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121.
Evaluation of oxygen saturation monitoring by pulse oximetry in neonates in the delivery system 总被引:1,自引:0,他引:1
Ivan Dimich Prithi Pal Singh Alvin Adell Michele Hendler Norman Sonnenklar Mennakshi Jhaveri 《Journal canadien d'anesthésie》1991,38(8):985-988
The pulse oximeter was evaluated for use in neonates in the delivery room. One hundred neonates, delivered vaginally or by Caesarean section with general or epidural anaesthesia, were studied. After delivery, pulse oximetry probes were placed simultaneously on the ulnar side of the right hand and on the right Achilles tendon to determine whether there was a difference in arterial oxygenation (SpO2). Measurements of SpO2 were taken at 1, 5, 10 min, and 24 hr after delivery. At one and five minutes, SpO2 recorded from the right hand was higher than that recorded from the lower extremities (71.9% +/- 6.5% vs 63.4% +/- 4.3% and 83.3% +/- 4.2% vs 76% +/- 4.1%, mean +/- SD, respectively). At ten minutes these differences diminished, and had almost completely disappeared after 24 hr. These results can be explained by the presence of R-L shunting at the ductus arteriosus level, producing reduced SaO2 in the lower extremities. Oxygen saturation did not differ between neonates delivered vaginally or by Caesarean section, regardless of the presence or type of anaesthesia. We concluded that neonates remain relatively desaturated in the immediate postpartum period and that the SpO2 obtained from the right hand is a better index of neonatal oxygenation than that obtained from the heel. 相似文献
122.
Identification of intracellular receptor proteins for activated protein kinase C. 总被引:30,自引:5,他引:25 下载免费PDF全文
D Mochly-Rosen H Khaner J Lopez 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(9):3997-4000
Protein kinase C (PKC) translocates from the cytosol to the particulate fraction on activation. This activation-induced translocation of PKC is thought to reflect PKC binding to the membrane lipids. However, immunological and biochemical data suggest that PKC may bind to proteins in the cytoskeletal elements in the particulate fraction and in the nuclei. Here we describe evidence for the presence of intracellular receptor proteins that bind activated PKC. Several proteins from the detergent-insoluble material of the particulate fraction bound PKC in the presence of phosphatidylserine and calcium; binding was further increased with the addition of diacylglycerol. Binding of PKC to two of these proteins was concentration-dependent, saturable, and specific, suggesting that these binding proteins are receptors for activated C-kinase, termed here "RACKs." PKC binds to RACKs via a site on PKC distinct from the substrate binding site. We suggest that binding to RACKs may play a role in activation-induced translocation of PKC. 相似文献
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125.
The frequency of the hand trauma involving tissue losses generated the research for developing new technical solutions more simple and economic. The regional flaps, such as the distal pedicle Chinese flap, are usually surgeon's first choice whenever the local resources are over passed. Still, this type of Chinese flap would claim a major disadvantage as they involve the sacrifice of a vascular axis of the hand, sometimes even the dominant one. The operating team, would be able to avoid this inconvenience when using distal perforators based-on antibrachial radial flap; moreover, this technique would allow the covering of the substance losses, as far as the metacarpophalangeal joints. The authors report a clinical case. 相似文献
126.
A position paper on the subject of certified surgical specialists was published in 1966 under the direction of Professor
Charles Wells of Liverpool, England. President John Terblanche of the International Federation of Surgical Colleges brought
together leaders in surgical education from four nations (Australia, Japan, South Africa, United States) to update current
“state-of-the art” views. Presentations were made at the 38th Congress of the International Society of Surgery, August 18,
1999 in Vienna, Austria. After careful review of the four presentations, it was clear that surgeons all over the world have
made great improvements in the many facets of surgical education. Yet the advances remain spotty, with gaps noted when viewed
from an international perspective. 相似文献
127.
R Garcia-Carbonero J G Supko J Manola M V Seiden D Harmon D P Ryan M T Quigley P Merriam J Canniff G Goss U Matulonis R G Maki T Lopez T A Puchalski M A Sancho J Gomez C Guzman J Jimeno G D Demetri 《Journal of clinical oncology》2004,22(8):1480-1490
PURPOSE: To assess the efficacy of the marine-derived alkaloid ecteinascidin 743 (ET-743) in patients with soft tissue sarcomas that progressed despite prior conventional chemotherapy and to characterize the pharmacokinetic profiles of ET-743 in this patient population. PATIENTS AND METHODS: Thirty-six previously treated soft tissue sarcoma patients from three institutions received ET-743 as a 24-hour continuous intravenous (IV) infusion at a dose of 1,500 microg/m(2) every 3 weeks. Pharmacokinetic studies were also performed. Patients were restaged every two cycles for response by objective criteria. RESULTS: Objective responses were observed in three patients, with one complete response and two partial responses, for an overall response rate of 8% (95% CI, 2% to 23%). Responses were durable for up to 20 months. Two minor responses (43% and 47% tumor reduction) were observed, for an overall clinical benefit rate of 14%. The predominant toxicities were neutropenia and self-limited transaminitis of grade 3 to 4 severity in 34% and 26% of patients, respectively. The estimated 1-year time to progression and overall survival rates were 9% (95% CI, 3% to 27%) and 53% (95% CI, 39% to 73%), respectively. The maximum observed plasma concentration and total plasma clearance of ET-743 (mean +/- standard deviation), 1.04 +/- 0.48 ng/mL and 35.6 +/- 16.2 L/h/m(2), respectively, were consistent with previously reported values from phase I studies of the drug given as a 24-hour IV infusion. CONCLUSION: ET-743 is a promising new option for the management of several histologic subtypes of sarcoma. Durable objective responses were obtained in a subset of sarcoma patients with disease progression despite prior chemotherapy. Additionally, the relatively high survival rate noted in this series of previously treated patients further justifies development of this agent. 相似文献
128.
Richard J Wong Mei-Ki Chan Zhenkun Yu Ronald A Ghossein Ivan Ngai Prasad S Adusumilli Brendon M Stiles Jatin P Shah Bhuvanesh Singh Yuman Fong 《Clinical cancer research》2004,10(13):4509-4516
PURPOSE: Oncolytic herpes simplex viruses (HSVs) may have significant antitumor effects resulting from the direct lysis of cancer cells. HSVs may also be used to express inserted transgenes to exploit additional therapeutic strategies. The ability of an interleukin (IL)-12-expressing HSV to treat squamous cell carcinoma (SCC) by inhibition of tumor angiogenesis is investigated in this study. EXPERIMENTAL DESIGN: A replication-competent, attenuated, oncolytic HSV carrying the murine IL-12 gene (NV1042), its non-cytokine-carrying analog (NV1023), or saline was used to treat established murine SCC flank tumors by intratumoral injection. The expression of secondary antiangiogenic mediators was measured. Angiogenesis inhibition was assessed by in vivo Matrigel plug assays, flank tumor subdermal vascularity, and in vitro endothelial cell tubule formation assay. RESULTS: Intratumoral injections of NV1042 (2 x 10(7) plaque-forming units) into murine SCC VII flank tumors resulted in smaller tumor volumes as compared with NV1023 or saline. IL-12 and IFN-gamma expression in tumors was 440 and 2.2 pg/mg, respectively, at 24 h after NV1042 injection, but both IL-12 and IFN-gamma were undetectable (<0.2 pg/mg) after NV1023 or saline injections. Expression of two antiangiogenesis mediators, monokine induced by IFN-gamma and IFN-inducible protein 10, was elevated after NV1042 treatment. Matrigel plug assays of NV1042-transfected SCC VII tumor cells demonstrated significantly decreased hemoglobin content and microvessel density as compared with NV1023 and PBS. Excised murine flank tumors treated with NV1042 had decreased subdermal vascularity as compared with NV1023 and PBS. Both splenocytes and IL-12 expression by NV1042 were required for in vitro inhibition of endothelial tubule formation. CONCLUSIONS: IL-12 expression by an oncolytic herpes virus enhances therapy of SCC through antiangiogenic mechanisms. Strategies combining HSV oncolysis with angiogenesis inhibition merit further investigation for potential clinical application. 相似文献
129.
Duff EM Simpson SH Whittle S Bailey EY Lopez SA Wilks R 《The West Indian medical journal》2000,49(4):307-311
The aim of this study is to evaluate the impact of a six-month structured education programme on blood pressure (BP) control in patients with uncontrolled hypertension. All patients attending the Specialist Hypertension Clinic, University Hospital of the West Indies (UHWI), between January 4 and March 29, 1999, with blood pressure > 140/90 mmHg (n = 80), were randomly divided into Group 1, cases (n = 42) and Group 2, controls (n = 38). A 40-item pretested questionnaire, administered at the baseline and final visits of both groups, elicited demographic, lifestyle and knowledge data. Group 1 attended monthly structured interventions for six months. Except for diastolic blood pressure among male controls, diastolic blood pressure and systolic blood pressure were significantly reduced at the end of the intervention period (p < 0.01). Knowledge improved among the male patients (p < 0.01). Among the female patients, activity scores were significantly increased (p < 0.01), weight (p < 0.05) and BMI (p < 0.05) were significantly reduced. There were no differences in these variables among the controls. This intervention had a benefit in blood pressure control. 相似文献
130.
In recent years, the Spanish government has been battling to keep pharmaceutical expenditures under control. Its measures include control of prices, introduction of a "negative list" of drugs no longer reimbursed, increased cost-sharing, and introduction of overall budgets for pharmaceutical expenditures. Although the average prices of old pharmaceutical products declined by 39 percent over the last 15 years and consumption in value increased by only 10 percent, real pharmaceutical expenditures in Spain increased by 264 percent over that period. The main reason for the continuing rise in these expenditures and the failure of cost-containment measures is the introduction of new, more expensive drugs, which often fail to offer any real therapeutic advantages over products already on the market. This situation is exacerbated by a lack of effective demand-side measures such as budgets for doctors and lack of a generics market. 相似文献