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11.
In the absence of strong buffer catalysts, the degradation of codeine sulfate (7,8-didehydro-4,5 alpha-epoxy-3-methoxy-17-methylmorphinan-6 alpha-ol sulfate) in aqueous solution is described by the expression kobs = kH+ [H+] + k0 + kHO-[HO-], where kH+ = (3.9 +/- 1.3) X 10(-8) M-1 X S-1, k0 = (2.7 +/- 0.5) X 10(-8) S-1, and kHO- = (5.1 +/- 1.0) X 10(-6) M-1 X S-1 at 80 degrees C. The activation energies associated with these rate constants are 27.7, 21.0, and 28.3 kcal X mol-1, respectively. In the absence of buffer catalysis, codeine sulfate is predicted to have a room temperature shelf life of approximately 44 years between pH 1 and 10, significantly longer than the 1.1 year shelf life of codeine phosphate reported earlier.  相似文献   
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This study focuses on the injury rates for natural grass and AstroTurf surfaces and the risk factors of game position and type of play. We examined the game-related knee sprains, medial collateral ligament sprains, and anterior cruciate ligament sprains that occurred in the National Football League during the 1980 to 1989 seasons. The findings are controlled for categories of severity (number of games missed due to injury), position, and situation (rushing or passing) at the time of injury. The analysis of the data incorporates epidemiologic techniques associated with incidence density ratios. The data show that there is a statistically significant difference between the higher AstroTurf injury rates for knee sprains. When knee sprains are separated into medial collateral ligament sprains and anterior cruciate ligament sprains, only the anterior cruciate ligament sprains show a statistically significant higher injury rate for AstroTurf. When simultaneous control variables are considered, significantly more knee sprains occurred to backs on rushing plays and linemen on passing plays. When controlling the data for severity, only the Category II injuries (three or more games missed) sustained by linemen on passing plays had statistically significant higher injury rates for the AstroTurf. For medial collateral ligament sprains, only the Category II injuries for linemen on passing plays remain statistically significant. The data for the ACL sprains show statistically significant differences between the injury rate on natural grass and the injury rate on Astro Turf under conditions of special teams play.  相似文献   
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A prospective study was conducted to determine the frequency and distribution of bacterial and viral pathogens in infants hospitalized with suspected sepsis and to evaluate the potential of virus detection for improving patient management. A causative organism was detected in 157 (67%) of 233 previously healthy infants less than 3 months of age, who had been hospitalized for suspected sepsis: 19 (8%) had bacterial infections, 135 (58%) had viral infections, and 3 (1%) had mixed viral-bacterial infections. Viral infections occurred in a seasonal pattern: enteroviruses were responsible for most of the hospitalizations during summer and fall (65/110; 63%) and respiratory syncytial and influenza A viruses were responsible for most of the infections during winter (44/81; 55%). In contrast, bacterial infections were not seasonally distributed. Virus was detected in 33% of the 138 infected infants within 24 hours, and in 64% within 3 days. We conclude that viral infections are prevalent among infants hospitalized for suspected sepsis, and most can be detected early enough to influence patient management.  相似文献   
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ABSTRACT: Programs for preventing violence among youth should be evaluated to determine if they are effective. Nurses' logs appear to be a useful tool for evaluating school-based violence prevention programs. The logs provide a record of students' visits to the school nurse that can be used to determine if a violence prevention program is associated with a reduction in fighting—and other injury-related nurse visits. This method has many strengths: it is simple and inexpensive, it does not interrupt the school routine, it permits school-level rather than student-level data collection, it provides a ready "baseline," and it allows continuous data collection. However, potential limitations do exist. For example, the method may provide insufficient information and may be affected by factors unrelated to the intervention. School officials can increase the usefulness of the logs by encouraging standardization and providing training in their use.  相似文献   
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Gemtuzumab ozogamicin (GO) is a novel, targeted chemotherapy designed to treat acute myeloid leukemia (AML). GO consists of an antitumor antibiotic, calicheamicin, linked to a humanized monoclonal antibody against CD33. It has been approved in the United States since 2000 to treat CD33+ AML in first relapse in older adults who are not candidates for cytotoxic therapy. Beyond this indication, the role of GO is evolving. Single-agent GO has a limited role in de novo AML. Incorporation of GO into standard induction treatment in de novo and relapsed AML is feasible. Comparative phase III studies of such an approach are ongoing. GO is associated with serious toxicities, such as infusional reactions, transient liver function test abnormalities, and veno-occlusive disease of the liver, especially in patients who undergo hematopoietic stem cell transplantation.  相似文献   
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Huntington's disease (HD) is a neurodegenerative disorder associated with expansion of CAG trinucleotide repeats in the huntingtin gene. A minimum of 36 CAG repeats is usually reported in patients with clinical features of HD; 30 to 35 repeats represent an intermediate range. Here we report a 65-year-old male with autopsy-proven HD and 29 CAG repeats.  相似文献   
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