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41.
The initial results from a diagnostic breast clinic in which clinical examination, x-ray mammography and ultrasound are used to establish a diagnosis during a single patient-visit are described. In 3461 patient-visits, 82 histologically-proven breast cancers were detected. Fifty-two per cent of these cancers were 2 cm or less in diameter and 61% had no axillary lymph-node metastases. Fifteen cancers were impalpable lesions which were detected by mammography alone. The over-all malignant-to-benign biopsy ratio was 1:2.7; for impalpable tumours, this ratio was 1:3.9. The role of such a diagnostic breast clinic is discussed, and attention is drawn to a relatively low attendance of women in the "high-risk" age group of over 50 years of age.  相似文献   
42.
Increasing extraocular muscle length by regenerative growth has been proposed as a potentially useful means of treating patients with paralytic or multiple re-operation strabismus. This study evaluates the viability and pattern of regeneration of fresh, autologous extraocular muscle and temporalis muscle transplants in the canine orbit. Bilateral grafts of either inferior oblique or temporalis muscle were sewn between host lateral rectus muscles and the globe. Grafts were biopsied and examined by light and electron microscopy at survival times to 56 days. Functional responses to abducens nucleus stimulation were examined in one extraocular muscle and one temporalis muscle graft at 15 weeks post-operatively. During the first week, both graft types were characterized by loss of pre-terminal nerve from neuromuscular junctions, muscle fiber necrosis that spared the central fibers, and inflammatory cell infiltrate. Myoblasts migrated into and fused within the existing basal laminae of degenerating fibers. By 14 days, grafts were populated by immature myofibers. Neuromuscular junctions were seen by 56 days, coinciding with muscle fiber differentiation as seen by enzyme histochemistry. Only two grafts failed to show regeneration. At 15 weeks survival, both types of grafts contracted in response to abducens nucleus stimulation. Free skeletal muscle grafts to extraocular muscle survive and mature with clear evidence of contractility by 15 weeks. These data suggest that muscle graft procedures could be useful in the management of certain types of strabismus where greater muscle length is needed.  相似文献   
43.
Major differences exist among states in the level of spending on mental health care, in the magnitude and direction of changes in those levels, and in the share of resources devoted to state hospital and community-based services. Using data collected by the National Association of State Mental Health Program Directors (NASMHPD) Research Institute, this article describes those differences and examines their relation to a set of state-level fiscal determinants of mental health spending. Levels of spending in 1990 and rates of change in those levels between 1985 and 1990 show virtually no correlation. Changes in spending between 1985 and 1990 are decomposed into several components. States with high growth tend to have high growth in tax capacity and high growth in mental health spending as a share of health and welfare spending.  相似文献   
44.
Multiple gamma c-dependent cytokines regulate T-cell development   总被引:7,自引:0,他引:7  
Mutations in the common gamma chain (gamma c) of cytokine receptors account for human X-linked severe combined immunodeficiency disease. gamma c contributes to ligand binding and signaling as a component of five cytokine receptors: interleukin-2-receptor (IL-2R), IL-4R, IL-7R, IL-9R and IL-15R. Here, Thomas Malek and colleagues discuss the contribution of individual gamma c-dependent cytokines in both conventional and intraepithelial T-cell development.  相似文献   
45.
Scully C  Porter S 《Dental update》1999,26(6):254-259
Certain lesions are exclusively or typically found in specific sites; these are discussed in this and the next two articles in this series.  相似文献   
46.
Laparoscopic splenectomy in patients with hematologic malignancies   总被引:2,自引:0,他引:2  
BACKGROUND: Although laparoscopic splenectomy (LS) for benign hematologic disease is well accepted, its role in hematologic malignancies is not clearly defined. This study examined the efficacy and feasibility of LS for hematologic malignancies. METHODS: Records were reviewed from patients who underwent LS at two university hospitals. Charts from 77 open splenectomies for malignancy (OM) during the same period were also reviewed. RESULTS: Fifty-three patients underwent LS, 22 for hematologic malignancies (LM) and 31 for benign hematologic disorders (LB). Median splenic weight was greater in the LM group (930 g) than in the LB group (164 g, P = 0.001). LM was associated with longer operations and greater blood loss than was LB. LM had a 41% conversion rate. Morbidity, mortality, and transfusion rates were similar. Median hospital stay was shorter for LM (4 days) than for OM (6 days, P = 0.001). CONCLUSIONS: LS is feasible in hematologic malignancies but is associated with increased operative time and blood loss and a high conversion rate. Morbidity and mortality, however, was similar. Shorter hospital stays for LM compared with OM may translate into earlier recovery and initiation of antineoplastic therapy.  相似文献   
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BACKGROUND: The authors used a nursing task inventory system to assess nursing resources for patients with and without adverse postoperative events in the postanesthesia care unit (PACU). METHODS: Over 3 months, 2,031 patients were observed, and each task/activity related to direct patient care was recorded and assigned points according to the Project Research in Nursing (PRN) workload system. PRN values for each patient were merged with data from an anesthesia database containing demographics, anesthesia technique, and postoperative adverse events. Mean and median PRN points were determined by age, sex, duration of procedure, and mode of anesthesia for patients with and without adverse events in the PACU. Three theoretical models were developed to determine the effect of differing rates of adverse events on the requirements for nurses in the PACU. RESULTS: The median workload (PRN points) per patient was 31.0 (25th-75th percentile, 25-46). Median workload was 26 points for patients with no postoperative events and 155 for > or = six adverse events. Workload varied by type of postoperative event (e.g., unanticipated admission to the intensive care unit, median workload = 95; critical respiratory event = 54; and nausea/vomiting = 33). Monitored anesthesia care or general anesthesia with spontaneous ventilation used less resources compared with general anesthesia with mechanical ventilation. Modeling various scenarios (controlling for types of patients) showed that adverse events increased the number of nursing personnel required in the PACU. CONCLUSIONS: Nursing care documentation based on requirements for individual patients demonstrates that the rate of postoperative adverse events affects the amount of nursing resources needed in the PACU.  相似文献   
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