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111.
JB Tebbetts 《Canadian Metallurgical Quarterly》1998,102(5):1690-1697
Numerous complications and increased operating times were reported with ultrasonically assisted lipoplasty in the first several months after introduction of the technology in the United States. The purpose of this study was to review early reported complications and management regimens, evaluate possible causes of problems, and apply indications and techniques to attempt to minimize complications during an initial experience with this technique beginning in January of 1997. Seven specific indications and modifications of existing techniques were developed and applied to an initial clinical series of 70 consecutive patients who underwent ultrasound-assisted suction lipoplasty between January 10, 1997, and August 1, 1997. Follow-up ranged from 1 to 7 months. No perioperative or postoperative complication occurred in any patient in this series. In this series of ultrasound-assisted lipoplasty cases, application of the following criteria resulted in a series of 70 patients with 1 to 7-month follow-up without complications: (1) selecting patients with well localized fat deposits who were no more than 20 percent above their ideal body weight; (2) infusing a solution of Ringer's Lactate containing 1 cc of 1:1000 epinephrine per 1000 cc into the area of fat removal, stopping infusion when the tissues first become firm, not infusing to marked tissue turgor or skin induration; (3) restricting the level of energy application to a minimum of 1 cm from the undersurface of the dermis; (4) limiting ultrasonic energy application in each area to approximately 1 minute per estimated 100 cc of total aspirate in a wet to superwet environment; (5) not performing ultrasound-assisted lipoplasty in the same area as another procedure that could potentially compromise tissue vascularity; (6) using a Lysonix 2000 generator and 5-mm golf tee tip probe at a power setting of 8 to apply ultrasonic energy to the area of fat removal, ceasing energy application when tissue resistance to the passage of the probe decreases and moving the cannula as rapidly as tissue resistance allows; and (7) using a standard elastic garment without adherent foam or other materials for 2 weeks postoperatively, encouraging all normal activity immediately, and restricting aerobic activities for 2 weeks. 相似文献
112.
JB Stetson 《Canadian Metallurgical Quarterly》1998,36(4):1-15
Stroke is the third leading cause of death in the United States. Carotid artery stenting is being investigated as a therapeutic strategy for the management of extracranial bifurcation stenosis and has the potential to prevent stroke in thousands of patients. Carotid endarterectomy, although effective, does have limitations, and percutaneous techniques may offer an alternative method of treatment, especially for those who are at highest risk. Although the technique is still evolving, this article describes the protocol and technique of stent-supported carotid angioplasty and care for patients undergoing this procedure at Washington Adventist Hospital in Takoma Park, MD. 相似文献
113.
The changes in the serum level of selenium in cases with pathologic pregnancies are still not clear. The aim of the present study was to determine whether serum selenium in cases with missed abortion differed from selenium concentration in serum during first trimester of normal pregnancy. Twenty-three women with missed abortion and 61 with normal pregnancy were included in the study. We found a statistically significant (p < 0.001) elevation of serum selenium level in cases with missed abortion (928 +/- 335 nmol/l) comparing with those with normal pregnancy (568 +/- 77 nmol/l). We discuss the possible mechanisms of the observed changes. 相似文献
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Over the past few years, there has been an increasing interest in making oligonucleotides specific for ammonia-oxidizing bacteria (AOB), in order to detect and monitor these slow growing bacteria in environmental samples, in enrichment cultures and in wastewater treatment plants. Based on 16S rDNA sequences, a broad selection of oligonucleotides have been designed, either encompassing all known AOB in the beta-subgroup of the Proteobacteria (beta AOB), or subclasses within beta AOB. Thirty different oligonucleotides have so far been published, with varying specificity. The first AOB-specific oligonucleotides published were obtained as a result of an alignment of only eleven 16S rDNA sequences from AOB. Including the present study, there are now forty nearly full length 16S rDNA sequences available from these bacteria, in addition to a number of partial sequences, so that an improved evaluation of the published oligonucleotides can be done. Two new 16S rRNA gene sequences from Nitrosospira are presented here, in a phylogenetic analysis containing every 16S rRNA gene sequences (> 1 kb) available from AOB. On the basis of an alignment of all these sequences, combined with searches in the nucleotide sequence databases, an evaluation of the thirty published oligonucleotides is presented. The analysis expose the strength and weakness of each oligonucleotide and discuss the use of oligonucleotides specific for 16S rRNA genes in future studies of AOB. The present work also identifies one new, broad range primer, specific for the AOB in the beta-subgroup of the Proteobacteria. 相似文献
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Congenital dislocation of the knee is a uncommon malformation. Frequently there is an association with other congenital deformities including congenital dislocation of the hip. The classification of Leveuf and Pais into three separate groups (Type A, Type B, Type C) is now widely accepted. Between October 1989 and April 1995 we evaluated ten children (five girls and five boys) with twelve dislocated knees. Clinical, radiographic and different ultrasonography examinations were carried out on both knees. The sonographic classification showed Type A in 3, Type B in 5 and Type C in 4 cases. The sonographic examination revealed the essential anatomic structures and their pathomorphology. The anterior and the posterior cruciate ligament could be demonstrated in the majority of the cases. Three dislocated knees showed an obliteration of the recessus suprapatellaris and fibrotic changes in the m. quadriceps. These cases required operative treatment. With conservative treatment we achieved a satisfactory result in eight children with nine disease knees. There was a good functional result with an average flexion of 106 degrees. Early conservative treatment recommend as the therapy of choice. Ultrasonography imaging offers the possibility of reliable differentiation into one of the three groups of the classification of Leveuf and Pais. Radiographic documentation during the therapy has become the exception. Ultrasonography imaging helped substantially in the decision making and the timing of operative treatment. 相似文献
119.
For ultrasonographic B-scan images collected by means of a handheld transducer moving in the elevational direction, frame spacings are computed with a speckle-decorrelation algorithm, without additional positioning hardware. Fully developed speckle volumes are automatically segmented and spacing computed from the decorrelation curves. Position accuracy is within 10% for phantoms and 15% for breast studies. The algorithm provides image-based registration, which allows accurate three-dimensional volume rendering. 相似文献
120.
JB Thomas SW Mascarella RB Rothman JS Partilla H Xu KB McCullough CM Dersch BE Cantrell DM Zimmerman FI Carroll 《Canadian Metallurgical Quarterly》1998,41(11):1980-1990
A study of the binding site requirements associated with the N-substituent of (+)-(3R,4R)-dimethyl-4-(3-hydroxyphenyl)piperidine (4) derivatives was undertaken using a set of rigid vs flexible N-substituents. The study showed that compounds 7-9 bearing the trans-cinnamyl N-substituent most closely reproduced the potency at the opioid receptor of the flexible N-propylphenyl or N-propylcyclohexyl analogues previously reported. Neither the N-substituted cis-cinnamyl nor the cis-phenylcyclopropylmethyl compounds 10 and 11, respectively, showed high affinity for the opioid receptor. However, the N-trans-phenylcyclopropylmethyl compound 12 closely approximated the affinity of compounds 7-9. Additionally, we found that free rotation of the phenyl ring is necessary for high affinity binding and mu receptor subtype selectivity as the planar N-substituted thianaphthylmethyl and benzofuranylmethyl compounds 13 and 14 had significantly lower binding affinities. Altogether, these findings suggest that the high binding affinity, selectivity, and antagonist potency of N-propylphenyl or N-propylcyclohexyl analogues of (+)-(3R, 4R)-dimethyl-4-(3-hydroxyphenyl)piperidine (4) are achieved via a conformation wherein the connecting chain of the N-substituents is extended away from piperidine nitrogen with the appended ring system rotated out-of-plane relative to the connecting chain atoms. This conformation is quite similar to that observed in the solid state for 5, as determined by single crystal X-ray analysis. Additionally, it was found that, unlike naltrexone, N-substituents bearing secondary carbons attached directly to the piperidine nitrogen of 4 suffer dramatic losses of potency vs analogues not substituted in this manner. Using a functional assay which measured stimulation or inhibition of [35S]GTP-gamma-S binding, we show that the trans-cinnamyl analogues of (+)-(3R, 4R)-dimethyl-4-(3-hydroxyphenyl)piperidine (4) retain opioid pure antagonist activity and possess picomolar antagonist potency at the mu receptor. 相似文献