PubMed Health⌕ Search

Biomedical subjects

J M Mack

Publications and source records attributed to J M Mack.

14 recordsLinked to original sources
PubMed1993

Managed care relationships from the physician's perspective.

In response to health care reform proposals as well as health plans, hospitals and individual physicians are affiliating into models that will favorably position them in the evolving managed care marketplace. The development of integrated delivery vehicles requires a merging of physician and hospital cultures. To manage this process the relationship between hospitals and physicians must receive the greatest attention. This chapter describes physician perceptions of specific aspects in the evolving managed care marketplace. Understanding reactions to various initiatives will enable readers to overcome resistance to change and improve their managed care relationships with physicians.

Hospital-Physician Joint Ventures↗
PubMed1989

Nuclear medicine studies of aging--VII. Humeral deltoid tuberosity on bone scans and radiographs.

Because of the occasional finding of increased deposition of bone imaging agent in the area of the humeral deltoid tuberosity, we analyzed both bone scans and radiographs to determine if there were age related correlations. Only 29% of patients of age 35 years or younger showed any radiographic evidence of deltoid tuberosity. This increased to 48% in the 36-64 y age group (and 46% in those of age 65 y and above). Bone scans (99mTc-MDP) of the humerus showed that 26% of individuals of ages 20-39 y had increased uptake in the deltoid tuberosity area. The figure was 21% of those in the 85-94 y age group. However, distribution between sexes in the 20-39 y age cohort was asymmetric (44% of males showed the bone scan finding, but only 15% of the females). We then reviewed cases that had shown the most prominent deltoid tuberosity on humeral radiographs. Thirteen of the 14 cases (93%) were males. Deposition of bone imaging agent in the deltoid tuberosity region was thus only slightly correlated with age (more common after age 35 y), but strongly correlated with sex (males more common) in all three major age groups (35 and under, 36-64, and 65 years and over). Possible interrelations with bone size and muscle mass were pointed out.

Adult↗
PubMed1989

Two false-negative results using morphine sulfate in hepatobiliary imaging.

Morphine sulfate has been used in hepatobiliary imaging to cause contraction of the sphincter of Oddi, thereby increasing pressure in the biliary tree. If the cystic duct is patent, the increased pressure usually causes bile to flow into the cystic duct with filling of the gallbladder. Using this technique, the authors have encountered two false-negative cases. Both patients received 0.04 mg/kg of morphine sulfate intravenously, 40 minutes after the intravenous administration of 5 mCi of technetium 99m-DISIDA. Although both patients filled their gallbladders within 1 hour, they both underwent surgical exploration because of high clinical suspicion of acute cholecystitis. Both were found to have acute cholecystitis.

Biliary Tract↗
PubMed1988

Delayed accumulation (flip flop) of Tc-99m DTPA in a leiomyosarcoma.

An 85-year-old woman with leiomyosarcoma occupying the abdominopelvic area had a renal dynamic study with Tc-99m DTPA. The tumor area initially showed almost no content of the radiopharmaceutical. At 24 hours, there was retention of activity in the leiomyosarcoma as compared with surrounding tissues (flip flop). It was noted that, based on literature reports, tumors of mesodermal origin (leiomyoma, spindle cell sarcoma, neurofibroma) may have the ability to concentrate Tc-99m DTPA.

Aged↗
PubMed1987

Recovery of femoral head perfusion after drainage of septic joint.

A 64-year-old woman was febrile and had pain near the right hip. Blood cultures grew beta hemolytic streptococci. A bone scan showed reduced activity in the right femoral head and neck compared with the left femoral head and neck. She was treated with intravenous antibiotics and surgical decompression of a tense and bulging right hip joint. Five days later, a repeat bone scan revealed much of the femoral head activity to have returned. By day 20 after the initial bone image, there was intense activity throughout the femoral head and neck. Prompt relief of a distended hip joint can result in reperfusion of the femoral head and neck.

Arthritis, Infectious↗
PubMedDate not supplied

Are open-ended or point-of-service plans right for you?

Open-ended and point-of-service plans are relatively new methods of financing and delivering health care, writes Joseph Mack, M.P.A. He describes both plans in detail, along with the operational aspects of a medical group's involvement in such arrangements.

Group Practice↗
PubMedDate not supplied

Circadian disruption and surgical recovery.

Circadian rhythms were investigated in rats following surgery, as measured by body temperature and locomotor activity, and postoperative recovery was measured by activity level. Eight randomly selected Sprague-Dawley rats were implanted with radio temperature-transmitters under general anesthesia. Timer-controlled cassette recorders recorded body temperature at predetermined intervals. To monitor activity, the rats were placed in individual metabolic cages equipped with infrared-sensitive locomotor activity monitors. Temperature was sampled hourly. Activity was measured continuously and summed every 15 minutes for sampling. Measurement was begun before surgery and continued from 12 to 20 days following surgery, depending on when the animals regained their typical rhythmic patterns. Temperature and activity rhythms were altered and uncoupled from external cues in a manner similar to that previously found in humans. The animals demonstrated individual variation in their return to presurgical activity levels. Six days after surgery, the rats experienced a second period of disrhythmic and decreased activity. Rats with the greatest activity phase-shifts took longest to return to presurgical activity levels. This suggests that the degree of circadian alteration following surgery is positively related to the time required for recovery and reentrainment of rhythmicity.

Animals↗