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31.
M F Matangi J A Strickland J J Burgess E F Busse 《The Canadian journal of cardiology》1987,3(7):342-344
Operative mortality, postoperative morbidity and follow up data were analyzed retrospectively from 122 consecutive patients, over 65 years old undergoing elective aortocoronary bypass grafting for symptomatic relief of angina pectoris at the Plains Health Centre, Regina, Saskatchewan, from January 1980 to December 1985. There were two in-hospital deaths (operative mortality 1.6%). Definite perioperative myocardial infarction occurred in 12 patients (9.8%). The 120 survivors were followed for a mean of 32 months. There were three deaths during follow-up, giving a five-year probability of survival of 93%. Twenty-three clinical events (including deaths) occurred during follow-up, giving a five-year probability of event free survival of 72%. Ninety percent of patients say they are pleased with their operation. Seventy-eight percent are currently angina free. These data illustrate the effectiveness of aortocoronary bypass grafting in low risk elderly patients with symptomatic coronary artery disease. 相似文献
32.
Richard A. Hill Terri Esterowitz Julie Ryan Lih-Huei L. Liaw J. Stuart Nelson Hideko Yashiro Tatiana Krasieva Michael W. Berns 《Lasers in surgery and medicine》1995,17(2):166-171
Background and Objective: To investigate Photofrin® (PII) and CASPc for photodynamic therapy (PDT) of the ciliary body in rabbits. Study Design/Materials and Methods: PII (10 mg/kg) or CASPc (1 mg/kg) was given by ear vein. Pharmacokinetics were studied in frozen sections by fluorescence microscopy (CCD camera based low light detection system with digital image processing) at 1 and 24 h (8 rabbits;16 eyes). Laser light was delivered (argon pumped dye laser;630 and 675 nm;8 rabbits;16 eyes) by contact fiberoptic. To compensate for iris attenuation, irradiance was 125 mW/cm2 (20, 40, 80, or 160 J/cm2). Controls (4 rabbits;8 eyes) received laser light without photochemicals (OD) and for comparison, continuous wave Nd:YAG laser by fiberoptic (0.8–1.2J;OS). Results: Localization studies showed intravascular distribution with some selective ciliary body distribution at 24 h (PII > CASPc). Rabbits treated with PII or CASPc exhibited variable amounts of gross ciliary body edema, infarction, and necrosis by 24–48 h. This response was not seen in PDT control tissues;damage was seen in the iris and ciliary body, with partial vacuolization of the pigment epithelium. Conclusion: PDT may offer a more selective approach to ciliary body destruction. A small but significant thermal effect was seen during PDT from melanin photon uptake with damage to iris and ciliary body. Thermal damage and potential interaction with ocular visual pigments may limit use of these photochemicals and wavelengths for PDT of the ciliary body © 1995 Wiley-Liss, Inc. 相似文献
33.
Neuronal death in the central nervous system demonstrates a non-fibrin substrate for plasmin
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Stella E. Tsirka Thomas H. Bugge Jay L. Degen Sidney Strickland 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(18):9779-9781
Mice deficient for plasminogen exhibit a variety of pathologies, all of which examined to date are reversed when the animals are also made fibrin(ogen) deficient. These results suggested that the predominant, and perhaps exclusive, physiological role of plasminogen is clearance of fibrin. Plasminogen-deficient mice also display resistance to excitotoxin-induced neurodegeneration, in contrast with wild-type mice, which are sensitive. Based on the genetic interaction between plasminogen and fibrinogen, we investigated whether resistance to neuronal cell death in the plasminogen-deficient mice is dependent on fibrin(ogen). Unexpectedly, mice lacking both plasminogen and fibrinogen are resistant to neurodegeneration to levels comparable to plasminogen-deficient mice. Therefore, plasmin acts on substrates other than fibrin during experimental neuronal degeneration, and may function similarly in other pathological settings in the central nervous system. 相似文献
34.
Clarithromycin is known to accumulate in polymorphonuclear leukocytes, but no accumulation studies with macrophages have been reported. We exposed J774 macrophages, grown for 4–6 days, to clarithromycin 3.0 μg/ml for 2 hours. The cells were separated from the extracellular fluid, and the concentration of clarithromycin was determined in an agar diffusion bioassay. The accumulation of clarithromycin was 15.8-fold greater in the cells than it was in the extracellular fluid when the test was performed with noninfected cells, and 17.3-fold greater for cells infected with Mycobacterium avium. However, the ratio was substantially lower, only 3.7 for dead macrophages, suggesting that intracellular accumulation is probably an active process. These data may clarify the nature of the activity of clarithromycin against M. avium in macrophages. 相似文献
35.
Background: Tibialis posterior is a frequent cause of an acquired flatfoot deformity and the prevalence is not known. If tibialis posterior dysfunction was found to occur frequently, a greater awareness may result leading to earlier patient diagnosis, referral and treatment.Objectives: To validate a screening questionnaire for tibialis posterior dysfunction, and to investigate the prevalence of tibialis posterior dysfunction in a high-risk patient population.Methods: The screening questionnaire was given prospectively to 65 patients (44 females, 21 males; mean age 79.6 years) attending an unrelated care of the elderly appointment. A foot and ankle surgery fellow separately examined all feet for tibialis posterior dysfunction.Results: The survey was 100% sensitive and 98.3 % specific at detecting tibialis posterior dysfunction. Six of the 65 patients (5 females, 1 male) had tibialis posterior dysfunction, and two had bilateral involvement. All six of the patients had longstanding symptoms, all had consulted their doctor and three had seen an orthopaedic surgeon; only one of the six patients had been correctly diagnosed.Conclusions: This study suggests that tibialis posterior dysfunction occurs frequently, but is seldom diagnosed in elderly women. Further epidemiologic studies are needed to determine the true prevalence. 相似文献
36.
Julie Hicks Patrick Jenessa C. Johnson R. Turner Goins David K. Brown 《Quality of life research》2004,13(5):959-967
This study investigates functional disability among some of the nation's most vulnerable older adults: rural Medicaid recipients. Data were provided by 221 older adults (mean age = 75.9 years; 82% women) who were receiving community-based long-term care services through Medicaid. Participants self-reported functional ability involving the completion of six basic activities of daily living (BADLs), three cognitive instrumental activities of daily living (IADLS), and four physical IADLs. Self-reports of depressed affect and the number of physical health conditions were also obtained. Path analysis was used to examine all of the associations among age, gender, number of chronic health conditions, depressed affect and functional disability. The tested model was significant [chi2 (DF = 3, n = 221) = 5.052, p = 0.168; TLI = 0.945; CFI = 0.992; RMSEA = 0.056] and explained 45.1% of the variance in BADL disability. Depressed affect significantly predicted disability in cognitive IADLs and physical IADLs, which predicted disability in BADLs. Age and gender had indirect effects on BADL, through their association with cognitive IADLs and physical IADLs. The number of chronic health conditions exerted both indirect and direct effects on BADL disability. Results are discussed within the context of the growing literature that suggests the importance of psychological variables as predictors of functional disability. Moreover, we discuss whether community-based long-term care is appropriate for older adults with high levels of functional disability. 相似文献
37.
The effects of glycine on the phasic changes in locomotor activity in the rat, caused by a persistent infusion of dopamine (DA) into the nucleus accumbens (ACB) were investigated. Dopamine (25 μg/24 hr), infused into the nucleus accumbens for 13 days, caused hyperactivity, with two peaks occurring on days 3–4 and 9–11. Glycine (12.5 or 25 μg/24 hr) infused into the nucleus accumbens on its own did not alter the locomotor activity, yet when infused at the same time as DA (25 μg/24 hr), glycine (12.5 or 25 μg/24 hr) inhibited the development of the first peak of hyperactivity induced by DA, with no effect on the second peak. A larger dose of glycine (50 μg/24 hr), infused alone, significantly increased locomotor activity, and a combination of this dose with DA (25 μg/24 hr), led to a temporal shift in the response to DA such that the first peak of hyperactivity was delayed to “fuse” with the second peak. The locomotor response to a threshold dose of DA (6.25 μg/24 hr) plus glycine (50 μg/24 hr) was no greater than could be accounted for by the hyperactivity response to glycine alone (50 μg/24 hr). Strychnine (10 μg/24 hr), infused into the nucleus accumbens, produced no alteration in locomotor activity. Similarly, when infused together with DA (25 μg/24 hr), strychnine (10 μg/24 hr) caused no significant alteration in the phasic hyperactivity induced by DA. However, strychnine (10 μg/24 hr), infused together with DA and glycine (25 and 12.5 μg/24 hr respectively), prevented the inhibition by glycine of the first peak of hyperactivity induced by DA. The results indicate that while glycine may not normally exert a tonic modulatory influence on those mechanisms in the nucleus accumbens which regulate locomotor activity, when applied exogenously glycine can partially moderate the locomotor response to DA, through an action on strychnine-sensitive receptors. 相似文献
38.
S C Gross H K Watson J W Strickland A K Palmer L H Brenner J Fatti 《The Journal of hand surgery》1989,14(1):95-102
Until recently the problem of painful, symptomatic arthritis of the wrist secondary to congenitally incomplete separation of carpal bones has been infrequently recognized. Five patients with either excessive stress loading or trauma had eight symptomatic wrists with congenitally incomplete separation of the triquetral-lunate joint. Three of these patients had bilateral symptoms. Six of the wrists had been treated by a limited wrist arthrodesis of the triquetral-lunate joint resulting in asymptomatic wrists and improved range of motion. It appears that patients with this congenital condition poorly tolerate stress loading or trauma secondary to deficient intra-articular cartilage formation resulting in a clinical and anatomic state similar to degenerative arthritis. We suggest a limited wrist arthrodesis as definitive treatment for symptomatic congenitally incomplete separation of the triquetral-lunate joint, with possible application in incomplete separation of the other intercarpal joints. 相似文献
39.
40.
Marcia C Willing James C Torner Trudy L Burns Kathleen F Janz Teresa A Marshall Julie Gilmore John J Warren Steven M Levy 《Journal of clinical densitometry》2005,8(1):39-47
Four hundred twenty-eight white children (200 boys and 228 girls) ages 4.5-6.5 yr had spine, hip, and whole-body bone mineral density (BMD) and bone mineral content (BMC) measured by dual-energy X-ray absorptiometry(DXA) as part of the Iowa Bone Development Study. Anthropometric measurements, including height, weight, and body mass index (BMI) were determined for each child at the time the bone measurements were made. The age- and gender-specific height percentile based on the 2000 CDC Growth Charts (www.cdc.gov/growthcharts/) was determined for each child. These percentiles were used to classify children into four groups as defined by the 25th, 50th,and 75th percentile cutpoints. Percentile distributions were determined within each height quartile group to delineate percentiles (5th, 25th, 50th, 75th, 95th) for BMD and BMC. Gender differences in BMD and BMC were investigated before and after stratification into height groups. Boys had higher age-height-weight-adjusted means for most BMD and BMC measures except spine BMD. Bone measurements increased with height quartile, indicating that taller children have greater BMD and BMC compared to shorter children of the same age and gender. Within any given quartile,mean BMD and BMC measurements were similar for boys and girls, with the exception of hip BMD, for which values were consistently higher for boys (p < 0.05). In addition, whole-body BMC values were higher for boys in quartiles 1 and 3 (p < 0.05). These bone measures provide norms for young white children and serve as a reference for comparison with other racial and ethnic groups, as well as with childhood populations that are at risk for osteopenia because of chronic disease. Gender, age, and height are useful clinical predictors of BMD and BMC in young children. 相似文献