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1.
2.
The Usefulness of Magnetic Resonance Imaging in the Diagnosis of Anterolateral Impingement of the Ankle 总被引:3,自引:0,他引:3
LCDR Doug Duncan MD CAPT Tim Mologne MD CDR Hans Hildebrand MD Mark Stanley MD LT Richard Schreckengaust MD CAPT Dave Sitler MD 《The Journal of foot and ankle surgery》2006,45(5):304-307
The purpose of this study is to assess the sensitivity and specificity of magnetic resonance imaging (MRI) in the diagnosis of anterolateral impingement of the ankle and to assess the most helpful sequence in making the diagnosis. Twenty-four patients who had undergone ankle arthroscopy were chosen. Twelve patients had arthroscopically documented anterolateral impingement, and 12 patients with no impingement on arthroscopy served as controls. Two musculoskeletal radiologists and an orthopedic surgeon, blinded to the operative diagnosis, retrospectively reviewed selective MRI images in the sagittal, axial, and coronal planes. The sensitivities and specificities were calculated for all 3 reviewers. The Kendall coefficient of concordance was calculated for overall agreement among reviewers. Sensitivities varied from 0.75 to 0.83, whereas specificities varied from 0.75 to 1.00. Using the Fisher exact test of contingency, the sensitivities and specificities showed that all reviewers' interpretations were statistically significant with P = .039, .001, and .012, respectively. The axial images were felt to be most helpful in making the diagnosis. The physicians felt that the sagittal images were helpful in 67%, 83%, and 100%, respectively. MRI is a useful tool that can aid the clinician in the diagnosis of anterolateral impingement of the ankle. T1 sagittal images demonstrating displacement of the normal fat signal anterior to the fibula by scar can be useful and help to confirm the diagnosis. 相似文献
3.
Diane M. Burnard Quentin J. Pittman Brian A. MacVicar 《Journal of neuroendocrinology》1991,3(4):433-439
Intracellular recordings were obtained from pituicytes in the neural lobe of the isolated rat pituitary. Like other glia, pituicytes lacked action potentials in response to depolarizing current injection, but they tended to have more positive resting membrane potentials and higher input resistances than astrocytes in other preparations. Dye-coupling typical of astrocytes was also demonstrated amongst pituicytes, and their morphologies were similar to those of pituicytes stained for glial fibrillary acidic protein. Action potentials, anode-break spikes or barium spikes were not observed in pituicytes, even under conditions that maximized the elicitation of Ca2+-dependent responses. This suggests that pituicytes either have no or a very low density of Ca2+ channels or Ca2+ currents that are too small to generate action potentials. Dynorphin A (1–13), a kappa-opioid agonist, produced long-lasting increases in pituicyte input resistance with no significant changes in resting membrane potential. Dynorphin's action was concentration-dependent and was blocked by the opioid antagonist naloxone. This is consistent with previous reports demonstrating kappa-opioid receptors on pituicytes in the neurohypophysis. The β-adrenergic agonist isoproterenol (100 μM) reversed the increases in pituicyte input resistance produced by opioid application, with no significant changes in resting membrane potential. The fact that pituicytes responded to neurotransmitters suggests a functional link between pituicytes and neurosecretory nerve fibres. 相似文献
4.
Creating empowering meaning: an interactive process of promoting health with chronically ill older Canadians 总被引:2,自引:1,他引:1
McWilliam C; Stewart M; Brown J; McNair S; Desai K; Patterson M; Del Maestro N; Pittman B 《Health promotion international》1997,12(2):111-123
Many health promotion approaches afford education about disease prevention
and enhancement of one's health status. But strategies for enabling older
people with chronic illness to better mobilize their resources for everyday
living still require development. This practical action research study
explored the experiences of 13 purposefully selected older persons who
participated in a health promotion intervention premised on the adult
education theory of perspective transformation. Findings illuminate health
promotion through a holistic interactive process in which professional and
chronically ill older person together evolved a caring relationship and
enhanced conscious awareness of life and health experiences. Five
health-promoting strategies were identified: building trust and meaning;
connecting; caring; mutual knowing; and mutual creating. Researchers
suggest several important directions to refine professional practice
approaches and health care delivery systems in order to promote the health
of older persons with chronic conditions. 相似文献
5.
Prevention of arginine-vasopressin-induced motor disturbances by a potent vasopressor antagonist 总被引:2,自引:0,他引:2
The antivasopressor analog d(CH2)5Tyr(Me) arginine-vasopressin completely blocked the convulsive-like behavior and other severe motor disturbances which are normally observed following a second central arginine-vasopressin injection. This vasopressor antagonist appears to be selective for arginine-vasopressin-induced motor disturbances, in that the convulsive and motor effects of pentylenetetrazol and somatostatin were not altered significantly by pretreatment with the central antagonist. Results suggest that arginine-vasopressin-induced motor disturbances are mediated via central receptors. The classic antidiuretic (V2) type of arginine-vasopressin receptor does not appear to be involved, since the agonist 1-desamino-8-D-arginine-vasopressin did not elicit convulsive-like behavior or other severe motor disturbances 2 days following a first ('priming') injection of arginine-vasopressin. 相似文献
6.
Miriam Stewart Linda Reutter Edward Makwarimba Irving Rootman Deanna Williamson Kim Raine Doug Wilson Janet Fast Rhonda Love Sharon McFall Deana Shorten Nicole Letourneau Karen Hayward Jeff Masuda William Rutakumwa 《Revue canadienne de recherche en sciences infirmières》2005,37(3):104-131
Poverty influences health status, life expectancy, health behaviours, and use of health services. This study examined factors influencing the use of health-related services by people living in poverty. In the first phase, 199 impoverished users of health-related services in 2 large Canadian cities were interviewed by their peers. In the second phase, group interviews with people living in poverty (n = 52) were conducted. Data were analyzed using thematic content analysis. Diverse health-related services were used to meet basic and health needs, to maintain human contact, and to cope with life's challenges. Use of services depended on proximity, affordability, convenience, information, and providers' attitudes and behaviours. Use was impeded by inequities based on income status. To promote the health of people living in poverty, nurses and other health professionals can enhance the accessibility and quality of services, improve their interactions with people living in poverty, provide information about available programs, offer coordinated community-based services, collaborate with other sectors, and advocate for more equitable services and policies. 相似文献
7.
Elevated serum sodium and potassium levels were recently observed when sampled through a heparin-bonded umbilical catheter and measured with certain ion-selective electrodes. The cationic surfactant, benzalkonium chloride (BZC), is known to falsely elevate those cations in serum. Inasmuch as most heparin-bonded umbilical catheters use BZC during the bonding process, an in vitro study was performed to estimate the quantity of BZC released and the duration of sodium and potassium elevations during pooled sera infusion. Three heparin-bonded umbilical catheters and 3 silastic umbilical catheters were first flushed with 0.3 mL of normal saline and then perfused with pooled sera (sodium, 142 mEq/L; potassium, 4.6 mEq/L) at 2.5 microL/h. Effluent samples were collected from 0 to 8 hours and analyzed by ion-selective electrodes. Elevated serum sodium concentrations from 160 to greater than or equal to 250 mEq/L and potassium concentrations from 6.0 to greater than or equal to 9.6 mEq/L were observed. The BZC concentration in the catheter effluent was measured by mass spectrometry, with peak values of 10 micrograms/mL detected by this method. When varying concentrations of BZC (1 to 100 micrograms/mL) were added directly to pooled serum, a dose-dependent increase in serum sodium was observed. These data demonstrate that BZC released from heparin-bonded umbilical catheters elevates serum electrolyte values measured with some ion-selective electrodes. The observed increase in sodium and potassium concentrations may lead to clinical errors in management. Benzalkonium chloride is associated with myriad of linical symptomatology. Whether this amount of BZC is toxic in the small premature neonate is presently unknown. 相似文献
8.
Doug Joshua Max Wolf Jane Matthews Lee Tan William Sheridan Glenn Pilkingtonh Fiona Page 《Leukemia & lymphoma》1994,14(3):303-309
The Australian Leukaemia Study Group myeloma study (MM1) aimed to determine the prognostic significance of clinical and immunophenotypic markers in patients with multiple myeloma. All patients were treated with standard dose melphalan and prednisone. Seventy-four patients were entered and the median survival was 27 months. Serum beta 2-microglobulin (βM) and albumin levels were the only significant clinical factors influencing survival (p = 0.007 and p = 0.008, respectively). Patients with raised levels of CD38+ lymphocytes at presentation had a significantly shorter survival than patients with normal levels (p = 0.01, logrank test, median 19 months vs 33 months). CD38 antigen expression was independent of β2M but patients with raised levels of CD38 had significantly lower levels of albumin than patients with normal levels (p = 0.001) which may explain their poorer survival. Salmon and Durie stage was not associated with antigen expression. No other B-cell antigens (CD10, CD19, CD20, CD21, CD22, CD23, FMC1 or FMC7) or plasma cell antigens tested (PCA-1) were found to be associated with prognosis. Patients who achieved plateau phase had a better prognosis than those who did not (p = 0.04 in a landmark analysis). Patients who achieved plateau phase following an objective response appeared to have a better prognosis than those who were in plateau phase at presentation (p = 0.09 in a landmark analysis). Light chain isotype suppression (LCIS) was not associated with a significant survival advantage and did not correlate with any known prognostic indicator. We conclude that phenotypic analysis of peripheral blood lymphocytes for CD38 antigen at diagnosis may be useful as a prognostic indicator in patients with myeloma. 相似文献
9.
Estimation of red cell flow microvessels: consequences of the Baker-Wayland spatial averaging model 总被引:1,自引:0,他引:1
The dual sensor cross-correlation method of H. Wayland and P.C. Johnson [1967), J. Appl. Physiol. 22, 333-337) has become a standard technique for determining the velocity of red blood cells (RBCs) in glass tubes and blood vessels. M. Baker and H. Wayland [1974), Microvasc. Res. 7, 131-143) found that under a variety of conditions the ratio of dual sensor velocity at the centerline of a glass tube to the blood velocity averaged over the lumen was close to 1.6. They provided an explanation of this factor based on spatial averaging of RBC velocity vertically through the tube as well as laterally across the face of the sensor. Their spatial averaging model could also account for the apparent blunting of RBC velocity profiles determined with the dual sensor technique. We used Baker and Wayland's spatial averaging model to calculate how the above velocity ratio depends on sensor size. A nonlinear relation between the velocity ratio and sensor size was found such that the velocity ratio varied from 1.6 to 1.33 as the ratio of sensor width to vessel or tube diameter was varied from 0 to 1. These results also hold for vessels or tubes of elliptic cross section. Some investigators have found that the velocity of red cells near the walls of blood vessels can be a substantial fraction of centerline velocity which suggests that RBC velocity distributions can be blunter than a Poiseuille distribution. We repeated the above calculation for blunted parabolic profiles and we found that the velocity ratio ranged from 1 for plug flow to 1.6 for Poiseuille flow. These calculations show that reliable estimates of RBC flow from dual sensor centerline velocity measurements require one to take into account the relative size of the sensor and blood vessel diameter as well as the bluntness of the RBC velocity distribution. 相似文献
10.
Eugene E Berg MD Doug DeHoll 《Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.]》1997,6(6):528
The anterior, posterior, and transverse bundles of the medial collateral ligaments of fresh cadaveric elbows were painted with a special radiopaque tantalum cyanoacrylic preparation. The extent of each ligament and their origins and insertions were examined with radiography. This study provided radiographic correlation for these important soft tissue structures and an anatomic understanding of elbow fractures with ligament avulsion. 相似文献