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31.
32.
M Clerici A Sarin R L Coffman T A Wynn S P Blatt C W Hendrix S F Wolf G M Shearer P A Henkart 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(25):11811-11815
In vitro T-cell receptor-induced programmed cell death in both activated T cells from human immunodeficiency virus-seronegative (HIV-) donors and resting T cells from HIV+ donors was substantially influenced by cytokines. Addition of exogenous recombinant "type 1" lymphokines interferon gamma and interleukin 2 (IL-2), as well as the macrophage-produced IL-12, which favor cell-mediated T-cell responses, blocks both systems of T-lymphocyte programmed cell death. In contrast, the "type 2" lymphokines IL-4 and IL-10, which favor antibody responses, either had no effect or enhanced these systems of in vitro T-cell programmed cell death. A role for endogenously produced cytokines was suggested by the inhibition of T-cell receptor-mediated death by antibodies against IL-4 and IL-10 and its enhancement by anti-IL-12 in cultures containing monocytes. These results demonstrate that the functional properties of type 1 and type 2 cytokine classes may be further extended to include their effects on T-cell programmed cell death and their possible role in the pathogenesis of HIV infection. 相似文献
33.
Dekkers PA Lawson DS Smigla GR Shearer IR 《The Journal of extra-corporeal technology》1995,27(3):152-157
The Terumo Capiox SX18R is a commercially available, low prime, reverse phase, hollow fiber membrane oxygenator. The oxygenator consists of a 1.8 m2 microporous polypropylene hollow fiber bundle, a 2200 cm2 tubular stainless steel heat exchanger, and an open hard shell venous reservoir with integral cardiotomy filter. The Terumo Capiox SX18R oxygenator was evaluated to determine its clinical oxygenating performance. Blood samples were drawn from 25 patients yielding 114 data points. The following parameters were recorded: blood flow, cardiac index, gas flow, gas to blood flow ratio, and oxygen fraction. Samples were assayed for hematocrit, hemoglobin, arterial and venous blood gas values, and venous oxygen saturation. The data and assay results were used to calculate arterial, venous, and membrane gas oxygen content, oxygen transfer, shunt fraction, and oxygen diffusion capacity. The Terumo Capiox SX18R oxygenator performed adequately with sufficient oxygen transfer reserve and carbon dioxide clearance under a variety of clinical conditions for the tested population. 相似文献
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35.
Zárate E Sá Rêgo MM White PF Duffy L Shearer VE Griffin JD Whitten CW 《Anesthesiology》1999,90(4):956-963
BACKGROUND: Because adenosine has been alleged to produce both anesthetic and analgesic sparing effects, a randomized, double-blinded study was designed to compare the perioperative effects of adenosine and remifentanil when administered as intravenous adjuvants during general anesthesia for major gynecologic procedures. METHODS: Thirty-two women were assigned randomly to one of two drug treatment groups. After premedication with 0.04 mg/kg intravenous midazolam, anesthesia was induced with 2 micro/kg intravenous fentanyl, 1.5 mg/kg intravenous propofol, and 0.6 mg/kg intravenous rocuronium, and maintained with desflurane, 2%, and nitrous oxide, 65%, in oxygen. Before skin incision, an infusion of either remifentanil (0.02 microg x kg(-1) x min(-1)) or adenosine (25 microg x kg(-1) x min(-1)) was started and subsequently titrated to maintain systolic blood pressure, heart rate, or both within 10-15% of the preincision values. RESULTS: Adenosine and remifentanil infusions were effective anesthetic adjuvants during lower abdominal surgery. Use of adenosine (mean +/- SEM, 166+/-17 microg x kg(-1) x min(-1)) was associated with a significantly greater decrease in systolic blood pressure and higher heart rate values compared with remifentanil (mean +/- SEM, 0.2+/-0.03 microg kg(-1) x min(-1)). Total postoperative opioid analgesic use was 45% and 27% lower in the adenosine group at 0-2 h and 2-24 h after surgery, respectively. CONCLUSIONS: Adjunctive use of a variable-rate infusion of adenosine during desflurane-nitrous oxide anesthesia was associated with acceptable hemodynamic stability during the intraoperative period. Compared with remifentanil, intraoperative use of adenosine was associated with a decreased requirement for opioid analgesics during the first 24 h after operation. 相似文献
36.
Lawson DS Darling EM Collins K Smigla GR Shearer IR 《The Journal of extra-corporeal technology》1999,31(2):91-96
A survey directed to centers offering both pediatric and adult perfusion services was conducted to determine how pediatric cases were distributed among individual perfusionists in their departments. These centers were also asked what they believed the clinical activity level should be for a perfusionist each year to remain proficient in pediatric cardiopulmonary bypass. The questions were asked via e-mail and then followed up with telephone interviews as necessary. Out of the 100 centers contacted, 45 responded to the survey (43 North American, 2 European). Of the forty-five centers, forty-one provided both pediatric and adult perfusion services. Thirty-two centers (78%) offering adult as well as pediatric perfusion services distributed the pediatric caseload to a select group of perfusionists. Nine centers (22%) distributed the pediatric open-heart caseload to the entire staff. From the respondents, the average minimum number of pediatric cases believed necessary to remain proficient in pediatric perfusion was 42.8 cases annually. Centers having dedicated pediatric perfusionists had a slightly higher annual caseload than did those at non-specialized centers, despite practicing at institutions averaging fewer pediatric open-heart cases annually. 相似文献
37.
Graham WP Shearer AW Mackay DR Santo J Stratis JP 《Annals of plastic surgery》1999,42(4):411-6; discussion 416-7
Wallace aptly described patients with overriding psychological problems and upper extremity complaints as possessing the Shaft syndrome. SHAFT patients studied fell into two categories. The first group inflicted physical harm on themselves, creating factitious injuries. The second group postured their limbs in attitudes that are not explainable anatomically. This latter group is described by Simmons as the clenched fist syndrome. Although patients who had factitious injuries invariably healed with protective casting, 4 patients relapsed. Eight of 14 patients who were employed at the onset of their complaints returned to gainful employment. Some patients received psychological counseling but most lacked sufficient insight to make gainful progress. Reaching a diagnoses was often difficult. At least 5 patients had unwarranted operations. The surgeon needs a high index of suspicion when the history and findings do not match for patients harboring complaints of pain, numbness, stiffness, or inability to use their limb. 相似文献
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39.
K.BM. LEE J.M. LEE† C.Y. PARK K.B. LEE H.Y. CHO‡ & S.Y. HA‡ 《International journal of gynecological cancer》2006,16(4):1569-1573
The objective of this study was to investigate the efficacy of treatment strategies in patients with adenocarcinoma (AC) of the cervix and compare it with those with squamous cell carcinoma (SCC) of the cervix. Women with FIGO (1994) stage IB1 AC, especially pathologic tumor size of 2-4 cm, treated with class III hysterectomy, were compared with those with SCC treated with comparable strategy in a case-controlled study. Eighty patients (20 cases, 60 controls) were analyzed. Lymphvascular space invasion (P = 0.01) and lymph node metastasis (P = 0.07) were more frequent in patients with SCC than in those with AC. However, there was no significant difference in depth of stromal invasion (P = 0.51) and invasion of the parametrium (P = 0.44) between two groups. And there was also no statistically significant difference in disease-free survival (P = 0.86) and overall survival (P = 0.89) between two groups. Primary radical surgery followed by adjuvant therapy, same as for SCC, would be acceptable for AC with pathologic tumor size of 2-4 cm. Although it was difficult to determine whether AC recurred more systemically, more effective treatment strategies than those currently available for AC should be considered to reduce the systemic recurrence. 相似文献
40.
Tear of the distal biceps brachii tendon is an uncommon injury. Ultrasound evaluation of the distal tendon using an anterior approach is often difficult because of technical factors. We describe a new method of ultrasound evaluation of the distal biceps tendon insertion. This involves a posterior approach with the forearm pronated. With pronation of the forearm, the radial tuberosity faces posteriorly, bringing the distal biceps tendon insertion into view. A surgically proven case of distal biceps tendon tear is presented to illustrate our technique. 相似文献