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Incorporation of radioactive precursors into macromolecules was studied with human normal and osteoarthritic articular cartilage organ culture. Analysis of the salt extracted matrix components separated by cesium chloride buoyant density gradient centrifugation showed an increase in the specific activities of all gradient fractions prepared from the osteoarthritic cartilage. Further analysis of these fractions showed the osteoarthritic cartilage contained 5 times as much sulfate incorporated into proteoglycans, and an even greater amount of 3H-glucosamine incorporated into material sedimenting to the middle of the gradient. Greater than half of this radioactive middle fraction appears to be hyaluronate, as judged by the position it elutes from a DEAE column and its susceptibility to hyaluronidase digestion. This study supports earlier findings showing increased rates of macromolecular synthesis in osteoarthritis, and in addition, an even greater synthetic rate for hyaluronic acid is demonstrated.  相似文献   
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This retrospective study reviews the medical records of 77 fetuses and babies with congenital diaphragmatic hernia (CDH) referred to two hospitals in Detroit from 1986 through 2000. The aims were to examine the effects on outcome of multiple variables, especially the type of CDH, associated anomalies, and ultrasound prognostic parameters. Ultrasound measurements of head (HC), chest (CC), and abdominal circumferences (AC) were obtained from videotapes. ANOVA and chi-square analysis were used to determine statistical significance between groups and proportions. Eighty-nine percent (65/73) of pregnancies resulted in live births, and 54% (35/65) of patients survived past 30 days. Liveborn patients with low APGAR scores were less likely to survive. Forty-three percent (30/70) had major associated anomalies, with cardiac anomalies constituting about 52% (33/64) of the major associated anomalies. Seventy percent of patients with isolated CDH survived versus 36% of patients with both CDH and cardiac anomalies. Sixty-seven percent (8/12) of fetuses antenatally diagnosed before 25 weeks of gestation survived past 30 days of birth. The survival rate of right-sided CDH with liver herniation was 80% (8/10), compared with 29% (4/14) for left-sided CDH with liver herniation (p=0.088). There was a significant linear relationship (r=0.603, p =0.029) between CC/AC and CC/HC among patients with CDH; survivors had higher CC/AC and CC/HC values than nonsurvivors. These results support the utility of CC/AC and CC/HC measurements and the presence of liver herniation as important prognostic factors that can be used in antenatal counseling and in planning clinical trials.  相似文献   
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作者于2004年在指导学生对一具90岁男性尸体标本进行解剖时,见其左前臂桡侧腕伸肌区存在有桡侧腕伸副肌(extensor carpi radialis accessorius,ECRA)合并桡侧腕长、短伸肌之间出现两条副肌腱并相互交叉连接的一种罕见的复合变异。  相似文献   
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Reacting to a pandemic influenza outbreak will require the mass distribution of vaccine, when available, which will require county health departments to set up and operate one or more mass vaccination clinics, also known as points of dispensing (PODs). Carefully planning these PODs before an event occurs is a difficult but important job. First, this article describes a tool--the Clinic Planning Model Generator computer program--designed to help public health agencies evaluate and make adjustments to their POD plans. The Clinic Planning Model Generator was built on data from a smallpox exercise and other biological agent POD exercises. Second, this article demonstrates the application of the Clinic Planning Model Generator through an example pandemic influenza scenario. This work is the result of an ongoing collaboration between Montgomery County, Maryland's Advanced Practice Center for Public Health Emergency Preparedness and Response, and the Institute for Systems Research at the University of Maryland.  相似文献   
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OBJECTIVE: To test the agreement between observers and reproducibility of a technique to display standard cardiac views of the left and right ventricular outflow tracts from four-dimensional volume datasets acquired with Spatiotemporal Image Correlation (STIC). METHODS: A technique was developed to obtain dynamic multiplanar images of the left ventricular outflow tract (LVOT) and right ventricular outflow tract (RVOT) from volume datasets acquired with STIC. Volume datasets were acquired from fetuses with normal cardiac anatomy. Twenty volume datasets of satisfactory quality were pre-selected by one investigator. The data was randomly assigned for a blinded review by two independent observers with previous experience in fetal echocardiography. Only one volume dataset was used for each fetus. After a training session, the observers obtained standardized cardiac views of the LVOT and RVOT, which were scored on a scale of 1 to 5, based on diagnostic value and image quality (1=unacceptable, 2=marginal, 3=acceptable, 4=good, and 5=excellent). Median scores and interquartile range, as well as inter- and intraobserver agreement were calculated for each view. RESULTS: The mean menstrual age at the time of volume acquisition was 25.5+/-4.5 weeks. Median scores (interquartile range) for LVOT images, obtained by the first and second observers, were 3.5 (2.25-5.00) and 4 (3.00-5.00), respectively. The median scores (interquartile range) for RVOT images obtained by the first and second observers were 3 (3.00-5.00) and 3 (2.00-4.00), respectively. The interobserver intraclass correlation coefficient for the LVOT was 0.693 (95% CI 0.380-0.822), and 0.696 (95% CI 0.382-0.866) for the RVOT. For the intraobserver agreement analysis, observer 1 gave higher scores to the LVOT the second time the volumes were analyzed [LVOT: 3.50 (2.25-5.00) vs. 5.00 (4.00-5.00, p=0.008)]. CONCLUSION: STIC can be reproducibly used to evaluate fetal cardiac outflow tracts by independent examiners. Slightly better image quality rating scores during the intraobserver variability trial suggests the presence of a learning curve for the manipulation and analysis of volume data obtained by STIC.  相似文献   
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