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排序方式: 共有514条查询结果,搜索用时 15 毫秒
31.
de Jonge E Friederich PW Vlasuk GP Rote WE Vroom MB Levi M van der Poll T 《Clinical and diagnostic laboratory immunology》2003,10(3):495-497
The activation of coagulation has been shown to contribute to proinflammatory responses in animal and in vitro experiments. Here we report that the activation of coagulation in healthy human subjects by the administration of recombinant factor VIIa also elicits a small but significant increase in the concentrations of interleukin 6 (IL-6) and IL-8 in plasma. This increase was absent when the subjects were pretreated with recombinant nematode anticoagulant protein c2, the inhibitor of tissue factor-factor VIIa. 相似文献
32.
OBJECTIVE: Our objectives were to describe the characteristics of "mixed practices"-that is, practices performing both diagnostic radiology and radiation oncology services-and to compare mixed practices with multiradiologist diagnostic radiology-only practices. MATERIALS AND METHODS: In 1999, the American College of Radiology surveyed 970 practices by mail, using a 65-item questionnaire. A response rate of 66% was achieved. Responses were weighted such that they were representative of all the radiology practices in the United States. The estimates cited in this article were primarily drawn from this 1999 survey. RESULTS: Mixed practices were nearly evenly divided between large (area population, > or = 1 million) and small metropolitan areas (area population, from 50,000 to 1 million). We found that 63% of mixed practices were nonacademic private practices; 27% were academic. Approximately 50% contained 15 or more members. Mixed practices were predominantly owned by members of the practice and predominantly served both hospitals and nonhospital settings. At least 90% of mixed practices performed mammography, imaging-guided breast biopsy, sonography, and nuclear medicine.We found that compared with multiradiologist diagnostic radiology-only practices, mixed practices were larger and were more likely to be academic, to serve both hospital and nonhospital settings, and to perform interventional and nuclear medicine procedures. CONCLUSION: The characteristics of a mixed practice differ from those of a multiradiologist diagnostic radiology-only practice. 相似文献
33.
High-risk pregnancy is the most common clinical association with antiphospholipid antibodies; the principal manifestations are pregnancy loss and early preeclampsia. Membership in this family of antibodies is continually growing and includes antibodies against a variety of phospholipids, phospholipid-protein complexes, and phospholipid-binding proteins. The current information in the literature is inadequate to clearly implicate a subgroup of antiphospholipid antibodies or a particular pathophysiologic mechanism as being responsible for poor pregnancy outcomes. It is clear, however, that prevalent diagnostic tests for LA and aCL are extremely useful to identify many of these patients, but are inadequate for diagnosis of all patients with autoimmune pregnancy loss or to elucidate the pathophysiology. Many patients who present clinically with autoimmune-like pregnancy complications currently are negative in tests for LA or aCL, but have antibodies against annexin V, phosphatidylserine, or other relevant antigens. The greatest risk for a complicated pregnancy is conveyed by a subgroup of antibodies that affect the normal function of placental trophoblast. As clinical laboratory tests designed to detect more members of the antiphospholipid antibody family become available, understanding of this complicated disease (APS) will increase. 相似文献
34.
PURPOSE: To determine whether the initial angiographic morphology and location of intracranial arterial occlusions in acute stroke are reliable predictors of success of thrombolysis. MATERIALS AND METHODS: Thirty-three intracranial occlusions were studied in 32 patients who underwent intraarterial thrombolysis with urokinase within 6 hours from clinical onset of stroke symptoms. The initial angiographic appearance of each occlusion was categorized as cutoff, tapered, meniscus, tram-track, or tandem. Following thrombolysis, outcomes were classified as complete, partial, or no recanalization. RESULTS: Complete recanalization was accomplished in 17 of the 33 lesions, partial recanalization in nine, and no effect in seven. Tram-track (n = 3) and tapered (n = 7) lesions demonstrated the highest rates of at least partial recanalization (100% and 86%, respectively), whereas cutoff lesions (n = 13) demonstrated the lowest rate (69%). Intracranial hemorrhage was associated with higher doses of urokinase. Complete recanalization success rates were 60% for M1 lesions (n = 10), 43% for M2 or A2 lesions (n = 14), and 33% for M3 lesions (n = 3). Vertebrobasilar lesion (n = 5) success rates for complete and at least partial recanalization were 80% and 100%, respectively. CONCLUSION: Relationships were found to exist between the success rate of recanalization and initial angiographic lesion location and morphology, which represent important trends; however, further studies with a larger sample size are needed. 相似文献
35.
PURPOSE: To evaluate the current practice of and job market for pediatric radiologists in the United States and Canada with a 1998 survey and compare findings with those of surveys from 1980 and 1989. MATERIALS AND METHODS: Surveys were mailed to the 728 active members of the Society for Pediatric Radiology. Questions covered professional practice, subspecialization, and involvement in evolving technologies. A pediatric radiology help-wanted index was generated from a diagnostic radiology help-wanted index. RESULTS: Increasing involvement in the interpretation of computed tomographic, ultrasonographic, and magnetic resonance images was found among the 57% (411 of 728) of the members who responded. The attainment of a certificate of added qualification in pediatric radiology was found in nearly three-fourths of the membership, and 85% (348 of 408) had completed a fellowship. More than half of the respondents were involved in interventional procedures amid a continued increase in volume; 24% (100 of 409) of the membership, as compared with 7% in the 1980 survey, was practicing in a community or "other" setting. Subspecialization within pediatric radiology had diminished, and there was a larger percentage of female pediatric radiologists, particularly among the newest members. The job market was robust, having recovered substantially since the middle 1990s. CONCLUSION: The practice of pediatric radiology has evolved, with increasing involvement in advanced techniques and modalities, as well as a greater presence in community settings. The help-wanted index supports the recent discussions of a personnel shortfall. 相似文献
36.
Olson NZ Sunshine A Zighelboim I Lange R 《International journal of clinical pharmacology and therapeutics》1999,37(4):168-174
OBJECTIVE: The objective of this single-center, single-dose, double-blind randomized parallel group study was to evaluate the analgesic efficacy of a new liquid formulation of ketoprofen at two dose levels (25 mg or 50 mg) compared to a commercially available liquid form of dipyrone 500 mg and placebo with all treatments administered as drops to patients with severe postepisiotomy pain. METHODS: The study was designed with a sample size of 69 patients per treatment for a total of 276 patients. However, due to administrative changes at the site, the study was prematurely terminated; thus only 108 patients (26 to 28 patients per treatment), 18 years or older, with severe postepisiotomy pain were randomized to one of the four treatments. Treatments were assessed over a 6-hour period using standard scales for pain intensity and pain relief and a number of derived variables based on these data. Since the study medications were not identical in appearance, the preparation and administration of the study medication, and the observation of the patient, were carried out by two different individuals to maintain double-blind conditions. RESULTS: All active treatments were significantly superior to placebo for several measures of analgesia including 4-hour and 6-hour SPID and TOTPAR scores. The global rating was assessed as "good" or "excellent" by over 75% of the patients in the active treatment groups compared to 7.4% of the patients in the placebo group. Reduction in pain intensity was very similar for the two-dose levels of ketoprofen and the comparator dipyrone 500 mg. CONCLUSION: Ketoprofen 25 mg or 50 mg, and dipyrone 500 mg seem to be equally suited for use as pain relief medication after minor surgery, as well as episiotomy. This study did not demonstrate a need for more than 25 mg of ketoprofen in postepisiotomy pain. All treatments were well tolerated. No adverse events were reported. 相似文献
37.
D K Stevenson D S Kasting R A Darnall R L Ariagno J D Johnson N Malachowski C L Beets P Sunshine 《The Journal of pediatrics》1979,95(4):595-599
Thirty-nine critically ill infants with pulmonary disease received tolazoline because of severe hypoxemia refractory to administration of 100% O2 and mechanical ventilation. Twenty-seven (69%) of the infants responded with an increase in PaO2 greater than or equal to 20 torr in the first umbilical arterial gas after completion of the initial ten-minute infusion (1 to 2 mg/kg) of the drug. A response was not correlated with survival. The overall survival was 46%, essentially unchanged from our previous report (44%). Infants with hyaline membrane disease had the poorest survival rate (33%). Complications associated with the use of tolazoline occurred in 82% of the infants. A hypotensive reaction, defined as a 25% decrease in mean arterial pressure from the pre-tolazoline level, occurred in 67% of the infants, and more commonly in the infants with RDS (87%). In 11 infants who did not respond to the initial dose of tolazoline, the dose was increased up to 10 mg/kg/hour; only one infant responded, and eight (73%) had a hypotensive reaction. 相似文献
38.
M A Pass J D Johnson I A Schulman C F Grumet E B Hafleigh N C Malachowski P Sunshine 《The Journal of pediatrics》1976,89(4):646-651
A prospective study was carried out to identify the immediate and long-range advantages and disadvantages of a walking-donor transfusion program for an intensive care newborn nursery. The effect of heparin on coagulation of blood was evaluated and found to be minimal. There was no evidence of transmission of HBSAg. The prevalence of CMV infection at the time of follow-up was higher in infants who had received blood from donors seropositive for CMV than in infants who had been transfused from seronegative donors. In our experience, a walking-donor program has been a safe and effective method for the provision of small transfusions of blood to sick neonates. 相似文献
39.
Knowing the total number of radiologic services provided in the United States and their cost is important. This information can, for example, indicate the opportunities available to a radiology practice considering opening a new office or show whether high-technology radiology is, as is widely assumed, an important factor in United States health costs. However, neither the total number of procedures nor their cost is known. We developed two largely independent estimates of each total (one based principally on surveys of radiologists, the other on Medicare data) to cross-validate the estimates and provide an indication of their uncertainty. We estimate that 260-330 million radiologic procedures were performed in the United States in 1990 (including both diagnostic and therapeutic procedures and radiologic procedures performed by nonradiologists) and that payments for these services totaled $19 to $22 billion (including payments for technical components in the hospital setting). This total was approximately 3.5% of national spending on personal health care; high-technology radiology totaled less than half of this amount. The procedures numbered 1.0-1.3 per capita annually, an increase of some 10-40% since 1980. Of the spending total, $10 to $12 billion was paid to physician practices, with a substantial portion of this amount going ultimately to practice expenses, particularly in the office setting. Our results suggest that spending on high-technology radiology is too small to be a major explanation for the current level of health costs in the United States. 相似文献
40.
PURPOSE: To identify and explain variations and trends in the professional satisfaction of radiologists. MATERIALS AND METHODS: Questionnaires were mailed during the winter of 1994-1995 to a stratified random sample of 3,024 diagnostic radiologists, radiation oncologists, and nuclear medicine specialists; 75% responded. We weighted the responses to make them representative of all radiologists in the United States and compared the findings with those of similar previous surveys. RESULTS: Fifty-one percent of radiologists would recommend a career in radiology to a college-age adult, which is down from 65% in 1990 but up from 42% in 1998. Forty-one percent said they liked working in radiology less than they did 5 years ago, whereas 22% said they liked it more. Radiologists' perceptions of managed care's effect on their practice had more influence on professional satisfaction than did its administrative intrusions or the actual percentage of managed care patients in their practice. Other factors associated with decreased satisfaction were increased administrative duties and government involvement. CONCLUSION: Satisfaction in the radiology profession declined during a period of dramatic change and uncertainty. Fear about managed care rather than its actual effect was the dominant factor in the decrease. Therefore, it is unsound to predict a long-term decline in professional satisfaction. 相似文献