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Biomedical subjects

W Kim

Publications and source records attributed to W Kim.

At least 199 records · Page 11Linked to original sources
PubMed1988

Pulmonary arteriovenous malformations: techniques and long-term outcome of embolotherapy.

Over a 10-year period, 276 pulmonary arteriovenous malformations (PAVMs) were occluded with balloon embolotherapy in 76 patients, 67 (88%) of whom had hereditary hemorrhagic telangiectasia. Eleven patients (14%) were discovered by means of family screening with measurement of arterial blood gases and chest radiography. Epistaxis, dyspnea, hemoptysis, and hemothorax occurred in 79%, 71%, 13%, and 9% of patients, respectively. Clinical histories of strokes and transient ischemic attacks were present in 18% and 37% of patients, respectively. Computed tomographic scans of 59 patients showed stroke in 36%. Sixty-five percent of PAVMs were located in the lower lobes, which correlated with the finding of more pronounced hypoxemia in the upright position. After embolotherapy, symptomatic hypoxemia was corrected, and serial values have remained constant for 5 years. Complications were minimal, and no patient required surgery. Balloon embolotherapy is effective long-term therapy for PAVMs, and family screening should be pursued because of the possibility of a higher frequency of paradoxical embolization (stroke) than previously recognized.

Adolescent↗
PubMed1988

Quantification of thermal asymmetry. Part 2: Application in low-back pain and sciatica.

Temperature differences between the lower extremities were measured using a computerized thermometric scanning system in order to compare the degree of thermal asymmetry in 144 patients with low-back pain. The patients displayed highly significant thermal asymmetries, with the involved limb being cooler (p less than 0.001). When asymmetries exceeded 1 standard deviation from the mean temperature of homologous regions measured in 90 normal control subjects, the positive predictive value of thermometry in detecting root impingement was 94.7% and the specificity was 87.5%. These values indicate that calculation of temperature asymmetry is particularly effective in evaluating reported pain in psychosocially affected patient populations in whom the chance of positive myelography or impaired root function is low. In this group of patients, thermometric study provides physicians with important information for proper decision making. The test can be performed to avoid more invasive and probably less revealing diagnostic or exploratory surgical procedures.

Adult↗
PubMed1988

Acceptability of a 7-day higher-carbohydrate, lower-fat menu: the Beltsville Diet study.

For 13 weeks, 20 men (aged 23 to 56), 19 premenopausal (aged 21 to 48), and 14 postmenopausal women (aged 49 to 65) consumed a 7-day rotation menu conforming to dietary recommendations of several research and health organizations. The diets were designed to make minimal changes in the standard American diet by the use of well-accepted normal foods. The average daily composition of the diet was 50% carbohydrate (complex 35%, simple 15%), 35% fat (P:S 0.7), and 15% protein; it contained 100 mg cholesterol, 1 gm sodium, and 14.5 gm neutral detergent fiber per 1,000 kcal. The acceptability of the menus was examined through questionnaires administered after the experimental diet period. Subjects rated the menus and individual foods and made recommendations for improvement of the menus. Most subjects (33 of 41 responding) rated the menu better than or almost as good as their usual diet. Few (9) were ever hungry during the 13-week period. During the study, a number of biochemical parameters were measured; the measurements indicated beneficial results. Blood pressure, cholesterol levels, and glucose responses were all improved after consumption of the menu. The results indicate that with minimal changes in the normal U.S. diet, acceptable menus that have beneficial effects on risk factors for heart disease and diabetes can be developed.

Adult↗
PubMed1984

Treatment of primary osteoarthritis of the hip. A comparison of total joint and surface replacement arthroplasty.

Of 285 total hip arthroplasties (260 patients) performed for primary osteoarthritis during a six-year period, 135 were resurfaced using a Tharies prosthesis (total hip articular replacement with internal eccentric shells) and 150 were treated with the Trapezoidal-28 total hip replacement. From each of these two groups 100 hips (ninety-one patients in the Tharies group and eighty-six in the Trapezoidal-28 group) that had been followed for two to seven years were evaluated at the time of follow-up in accordance with a predetermined protocol. The patients were younger in the Tharies than in the Trapezoidal-28 group (average ages, fifty-eight and sixty-six years), included more men (sixty compared with thirty-five), and were more active postoperatively. The average follow-up was forty-seven months for the total joint-replacement group and thirty-eight months for the surface replacement group. At follow-up the ratings for pain, walking, and function according to the University of California at Los Angeles 10-point scale and the clinical results were identical in the two groups. Heterotopic ossification (Brooker grade III or IV) developed after thirteen Trapezoidal-28 and twenty-two Tharies arthroplasties. Radiographs made at six and twelve months and at final follow-up showed that the incidence of radiolucencies about the acetabular component was higher in the resurfacing group: fifty-seven with complete radiolucent lines after an average follow-up of thirty-eight months compared with thirty-six with complete lines after an average follow-up of forty-seven months. There were three failures in the joint-replacement group: a hematogenous staphylococcal deep infection that required a Girdlestone procedure, a femoral stem fracture that required revision, and loosening of an acetabular component for which revision was performed. There was also one dislocation, successfully treated by closed reduction. Similarly, in the resurfacing group there were three failures: two loose acetabular components, revised successfully, and one loose femoral component that necessitated total joint arthroplasty. Multivariate stepwise regression analysis showed that the factors that affected the final extent and width of the acetabular radiolucencies adversely after resurfacing were: any radiolucent lines that were visible at six months, a high level of physical activity after arthroplasty, and a thin superior cement mantle.(ABSTRACT TRUNCATED AT 400 WORDS)

Activities of Daily Living↗
PubMed1983

Prosthetic replacement in osteonecrosis of the hip.

The young patient with avascular necrosis of the hip presents one of the unsolved problems in orthopaedics today. Many of these patients are active and have expectations of continuing activities that may be far in excess of reality, considering the results achieved in these patients with replacement arthroplasty. In contrast to this group of patients, the patient with systemic disease has a built-in "brake" and appears to do well with conventional arthroplasty. New fixation techniques are yielding more promising results, and continued research into new modes of fixation such as porous ingrowth may well cast a new light on the problem. At this time, however, the clinician is called on to evaluate not only the disease process but the anticipated continuing activity of the patient. Thus there is no one procedure appropriate for this disease but rather several alternatives, each having its own indication at a specific stage in the disease process.

Adolescent↗
PubMed1983

Bony ingrowth fixation of newly designed acetabular components in a canine model.

Implantation of a newly designed acetabular component with a porous coating has resulted in superior fixation when compared with acrylic cementation in the short term. Experiments in dogs demonstrate rapid ingrowth within the porous layers, resulting in rigid fixation of the acetabular components despite defects in the prepared bony bed. Acute infection prevents bony ingrowth and causes loosening. The absence of any foreign-body response to the titanium fiber mesh components suggests that this is a biocompatible metal. The fixation has been excellent; progressive or delayed loosening is not encountered once successful ingrowth is achieved. Progressive radiolucent zones generally do not appear in the short term but when visible soon after surgery, may consolidate and disappear. Ingrowth fixation of acetabular components appears to offer an attractive alternative to the use of acrylic cement and may even be feasible in patients with periarticular bony abnormalities.

Acetabulum↗
PubMed1981

Hypercalcemia associated with epidermoid carcinoma in ovarian cystic teratoma.

A case of metastatic epidermoid carcinoma arising in benign cystic teratoma of the ovary is reported. The clinical course was complicated by severe hypercalcemia and respiratory distress due to associated diffuse calcification of the lungs. Presumptive evidence is presented to show that prostaglandin E found in the tumor was the cause of the hypercalcemia.

Carcinoma, Squamous Cell↗
PubMedDate not supplied

Prevalence of human foamy virus-related sequences in the Korean population.

The possible association of human foamy virus (HFV) with human thyroid disorders such as Graves' disease (GD) has been a topic of controversy due to the inconsistent results reported by several groups of investigators. Here we report the investigation of the presence of HFV-related sequences in the Korean population. DNA was obtained from peripheral blood lymphocytes from 24 GD patients and 23 healthy blood donors and subjected to PCR amplification using three sets of nested primers derived from gag, env, and LTR regions of the HFV genome. Contrary to previously reported studies, our analysis identified HFV-related sequences in the genomes of both healthy individuals and the GD patients. However, the nature of the HFV genome present in each group appeared to be different. We detected all 3 regions of HFV-related sequences in 29% of the HFV-positive GD patients, while no samples in the control group amplified all three regions. This suggests that the LTR may be used as a tool for screening for HFV in GD patients. Our data favor the hypothesis of a relationship between GD and the presence of HFV-related sequences, though in a complex way.

Adult↗
PubMedDate not supplied

Near-field optical studies of local photomodification in nanostructured materials.

Fractal aggregates of silver nanoparticles are studied experimentally using atomic force microscopy and photon scanning tunnelling microscopy. Large changes in the near-field optical response of fractal aggregates are observed after the irradiation of samples with nanosecond laser pulses. The threshold energy density for photomodification using a 532 nm laser is measured to be 9 mJ cm(-2). It is shown that photomodification-induced changes in the local optical response can be two orders of magnitude larger than changes in far-field absorption.

Journal Article↗
PubMedDate not supplied

Corpus-based statistical screening for phrase identification.

PURPOSE: The authors study the extraction of useful phrases from a natural language database by statistical methods. The aim is to leverage human effort by providing preprocessed phrase lists with a high percentage of useful material. METHOD: The approach is to develop six different scoring methods that are based on different aspects of phrase occurrence. The emphasis here is not on lexical information or syntactic structure but rather on the statistical properties of word pairs and triples that can be obtained from a large database. MEASUREMENTS: The Unified Medical Language System (UMLS) incorporates a large list of humanly acceptable phrases in the medical field as a part of its structure. The authors use this list of phrases as a gold standard for validating their methods. A good method is one that ranks the UMLS phrases high among all phrases studied. Measurements are 11-point average precision values and precision-recall curves based on the rankings. RESULT: The authors find of six different scoring methods that each proves effective in identifying UMLS quality phrases in a large subset of MEDLINE. These methods are applicable both to word pairs and word triples. All six methods are optimally combined to produce composite scoring methods that are more effective than any single method. The quality of the composite methods appears sufficient to support the automatic placement of hyperlinks in text at the site of highly ranked phrases. CONCLUSION: Statistical scoring methods provide a promising approach to the extraction of useful phrases from a natural language database for the purpose of indexing or providing hyperlinks in text.

Abstracting and Indexing↗
PubMedDate not supplied

Joint resurfacing with cartilage grown in situ from cell-polymer structures.

We tested the potential of a new technology developed in our laboratory to create new hyaline cartilage for resurfacing distal femoral joint surfaces of New Zealand White rabbits that had been surgically denuded of articular cartilage. We removed hyaline cartilage from the patellar groove of the distal femurs in 24 rabbits. Chondrocytes isolated from the excised cartilage of 12 of these rabbits (experimentals) were seeded onto synthetic biocompatible, biodegradable polymers composed of polyglycolic acid. The cells were labeled in vitro with a thymidine analog, BrdU (5-bromo-2'-deoxyuridine). After 1 week in vitro, the cell-polymer structures were implanted onto the denuded surfaces of 12 defects made in the hyaline cartilage of the contralateral knees of the experimental animals. Twelve control animals received either no implants or implants not containing cells on similar surgical defects. After 7 weeks, we found evidence of new cartilage growth in 11 of the 12 experimental animals and virtually no new cartilage formation in any of the animals in either control group. Immunohistochemical analysis demonstrated the presence of BrdU-labeled chondrocytes in representative specimens.

Animals↗
PubMedDate not supplied

Antidromic sensory nerve conduction studies of medial and lateral plantar nerves in normals.

A reliable sensory nerve conduction study for the most distal lower extremities is needed in routine clinical electromyography. This paper reports a study of 150 medial and lateral plantar nerves in the foot in normals. An antidromic technique was used with stimulation at the ankle and recording from the small and large toes. Recordable responses were obtained in 149 instances. Conduction velocity in the medial branch distal to the tarsal tunnel was 40.5 +/- 4.0 m/sec and significantly slower than conduction in the lateral branch by 4.3 m/sec. The amplitude of the evoked response from the big toe was 3.46 +/- 2.2 microV and significantly larger than that in the small toe by 1.34 microV. Evoked response amplitude in the medial branch was greater in younger subjects.

Adult↗