortening of the femoral neck on the anterior to posterior (AP) X-ray is important when treating proximal femur fractures. To compensate for proximal femoral external rotation, the X-rays need to be taken with the leg internally rotated, an act that cannot always be performed or verified. This study aims to define the utility of in situ AP X-ray in NSA and shortening measurements.MethodsComputed tomography (CT) scans of 50 patients undergoing abdominal CT scans were assessed for the in situ rotation of the femoral neck relative to the AP beam. Three proximal femur fracture Sawbones models were made and AP X-rays of the models were taken with changing proximal femur rotation. NSA and shortening were measured on all X-rays.ResultsIn situ femoral neck rotation averaged 25.4 ± 10.6° of external rotation (range, 0.9–51.8°, 80% of measurements less than 35°). NSA measurements varied less than 5° with less than 35° of rotation in all models, and were always greater than the true value. Femoral neck vertical length (VL) measurement was independent of proximal femur rotation whereas the horizontal length component was found to be highly dependent on the same.ConclusionsNSA measured on AP X-ray will be accurate to within 5° in 80% of patients with the hip left in situ and in 100% of the patients if the hip is internally rotated 15°. Measurement of significant varus or loss of VL of the femoral neck can be considered accurate regardless of leg rotation at the time of X-rays being taken.  相似文献   
133.
Whether intimate partner violence (IPV) perpetration and victimization are associated with human immunodeficiency virus (HIV) risk behaviors is seldom investigated in Russia. The present study hypothesized that patients from a sexually transmitted infection center in Russia who perpetrated IPV or were victims of IPV would be more likely to have HIV risk behaviors including injection drug use, multiple partners, and inconsistent condom use than those who were not involved with IPV. We used a self-administered questionnaire to collect information from 381 patients on demographics, health status, injection drug use, sexual behaviors, and violence involving sexual partners between 2008 and 2009. After including sociodemographics, lifetime IPV perpetration was significantly associated with having had multiple sexual partners among male patients (odds ratio [OR] = 2.61, p < .05). IPV victimization was significantly associated with injection drug use among male and female patients (OR = 5.22, p < .05) and with inconsistent condom use among female patients (OR = 8.93, p < .05). IPV perpetration and victimization were common among male and female study participants and were associated with greater HIV risk behaviors. HIV prevention programs in Russia should address the risks associated with IPV among people at risk for HIV.  相似文献   
134.

Background/Objective

Preconditioning has been considered promising for the treatment of ischemic flaps. In this study, the therapeutic effect of postconditioning was compared with that of preconditioning during ischemia/reperfusion (I/R) injury, and a role of inducible nitric oxide synthase (iNOS) in postconditioning treatment was also explored.

Methods

Sixty rats were randomly divided into four groups with 15 rats in each group. Ischemic injury was induced in a rat’s gracilis muscle flap model. Preconditioning and postconditioning were performed respectively on the flaps in the pre-con group and the post-con group. No treatment was given to the flaps in the control group, and flaps without I/R injury were used as a sham control. Muscle viability ratio, histology, and gene expression of iNOS were examined at different time intervals (3, 12, and 18 h).

Results

A significantly higher survival ratio was observed in both the pre-con group (78.98 ± 3.39, 62.74 ± 3.7, and 54.42 ± 4.45 %) and the post-con group (77.42 ± 4.14, 59.74 ± 6.67, and 49.52 ± 4.13 %) than the control group (45.22 ± 3.69, 42.44 ± 3.76, and 33.2 ± 3.29 %) at 3, 12, and 18 h postoperatively (P < 0.05). There was no statistical difference between the pre-con group and the post-con group (P > 0.05). Histological examination showed delayed and attenuated tissue damage in both the pre-con group and the post-con group when compared to that of the control group. A higher expression of iNOS was observed in both the pre-con group and the post-con group than the control group and the sham group (P < 0.05).

Conclusions

Significant improvement of flap survival could be achieved by both preconditioning and postconditioning treatments; however, better protection could be provided by preconditioning. The higher expression of iNOS may play an important role in the therapeutic effect of postconditioning during I/R injury.  相似文献   
135.

Background

Fear of disease recurrence is well documented among cancer survivors, but its significance among patients treated for solid pancreatic and periampullary neoplasms is unknown despite the known risk of recurrence associated with these tumors. We hypothesized that fear of cancer recurrence (FCR) represents a common source of psychosocial distress in this population and sought to characterize subgroups for whom FCR might represent a target for intervention to improve quality of life.

Methods

We conducted a cross-sectional study of FCR in patients who were disease-free after potentially curative pancreatectomy for ductal or periampullary adenocarcinoma or pancreatic neuroendocrine tumor. We assessed seven discrete dimensions of FCR using the Fear of Recurrence Inventory and evaluated quality of life and psychosocial distress using the Functional Assessment of Cancer Therapy-Hepatobiliary Questionnaire and the Hospital Anxiety and Depression Scale.

Results

Of 354 eligible patients, 240 (68?%) participated in the study a median of 48?months after potentially curative pancreatectomy. An FCR severity score indicative of frequent fearful thoughts, emotional disturbance and functional impairment was identified in 37, 28, and 35?% of patients with pancreatic adenocarcinoma, nonpancreatic periampullary adenocarcinoma, and pancreatic neuroendocrine tumor, respectively. Anxiety (P?<?0.001) and low quality of life (P?=?0.028) were independently associated with a clinically significant level of FCR, but histopathologic diagnosis and clinicopathologic markers of prognosis were not.

Conclusions

FCR represents a significant concern for one-third of patients after curative surgery for a pancreatic or periampullary tumor, regardless of their actual likelihood of recurrence or disease-related death.  相似文献   
136.
The McGurk effect demonstrates the influence of visual cues on auditory perception. Mismatching information from both sensory modalities can fuse to a novel percept that matches neither the auditory nor the visual stimulus. This illusion is reported in 60-80% of trials. We were interested in the impact of ongoing brain oscillations-indexed by fluctuating local excitability and interareal synchronization-on upcoming perception of identical stimuli. The perception of the McGurk effect is preceded by high beta activity in parietal, frontal, and temporal areas. Beta activity is pronounced in the left superior temporal gyrus (lSTG), which is considered as a site of multimodal integration. This area is functionally (de)coupled to distributed frontal and temporal regions in illusion trials. The disposition to fuse multisensory information is enhanced as the lSTG is more strongly coupled to frontoparietal regions. Illusory perception is accompanied by a decrease in poststimulus theta-band activity in the cuneus, precuneus, and left superior frontal gyrus. Event-related activity in the left middle temporal gyrus is pronounced during illusory perception. Thus, the McGurk effect depends on fluctuating brain states suggesting that functional connectedness of left STS at a prestimulus stage is crucial for an audiovisual percept.  相似文献   
137.
BACKGROUND: In previous studies, pyridoxamine (PM) limited the formation of advanced glycation end products (AGEs) and development of nephropathy in streptozotocin-diabetic rats without affecting glycemic control. However, the lipid-lowering effects of PM and the correlation of plasma cholesterol and triglycerides with AGEs in skin collagen suggested that lipids might be an important source of AGEs in the diabetic rat. This study addresses the effects of hyperlipidemia on formation of advanced glycation and lipoxidation end products (AGE/ALEs) and the effects of PM on hyperlipidemia, hypertension, AGE/ALE formation, and development of nephropathy in the nondiabetic, Zucker obese rat. METHODS: Three groups of Zucker rats were studied: lean (Fa/fa), untreated fatty (fa/fa), and fa/fa treated with PM (2 g/L drinking water). Blood pressure, plasma lipids and creatinine, and urinary albumin were measured monthly. AGE/ALEs were measured in skin collagen by high-performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS). Changes in wall thickness of the aorta and renal arterioles were evaluated by light microscopy. RESULTS: AGE/ALEs formation was increased two- to threefold in skin collagen of obese versus lean rats. PM inhibited the increases in AGE/ALEs in collagen, and significantly decreased the rise in plasma triglycerides, cholesterol, and creatinine, corrected hypertension and thickening of the vascular wall, and nearly normalized urinary protein and albumin excretion in Zucker fa/fa rats. CONCLUSION: Lipids are an important source of chemical modification of tissue proteins, even in the absence of hyperglycemia. PM inhibited AGE/ALE formation and hyperlipidemia and protected against renal and vascular pathology in a nondiabetic model.  相似文献   
138.
139.
A national conference on organ donation after cardiac death (DCD) was convened to expand the practice of DCD in the continuum of quality end-of-life care. This national conference affirmed the ethical propriety of DCD as not violating the dead donor rule. Further, by new developments not previously reported, the conference resolved controversy regarding the period of circulatory cessation that determines death and allows administration of pre-recovery pharmacologic agents, it established conditions of DCD eligibility, it presented current data regarding the successful transplantation of organs from DCD, it proposed a new framework of data reporting regarding ischemic events, it made specific recommendations to agencies and organizations to remove barriers to DCD, it brought guidance regarding organ allocation and the process of informed consent and it set an action plan to address media issues. When a consensual decision is made to withdraw life support by the attending physician and patient or by the attending physician and a family member or surrogate (particularly in an intensive care unit), a routine opportunity for DCD should be available to honor the deceased donor's wishes in every donor service area (DSA) of the United States.  相似文献   
140.

Background

In low- and middle-income countries, the volume of traumatic injuries requiring orthopaedic intervention routinely exceeds the capacity of available surgical resources. The objective of this study was to identify predictors of surgical care for lower extremity fracture patients at a high-demand, resource-limited public hospital in Uganda.

Methods

Skeletally mature patients admitted with the intention of definitive surgical treatment of an isolated tibia or femur fractures to the national referral hospital in Uganda were recruited to participate in this study. Demographic, socioeconomic, and clinical data were collected through participant interviews at the time of injury and 6 months post-injury. Social capital (use of social networks to gain access to surgery), financial leveraging, and ethnicity were also included as variables in this analysis. A probit estimation model was used to identify independent and interactive predictors of surgical treatment.

Results

Of the 64 patients included in the final analysis, the majority of participants were male (83%), with a mean age of 40.6, and were injured in a motor vehicle accident (77%). Due to resource constraints, only 58% of participants received surgical care. The use of social capital and femur fractures were identified as significant predictors of receiving surgical treatment, with social capital emerging as the strongest predictor of access to surgery (p < 0.05).

Conclusion

Limited infrastructure, trained personnel, and surgical supplies rations access to surgical care. In this environment, participants with advantageous social connections were able to self-advocate for surgery where demand for these services greatly exceeded available resources.
  相似文献   
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