SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
In a surgeon's tool chest there are a variety of incision-making tools, some of frequent, common use in general or specialized surgery such as scalpels or scissors. There also exists an abundant quantity of instruments considered to pertain exclusively to determined surgical specialties.
The historical development of thoracic surgery, which was established in Germany in the years 1904/1905 and the armamentarium of the chest designed by Ferdinand Sauerbruch (1875-1951) are described. Sauerbruch designed between 1904 and 1920 many instruments to facilitate thoracic surgery, e.g. several rib retractors, a special rib shear for the first rib, a rib shear for all ribs other than the first. Furthermore he designed a special lung grasping forceps with rubber covered jaws, a lung compression forceps and a fenestrated lung retractor to facilitate lung resections.
The amputation of a limb is one of the oldest surgical procedures. However, in the course of medical history operative techniques and surgical instruments have been improved continuously. With an example of an amputation case of the last century we will summarize this development until the middle of the nineteenth century. Even in the first century Celsus gave a description of an amputation (circular cut). A major step in the development of the operative technique was the introduction of artery forceps by A. Paré in the sixteenth century. Nevertheless, due to a lack of analgesics and narcotics the operation had to take only a few minutes. Therefore the amputation was completed in one cut, i.e. detachment of the skin, muscles and bone at the same level. This technique known as "classic circular cut" was modified several times in the following period: in order to reduce suture tension Petit recommended to transect the skin first and the muscles and bone more proximal ("two-stage circular cut", 1718) and Bromfield approved to cut in turn the skin first, the muscles more proximal and the bone most proximal ("three-stage circular cut", 1773). Finally, Lowdham (1679), Verduyn (1696) and C. J. M. Langenbeck (1810) changed the operative technique to the effect that they used a soft-tissue flap in order to cover the bone without tension ("flap amputation").
The use of endoscopic video-assisted technique in facial rejuvenation is one of the most recent advances in aesthetic plastic surgery of the face. It replaces the bicoronal incision without the necessity of skin resection. The idea is to detach the muscles from the periorbital attachment, forcing the occipital muscle to pull the forehead tissue back and thus elevating the eyebrows. Therefore, we developed a flexible fiber endoscope that allows the surgeon to guide flexible instruments through its working channel. The endoscope is introduced through a 1-cm midscalp incision so that it can be used to expose and treat soft tissue regions in the forehead, the midface, and the neck.
Described is the Liulin-5 experiment and instrumentation, developed for investigation of the space radiation doses depth distribution in a human phantom on the Russian Segment of the International Space Station (ISS). Liulin-5 experiment is a part of the international project MATROSHKA-R on ISS. The experiment MATROSHKA-R is aimed to study the depth dose distribution at the sites of critical organs of the human body, using models of human body-anthropomorphic and spherical tissue-equivalent phantoms. The aim of Liulin-5 experiment is long term (4-5 years) investigation of the radiation environment dynamics inside the spherical tissue-equivalent phantom, mounted in different places of the Russian Segment of ISS. Energy deposition spectra, linear energy transfer spectra, flux and dose rates for protons and the biologically-relevant heavy ion components of the galactic cosmic radiation will be measured simultaneously with near real time resolution at different depths of the phantom by a telescope of silicon detectors. Data obtained together with data from other active and passive dosimeters will be used to estimate the radiation risk to the crewmembers, verify the models of radiation environment in low Earth orbit, validate body transport model and correlate organ level dose to skin dose. Presented are the test results of the prototype unit. The spherical phantom will be flown on the ISS in 2004 year and Liulin-5 experiment is planned for 2005 year.
Simultaneous monitoring of the vapors in several sewer headspaces by three direct-reading instruments, the Century OVA flame ionization detector, a 10.2 eV H-Nu Photoionization Detector, and a Hydrogen Sulfide Ecolyzer revealed that the majority of condensable organic vapors in areas of the Metropolitan Sewer District of Cincinnati appeared to be saturated aliphatic organics, except during short, unpredictable episodes. The monitoring was performed in the wet well of a sewage treatment plant, in sewers near two chemical plants, and in three other different sewers. The approach outlined in this paper does not require the use of gas chromatography-mass spectrometry (GC-MS) analysis.
OBJECTIVES: To assess the reliability (internal and interrater) and validity (concurrent) of a new interview measure for assessing patients' ability to cope with cancer, the Centre for Clinical Excellence in Urological Research Coping with Cancer Instrument (CCCI), and to determine whether there is an underlying structure to the various coping strategies used by patients with prostate cancer. METHODS: Eighty patients with prostate cancer were interviewed using the CCCI. The participants also completed measures of quality of life and anxiety and depression. RESULTS: The psychometric properties of the CCCI were acceptable. Factor analysis revealed that coping with prostate cancer can be described along five dimensions: positive problem solving (fighting against the illness, seeking information); self-reliance (developing a lay explanation, distrusting doctors); emotional availability (not withdrawing from others); distress (brooding, self-pity); and solace (taking alcohol or drugs to improve mood). These coping styles were correlated with age, quality of life, self-reported prostate-specific antigen level, and measures of anxiety and depression. CONCLUSIONS: The results of the present study have led to a greater understanding of the underlying coping styles used by patients with prostate cancer. Although some of these are similar to those found in other cancer populations, others, such as self-reliance and solace, represent unique and potentially clinically significant responses to prostate cancer diagnosis and treatment. A larger scale longitudinal study is needed to determine the wider clinical implications associated with each coping style.
The Analytical Methods Committee has received and approved the following report from the Instrument Criteria Sub-Committee.
The quality of the reductions achieved in a consecutive series of 55 patients with unstable thoracolumbar fractures were correlated with the method of instrumentation, the type and level of injury, the effects of laminectomy and end-plate fractures, and the length of time from injury to surgery. It was found that many of these variables were associated with significant differences (less than 0.05) in the percent correction achieved in anterior compression, angle of deformity, and sagittal plane translation. Specifically: compression combined with distraction produced the best overall anatomic results, but bilateral compression and bilateral distraction were most effective for reducing flexion--distraction and flexion--axial compression (burst) fractures, respectively; two or more level laminectomies adversely affected reductions; end-plate fractures did not; the best reductions were obtained in flexion--distraction injuries; and the poorest reductions occurred in flexion--axial compression injuries, lumbar fractures, and fractures operated on 6 weeks or more after injury.
BACKGROUND AND PURPOSE: Many patients with ischemic stroke eligible for recombinant tissue plasminogen activator (rt-PA) are not treated in part because of the risks and benefits perceived by treating physicians. Therefore, we aimed to develop a Stroke-Thrombolytic Predictive Instrument (TPI) to aid physicians considering thrombolysis for stroke. METHODS: Using data from 5 major randomized clinical trials (n=2184) testing rt-PA in the 0- to 6-hour window, we developed logistic regression equations using clinical variables as potential predictors of a good outcome (modified Rankin Scale score < or =1) and of a catastrophic outcome (modified Rankin Scale score > or =5), with and without rt-PA. The models were internally validated using bootstrap re-sampling. RESULTS: To predict good outcome, in addition to rt-PA treatment, 7 variables significantly affected prognosis and/or the treatment-effect of rt-PA: age, diabetes, stroke severity, sex, previous stroke, systolic blood pressure, and time from symptom onset. To predict catastrophic outcome, only age, stroke severity, and serum glucose were significant; rt-PA treatment was not. For patients treated within 3 hours, the median predicted probability of a good outcome with rt-PA was 42.9% (interquartile range [IQR]=18.6% to 64.7%) versus 25.3% (IQR=9.8% to 46.2%) without rt-PA; the median predicted absolute benefit was 12.5% (IQR=5.1% to 21.0%). The median probability for a catastrophic outcome, with or without, rt-PA was 15.2% (IQR=8.0% to 31.2%). The area under the receiver-operator characteristic curve was 0.788 for the model predicting good outcome and 0.775 for the model predicting bad outcome. CONCLUSIONS: The Stroke-TPI predicts good and bad functional outcomes with and without thrombolysis. Incorporated into a usable tool, it may assist in decision-making.
BACKGROUND AND PURPOSE: In 1991 we developed the Stroke Prognosis Instrument (SPI-I) to stratify patients with transient ischemic attack or ischemic stroke by prognosis for stroke or death in 2 years. In this article we validate and improve SPI-I (creating SPI-II). METHODS: To validate SPI-I, we applied it to 4 test cohorts and calculated pooled outcome rates. To create SPI-II, we incorporated new predictive variables identified in 1 of the test cohorts and validated it in the other 3 cohorts. RESULTS: For SPI-I, pooled rates (all 4 test cohorts) of stroke or death within 2 years in risk groups I, II, and III were 9%, 17%, and 24%, respectively (P<0.01, log-rank test). SPI-II was created by adding congestive heart failure and prior stroke to SPI-I. Each patient's risk group was determined by the total score for 7 factors: congestive heart failure (3 points); diabetes (3 points); prior stroke (3 points); age >70 years (2 points); stroke for the index event (not transient ischemic attack) (2 points); hypertension (1 point); and coronary artery disease (1 point). Risk groups I, II, and III comprised patients with 0 to 3, 4 to 7, and 8 to 15 points, respectively. For SPI-I, pooled rates (3 cohorts excluding the SPI-II development cohort) of stroke or death within 2 years in risk groups I, II, and III were 9%, 17%, and 23%, respectively. For SPI-II, pooled rates were 10%, 19%, and 31%, respectively. In receiver operator characteristic analysis, the area under the curve was 0.59 (95% CI, 0.57 to 0.60) for SPI-I and 0.63 (95% CI, 0.62 to 0.65) for SPI-II, confirming the better performance of the latter. CONCLUSIONS: Compared with SPI-I, SPI-II achieves greater discrimination in outcome rates among risk groups. SPI-II is ready for use in research design and may have a role in patient counseling.
During the 2002 environmental satellite Envisat mid-latitude validation campaign, a new upgraded configuration of the Infrared Balloon Experiment (IBEX) Fourier transform spectrometer, which had its first flight in 1978, performed a stratospheric balloon flight across the Mediterranean Sea. Among the substantial upgrades made to the instrument, the use of photon-noise-limited detectors permitted us to reach the theoretical limits in terms of signal-to-noise ratio. Also, important modifications were made to the interferometric system and electronics, such as the installation of a solid-state laser reference source and an onboard data recording system. During the flight, measurement of volume-mixing-ratio vertical profiles of O3, HNO3, N2O, and ClO from an altitude of approximately 38 km were performed with a vertical resolution of approximately 1.5 km.
We compared the major characteristics of internationally applied cost assessment instruments (CAI) in rheumatic conditions. Fifteen utilization questionnaires were identified and assessed using a structured approach. The forms differed considerably with respect to applied characteristics: length (3-113 items), recall period (between 1 week and 1 year), format (2 interview, 13 self-administered), response categories, cost units (physical vs monetary), and cost domains covered. While all included a gross assessment of outpatient and inpatient costs, the level of disaggregation differed. Only a few CAI included an assessment of other direct disease related costs (e.g., home remodeling or home health care services) and out-of-pocket expenditure. Productivity costs were included in all but 2 CAI. Efforts to further standardize the applied CAI should (1) be based on sound psychometric data, (2) define a required core set of cost domains covered, (3) discriminate between generic and relevant disease related cost components, and (4) examine the feasibility of developing international standards for cost data.
As on-line instrumentation becomes increasingly important for operating modern wastewater treatment plants it is necessary to have diagnostic methods that can indicate sensor deviation at an early stage. Examples of on-line diagnosis methods used at the Rya WWTP (Göteborg, Sweden) are presented. These include on-line mass balance calculations and soft sensors, which make indirect parameter estimates. By comparing the estimates with the corresponding on-line sensors it is possible to make control decisions and to chose alternative strategies. These comparative methods are often useful for process monitoring and diagnosis as well. Some other soft sensor applications using exponential filters are also presented.
Numerous core composites are used to reconstruct abutments for fixed partial dentures. The preparation is carried out with various type of burs. The purpose of this study is to facilitate the choice among them. Six chemical composites, one glass ionomer cement and two light cured composites have been selected. Calibrated samples have been made, divided into four series and prepared with six different burs used for fixed partial dentures, three of them as finishing burs. In the first part of the investigation, the samples were examined with a S.E.M., in order to visualize the surface texture. According to the materials used, variations may exist. In the second part of the investigation, a tridimensional study was performed using a mechanical scanner microscope which permitted the quantification of some roughness characteristics, thus, an objective comparison of the surfaces became possible. Due to the complementary nature of the two investigation techniques, a protocol is presented for the study of burs instrumentation and prepared tooth surface.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.