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991.
H. Fjeldsøe-Nielsen M. Unemo H. Fredlund S. V. Hjorth L. M. Berthelsen H. M. Palmer A. Friis-Møller 《European journal of clinical microbiology & infectious diseases》2005,24(4):280-283
In the study presented here 26 recent Danish clinical isolates of prolyliminopeptidase (PIP)-negative Neisseria gonorrhoeae were phenotypically and genotypically characterized to investigate whether one or more PIP-negative strains are circulating in the Danish community. The profiles of these isolates were compared with those of three isolates from a recent outbreak of PIP-negative N. gonorrhoeae infection in the UK. Twenty-five of the Danish isolates and all three UK isolates had similar antibiograms and were designated serovar IB-4. Genotypic characterization by pulsed-field gel electrophoresis, porB1b gene sequencing, and opa-typing revealed that these isolates were indistinguishable or closely related. The results indicate that at least one PIP-negative N. gonorrhoeae strain is currently circulating in the Danish community, and this strain is indistinguishable from the one that caused an outbreak in the UK.An erratum to this article can be found at 相似文献
992.
The absolute activities of the pure beta-emitters 89Sr and 90Y have been determined by a direct method, namely the triple-to-double coincidence ratio (TDCR) efficiency calculation technique. This undertaking has extended further the number of radionuclides that have been standardized by this non-extrapolation liquid scintillation (LS) method. Both measurements were carried out within the framework of international key comparisons under the auspices of the International Bureau of Weights and Measures (BIPM). The TDCR results agreed well with those of other participating national laboratories, most using alternative (tracer) methods. 相似文献
993.
100 years of ‘Allergy’: can von Pirquet's word be rescued? 总被引:1,自引:0,他引:1
A. B. Kay 《Clinical and experimental allergy》2006,36(5):555-559
Summary It is 100 years since Clemens von Pirquet wrote his classic paper introducing the term 'allergy'. Although the word is no longer used in the way he intended, his concept of 'changed reactivity' laid the foundation for the modern science of immunology. 相似文献
994.
995.
M. M. Marchenko G. P. Kopyl’chuk I. A. Shmarakov O. V. Ketsa V. N. Kushnir 《Pharmaceutical Chemistry Journal》2006,40(6):296-297
The antitumor activity of 5-(5′,6′-benzocoumaro-3′-yl)methylaminouracil (BCMU) and its liposomal medicinal form was studied
in comparison to 5-fluorouracil (5-FU), a well-known antitumor drug widely used in oncological practice. The half-lethal dose
of BCMU is 14.8 ± 4.2 mg/kg, while the optimum effective dose of the drug is 6 mg/kg. In this dose, BCMU combines low toxicity
with significant antitumor activity, which is manifested by increased tumor growth inhibition (TGI) at a 19% increase in the
lifetime (LT) of experimental animals. The antitumor activity of the liposomal form of BCMU is quantitatively and qualitatively
superior to that of the nonmodified compound and 5-FU, which is manifested by the most pronounced TGI value and by a significant
LT increase.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 6, pp. 6–7, June, 2006. 相似文献
996.
Noriyoshi Kurihara Hua Zhou Sakamuri V Reddy Veronica Garcia Palacios Mark A Subler David W Dempster Jolene J Windle G David Roodman 《Journal of bone and mineral research》2006,21(3):446-455
We targeted the MVNP gene to the OCL lineage in transgenic mice. These mice developed abnormal OCLs and bone lesions similar to those found in Paget's patients. These results show that persistent expression of MVNP in OCLs can induce pagetic-like bone lesions in vivo. INTRODUCTION: Paget's disease (PD) of bone is the second most common bone disease. Both genetic and viral factors have been implicated in its pathogenesis, but their exact roles in vivo are unclear. We previously reported that transfection of normal human osteoclast (OCL) precursors with the measles virus nucleocapsid (MVNP) or measles virus (MV) infection of bone marrow cells from transgenic mice expressing a MV receptor results in formation of pagetic-like OCLs. MATERIALS AND METHODS: Based on these in vitro studies, we determined if the MVNP gene from either an Edmonston-related strain of MV or a MVNP gene sequence derived from a patient with PD (P-MVNP), when targeted to cells in the OCL lineage of transgenic mice with the TRACP promoter (TRACP/MVNP mice), induced changes in bone similar to those found in PD. RESULTS: Bone marrow culture studies and histomorphometric analysis of bones from these mice showed that their OCLs displayed many of the features of pagetic OCLs and that they developed bone lesions that were similar to those in patients with PD. Furthermore, IL-6 seemed to be required for the development of the pagetic phenotype in OCLs from TRACP/MVNP mice. CONCLUSIONS: These results show that persistent expression of the MVNP gene in cells of the OCL lineage can induce pagetic-like bone lesions in vivo. 相似文献
997.
Priv.-Doz. Dr. Rüdiger Dissmann Joachim Schröder MD PhD Prof. Dr. med. Heinz Völler Prof. Dr. med. Steffen Behrens 《Clinical research in cardiology》2006,95(4):241-243
Summary During pacemaker implantation in a patient with permanent atrial fibrillation, it remained impossible to advance a passive
fixation lead with fins through the right atrium. However, a lead with a retractable screw easily passed the right atrium
and was positioned in the right ventricle. Transesophageal echocardiography revealed an extensive net–like perforated Eustachian
valve within the right atrium that had caused entrapment of the anchor fins during lead implantation. Remnants of embryonal
structures within the right atrium should be considered a rare possible barrier during pacemaker implantation. 相似文献
998.
S Nazifi A. Rowshan Ghasrodashti K. Badiei A. Mahjoor B. Nikahval 《Comparative clinical pathology》2005,13(3):142-146
A 5-year-old Iranian fat-tailed sheep was referred to the Veterinary Clinic of Shiraz University in September 2003 with a history of emaciation, fever, decreased appetite, lethargy and cough. Small cutaneous and subcutaneous nodules were palpable, especially under the ribs on both sides of the thorax. Discrete cutaneous plaques and large scabby lesions were also observed. Very large mammary gland lymph nodes were noticed on palpation. Haematological and serum biochemical values were estimated through standard haematological and biochemical techniques. In this case a normocytic–normochromic anaemia, leukocytosis and lymphocytosis were found. The concentrations of blood urea nitrogen (BUN), creatinine, cholesterol and the activities of aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) were higher than the values reported for sheep. Necropsy findings revealed that the lymph nodes were affected in most organs. Malignant lymphoma in the kidney, heart, spleen, mammary glands, liver and bone marrow was observed. The histopathological appearance of the affected tissues varied considerably, depending upon the degree of tumour infiltration. According to the history, clinical signs, laboratory findings, necropsy findings and histopathological examination the case was diagnosed as chronic lymphocytic leukaemia and lymphoma. 相似文献
999.
Factors influencing family physicians to enter rural practice: Does rural or urban background make a difference? 下载免费PDF全文
1000.
Design of Case-controls Studies with Unscreened Controls 总被引:2,自引:0,他引:2
Traditionally in genetic case‐control studies controls have been screened to exclude subjects with a personal history of illness. This control group has the advantage of optimal power to detect loci involved in illness, but requires more work and may incur substantial cost in recruitment. An alternative approach to screening is to use unscreened controls sampled from the general population. Such controls are generally plentiful and inexpensive, but in general there is a risk that some may have the same disease as the cases, which will reduce power to detect associations. We have quantified the extent of this power loss, and produced mathematical formulae for the number of unscreened controls necessary to achieve the same power as a fixed sample of screened controls. The effect of using unscreened controls will also depend on the ratio of the number of screened controls to cases specified in the original study design, and this is also investigated. We have also investigated the cost‐benefits of the screened and unscreened approaches, according to variation in the relative costs of sampling screened and unscreened controls, together with genotyping costs. We have, thus, identified the range of situations in which using unscreened controls is a cost‐effective alternative to the screened control method and could be considered when designing a study. In many of the typical, real‐world situations in complex genetics, the use of unscreened controls is potentially cost‐effective and can, in general, be considered for disorders with population prevalence Kp < 0.2. With the steady reduction in genotyping costs and the availability of common sets of “population controls” this design is likely to become increasingly cost effective. 相似文献