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S R Smith

Publications and source records attributed to S R Smith.

At least 253 records · Page 14Linked to original sources
PubMed1989

Semantic abilities in dementia of the Alzheimer type. 1. Lexical semantics.

The lexical semantic abilities of 18 Alzheimer patients were investigated using confrontation naming tasks (including both visual and tactile naming tests) and compared to those of a group of institutionalized, nonneurologically impaired control subjects matched for age, sex, and educational level. The Alzheimer patients produced a greater number of naming errors than the control subjects. The errors made by subjects during the naming tasks were analyzed according to a set of 16 error response types. The Alzheimer patients' response patterns suggest that they do recognize objects which they are unable to name and are able to identify the semantic class to which the target belongs, but cannot provide the lexeme corresponding to the correct individual class member. The results support a semantic network disruption rather than a visual perceptual deficit as the basis of the naming disturbance observed in Alzheimer patients.

Aged↗
PubMed1989

Semantic abilities in dementia of the Alzheimer type. II. Grammatical semantics.

The grammatical semantic abilities of 18 Alzheimer patients were investigated using picture description tasks and compared to those of a group of institutionalized, nonneurologically impaired control subjects matched for age, sex, and educational level. During picture description, Alzheimer patients showed that they were able to provide as much information about the target picture as control subjects, but were less concise in their verbal representation of the information. The lack of conciseness was reflected in the DAT patients requiring more time and more syllables to communicate a similar quantity of information than the control subjects. The appropriateness of using a picture description task which involves a perceptual step-by-step account of unrelated events to assess sentential semantics and the conveying of information at a conceptual level is discussed.

Alzheimer Disease↗
PubMed1989

Nonresurfaced patella in total knee arthroplasty.

Problems attributable to the patellofemoral joint are still the major cause of disability in contemporary knee arthroplasty. Patellar resurfacing does lead to further complications, such as loosening, wear, and malalignment. Two studies have been performed specifically to review experience with the nonresurfaced patella in total knee arthroplasty. The first study determined that patellofemoral symptoms occurred in 8% of the total group and the majority of these were due to patellar malalignment. The postoperative skyline views at 60 degrees and 90 degrees of flexion obtained routinely identified dynamic patellar maltracking responsible for anterior knee pain. The second study addressed long-term durability of the nonresurfaced patella. The tracking of the patella was maintained with only small shifts of patella position and the tendency to stabilize with time. Stress-induced bone remodelling, particularly of the lateral facet, occurred in 85% of patellae. No preoperative or postoperative radiologic variable was associated with anterior knee pain. The authors strongly recommend that accurate patellofemoral tracking be obtained at the time of knee arthroplasty by staged procedures, with removal of peripheral osteophytes, then proximal iliotibial tract release followed by lateral debulking to a marked degree to obtain neutral tracking. Only then will intracapsular lateral release be performed. The results presented support the use of the nonresurfaced patella, and patellar malalignment remains a major source of disability attributable to the patellofemoral joint following total knee arthroplasty.

Arthroplasty↗
PubMed1989

Quantitative magnetic resonance imaging in autologous bone marrow transplantation for Hodgkin's disease.

Fifteen consecutive patients with refractory or relapsed Hodgkin's disease (HD) referred for autologous bone marrow transplantation (ABMT) underwent quantitative magnetic resonance (MR) studies of the lumbar vertebral bone marrow. Markedly elevated lumbar vertebral marrow T1 values suggestive of bone marrow involvement with HD were seen in four patients, two of whom had no evidence of HD on bilateral iliac crest bone marrow biopsy. Serial studies showed normalisation of T1 values in the post-transplant period. T1 relaxation rate correlated positively with time to engraftment following ABMT and a significant correlation (r = 0.73, 0.02 greater than P greater than 0.01) between T2 relaxation rate and granulocyte and macrophage colony forming units (CFU-GM) of processed bone marrow was seen. This preliminary study illustrates the potential role of quantitative MRI both in the pre-transplant assessment of patients considered for ABMT and in the post-transplant evaluation of tumour response when marrow involvement with HD is present.

Adult↗
PubMed1989

An activated form of transforming growth factor beta is produced by cocultures of endothelial cells and pericytes.

Using an in vitro coculture system to mimic the interactions between the cells of the vessel wall, we have previously shown that pericytes and smooth muscle cells (SMC) inhibit the growth of capillary endothelial cells (EC). We have undertaken studies to determine the mechanism of this inhibition. Using conditioned media and affinity-purified antibodies to transforming growth factor beta (TGF-beta), we now demonstrate that activated TGF-beta produced in these cocultures mediates EC growth inhibition. No inhibitory activity was detected when media conditioned by individual cultures of EC, SMC, or pericytes were examined for their effect on EC growth. In contrast, media conditioned by cocultures of EC-SMC and EC-pericytes inhibited EC proliferation to the same degree as the coculture itself. Immunoadsorption of coculture-derived conditioned media with antibodies to TGF-beta eliminated the inhibitory activity. Acid activation of serum-free media conditioned by any of the cells cultured alone yielded inhibitory activity, whereas activation of coculture conditioned media did not increase its inhibitory activity. Addition of anti-TGF-beta neutralizing antibodies to cocultures blocked the pericyte-mediated EC growth inhibition. These results indicate that latent TGF-beta is produced by these cells and it is activated by a mechanism that requires contact between the two cell types.

Animals↗
PubMed1989

A comparison of the effects of flosequinan, a new vasodilator, and propranolol on sub-maximal exercise in healthy volunteers.

1. The effects of steady state flosequinan, a new vasodilator, and propranolol, on glucose mobilisation, lipolysis and plasma potassium concentration during sub-maximal exercise testing were investigated in a double-blind, randomised, three-way crossover study in 12 healthy volunteers. 2. Plasma glucose, potassium and free fatty acid concentration during and after exercise on flosequinan were similar to those on placebo. Exercise heart rates were 7% (+9.2 beats min-1) higher on flosequinan compared with placebo (P less than 0.05). During exercise on propranolol plasma glucose concentrations were comparable with those on placebo but plasma potassium concentrations were higher (mean increase 0.26 mmol l-1, P less than 0.01) whereas free fatty acid concentrations were lower (mean decrease 0.10 mmol 1-1, P less than 0.01). As expected the heart rate on exercise was 25% less (-35 beats min-1) on propranolol (P less than 0.05). 3. These data suggest that, in contrast to propranolol, flosequinan does not adversely affect the mobilisation of the two major sources of energy during sub-maximal exercise.

Adolescent↗
PubMed1989

Randomized prospective study comparing vancomycin with teicoplanin in the treatment of infections associated with Hickman catheters.

In 72 episodes of suspected or proven Hickman-catheter-associated infection occurring in 59 patients with various hematological disorders, patients were assigned to treatment with either vancomycin or teicoplanin in a randomized nonblinded prospective study. Of 60 episodes evaluable for response, 28 were treated with vancomycin and 32 were treated with teicoplanin. Sixteen infective episodes were microbiologically documented in the vancomycin group, and twenty-one were microbiologically documented in the teicoplanin group. Microbiologically and clinically documented infections treated with vancomycin had an 80% response rate, compared with a 69% response rate for those treated with teicoplanin (P = 0.316). Adverse events occurred in nine (25%) of the episodes in the vancomycin group, compared with three (8%) in the teicoplanin group (P = 0.044). Teicoplanin may provide an effective alternative to vancomycin in the treatment of Hickman-catheter-associated infection in patients with hematological malignancies.

Adolescent↗
PubMed1989

Bone marrow disorders: characterization with quantitative MR imaging.

Thirty patients with various hematologic disorders and 15 healthy control subjects underwent quantitative magnetic resonance (MR) imaging of the lumbar spine with spin-echo techniques. Images of patients with infiltrative bone marrow disorders showed significantly more prolonged T1 times than those of control subjects (P less than .001). It was not possible to distinguish different diffuse infiltrative bone marrow disorders on the basis of T1 values. Aplastic anemia could be distinguished from normality because of significantly shortened T1 (P less than .001). A significant correlation was seen between T1 and bone marrow cellularity (r = .74, P less than .001). T2 was of no value in the characterization of bone marrow disorders. Quantitative MR imaging dose not improve the diagnostic potential of bone marrow imaging in the detection of diffuse marrow infiltrates.

Adult↗
PubMed1989

Abolition of in vivo platelet thrombus formation in primates with monoclonal antibodies to the platelet GPIIb/IIIa receptor. Correlation with bleeding time, platelet aggregation, and blockade of GPIIb/IIIa receptors.

We studied the dose-response effects of the F(ab')2 fragments of murine monoclonal antibodies to the platelet GPIIb/IIIa receptor (7E3 and 10E5) on in vivo platelet thrombus formation in a well-characterized monkey model in which the carotid artery is stenosed and thrombus formation is provoked and augmented by intimal damage and the infusion of subaggregating doses of epinephrine. Both antibodies abolished thrombus formation with a mean dose of -0.2 mg/kg. Ex vivo platelet aggregation was not always abolished at doses that abolished thrombus formation; similarly, bleeding times were only moderately prolonged (9.1 +/- 1.4 minutes) at these doses. Increasing the dose above that required to abolish thrombus formation consistently produced abolition of ex vivo platelet aggregation, marked prolongation of the bleeding time (14.2 +/- 1.5 minutes), and nearly quantitative blockade of GPIIb/IIIa receptors. We conclude that in a significant percentage of animals, the extent of GPIIb/IIIa blockade required to prevent vasoocclusive thrombus formation in this model is less than that required for abolition of platelet aggregation, and that the preservation of only a minority of functional GPIIb/IIIa receptors might be adequate to maintain a nearly normal bleeding time.

Animals↗
PubMed1989

Wilms tumor (nephroblastoma) in the adult patient: clinical and radiologic manifestations.

Wilms tumor (nephroblastoma), a primary renal neoplasm containing primitive blastema and embryonic glomerulotubular structures, is seen rarely in adults. To identify clinical and radiologic criteria for preoperative diagnosis of adult Wilms tumor, we studied 29 cases reported in the literature from 1975 to 1987 (all patients were 15 years old or older) and four newly diagnosed cases. The mean age of patients was 30 years; 80% were less than 35 years old. Each patient presented with a large, rapidly growing, abdominal mass (average duration of symptoms, less than 2 months), had no constitutional symptoms (e.g., weight loss, fever), and otherwise were healthy (80%). Twenty-six patients had IV or retrograde pyelograms. Twenty-three showed a nonspecific mass effect. In seven (78%) of nine patients, abdominal CT scans showed a large, inhomogeneous mass with large areas of low density and increased enhancement of the compressed remaining normal renal parenchyma, which resembled a pseudocapsule. In five (63%) of eight patients, sonograms showed a complex mass with large cystic components. In 18 (82%) of 22 patients, arteriograms showed a hypovascular mass with fine wavy or zigzag (creeping-vine) neovascularity. We conclude that a rapidly growing renal mass in a young patient (less than 35 years old) that is shown to be complex and cystic by CT or sonography and that is hypovascular with fine, wavy neovascularity on arteriography is suggestive of adult Wilms tumor (75-80%). An awareness of this constellation of findings may be helpful in diagnosing this unusual tumor before surgery.

Adolescent↗
PubMed1989

Situational theory of leadership.

The situational theory of leadership and the LEAD instruments for determining leadership style are explained, and the application of the situational leadership theory to the process of planning for and implementing organizational change is described. Early studies of leadership style identified two basic leadership styles: the task-oriented autocratic style and the relationship-oriented democratic style. Subsequent research found that most leaders exhibited one of four combinations of task and relationship behaviors. The situational leadership theory holds that the difference between the effectiveness and ineffectiveness of the four leadership styles is the appropriateness of the leader's behavior to the particular situation in which it is used. The task maturity of the individual or group being led must also be accounted for; follower readiness is defined in terms of the capacity to set high but attainable goals, willingness or ability to accept responsibility, and possession of the necessary education or experience for a specific task. A person's leadership style, range, and adaptability can be determined from the LEADSelf and LEADOther questionnaires. By applying the principles of the situational leadership theory and adapting their managerial styles to specific tasks and levels of follower maturity, the authors were successful in implementing 24-hour pharmacokinetic dosing services provided by staff pharmacists with little previous experience in clinical services. The situational leadership model enables a leader to identify a task, set goals, determine the task maturity of the individual or group, select an appropriate leadership style, and modify the style as change occurs. Pharmacy managers can use this model when implementing clinical pharmacy services.

Behavior↗
PubMed1988

Traumatic retroperitoneal venous haemorrhage.

Vena caval injury is rare in the UK, but changes in society suggest that it may become more frequent. The problem is always unexpected and presents a major surgical challenge. Modern techniques have led to a substantial improvement in survival so that most patients with an infrarenal injury should now survive but only with prompt, effective treatment. In this review the problems and techniques of surgical management are illustrated by three cases of traumatic injury and two of peroperative accidents.

Adult↗
PubMed1988

Abdominoperineal and anterior resection of the rectum with retrocolic omentoplasty and no drainage.

Forty consecutive patients scheduled for either low anterior resection or abdominoperineal resection of the rectum have been studied. After standard procedures, carried out by all grades of surgeons, the omentum was mobilized as a pedicle graft based on the left gastro-epiploic arcade and transposed to the pelvis or perineum. All wound were closed primarily without drainage. Twenty-six patients had anterior resection, 11 abdominoperineal resection and 3 an extended Hartmann's operation. Patients were assessed clinically and radiographically by Gastrografin enema and ultrasound for evidence of anastomotic leakage, pelvic collections and wound healing. After anterior resection there were three radiological leaks and no overt clinical leaks. One patient had a collection related to a leak. Of 11 perineal wound 8 healed primarily in 2 weeks and all healed by 4 weeks. There was no frank wound breakdown. The three patients who had Hartmann's operations all healed without complication. There were no unavoidable complications of the procedure. Retrocolic omentoplasty is a simple, safe and effective adjunct to rectal surgery. The additional time taken (15-20 min) is well rewarded by sound healing of these operations.

Aged↗