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41.
Jiao  Boshen  Hankins  Jane S.  Devine  Beth  Barton  Martha  Bender  M.  Basu  Anirban 《Quality of life research》2022,31(9):2729-2738
Quality of Life Research - There is a paucity of empirically estimated health state utility (HSU) values to estimate health-related quality of life among individuals with sickle cell disease (SCD)....  相似文献   
42.
Platelet activation and thrombus formation have been implicated to be detrimental for intraportal pancreatic islet transplants. The platelet-specific collagen receptor glycoprotein VI (GPVI) plays a key role in thrombosis through cellular activation and the subsequent release of secondary mediators. In aggregometry and in a microfluidic dynamic assay system modeling flow in the portal vein, pancreatic islets promoted platelet aggregation and triggered thrombus formation, respectively. While platelet GPVI deficiency did not affect the initiation of these events, it was found to destabilize platelet aggregates and thrombi in this process. Interestingly, while no major difference was detected in early thrombus formation after intraportal islet transplantation, genetic GPVI deficiency or acute anti-GPVI treatment led to an inferior graft survival and function in both syngeneic mouse islet transplantation and xenogeneic human islet transplantation models. These results demonstrate that platelet GPVI signaling is indispensable in stable thrombus formation induced by pancreatic islets. GPVI deficiency resulted in thrombus destabilization and inferior islet engraftment indicating that thrombus formation is necessary for a successful intraportal islet transplantation in which platelets are active modulators.  相似文献   
43.
Peripheral blood monocytes undergo an oxidative burst similar to that seen in neutrophils. The basis for this response appears to be an NAD(P)H oxidase that utilizes reduced NAD(P)H to form superoxide anion. We utilized the unique UV-stimulated fluorescence property of reduced pyridine nucleotides to analyze NAD(P)H utilization in monocytes. UV-stimulated fluorescence in mononuclear cell preparations indicated two populations of cells with the highly fluorescent cells having a Coulter volume consistent with that of monocytes. Dual laser analysis with monoclonal antibodies confirmed that these highly fluorescent cells are monocytes by showing them to be OKM1+, Leu DR+, and anti-monocyte 0.2+. Natural killer (NK) cells, as defined by Leu 7, were not found in this highly fluorescent population. Stimulation of mononuclear cells with phorbol myristate acetate caused a fluorescence loss indicative of NAD(P)H oxidation in monocytes but not in lymphocytes. Stimulation with suboptimal concentrations of PMA (1-5 ng/ml) resulted in a dose-dependent fluorescence loss in monocytes that occurred in an all-or-none fashion identical to the pattern observed in neutrophils. Simultaneous measurement of H2O2 production using dichlorofluorescein formation with NAD(P)H fluorescence indicates that oxidant production occurs in a graded manner. This method, then, provides a convenient way to study in single cells the metabolic events involved in depletion and replenishment of NAD(P)H during the oxidative burst and demonstrates an additional means by which to distinguish monocytes from lymphocytes using flow cytometry.  相似文献   
44.
Management of rectal injuries. Dogma versus practice   总被引:2,自引:0,他引:2  
The current treatment of civilian rectal injuries stems from military practice. Five principles have evolved: 1) complete fecal diversion, 2) debridement and closure, 3) rectal stump irrigation, 4) presacral drainage, and 5) broad spectrum antibiotics. To assess our practice results, the records of 52 consecutive patients with rectal injury seen at Detroit Receiving Hospital from 1980-88 were reviewed. Etiologies were gunshot (40), shotgun (9), anal assault (2), and stab (1). There were no blunt injuries and no deaths. Treatment consisted of celiotomy (52), diverting colostomy (51), presacral drains (35), rectal stump irrigation (26), and primary closure (1). Broad spectrum antibiotics were administered in all patients. Despite lack of universal application of the "standard" principles, only five patients had postoperative complications and none were related to the rectal injury. Our results demonstrate that a single approach may not be justified, as excellent outcome was achieved with low morbidity and no mortality despite selective management. The universal application of colostomy, repair, irrigation, drainage, and antibiotics cannot be supported.  相似文献   
45.
This prospective, double blind study was undertaken to test the efficacy of intravenous "minipulse" (100 mg) methylprednisolone (MP) therapy versus standard pulse (1000 mg) MP therapy in rheumatoid arthritis (RA). Thirty-six patients with RA synovitis flares were randomized to receive either 100 or 1000 mg MP IV QD x 3 doses. These 2 universally comparable groups exhibited no statistically significant differences in their striking prompt and sustained clinical improvement. These data suggest that minipulse MP is as efficacious as conventional pulse MP in the treatment of RA flares.  相似文献   
46.
A double-blind, crossover trial was conducted to examine the effect of albuterol aerosol on the fine-motor performance of children with chronic asthma. Twenty subjects, 4 1/2 to 14 1/2 years of age, were each tested after both the administration of albuterol aerosol and a placebo. The fine-motor composite of the Bruininks-Oseretsky Test of Motor Proficiency was used to evaluate abilities in response speed, visual-motor control, and speed and dexterity. The degree of tremor was tested with a "steadiness" tester, and postural adjustment was recorded on a clinical rating scale. No significant differences were found in fine-motor skills after albuterol or placebo administration, but a significant increase in tremor as well as in postural adjustment occurred after albuterol. The effect of test order and several other patient characteristics on test scores may be related to these findings. Major educational adjustments to compensate for the increase in tremor are unnecessary.  相似文献   
47.
Coupling of anthracyclines to high-molecular-weight carriers may alter drug disposition and improve antitumor effects. We have performed a clinical phase I trial of doxorubicin coupled to dextran (70000 m.w.). The drug was administered as single dose i.v. every 21–28 days. Thirteen patients have received a total of 24 courses (median 2; range 1–3). At the starting dose of 40 mg/m2 doxorubicin equivalent (DOXeq), WHO grade IV thrombocytopenia was noted in 2/2 patients. WHO grade IV hepatotoxicity and WHO grade III cardiotoxicity were noted in a patient with preexisting heart disease. Five patients were treated with 12.5 mg/m2 DOXeq. Maximal toxicity at this dose level was WHO grade III thrombocytopenia and local phlebitis (WHO grade II) in 1/5 patients, elevation of alkaline phosphatase (WHO grade III) and WHO grade III vomiting in another patient. Subsequently, five patients received 20 mg/m2 DOXeq. Hepatotoxicity was noted in 5/5 patients (1 × WHO grade IV, 1 × WHO grade III). Thrombocytopenia was noted in 3/5 patients (1 × WHO grade IV, 2 × WHO grade III). At 12.5 mg/m2 DOXeq, a patient diagnosed with a malignant fibrous histiocytoma had stable disease for 4 months. Pharmacokinetic analyses of total and free doxorubicin were performed in plasma and urine. The maximum peak plasma concentration (ppc) for total DOX was 12.3 g/ml at 40 mg/m2 DOXeq. The area under the plasma concentration time curve (AUC) ranged from 28.83–80.21 g/ml*h with dose-dependent elimination half lives (t1/2: 0.02–0.87 h;1/2: 2.69–11.58 h;1/2: 41.44–136.58 h). We conclude that the maximal tolerated dose (MTD) of AD-70 using this schedule is 40 mg/m2 DOXeq. The recommended dose for clinical phase II studies is 12.5 mg/m2 DOXeq.Abbreviations ALT Alanine Aminotransferase - AST Aspartate Aminotransferase - DOX Doxorubicin - DOXeq Doxorubicin Equivalent - ECG Electrocardiogram - HPLC High Pressure Liquid Chromatography - LD10 Lethal Dose for 10% of individuals - MTD Maximal Tolerated Dose - ppc Peak Plasma Concentration - WHO World Health Organisation  相似文献   
48.
BACKGROUND: Renal disease is commonly associated with hyperlipidemia and correlates with glomerular accumulation of atherogenic lipoproteins, for example, lipoprotein(a) [Lp(a)], and mesangial hypercellularity. Specific binding of Lp(a) to mesangial cells and induction of c-myc and c-fos expression has been demonstrated. Therefore, in this study, we investigated a possible growth stimulatory effect and mode of action of Lp(a) in human mesangial cells. METHODS: Lp(a) was purified from the regenerate fluid of a dextran sulfate column-based low-density lipoprotein apheresis system. Human mesangial cells were isolated by a sequential sieving technique from patients undergoing tumor nephrectomy. DNA synthesis was measured by [3H]-thymidine incorporation. The intracellular calcium concentration ([Ca2+]i) was determined by Fura 2-fluorescence, and inositol 1,4,5-trisphosphate (1,4,5-IP3) concentration was measured by a radioreceptor assay. RESULTS: The data show that Lp(a) bound to the cells with a Kd of 17.0 micrograms/ml and increased DNA synthesis and cell proliferation. Lp(a) caused a rapid increase in 1,4,5-IP3 and [Ca2+]i via a pertussis toxin-sensitive mechanism. The phospholipase C (PLC) inhibitor U73122 abolished Lp(a)-induced cell proliferation. In contrast, vasopressin-induced increase in 1,4,5-IP3 and [Ca2+]i was pertussis toxin insensitive. CONCLUSION: This study revealed that Lp(a) stimulates growth of human mesangial cells. Lp(a)-induced signaling involves binding to a receptor and stimulation of PLC via Gi proteins. Stimulation of PLC appears to be essential for the growth stimulatory effect of Lp(a). Whether these effects of Lp(a) contribute to the pathophysiology of renal disease needs to be determined.  相似文献   
49.
OBJECTIVES: To evaluate the accuracy of fluorodeoxyglucose positron emission tomography (PET) compared with computed tomography (CT) staging in patients with Stage I and II testicular germ cell tumors (GCTs). METHODS: From January 1995 to July 1997, in 37 patients with clinical Stage (CS) I (n = 25) and CS II (n = 12) GCT (24 nonseminomas, 13 seminomas), PET and CT were compared in the initial staging. After PET, the patients with nonseminomatous GCT were staged surgically by retroperitoneal lymph node dissection and the patients with seminomatous GCT were followed up clinically. RESULTS: Correct staging by PET was achieved in 34 of 37 patients compared with correct CT staging in 29 of 37 patients. Of 10 metastatic lesions, 7 and 4 were detected by PET and CT, respectively. PET did not show false-positive signals. PET was unable to detect vital cancer with a maximal diameter less than 0.5 cm or teratoma at any size. CONCLUSIONS: PET was useful for detecting viable tumor in lesions that are visible on CT scan and, thus, it may omit false-positive CS II lesions. However, PET was not able to identify mature teratoma. In this study, PET did not improve the staging in patients with CS I tumor.  相似文献   
50.
In response to the trend away from thinking of health care as a commodity to one in which quality is a differentiating feature among providers, primary care practices must focus on outcomes management. This article reviews the various clinical and office-based processes that influence practice outcomes. These include patient management, chart management, practice guidelines, clinical pathways, case management, and patient information. The key to a quality program and successful outcomes management is a commitment on the part of physicians to managing these processes so that best outcomes are achievable.  相似文献   
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