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排序方式: 共有861条查询结果,搜索用时 484 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
2.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
3.
H. R. Rosen W. Feil G. Novi G. Zöch S. Dahlberg R. Schiessel 《International journal of colorectal disease》1994,9(4):184-186
Continence following the gracilis stimulated neosphincter reconstruction after total rectal excision is inferior to that obtained in the presence of an intact anal canal. We describe a modification of the alpha loop in which the tendon is brought through the belly of the gracilis muscle. The results in three patients are presented.
Résumé La reconstruction sphinctérienne après excision totale du rectum au moyen d'un néosphincter fait d'un muscle gracilis stimulé donne des résultats sur le plan de la continence inférieurs à ceux obtenus en présence d'un canal anal intact. Nous décrivons une modification de l'anse alpha dans laquelle le tendon est fixé après avoir traversé la sangle de muscle gracilis. Les résultats de trois patients sont rapportés.相似文献
4.
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses. 相似文献
5.
Both in open and in closed elbow fractures, anatomical joint reconstruction and rigid internal fixation, which permit early initiation of motion, are essential for good joint function. However, in open distal intraarticular humerus fractures this is more difficult to achieve, owing to the high rate of comminuted types C 2 and C 3 fractures. In addition, the extensive soft tissue lesions often mean that physiotherapy cannot be started until later than would otherwise be desirable. This retrospective study shows that the functional results in 60 patients operated on for correction of open distal intraarticular humerus fractures were worse (1/3 "excellent/good", 2/3 "moderate/poor") than those in patients treated for closed fractures. Complications included superficial infection in 7 patients, osteitis in 11, late instability in 10, fatigue failure of the implants in 5, and non-union in 10 patients. 相似文献
6.
Jolley KA Kalmusova J Feil EJ Gupta S Musilek M Kriz P Maiden MC 《Journal of clinical microbiology》2000,38(12):4492-4498
Population and evolutionary analyses of pathogenic bacteria are frequently hindered by sampling strategies that concentrate on isolates from patients with invasive disease. This is especially so for the gram-negative diplococcus Neisseria meningitidis, a cause of septicemia and meningitis worldwide. Meningococcal isolate collections almost exclusively comprise organisms originating from patients with invasive meningococcal disease, although this bacterium is a commensal inhabitant of the human nasopharynx and very rarely causes pathological effects. In the present study, molecular biology-based techniques were used to establish the genetic relationships of 156 meningococci isolated from healthy young adults in the Czech Republic during 1993. None of the individuals sampled had known links to patients with invasive disease. Multilocus sequence typing (MLST) showed that the bacterial population was highly diverse, comprising 71 different sequence types (STs) which were assigned to 34 distinct complexes or lineages. Three previously identified hyperinvasive lineages were present: 26 isolates (17%) belonged to the ST-41 complex (lineage 3); 4 (2.6%) belonged to the ST-11 (electrophoretic type [ET-37]) complex, and 1 (0.6%) belonged to the ST-32 (ET-5) complex. The data were consistent with the view that most nucleotide sequence diversity resulted from the reassortment of alleles by horizontal genetic exchange. 相似文献
7.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
8.
Guidelines for the validation and application of typing methods for use in bacterial epidemiology 总被引:3,自引:0,他引:3
A. van Belkum P. T. Tassios L. Dijkshoorn S. Haeggman B. Cookson N. K. Fry V. Fussing J. Green E. Feil P. Gerner-Smidt S. Brisse M. Struelens for the European Society of Clinical Microbiology Infectious Diseases Study Group on Epidemiological Markers 《Clinical microbiology and infection》2007,13(S3):1-46
9.
Feil S Zimmermann P Knorn A Brummer S Schlossmann J Hofmann F Feil R 《Neuroscience》2005,135(3):863-868
Nitric oxide (NO) modulates a variety of processes in the mammalian brain, but the mechanisms of neuronal NO signaling are poorly understood. In the periphery, many effects of NO are mediated via the generation of the second messenger cyclic guanosine-3',5'-monophosphate (cGMP) and activation of the cGMP-dependent protein kinase type I (cGKI). However, previous studies suggested that the expression of cGKI in the nervous system is rather restricted, thus, questioning the functional significance of the cGMP/cGKI pathway as a mediator of NO signaling in the brain. Here we have performed a detailed immunohistochemical study to elucidate the distribution of cGKI in the CNS and eye of the mouse. Expression of cGKI protein was detected not only in the previously described areas (cerebellum, hippocampus, dorsomedial hypothalamus) but also in a number of additional regions, such as medulla, subcommissural organ, cerebral cortex, amygdala, habenulae, various hypothalamic regions, olfactory bulb, pituitary gland, and retina. Immunoblotting with isoform-specific antibodies indicated that the cGKIalpha isoform is prominent in the cerebellum and medulla, whereas the cGKIbeta isoform is predominant in the cortex, hippocampus, hypothalamus, and olfactory bulb. Similar levels of the isoforms were detected in the pituitary gland and eye. Thus, it appears that distinct brain regions express distinct cGKI isoforms that signal via distinct pathways. Together, these results improve our understanding of the cellular and molecular mechanisms of NO/cGMP/cGKI signaling and indicate that the distribution and functional relevance of this pathway in the mammalian brain is broader than previously thought. 相似文献
10.