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51.
Markus Kohler Hans M. Eppenberger Imogen Cordt-Riehle Christian Michel 《Acta oncologica (Stockholm, Sweden)》1992,31(6):673-677
Urination frequency and cystic pressure resistance have been used as end-points to assess x-ray-induced changes of bladder function. Whole or half bladders of adult male rabbits were irradiated, caudally or cranially. The absorbed dose was 33 Gy, 36 Gy or 39 Gy, given in 5 daily fractions. Animals which received a whole bladder dose of 39 Gy or 36 Gy showed increased urination frequency and enhanced bladder pressure resistance during the whole follow-up time of 100 weeks, compared with the sham-irradiated controls. At half bladder irradiation, only the highest doses (39 Gy to the cranial part of the bladder and 39 Gy or 36 Gy to the caudal part) gave rise to a slight increase in frequency at about 20 weeks after exposure. 相似文献
52.
J C Marshall C Lee J L Meakins R P Michel N V Christou 《Archives of surgery (Chicago, Ill. : 1960)》1987,122(2):191-196
The effects of global hepatic injury and of Kupffer cell activation on systemic immunity were studied in an in vivo rat model, using the diameters of the delayed-type hypersensitivity (DTH) response to keyhole limpet hemocyanin and of a subcutaneous Staphylococcus aureus abscess as measures of systemic immunoresponsiveness. Hepatic injury with carbon tetrachloride resulted in significant suppression of the DTH score (5.5 +/- 0.7 vs 8.8 +/- 0.8 mm). Kupffer cell activation with intraportal Escherichia coli was likewise suppressive (DTH score, 4.4 +/- 0.5 vs 6.1 +/- 0.4 mm for animals receiving systemic E coli); the magnitude of this suppression correlated with the numbers of organisms extracted by the liver. Conversely, Kupffer cell ablation with carrageenan lessened the immunosuppressive effects of anesthesia and surgery (DTH score, 8.5 +/- 0.9 vs 6.8 +/- 0.6 mm for controls; S aureus abscess, 4.1 +/- 0.4 vs 5.7 +/- 0.4 mm for controls). These results indicate that Kupffer cells can modulate the systemic immune response and suggest that gram-negative portal bacteremia with resultant Kupffer cell activation may contribute to the immunologic derangements characteristic of trauma and critical surgical illness. 相似文献
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Antonietta C. Rouget MD Reuben A. Lang PhD Michel R. Joffres MD 《Sexual abuse : a journal of research and treatment》1988,1(1):95-114
The prevalence of abnormal physical signs (e.g., bleeding, scars, or bruises) and genital infections, notably Chlamydia Trachomatis, Neisseria Gonorrhea, and Herpes Simplex Genitalis was studied in 219 female children with validated sexual abuse. They were compared to 113 nonabused female children. The average abused child was 8.3 years old, with 69% having been abused on multiple occasions. Most offenders were family members (65%) or a close family friend (22%). Stranger-perpetrated sexual assault, in the sample, was low (9.1%). Few children had severe vaginal tears, though 56% showed signs of subtle anatomical injury to their genitalia. No similar anatomical abnormalities were present in nonabused children. Among the sexually abused children and adolescents, 35% were colonized with a pathogen or a potential pathogen, compared to a prevalence rate of 18.5% in non-abused children. The proportion of abused children colonized with Ureaplasma Urealyticum and Mycoplasma Hominis was not significantly different from that found in nonabused children. At present, Neisseria gonorrhea and Chlamydia Trachomatis remain the only conclusive markers for sexual abuse. It is recommended that routine cultures of the pharyngeal, rectal, and vaginal areas be taken in all cases of suspected child sexual abuse, regardless of clinical findings. 相似文献
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OBJECTIVE: To know the range of changes of compound muscle action potentials (CMAPs) in the muscles innervated by the ulnar nerve after diverse provocative tests, 14 healthy patients were studied with the same protocol. METHODS: CMAPs were measured at rest, just after a short exercise test (SET), during short 5 and 10c/s repetitive nerve stimulation (RNS) trains, at approximately 32 and approximately 20 degrees C. RESULTS: At 32 degrees C, the SET induced a significant but transient enlargement of the CMAPs (amplitude increased by 8.3%, duration decreased by 9%) that was only partially reproduced by RNS trains, except for a significant shortening of the CMAPs at 10c/s. At 20 degrees C without exercise, CMAPs increased significantly by approximately 30% in amplitude, duration and area, and after the SET the inverse of what has been seen at 32 degrees C was observed (amplitude decreased by 1.7% and duration increased by 9%). RNS at 20 degrees C produced a marked interpatient heterogeneity except for a significant shortening of the CMAPs at 10c/s. In one pure autonomic failure patient, the infusion of norepinephrine induced potentiation of the responses at rest and a decrease in the expected changes after provocative tests. CONCLUSIONS: CMAP amplitude and duration are significantly modified just after the SET at 32 degrees C, at rest at 20 degrees C and after RNS at 10c/s but not at 5c/s. Although providing indirect evidence, these findings indicate that provocative tests make the muscle membrane hyperexcitable by the way of a direct influence on the electrical events and by an indirect local catecholamine spillover. 相似文献
58.
Emmanuelle Ponty Michel Carton Georges Soula Gillcs Favre Rachid Benaniba Andre Boneu Henriette Lucot 《International journal of cancer. Journal international du cancer》1993,54(3):411-417
Since there is strong evidence of a preferential LDL accumulation in tumor cells, LDL might be of interest for tumor imaging. We have tested the ability of 99mTc-LDL in tumor imaging with B16-melanoma-bearing mice as a model for further applications in human studies. The LDL fixation rate was higher with 99mTc-labeled LDL than with 125I labeled LDL. Since technetium-99m remains trapped in the cells, 99mTc-LDL is a well-adapted radioligand because of information given by this radiotracer on the receptor metabolism. We observed that, at early growth stages, the tumor took up the LDL at a maximal rate, suggesting differences in cholesterol metabolism as a function of tumor growth. Accumulation of label in the tumor area was perfectly observable in tumor-bearing mice on scintigraphic images. Computerized quantification of the regions of interest (as well as biodistribution studies including killing of the animals) showed a 1.81 -fold increase in uptake by the tumor as compared to the liver and a 28-fold increase as compared with corresponding normal tissue (muscle of the left leg) at day 8 of tumor growth. These data give strong support to the value of this non-invasive method in visualizing and quantifying the tissue LDL uptake in vivo, including the precise information provided by nuclear scintigraphy on the distribution of the radiolabeled LDL in the different tissues. 99mTc-LDL could be an efficient tool for further diagnostic or therapeutic exploration in cancer patients. 相似文献
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We evaluated retrospectively the varying radiographic appearances of 15 solitary lucent epiphyseal lesions occurring in children. Imaging modalities used included plain films, conventional tomography, nuclear scintigraphy, and computed tomography. Forty percent of the lesions (6) were due to osteomyelitis. The remaining lesions included tuberculosis (1), foreign body granuloma (1), chondroblastoma (2), chondromyxoid fibroma (1), enchondroma (1), osteoid osteoma (2), and eosinophilic granuloma (1). Although the radiographic appearances of such lesions may be particularly characteristic, pathologic correlation is frequently necessary. The high incidence of osteomyelitis in our cases emphasizes its importance as a cause for a lucent epiphyseal lesion. 相似文献