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Defects around the elbow region are often irregular with exposed nerves, tendons, bones/joint, and implants. Skin grafts, though possible in some cases, must be avoided, as it requires prolonged splintage and physiotherapy to prevent recurrence and elbow stiffness. Distant flaps require multiple stages, and free flaps are rarely indicated for elbow defects. Muscle flaps are bulky. To overcome these problems, distally based fasciocutaneous flaps from medial and lateral sides of the arm based on posterior ulnar recurrent artery and radial recurrent artery, respectively, were used. Ten patients were studied. Age of the patients ranged from 10 to 40 years. Five were male, and five were female. Radial and ulnar recurrent flaps were used in five patients each. The largest flap size was 18 × 8 cm, and the smallest was 10 × 6 cm. The flaps were islanded in four cases, and in six cases, they were used as pedicled flaps. Skin grafts were used in 90% of the patients because large flaps were required for resurfacing; also, our patients had thinner arms with less girth. All flaps survived well. One island flap had venous congestion and marginal necrosis, which eventually healed. A significant improvement of mobility and elbow movement was noted in all patients. These flaps can be raised even from the previously burnt skin, as the pedicle is located deep. These flaps have the following advantages: The flap is reliable (deeply located consistent vascular pedicle), can cover both the flexor and extensor surface of the elbow joint, avoids prolonged splintage, elbow stiffness, and recurrence, good aesthetic, and has functional results.  相似文献   
64.
Effectiveness and residual activity tests of granular formulations of 2 insect growth regulators (IGRs), s-methoprene and pyriproxyfen, against laboratory-reared larvae of 5 colonized mosquitoes, Aedes aegypti, Aedes albopictus, Aedes taeniorhynchus, Anopheles quadrimaculatus, and Culex nigripalpus, were conducted in the laboratory and outdoors in plastic tubs. Culex quinquefasciatus was exposed to these two IGRs in the laboratory only. Each IGR formulation was applied at 0.02 and 0.05 ppm active ingredient (Al) against 5 of the 6 mosquito species both in the laboratory and the outdoor evaluations, whereas Cx. quinquefasciatus was exposed to 0.2 and 0.4 ppm AI of s-methoprene, and 0.1 and 0.2 ppm AI of pyriproxyfen in the laboratory. s-Methoprene at 0.02 and 0.05 ppm AI resulted in variable levels (<39-100%) of inhibition of adult emergence in the 5 species monitored for 6 weeks after treatment under both test conditions. Aedes taeniorhynchus was the most susceptible to s-methoprene in terms of initial and residual activity. Culex quinquefasciatus and Ae. albopictus were the most tolerant to s-methopene, with maximum emergence inhibitions amounting to 84% in Cx. quinquefasciatus at 0.4 ppm and 44.3% in Ae. albopictus at 0.05 ppm during the 1st week in the laboratory. Pyriproxyfen at comparable treatment rates to s-methoprene caused very high levels (>80-100% in most cases) of initial and residual emergence inhibitions of the tested species in the laboratory as well as outdoors. In several species, pyriproxyfen induced complete inhibition of adult emergence for several weeks after treatment, even at the lower rate of 0.02 ppm. The World Health Organization has recently recommended the use of pyriproxyfen for the control of some mosquito species at specified rates in certain habitats.  相似文献   
65.
Cardiac metastases from renal cell carcinoma are a well-recognized entity. However, this phenomenon is extremely rare in the absence of vena caval extension. The authors report a patient who after successful resection of renal cell carcinoma presented with left ventricular mass causing left ventricular outflow tract obstruction. There was also metastatic pericardial and intramyocardial involvement. Such a unique combination of cardiac metastasis, in the same patient, has not been reported previously.  相似文献   
66.
AIMS AND OBJECTIVES: To identify the role of dental surgical procedures in contributing to the transmission of hepatitis C. DESIGN: Prospective observational pilot study. SETTING: Shaikh Zayed Federal Postgraduate Medical Institute Lahore, Pakistan. METHODS: Exposure to dental procedures, injections, tattooing, surgical intervention, blood transfusions, family history of hepatitis, diabetes mellitus and contact with jaundiced patients was evaluated in 78 consecutive adult patients of both sexes suffering from chronic hepatitis C. MAIN OUTCOME MEASURES: Distribution of risk factors for acquiring hepatitis C with emphasis on role of dentistry as a possible route of transmission. RESULTS: Dental procedures were the major source of exposure (39.7%) followed by injections (16.6%), surgical procedures (16.6%), diabetes (12.8%), family history of hepatitis (9%), blood transfusions (7%), tattooing (5.1%) and history of contact with a jaundiced patient (2.6%). There was a statistically significant difference in distribution of risk factors, with dental procedures being the commonest factor (p < 0.001). CONCLUSIONS: The high prevalence of dental procedures in patients with chronic hepatitis C stresses the importance of ineffective infection control methods practiced by dental surgeons as a risk factor for acquiring hepatitis C and which were probably the source of infection. Large epidemiological studies are needed to elucidate the role of dentistry in transmitting hepatitis C.  相似文献   
67.
Voxelation allows high-throughput acquisition of multiple volumetric images of brain gene expression, similar to those obtained from biomedical imaging systems. To obtain these images, the method employs analysis of spatially registered voxels (cubes). For creation of high-resolution maps using voxelation, relatively small voxel sizes are necessary and instruments will be required for semiautomated harvesting of such voxels. Here, we describe two devices that allow spatially registered harvesting of voxels from the human and rodent brain, giving linear resolutions of 3.3 and 1 mm, respectively. Gene expression patterns obtained using these devices showed good agreement with known expression patterns. The voxelation instruments and their future iterations represent a valuable approach to the genome scale acquisition of gene expression patterns in the human and rodent brain.  相似文献   
68.
BACKGROUND: Adenosine induced bronchoconstriction in patients with asthma is thought to be mediated by the synthesis and release of autacoids from airway mast cells. In vitro, adenosine induced constriction of asthmatic bronchi is blocked by a combination of specific histamine and cysteinyl leukotriene receptor antagonists, but the relative contribution of these mediators in vivo is unclear. We hypothesised that adenosine induced bronchoconstriction in asthmatic patients may be blocked by pretreatment with the orally active selective cysteinyl leukotriene-1 (CysLT(1)) receptor antagonist, montelukast. METHODS: In a randomised, double blind, crossover study, oral montelukast (10 mg) or placebo was administered once daily on two consecutive days to 18 patients with mild to moderate persistent atopic asthma. Incremental doses of adenosine 5'-monophosphate (AMP) from 0.39 to 400 mg/ml were inhaled by dosimeter and the dose producing a 20% fall in FEV(1) (PC(20)AMP) after AMP inhalation was recorded. Leukotriene E(4) (LTE(4)) urinary concentrations were measured by enzyme immunoassay 4 hours after AMP challenge. RESULTS: Montelukast pretreatment provided highly significant protection against adenosine induced bronchoconstriction, with geometric mean PC(20)AMP values of 52.6 mg/ml (95% CI 35.2 to 78.7) after placebo and 123.9 mg/ml (95% CI 83.0 to 185.0) after montelukast (p=0.006). The geometric mean of the montelukast/placebo PC(20)AMP ratio was 2.4 (95% CI 1.3 to 4.2). Montelukast had no significant effect on 4 hour urinary excretion of LTE(4) compared with placebo. CONCLUSIONS: Selective CysLT(1) receptor antagonism with montelukast provides highly significant protection against AMP induced bronchoconstriction in patients with atopic asthma, implying that cysteinyl leukotrienes are generated from airway mast cells through preferential activation of their A(2B) receptors.  相似文献   
69.
Occurrence of life threatening arrhythmias and sudden death during or following sexual activity is infrequent. We describe a patient with an implantable cardioverter defibrillator who developed increased ventricular ectopic activity followed by sustained ventricular tachycardia during extramarital coitus. A review of literature and management is discussed.  相似文献   
70.
The proto-oncogene c-myc in hematopoietic development and leukemogenesis   总被引:29,自引:0,他引:29  
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