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121.
Post exercise lymphocytopenia is well documented and attributed to egress of lymphocytes from the vascular compartment. Recent studies have reported exercise induced DNA damage in leukocytes and have questioned a possible link to apoptosis. Eleven subjects underwent a ramped treadmill test to exhaustion. Venous blood samples were taken before, immediately post exercise, and 24 and 48 hours after exercise. Single cell gel electrophoresis revealed evidence of single strand DNA damage in 10% of lymphocytes immediately after exercise, but not at other times. Fluorescent microscopy showed three patterns of DNA distribution, similar to those seen in apoptosis, at all times after exercise. Three subjects underwent the same exercise protocol, and lymphocytes were prepared for flow cytometry to determine apoptosis using the TUNEL method. Flow cytometry revealed lymphocyte apoptosis in 63% of lymphocytes immediately after exercise and 86.2%, 24 hours after exercise. Lymphocyte apoptosis is documented for the first time after exercise and may in part account for exercise induced lymphocytopenia and reduced immunity. 相似文献
122.
Radiographic computed tomography and magnetic resonance imaging are the procedures of choice in the diagnosis of patients with suspected pituitary gland abnormalities. Several cases are presented where the diagnostic value of such procedures in patients with diseases affecting the pituitary gland is demonstrated. 相似文献
123.
GW Moore JJ Berman RL Hanzlick JJ Buchino GM Hutchins 《Canadian Metallurgical Quarterly》1996,120(8):782-785
OBJECTIVE: To demonstrate that cause-of-death statements can be generated by a computer algorithm from an autopsy database composed of diagnostic terms. DATA SOURCES: Over 49 000 autopsy facesheets contributed by over a dozen institutions were collected from a publicly accessible Internet autopsy database. This database is available at the following web site: http:@www.med.jhu.edu/pathology/iad.html STUDY SELECTION: To test the feasibility of creating and using a publicly available autopsy database, and to identify the technical and medicolegal problems that may arise with such a novel resource, a prototype study was designed by selecting autopsy facesheets from fetal and neonatal deaths. An algorithm was developed to determine the cause of death from the listing of anatomic diagnoses. DATA EXTRACTION: One thousand six hundred twenty-five fetal and neonatal autopsy facesheets were selected encompassing fetal and neonatal deaths occurring up to 28 days after birth. DATA SYNTHESIS: The algorithm determined causes of death from autopsy facesheet data in all cases. On review by an experienced pediatric pathologist, these automatically generated cause-of-death statements required no modification or only slight modification in over 90% of cases. CONCLUSIONS: A large multi-institutional autopsy database composed of demographic and diagnostic information has been deposited on the Internet. This information can be freely downloaded and used by any researcher without violating patient confidentiality. As a demonstration of one possible application of the database, fetal and neonatal autopsies generated cause-of-death statements using a computer algorithm. One can anticipate that the wealth of information contained in autopsy facesheets can be assembled into a database that will serve the public interest. 相似文献
124.
KL Houseknecht CA Baile RL Matteri ME Spurlock 《Canadian Metallurgical Quarterly》1998,76(5):1405-1420
Leptin, a 16-kDa protein secreted from white adipocytes, has been implicated in the regulation of food intake, energy expenditure, and whole-body energy balance in rodents and humans. The gene encoding leptin was identified by positional cloning and is the mutation leading to the profound obese phenotype of the ob/ob mouse. Exogenous administration of leptin to ob/ob mice leads to a significant improvement in reproductive and endocrine status as well as reduced food intake and weight loss. The expression and secretion of leptin is highly correlated with body fat mass and adipocyte size. Cortisol and insulin are potent stimulators of leptin expression, and expression is attenuated by beta-adrenergic agonists, cAMP, and thiazolidinediones. The role of other hormones and growth factors in the regulation of leptin expression and secretion is emerging. Leptin circulates specifically bound to proteins in serum, which may regulate its half-life and biological activity. Isoforms of the leptin receptor, members of the interleukin-6 cytokine family of receptors, are found in multiple tissues, including the brain. Many of leptin's effects on food intake and energy expenditure are thought to be mediated centrally via neurotransmitters such as neuropeptide Y. Multiple peripheral effects of leptin have also been recently described, including the regulation of insulin secretion by pancreatic beta cells and regulation of insulin action and energy metabolism in adipocytes and skeletal muscle. Leptin is thought to be a metabolic signal that regulates nutritional status effects on reproductive function. Leptin also plays a major role in hematopoeisis and in the anorexia accompanying an acute cytokine challenge. The profound effects of leptin on regulating body energy balance make it a prime candidate for drug therapies for humans and animals. 相似文献
125.
PURPOSE: To describe the development of an instrument to measure women's knowledge of osteoporosis based on Orem's self-care theory and the latest clinical research on osteoporosis. SAMPLE: One hundred and four women from four groups including graduate and undergraduate nursing students, sociology students, and a community sample, completed the instrument. METHODS: Items for the instrument were developed from three objectives related to osteoporosis risk factors, known facts and preventive behaviors. There were 34 items on the original instrument. It was content validated by experts and subjected to item analysis. The report contains a copy of the instrument with the theoretical classification and item analysis. FINDINGS: The Facts on Osteoporosis Quiz had a content validity index of .92, a reliability of .83 and a reading level of sixth grade. Item difficulty and item discrimination were used to delete items. The final instrument contains 25 items. CONCLUSION: The quiz is a simple, inexpensive measure that can be used in various settings by nurses to assess women's knowledge of self-care in osteoporosis. 相似文献
126.
127.
NC Schattenfroh RA Hoffman SA McCarthy RL Simmons 《Canadian Metallurgical Quarterly》1995,59(2):268-273
A pyriform sinus fistula can cause acute thyroiditis or recurrent infection in the neck. This fistula is believed to be a remnant of the branchial apparatus, although its origin has yet to be pinpointed. The spatial distribution of C cells in the thyroid gland was mapped by immunohistologic method in four patients with a pyriform sinus fistula. The C cells were identified immunohistologically with anticalcitonin antibody. The stained calcitonin-positive cells also crossreacted with the antibodies to carcinoembryonic antigen, chromogranin A, and neuron-specific enolase. The C cells were mainly distributed near the end of the fistula, and in three patients their concentration per unit volume of thyroid tissue was found to be inversely proportional to the distance from the end of the fistulas. Comparison of distant locations of the left-sided thyroid lobe in patients and the same region in control subjects showed a similar number of C cells. Thus this limited distribution of C cells suggested that the pyriform sinus fistula was either a remnant of the ultimobranchial body, the result of disturbed migration of the C cell in the fetus, or both. 相似文献
128.
The recently developed procedure of chromosomal DNA loop excision by topoisomerase II-mediated DNA cleavage at matrix attachment sites (S. V. Razin, R. Hancock, O. Iarovaia, O. Westergaard, I. Gromova, and G. P. Georgiev, Cold Spring Harbor Symp. Quant. Biol. 58:25-35, 1993; I. I. Gromova, B. Thompsen, and S. V. Razin, Proc. Natl. Acad. Sci. USA 92:102-106, 1995) has been employed for mapping the DNA loop anchorage sites in a 500-kb region of the Drosophila melanogaster X chromosome. Eleven anchorage sites delimiting 10 DNA loops ranging in size from 20 to 90 kb were found within this region. Ten of these 11 anchorage sites colocalize with previously mapped scaffold attachment regions. However, a number of other scaffold attachment regions are found to be located in loop DNA. 相似文献
129.
MA Charles DJ Pettitt RL Hanson PH Bennett MF Saad QZ Liu WC Knowler 《Canadian Metallurgical Quarterly》1994,140(2):123-131
High blood pressure, abnormal glucose tolerance, and obesity are frequently associated with each other, but the mechanism of these associations is poorly understood. Studying them in children may help in understanding the pathogenesis of hypertension. Blood pressure, height, weight, and plasma glucose and serum insulin concentrations during a 75-g oral glucose tolerance test were measured in 1,698 Pima Indian children aged 6-17 years who participated in an ongoing epidemiologic study. Weight relative to height was used as an index of obesity. The parents of many of the children were also examined. Fasting and 2-hour glucose and insulin concentrations, adjusted for age, sex, and relative weight, were positively related to systolic blood pressure but not to diastolic blood pressure. Relative weight, 2-hour glucose, and fasting insulin concentrations were independently and significantly associated with systolic blood pressure in a stepwise regression analysis that included age and sex. After parental hypertension was taken into account, maternal but not paternal non-insulin-dependent diabetes mellitus, controlled for the child's relative weight and glucose and insulin concentrations, was significantly associated with higher blood pressure in children. The stronger association with maternal diabetes suggests a greater sharing of environmental factors between mother and child than between father and child, but familial similarities in obesity and glucose and insulin concentrations, the diabetic intrauterine milieu, and shared environmental factors probably all contribute to this association. 相似文献
130.
F Liao RL Rabin JR Yannelli LG Koniaris P Vanguri JM Farber 《Canadian Metallurgical Quarterly》1995,182(5):1301-1314
Mig is a chemokine of the CXC subfamily that was discovered by differential screening of a cDNA library prepared from lymphokine-activated macrophages. The mig gene is inducible in macrophages and in other cells in response to interferon (IFN)-gamma. We have transfected Chinese hamster ovary (CHO) cells with cDNA encoding human Mig and we have derived CHO cell lines from which we have purified recombinant human Mig (rHuMig). rHuMig induced the transient elevation of [Ca2+]i in human tumor-infiltrating T lymphocytes (TIL) and in cultured, activated human peripheral blood-derived lymphocytes. No responses were seen in human neutrophils, monocytes, or Epstein-Barr virus-transformed B lymphoblastoid cell lines. rHuMig was chemotactic for TIL by a modified Boyden chamber assay but rHuMig was not chemotactic for neutrophils or monocytes. The CHO cell lines, IFN-gamma-treated human peripheral-blood monocytes, and IFN-gamma-treated cells of the human monocytic cell line THP-1 all secreted multiple and identical HuMig species as revealed by SDS-PAGE. Using the CHO-derived rHuMig, we have shown that the species' heterogeneity is due to proteolytic cleavage at basic carboxy-terminal residues, and that the proteolysis occurs before and not after rHuMig secretion by the CHO cells. The major species of secreted rHuMig ranged from 78 to 103 amino acids in length, the latter corresponding to the full-length secreted protein predicted from the HuMig cDNA. Carboxy-terminal-truncated forms of rHuMig were of lower specific activity compared to full-length rHuMig in the calcium flux assay, and the truncated species did not block the activity of the full-length species. It is likely that HuMig plays a role in T cell trafficking and perhaps in other aspects of the physiology of activated T cells. 相似文献