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71.
We retrospectively reviewed 187 patients who presented with neurologic abnormality after total joint arthroplasty to establish the incidence of diagnosed organic brain disorders in these patients and determine the utility of advanced head imaging studies. 139 of 187 (74.3%) patients underwent imaging for altered mental status (AMS) and 48 patients for a focal neurologic deficit (FND). Acute findings on head imaging were more common in the FND group. The incidence of stroke and transient ischemic attack was significantly lower in the AMS group compared to FND group (Stroke: 0% vs 12.5%, p < 0.001; TIA: 0% vs. 16.7%, P < .001). Advanced head imaging for evaluation of TJA patients with a change in mental status is of low yield. An algorithm for evaluation of these patients is proposed.  相似文献   
72.

Context:

Cirrhosis of liver is an important cause of morbidity and mortality and if associated with peripheral neuropathy (PN) it also poses a huge financial, psychological burden for the patients and their families.

Aim:

The aim of the present study was to study the magnitude of PN among subjects with cirrhosis of liver presenting to tertiary care teaching hospital in central rural India.

Settings and Design:

A cross-sectional study was performed in a tertiary care teaching hospital.

Materials and Methods:

In all patients of cirrhosis of liver irrespective of etiology, aged 15 and above, undergone clinical assessment for peripheral nervous systems damage and confirmed by nerve conduction studies.

Statistical Analysis Used:

We used chi square test to study associations. P value ≤0.05 was considered as significant. Crude odds ratios were computed to assess the strength of association between independent variables and dependent variables along with their 95% confidence intervals.

Results:

We included 207 of cirrhosis of liver patients admitted in medicine department from November 2010 through November 2013. Nearly 83% patients were male and 63.2% patients were under the age of 45 years. Common features in these patients were ascites (71%) splenomegaly (63.3%) pedal edema (61.4%) icterus (46.4%) tingling (44.9%) gastrointestinal bleeding(39.1%), ataxia (26.6%), numbness(26.6%), distal motor weakness (21.7%) and paresthesia(20.8%). Among the manifestation of peripheral nerve involvement, loss of ankle reflex was the most common feature in 51.7%, followed by loss of temperature sense 29.5%, loss of vibration sense 20.8%, loss of touch 16.4%, loss of position sense 14.5% and loss of pain in 6.3% of the patients. Peripheral neuropathy was found in 53.6% [95% CI: 46.58- 60.56] study subjects on electrophysiological study.

Conclusions:

Analysis of electrophysiological study shows that the PN is very common in study subjects with cirrhosis of liver, especially in male subjects, during the middle age group.  相似文献   
73.

Background

Musculoskeletal disorders of the upper extremity are common reasons for patients to seek care and undergo ambulatory surgery. The objective of our study was to assess the overall and age-adjusted utilization rates of rotator cuff repair, shoulder arthroscopy performed for indications other than rotator cuff repair, carpal tunnel release, and wrist arthroscopy performed for indications other than carpal tunnel release in the United States. We also compared demographics, indications, and operating room time for these procedures.

Methods

We used the 2006 National Survey of Ambulatory Surgery to estimate the number of procedures of interest performed in the United States in 2006. We combined these data with population size estimates from the 2006 U.S. Census Bureau to calculate rates per 10,000 persons.

Results

An estimated 272,148 (95% confidence intervals (CI)?=?218,994, 325,302) rotator cuff repairs, 257,541 (95% CI?=?185,268, 329,814) shoulder arthroscopies excluding those for cuff repairs, 576,924 (95% CI?=?459,239, 694,609) carpal tunnel releases, and 25,250 (95% CI?=?17,304, 33,196) wrist arthroscopies excluding those for carpal tunnel release were performed. Overall, carpal tunnel release had the highest utilization rate (37.3 per 10,000 persons in persons of age 45–64 years; 38.7 per 10,000 persons in 65–74 year olds, and; 44.2 per 10,000 persons in the age-group 75 years and older). Among those undergoing rotator cuff repairs, those in the age-group 65–74 had the highest utilization (28.3 per 10,000 persons). The most common indications for non-cuff repair related shoulder arthroscopy were impingement syndrome, periarthritis, bursitis, and instability/SLAP tears. Non-carpal tunnel release related wrist arthroscopy was most commonly performed for ligament sprains and diagnostic arthroscopies for pain and articular cartilage disorders.

Conclusions

Our data shows substantial age and demographic differences in the utilization of these commonly performed upper extremity ambulatory procedures. While over one million upper extremity procedures of interest were performed, evidence-based clinical indications for these procedures remain poorly defined.  相似文献   
74.
Background contextCauda equina syndrome is caused by compression or injury to the nerve roots distal to the level of the spinal cord. This syndrome presents as low back pain, motor and sensory deficits in the lower extremities, and bladder as well as bowel dysfunction. Although various etiologies of cauda equina syndrome have been reported, a less common cause is infection.PurposeTo report a case of cauda equina syndrome caused by infection of an intradural extramedullary abscess with Staphylococcus aureus.Study design/settingCase report and review of the literature.MethodsThe literature regarding the infectious causes of cauda equina syndrome was reviewed and a case of cauda equina syndrome caused by infection of an intradural extramedullary abscess with Staphylococcus aureus was reported.ResultsA 37-year-old woman, with history of intravenous drug abuse, hepatitis C, and hepatitis B, presented with low back pain lasting 2 months, lower extremity pain, left greater than right with increasing weakness and difficulty ambulating, and urinary and fecal incontinence. Her presentation was consistent with cauda equina syndrome. The patient underwent a T12–L2 laminectomy, and intradural exploration revealed an abscess. Methicillin-resistant Staphylococcus aureus was found on wound culture.ConclusionsCauda equina syndrome, presenting as a result of spinal infection, such as the case reported here, is extremely rare but clinically important. Surgical intervention is generally the recommended therapeutic modality.  相似文献   
75.
Ti-6Al-4V is an alloy that has a high strength-to-weight ratio. It is known as an alpha-beta titanium alloy with excellent corrosion resistance. This alloy has a wide range of applications, e.g., in the aerospace and biomedical industries. Examples of alpha stabilizers are aluminum, oxygen, nitrogen, and carbon, which are added to titanium. Examples of beta stabilizers are titanium–iron, titanium–chromium, and titanium–manganese. Despite the exceptional properties, the processing of this titanium alloy is challenging when using conventional methods as it is quite a hard and tough material. Nonconventional methods are required to create intricate and complex geometries, which are difficult with the traditional methods. The present study focused on machining Ti-6Al-4V using wire electrical discharge machining (WEDM) and conducting numerous experiments to establish the machining parameters. The optimal setting of the machining parameters was predicted using a multiresponse optimization technique. Experiments were planned using the response surface methodology (RSM) technique and analysis of variance (ANOVA) was used to determine the significance and contribution of the input parameters to changes in the output characteristics (cutting speed and surface roughness). The cutting speed obtained during the processing of the annealed titanium alloy using WEDM was quite large as compared to the cutting speed obtained in the case of processing the pure, quenched, and hardened titanium alloys using WEDM. The maximum cutting speed obtained while processing the annealed titanium alloy was 1.75 mm/min.  相似文献   
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79.
Conjugated copolymers have attracted much attention because of their outstanding photo-physical properties. The present work reports for the first time, microwave-assisted copolymerization of o-phenylenediamine with luminol using different weight ratios of the two monomers. The composition of the copolymers was confirmed by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (1H-NMR) while monomer reactivity ratios were determined using the Fineman–Ross method. Ultraviolet-visible spectroscopy revealed the variation in polaronic states upon copolymerization while X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses showed the morphology of the copolymers to be intermediate between that of the homopolymers. Confocal analysis and fluorescence studies revealed that the copolymers showed composition based blue as well as red emission which could be utilized for in vivo imaging of cancer cells.

Development of bioimaging agents based on poly(o-phenylendiamine and luminol).  相似文献   
80.
PurposeObesity has attained pandemic proportions across the world, and its prevalence in developing countries is also on the rise. Nevertheless, there is still a large gap in understanding the reasons behind a disproportionately high prevalence of diabetes as opposed to a lesser degree of obesity seen in individuals of South Asian origin. This research letter highlights the importance of identifying individuals with normal weight obesity, which may partially bridge this knowledge gap.MethodsWe reviewed recently published evidence on normal weight obesity.FindingsNormal weight obesity is a common public health problem and may be prevalent in up to one-third of individuals of certain Asian ethnicities. Literature is emerging on its pathophysiology and association with metabolic diseases, such as type 2 diabetes mellitus, hypertension, and dyslipidemia. More recently, normal weight obesity was also identified as an independent strong predictor of cardiovascular mortality. However, evidence is particularly lacking on its appropriate management.ImplicationsNormal weight obesity is an underrecognized yet widely prevalent problem in individuals of Asian descent. Further research on pathogenic mechanisms, diagnostic modalities, and therapeutic options in individuals with normal weight obesity is needed to appropriately manage this condition.  相似文献   
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