What terms can be applied to mycobacteria other than M. tuberculosis and M. leprae

A review of the terms used to name mycobacteria other than M. tuberculosis and M. leprae was performed. A system using binomial nomenclature is defended. The author comments on the various names applied to mycobacteria over the history of medicine, from 1899 to the present, and the reasons why terms such as environmental mycobacteria or nontuberculous mycobacteria are incorrect and should not be used. In the case that a general name must be chosen for these mycobacteria, the term atypical mycobacteria is advocated.     

基因芯片技术在脑损伤研究中的应用

基因芯片技术是最近发展起来的新兴分子生物学技术,它的并行处理特点使大规模研究脑损伤后的基因改变成为切实可能。本文综述了新近用基因芯片技术在脑损伤后基因表达时序性改变及基因表达谱分析等研究中的应用。     

Results of randomized controlled trials of low-versus high-osmolality contrast media

The authors reviewed 100 randomized controlled trials (RCTs) conducted in humans to compare safety or efficacy of new low-osmolality contrast media (LOM) with that of high-osmolality contrast media (HOM). Findings of the 43 RCTs judged to be of the highest quality suggest that the efficacy of LOM in imaging is equal or superior to that of HOM for all routes of administration. Heat sensation occurred less often with LOM for all routes and pain occurred less often with LOM for intraarterial routes. No differences were seen in nephrotoxicity or in frequency of nausea, vomiting, urticaria, bronchospasm, laboratory test abnormalities, or neurologic events. Greater cardiovascular changes were seen with HOM, including increased or decreased heart rate, increased left ventricular end-diastolic pressure, decreased systolic pressure, and QT prolongation, depending on route of administration. To demonstrate whether a reduction in clinically significant adverse outcomes truly occurs with LOM, trials will need to enlist larger numbers of patients and employ appropriate outcome measures. Future trials should stratify patients according to their risk of adverse reactions to provide better information about benefits of LOM in low- versus high-risk patients.     

Isthmic spondylolysis of the lumbar spine: MR imaging at 1.5 T

The appearance on magnetic resonance (MR) images of the normal pars interarticularis in 13 patients was reviewed and contrasted with that of the pars in eight patients with spondylolysis. The pars defect usually had an intermediate signal intensity with all pulse sequences; however, this intensity was somewhat variable depending on the exact ratio of cartilage, fat, and fluid within each bone defect. The pars defect was best seen with spin-echo 600/20 (repetition time msec/echo time msec) images. In three cases, out-of-phase images showed the spondylolysis best, because of extension of fat to the borders of the defect. The sagittal view allowed one to separate spondylolysis from the joint space of posterior facets since the orientation of the defects is perpendicular to the facets; thus, a common pitfall encountered with cross-sectional axial imaging techniques is avoided. MR imaging poorly delineated bone fragments around the defect, which may produce nerve root impingement, but revealed other numerous complications that occur with spondylolysis, including spondylolisthesis and herniation of the disk above.     

Bell-like homeodomain selectively regulates the high-irradiance response of phytochrome A

Plant responses mediated by phytochrome A display a first phase saturated by transient light signals and a second phase requiring sustained excitation with far-red light (FR). These discrete outcomes, respectively so-called very-low-fluence response (VLFR) and high-irradiance response (HIR), are appropriate in different environmental and developmental contexts but the mechanisms that regulate the switch remain unexplored. Promoter analysis of a light-responsive target gene revealed a motif necessary for HIR but not for VLFR. This motif is required for binding of the Bell-like homeodomain 1 (BLH1) to the promoter in in vitro and in yeast 1-hybrid experiments. Promoter substitutions that increased BLH1 binding also enhanced HIR. blh1 mutants showed reduced responses to continuous FR and to deep canopy shadelight, but they retained normal responses to pulsed FR or red light and unfiltered sunlight. BLH1 enhanced BLH1 expression and its promotion by FR. We conclude that BLH1 specifically regulates HIR and not VLFR of phytochrome A.     

Transabdominal versus endovaginal pelvic sonography: prospective study

Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography.     

Precise intraoperative location of gastrointestinal bleeding with a hand-held counter. Work in progress

The nuclear medicine bleeding scan is frequently insufficient to locate sites of bleeding precisely, in spite of its great sensitivity. A small, hand-held Geiger-Müller counter, placed directly on exposed intestine in the operating room, enables precise location of the probable bleeding site. In three patients, the technique allowed a minimal amount of intestine to be resected, distinguished between large- and small-intestinal hemorrhage, and eliminated other foci as sites of bleeding.