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51.
Foreign bodies in soft tissues are commonly encountered in daily orthopaedic practice. While most of the metals and glass foreign bodies can be detected by plain radiograph, organic substances such as wood and vegetative materials are radiolucent. Unfortunately, these radiolucent foreign bodies are usually more prone to cause an inflammatory reaction and infection. The detection can be even more difficult in cases of multiple foreign bodies and in penetrating injuries with small innocuous skin wounds. Ultrasonography is a sensitive and reliable investigation for detection of foreign bodies in soft tissue. We present a case of penetration injury to thumb with residual radiolucent foreign bodies and demonstrate the proper role of ultrasonography in the management of foreign bodies in soft tissues.  相似文献   
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53.
Thirteen patients with refractory, recurrent, life-threatening ventricular tachycardia (VT) underwent electrophysiologic testing before and after long-term amiodarone therapy. Nine patients (69%) had coronary artery disease, 3 (23%) had nonischemic cardiomyopathy and 1 patient (8%) had mitral valve prolapse. At control electrophysiologic study, programmed electrical stimulation (PES) induced VT in all patients: sustained VT in 11 and nonsustained VT in 2 (9 beats and 31 beats). After oral loading with amiodarone, 1200 mg/day for 14 days, followed by maintenance therapy with 408 +/- 20 mg/day (mean +/- standard error of the mean), repeat PES at 6 +/- 1.6 months revealed inducible VT in 12 of 13 patients: sustained VT in 11 and nonsustained VT (32 beats) in 1 patient. Inducible VT was suppressed in only 1 patient. Amiodarone significantly increased sinus cycle length, PR interval, QRS duration and right ventricular effective refractory period. Insignificant increases in AH, HV and QTc intervals were noted. At 24 +/- 2 months, 8 patients (62%) (all with inducible VT at late PES) were free of clinical arrhythmic events (syncope or sudden death), compared with 5 patients (38%) (4 with inducible VT at late PES) with events. There were no significant differences in the induced VT cycle length, VT cycle length change, ease of inducibility or hemodynamic response to induced VT at late PES in patients with and without arrhythmic events.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
54.
The electron optical analog of immunofluorescence microscopy combines three developments: (i) photo-electron microscopy to produce a high-resolution image of exposed components of the cell, (ii) site-specific antibodies, and (iii) photoemissive markers coupled to the antibodies to make the distribution of sites visible. This approach, in theory, provides a way to extend the useful immunofluorescence microscopy technique to problems requiring much higher resolution. The resolution limit of fluorescence microscopy is limited to about 200 nm by the wavelength of the light used to form the image, whereas in photoelectron microscopy the image is formed by electrons (current resolution: 10-20 nm; theoretical limit: 5 nm or better depending on the electron optics). As a test system, cytoskeletons of CV-1 epithelial cells were prepared under conditions that preserve microtubules, and the microtubule networks were visualized by both indirect immunofluorescence and immunophotoelectron microscopy using colloidal gold coated with antibodies. Colloidal gold serves as a label for immunophotoelectron microscopy, providing enhanced photoemission from labeled cellular components so that they stand out against the darker background of the remaining unlabeled structures. In samples prepared for both immunofluorescence and immunophotoelectron microscopy, individual microtubules in the same cells were visualized by both techniques. The photoemission of the colloidal gold markers is sufficiently high that the microtubules are easily recognized without reference to the immunofluorescence micrographs, indicating that this approach can be used, in combination with antibodies, to correlate structure and function in cell biological studies.  相似文献   
55.
Twenty-two patients with coronary artery disease and spontaneous ventricular tachycardia (VT) or ventricular fibrillation (VF) underwent intracardiac electrophysiologic evaluation and, when possible, ambulatory monitoring before and after therapy with flecainide (mean dose 418 +/- 87 mg [mean +/- standard deviation]). An average of 4 antiarrhythmic agents were used and were unsuccessful before therapy with flecainide was begun. During 64 +/- 16 hours of control Holter monitoring in 16 patients, all had 1 or more salvos of VT, as well as ventricular premature complexes (VPCs). Programmed stimulation during the control period induced VT in 17 of 22 patients. After flecainide therapy, Holter monitoring showed elimination of all forms of VT in all but 1 patient, as well as significant reduction of paired VPCs by 95% (p less than 0.03) and single VPCs by 70% (p less than 0.005). Electrophysiologic study during flecainide therapy showed significant increases in AH, HV, PR, QRS and QTc intervals, and the ventricular effective refractory period. Programmed stimulation in 17 patients taking flecainide, with a mean plasma level of 1,075 +/- 521 ng/ml, showed ablation of inducible VT in only 2 patients, a worsening in 5 and continued VT inducibility in 10. Adverse effects that required drug withdrawal were infrequent and encountered in patients who received higher drug levels: 1 patient with congestive heart failure and 1 with severe sinus bradycardia. Thus, although flecainide suppresses complex ventricular arrhythmias on Holter recordings, it rarely alters the response to programmed stimulation. Caution is recommended in its use for recurrent sustained VT or VF and in the interpretation of electrophysiologic studies until the predictive value of programmed stimulation with flecainide therapy is established.  相似文献   
56.
Aim The 30‐day outcome after laparoscopic resection for cancer in patients over the age of 80 years was studied. Method An electronic database was used to identify patients over 80 years who underwent laparoscopic bowel resection between December 2000 and October 2009 at three UK laparoscopic colorectal training units. Patients who required abdominoperineal excision of the rectum were excluded. Results In all, 173 patients (80 men) of median age 84 (80–93) years were identified. American Society of Anesthesiologists (ASA) grades were ASA 1, 14; ASA 2, 87; ASA 3, 68; and ASA 4, 4. Median body mass index was 26 (14–45) kg/m2. Thirteen (7.5%) patients were converted to open surgery. The major causes for conversion were bleeding and adhesions. Thirty‐three major complications occurred in 21 (12%) patients. Ten (5.8%) required readmission after discharge for complications giving a total of 17.8% of patients with complications. The median hospital stay was 5 (1–37) days. Three (1.7%) patients died within 30 days of surgery. Conclusion This study confirms that laparoscopic large bowel resection is safe and beneficial in a population over 80 years. It has low morbidity and mortality and a shortened hospital stay. Octogenarians should not be denied major laparoscopic bowel surgery based on age alone.  相似文献   
57.
We assessed the relationship of bone density and microarchitecture between hand, peripheral, and axial skeletal sites using high-resolution peripheral quantitative computed tomography (HR-pQCT) and dual-energy X-ray absorptiometry (DXA) in patients with rheumatoid arthritis (RA) and which factors influence these parameters. This was a cross-sectional study of 100 female patients (53.4?±?9.3?years) with RA. HR-pQCT scans at distal radius and the second metacarpal head were performed to assess cortical and trabecular volumetric bone mineral density (vBMD) and microarchitecture. DXA scans at the hip, lumbar spine, and ultradistal radius were performed to assess areal BMD. There was significant correlation in vBMD and microarchitectural parameters between the second metacarpal head and distal radius (r?=?0.201?0.628). Areal BMD at the axial skeleton was moderately associated with vBMD at the peripheral sites (r?=?0.354–0.558). Factors related to disease severity/chronicity significantly correlated with vBMD and microarchitecture at the distal radius and the second metacarpal head. Factors related to disease activity were more likely to correlate with vBMD and microarchitecture at the second metacarpal head but not those at the distal radius. HR-pQCT is a promising technique that is capable of providing detailed quantitative assessment of disease-associated periarticular bone loss at both cortical and trabecular bone compartments in patients with RA. Future longitudinal studies will be needed to investigate whether assessment by HR-pQCT can be used as a marker of disease activity and a predictor of disease progression in RA.  相似文献   
58.
OBJECTIVE: We sought to determine the tumor control rate and cranial nerve function outcomes in patients with vestibular schwannomas who were treated with proton beam stereotactic radiosurgery. METHODS: Between November 1992 and August 2000, 88 patients with vestibular schwannomas were treated at the Harvard Cyclotron Laboratory with proton beam stereotactic radiosurgery in which two to four convergent fixed beams of 160-MeV protons were applied. The median transverse diameter was 16 mm (range, 2.5-35 mm), and the median tumor volume was 1.4 cm(3) (range, 0.1-15.9 cm(3)). Surgical resection had been performed previously in 15 patients (17%). Facial nerve function (House-Brackmann Grade 1) and trigeminal nerve function were normal in 79 patients (89.8%). Eight patients (9%) had good or excellent hearing (Gardner-Robertson [GR] Grade 1), and 13 patients (15%) had serviceable hearing (GR Grade 2). A median dose of 12 cobalt Gray equivalents (range, 10-18 cobalt Gray equivalents) was prescribed to the 70 to 108% isodose lines (median, 70%). The median follow-up period was 38.7 months (range, 12-102.6 mo). RESULTS: The actuarial 2- and 5-year tumor control rates were 95.3% (95% confidence interval [CI], 90.9-99.9%) and 93.6% (95% CI, 88.3-99.3%). Salvage radiosurgery was performed in one patient 32.5 months after treatment, and a craniotomy was required 19.1 months after treatment in another patient with hemorrhage in the vicinity of a stable tumor. Three patients (3.4%) underwent shunting for hydrocephalus, and a subsequent partial resection was performed in one of these patients. The actuarial 5-year cumulative radiological reduction rate was 94.7% (95% CI, 81.2-98.3%). Of the 21 patients (24%) with functional hearing (GR Grade 1 or 2), 7 (33.3%) retained serviceable hearing ability (GR Grade 2). Actuarial 5-year normal facial and trigeminal nerve function preservation rates were 91.1% (95% CI, 85-97.6%) and 89.4% (95% CI, 82-96.7%). Univariate analysis revealed that prescribed dose (P = 0.005), maximum dose (P = 0.006), and the inhomogeneity coefficient (P = 0.03) were associated with a significant risk of long-term facial neuropathy. No other cranial nerve deficits or cancer relapses were observed. CONCLUSION: Proton beam stereotactic radiosurgery has been shown to be an effective means of tumor control. A high radiological response rate was observed. Excellent facial and trigeminal nerve function preservation rates were achieved. A reduced prescribed dose is associated with a significant decrease in facial neuropathy.  相似文献   
59.
Tissue engineering seeks to translate scientific knowledge into tangible products to advance the repair, replacement, or regeneration of organs and tissues. Current tissue engineering strategies have progressed recently from a historical approach that is based primarily on biomaterials to a cell and tissue-based approach that includes understanding of cell-sourcing and bioactive stimuli. New options include methods for harvest and transplantation of tissue-forming cells, bioactive matrix materials that act as tissue scaffolds, and delivery of bioactive molecules within scaffolds. These strategies are already benefiting patients, and they place increasing demands on orthopaedic surgeons to have a solid foundation in the contemporary concepts and principles of cell-based tissue engineering. Essentially all orthopaedic tissue engineering strategies can be distilled to a strategy or combination of strategies that seek to increase the number or relative performance of bone-forming cells. The global term connective tissue progenitors has been used to define the heterogeneous populations of stem and progenitor cells that are found in native tissue and that are capable of differentiating into one or more connective tissue phenotypes. These stem or progenitor populations are found in various tissue sources, with varying degrees of ability to differentiate along connective tissue lineages. Available cell-based strategies include targeting local cells with use of scaffolds or bioactive factors, or transplantation of autogenous connective tissue progenitor cells derived from bone marrow or other tissues, with or without processing to change their concentration or prevalence. The future may include means of homing circulating connective tissue progenitor cells with use of intrinsic chemokine systems, or modifying the biological performance of connective tissue progenitor cells by means of genetic modifications.  相似文献   
60.
Treatment of malaria in the United States: a systematic review   总被引:3,自引:0,他引:3  
Griffith KS  Lewis LS  Mali S  Parise ME 《JAMA》2007,297(20):2264-2277
Context  Many US clinicians and laboratory personnel are unfamiliar with the diagnosis and treatment of malaria. Objectives  To examine the evidence base for management of uncomplicated and severe malaria and to provide clinicians with practical recommendations for the diagnosis and treatment of malaria in the United States. Evidence Acquisition  Systematic MEDLINE search from 1966 to 2006 using the search term malaria (with the subheadings congenital, diagnosis, drug therapy, epidemiology, and therapy). Additional references were obtained from searching the bibliographies of pertinent articles and by reviewing articles suggested by experts in the treatment of malaria in North America. Evidence Synthesis  Important measures to reduce morbidity and mortality from malaria in the United States include the following: obtaining a travel history, considering malaria in the differential diagnosis of fever based on the travel history, and prompt and accurate diagnosis and treatment. Chloroquine remains the treatment of choice for Plasmodium falciparum acquired in areas without chloroquine-resistant strains. In areas with chloroquine resistance, a combination of atovaquone and proguanil or quinine plus tetracycline or doxycycline or clindamycin are the best treatment options. Chloroquine remains the treatment of choice for all other malaria species, with the exception of P vivax acquired in Indonesia or Papua New Guinea, in which case atovaquone-proguanil is best, with mefloquine or quinine plus tetracycline or doxycycline as alternatives. Quinidine is currently the recommended treatment for severe malaria in the United States because the artemisinins are not yet available. Severe malaria occurs when a patient with asexual malaria parasitemia, and no other confirmed cause of symptoms, has 1 or more designated clinical or laboratory findings. The only adjunctive measure recommended in severe malaria is exchange transfusion. Conclusions  Malaria remains a diagnostic and treatment challenge for US clinicians as increasing numbers of persons travel to and emigrate from malarious areas. A strong evidence base exists to help clinicians rapidly initiate appropriate therapy and minimize the major mortality and morbidity burdens caused by this disease.   相似文献   
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