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1.
Birth weight on 12,644 singleton infants from 6,196 sibships born in Maryland between 1980 and 1984 were used to estimate the effects of nine maternal and infant covariates on the sibship correlation in birth weight. Assuming a homogeneous correlation across all families, the estimated intraclass correlation was 0.4664 (+/- 0.0099). This high sibship correlation makes it possible to predict, with reasonable accuracy, the birth weight of a child given information on previous sibs, as well as covariates on the mother and/or infant pertinent to a given pregnancy. The reduction in variance associated with incorporating information on the nine covariates used here was approximately equal to that obtained by conditioning on a single previous sib. Testing for heterogeneity in correlation among different groups of families showed that a crude measure of parity (first live birth vs. other), time between births, mother's marital status, and maternal age at the birth of the last child significantly influenced the sibship correlation in birth weight.  相似文献   
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Trotter's syndrome is a clinical triad of unilateral deafness, neuralgia affecting branches of the trigeminal nerve, and defective mobility of the soft palate, which is caused by malignant tumors involving the lateral pharyngeal recess (Rosenmüller's fossa). It is an ominous presentation, which can masquerade as dental or masticatory pain. Computerized tomography (CT) can be used not only to explain the anatomic basis of Trotter's syndrome but also to determine the extent and distribution of the malignant tumor involved. The advantages of CT over conventional radiography are illustrated by a case of adenoid cystic carcinoma that presented as Trotter's syndrome. Perineural invasion by tumor is shown on the gross level for the first time with CT, and important diagnostic considerations, which may aid in the early diagnosis of future cases, are discussed.  相似文献   
4.
Fate of micelles and quantum dots in cells.   总被引:2,自引:0,他引:2  
Micelles and quantum dots have been used as experimental drug delivery systems and imaging tools both in vitro and in vivo. Investigations of their fate at the subcellular level require different surface-core modifications. Among the most common modifications are those with fluorescent probes, dense-core metals or radionucleids. Cellular fate of several fluorescent probes incorporated into poly(caprolactone)-b-copolymer micelles (PCL-b-PEO) was followed by confocal microscopy, and colloidal gold incorporated in poly 4-vinyl pyridine-PEO micelles were developed to explore micelle fate by electron microscopy. More recently, we have examined quantum dots (QDs) as the next-generation-labels for cells and nanoparticulate drug carriers amenable both to confocal and electron microscopic analyses. Effects of QDs at the cellular and subcellular levels and their integrity were studied. Results from different studies suggest that size, charge and surface manipulations of QDs may play a role in their subcellular distribution. Examples of pharmacological agents incorporated into block copolymer micelles, administered or attached to QD surfaces show how the final biological outcome (e.g. cell death, proliferation or differentiation) depends on physical properties of these nanoparticles.  相似文献   
5.
The rising incidence of hepatocellular carcinoma (HCC) in western countries, along with the poor prognosis offered by present-day treatment modalities, makes novel therapies for this disease necessary. Oncolytic herpes simplex viruses (HSV) are replication-competent viruses that are highly effective in the treatment of a wide variety of experimental models of human malignancies. This study seeks to investigate the effectiveness of oncolytic herpes viruses in the treatment of primary HCC cell lines. Sixteen commercially available human HCC cell lines were studied. G207 is an attenuated, replication-competent, oncolytic HSV engineered to selectively replicate within cancer cells. Cell lines were tested for viral sensitivity to G207 and their ability to support viral replication using standard cytotoxicity and viral replication assays. Eleven of 16 cell lines were moderately to highly sensitive to G207 viral oncolysis. HCC cell lines additionally demonstrated the ability to support viral replication in vitro with as high as 800-fold amplification of the administered viral dose observed. G207 is cytotoxic to, and efficiently replicates within, HCC cell lines in vitro. From these data, we suggest that oncolytic HSV therapy may have a role in the treatment of HCC, and in vivo studies are warranted. Presented in part at the 2005 American Hepato-Pancreato-Biliary Association Congress, Hollywood, Florida, April 14–17, 2005. Supported by grants R01CA75461 and R01CA72632 from the National Institutes of Health, and by grant MBC-99366 from the American Cancer Society (Yuman Fong).  相似文献   
6.
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
7.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
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8.
We describe a case of acute left-sided visual loss in a 4-year-old boy. CT showed hyperdense retinal detachment with a tiny calcification, and MR imaging showed subretinal hyperintensity on both T1- and T2-weighted images. Proton MR spectroscopy showed a large peak between 1 and 1.6 ppm that we believe corresponds mainly to lipids, which are characteristic of the exudate present in Coats disease.  相似文献   
9.
Previous studies of sonograms in premenarchal girls have reported the typical ovary to be homogeneous in echogenicity, with cysts an uncommon finding, particularly in children less than 6 years old. These studies found no macrocysts (cysts greater than 9 mm in greatest length) in patients less than 11 years old. This information contradicts published pathology studies and our sonographic experience. The goal of this study was to determine the prevalence of cysts in the ovaries of premenarchal girls. The pelvic sonograms of 101 consecutive premenarchal girls between 2 and 12 years old, without known gynecologic or endocrinologic disease, were prospectively studied. One hundred fifty-five ovaries were adequately imaged in three dimensions. Ovaries were evaluated for the presence or absence of cysts (as defined by sonographic criteria), and the length of the cyst or of the largest cyst, if several were noted, was measured. Cysts were identified in 106 ovaries (68%). Cysts were seen in patients of all ages, particularly in the younger children (2-6 years old). Thirteen of the cysts, noted in 11 patients between 2 and 10 years old, were macrocysts. The typical sonographic appearance of the ovary in premenarchal girls is not homogeneous. Cysts are common in premenarchal girls between 2 and 12 years old and are the cause of the typical heterogeneous image. Macrocysts can be seen in healthy girls less than 11 years old.  相似文献   
10.
Oral lichen planus has been regarded as a condition with potential for malignant transformation. Critical evaluation of carcinoma cases arising in purported LP shows findings that raise several questions about the accuracy of initial LP diagnoses.  相似文献   
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