Search PubMed⌕ Search

Biomedical subjects

D K Smith

Publications and source records attributed to D K Smith.

134 records · Page 8Linked to original sources
PubMedDate not supplied

MRI of the wrist.

In the past, the diagnostic imaging algorithm for evaluating the painful wrist included initial plain radiographic examination followed by arthrography, tomography, bone scintigraphy, or computed tomography. In recent years, magnetic resonance imaging (MRI) has been proven efficacious for diagnosing a number of maladies of the bones, ligaments, and soft tissues. MRI can be of aid in evaluation of carpal instability, disorders of the triangular fibrocartilage, ulnar impaction syndrome, distal radioulnar joint (DRUJ) instability, fracture, avascular necrosis (AVN), tendinopathy, nerve entrapment syndromes, synovial abnormalities, and soft tissue masses.

Carpal Bones↗
PubMedDate not supplied

Validation of three-dimensional reconstructions of knee anatomy: CT vs MR imaging.

This is the first investigation to validate the accuracy of spatial measurements based on computer-generated three-dimensional (3D) reconstructions of CT and magnetic resonance (MR) scans. Standard 3D reconstructions of one fresh frozen cadaveric knee specimen with implanted stereotactic reference markers were created. These reconstructions were based on the data from CT and MR scans performed before and after the resection of extraosseous soft tissues. The distances between the stereotactic reference markers in the 3D reconstructions were compared with the same measurements of the specimen using a Bridgeport milling machine as a precision 3D digitizer. The accuracy of intermarker distance measurements averaged 99% for CT-based reconstructions compared with 97.5% for MR-based reconstructions. Planar slices at a predetermined level and orientation through the femoral condyles were created by sequential milling of the specimen and were compared with reconstructed oblique planar CT and MR slices at the same level and orientation. The accuracy of condylar dimensional measurements was 94% for CT and 93% for MR compared with measurements of the milled slices. Three-dimensional reconstructions based on CT and MR scan data were of equally high quality and were unaffected by the status of the soft tissues.

Computer Simulation↗
PubMedDate not supplied

Meniscal repair in the goat model. The use of healing adjuncts on central tears and the role of magnetic resonance arthrography in repair evaluation.

We evaluated the effect of adjunctive healing measures on central tears of the adult goat medial meniscus and the role of magnetic resonance arthrography in the assessment of menisci that have undergone a repair. Peripheral tears were made unilaterally in the medial menisci of seven goats in Group I and repaired with nonabsorbable suture. Six Group II goats had central medial meniscal tears repaired as in Group I plus an exogenous fibrin clot. Eight Group III goats had central tears plus abrasion of the parameniscal synovium and tear edges. Six months after surgery, a magnetic resonance imaging scan and a magnetic resonance arthrogram were obtained and the menisci were examined grossly. Group I goats showed healing in all seven knees. Central tears repaired with a fibrin clot (Group II) showed healing in one of six knees (17%). Central tears repaired with abrasion (Group III) showed healing in seven of eight knees (87.5%). Magnetic resonance arthrography was 100% accurate in detecting the presence or absence of complete residual tears. This study supports the current trend of using adjunctive measures for repair of central tears. Furthermore, abrasion of the parameniscal synovium and the tear edges appears to be more effective than the use of an exogenous fibrin clot. Magnetic resonance arthrography is useful in the evaluation of menisci that have undergone repair.

Animals↗
PubMedDate not supplied

Fear of death, death attitudes, and religious conviction in the terminally ill.

The way in which an individual's belief system about death affects fear of death (FOD) has been largely neglected in the thanatology literature. The present study addresses the dimension of certainty or uncertainty with which beliefs about death are held and examines the way in which such attitudes might affect the FOD in dying patients. Twenty terminally ill patients were administered three FOD measures and a death perspective scale which assessed eight death attitudes. FOD among the terminally ill at both the conscious and fantasy level was low. Increased age was associated with declining conscious FOD, independent of life expectancy. Of the eight death perspectives, the attitudes toward death as afterlife-of-reward most directly tap the dimension of certainty or uncertainty. A significant curvilinear relationship emerged between this death perspective and FOD, suggesting that beliefs are a less critical determinant of death fear than is the certainty with which these beliefs are held. The study raises research and clinical issues pertinent to understanding FOD in dying patients.

Adult↗
PubMedDate not supplied

Host genes and HIV: the role of the chemokine receptor gene CCR5 and its allele.

Since the late 1970s, 8.4 million people worldwide, including 1.7 million children, have died of AIDS, and an estimated 22 million people are infected with human immunodeficiency virus (HIV)(1). During 1995 and 1996, major clinical and laboratory discoveries regarding HIV pathogenesis provided new hope for the prevention and treatment of HIV infection. One major discovery was that members of the chemokine receptor family serve as cofactors for HIV entry into cells. We describe the role of allelic polymorphism in the gene coding for the CCR5 chemokine receptor with regard to susceptibility to and disease course of HIV infection. We also examine the effect of this discovery on medical and public health practices.

Adult↗
PubMedDate not supplied

The discipline of teams.

Groups don't become teams because that is what someone calls them. Nor do teamwork values by themselves ensure team performance. So what is a team? How can managers know when the team option makes sense and what they can do to ensure team success? In this article, drawn from their recent book The Wisdom of Teams, McKinsey partners Jon Katzenbach and Douglas Smith answer these questions and outline the discipline that makes a real team. The essence of a team is shared commitment. Without it, groups perform as individuals; with it, they become a powerful unit of collective performance. The best teams invest a tremendous amount of time shaping a purpose that they can own. The best teams also translate their purpose into specific performance goals. And members of successful teams pitch in and become accountable with and to their teammates. The fundamental distinction between teams and other forms of working groups turns on performance. A working group relies on the individual contributions of its members for group performance. But a team strives for something greater than its members could achieve individually. In short, an effective team is always worth more than the sum of its parts. Katzenbach and Smith identify three basic types of teams: teams that recommend things--task forces or project groups; teams that make or do things--manufacturing, operations, or marketing groups; and teams that run things--groups that oversee some significant functional activity. For managers, the key is knowing where in the organization real teams should be encouraged. Team potential exists anywhere hierarchy or organizational boundaries inhibit good performance.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficiency↗
PubMedDate not supplied

Lipid and lipoprotein levels in adults receiving Liposyn II.

Lipid and lipoprotein levels were measured in 45 adult patients receiving parenteral nutrition for 10-14 days who were administered 20-50% of their daily total calorie requirement as Liposyn II. The study was an unblinded noncomparative multicenter investigation. Measurements were made on days 1, 3, 7, 10, and 14. Patients gained an average of 1.2 +/- 0.5 kg body wt during the study. No patient had to be removed from the study due to clinically significant adverse effects. Some changes in hematology, blood chemistry, and liver function parameters occurred, but these changes were consistent with alterations typically observed in patients receiving total parenteral nutrition. Total protein levels increased by an average of 0.30 +/- 0.13 g/dl (p less than 0.03). Plasma levels of phospholipid, triglycerides, total free fatty acids, very-low-density lipoprotein (VLDL) cholesterol and high-density-lipoprotein (HDL) cholesterol were normal or below normal at all times and did not change during the study. Significant increases occurred in total cholesterol (p less than 0.03) and low-density-lipoprotein (LDL) cholesterol (p less than 0.02) that were consistent with the mobilization of tissue cholesterol during intravenous lipid infusions. These increases do not infer any increased risk of coronary heart disease. The ratio of HDL to LDL cholesterol was 0.24-0.28 at all times.

Adult↗