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The patellofemoral joint was imaged with magnetic resonance (MR) in the axial plane while the knee was positioned from 0 degrees to 32 degrees of flexion (nine positions). These multiple sequential images obtained within the early phases of flexion of the knee were viewed in a "cine-loop" format, producing a kinematic study that clearly demonstrated the relationship of the patella to the trochlear groove. Four healthy subjects and one patient with known bilateral subluxing patellae were studied. The preliminary results suggest that kinematic MR imaging of the patellofemoral joint is potentially useful for the evaluation of patellar tracking abnormalities. 相似文献
23.
S. C. Park W. H. Kim M. C. Lee S. C. Seong K. Y. Song M. A. Choe 《Journal of Korean medical science》1994,9(6):490-496
The persistence of muscle fiber number regardless of size reduction in muscle atrophy has not yet been fully explained. For the mechanism inherent in skeletal muscle tissues for preventing cellular death, the protective function of muscle tissue through transglutaminases has been tested, since the enzyme is responsible for structural stabilization and participates in signal transduction. In the present experiment, hindlimb suspension for two weeks caused a marked muscle atrophy in Wistar female rats. Comparison of muscle weight and histological analysis showed that suspension-induced atrophy in the hindlimb was more prominent in the soleus muscle, comprised mainly of type I fiber than that in the plantaris muscle of type II fibers. The immunohistochemical analysis with antitransglutaminase C antibody (anti TGase C Ab) showed that some atrophic bundles of soleus muscle were positively reacted with the antibody. The anti-TGase C Ab-reactive substances were observed to disappear significantly after endurance exercise, indicating their characteristic atrophy-dependency. The enzymatic analysis of transglutaminase showed the increase in activity in the atrophic soleus muscle tissue, compared with that in the normal or exercise-trained muscle tissues. From these results, the expression of TGase in the atrophic muscle is suggested to be the possible marker for muscle atrophy and its expression is probably related with the protective mechanism of the muscle tissue to prevent further cellular damage in the atrophic process. 相似文献
24.
Diffuse optical tomography of breast cancer during neoadjuvant chemotherapy: a case study with comparison to MRI 总被引:1,自引:0,他引:1
Choe R Corlu A Lee K Durduran T Konecky SD Grosicka-Koptyra M Arridge SR Czerniecki BJ Fraker DL DeMichele A Chance B Rosen MA Yodh AG 《Medical physics》2005,32(4):1128-1139
We employ diffuse optical tomography (DOT) to track treatment progress in a female subject presenting with locally advanced invasive carcinoma of the breast during neoadjuvant chemotherapy. Three-dimensional images of total hemoglobin concentration and scattering identified the tumor. Our measurements reveal tumor shrinkage during the course of chemotherapy, in reasonable agreement with magnetic resonance images of the same subject. A decrease in total hemoglobin concentration contrast between tumor and normal tissue was also observed over time. The results demonstrate the potential of DOT for measuring physiological parameters of breast lesions during chemotherapy. 相似文献
25.
Hybrid cell lines producing monoclonal antibodies against human prostatic acid phosphatase (E. C. 3.1.3.2) were prepared by the fusion of mouse myeloma cells with the spleen cells of BALB/c mice and Lewis rats immunized with prostatic acid phosphatase (PAP). Approximately 14% of the hybrid cell microcultures which produced specific antibodies were cloned, and 6 eventually yielded stable cell lines. The monoclonal antibodies produced by these 6 hybridomas were characterized for their isotypes, isoelectric points, concentrations and affinities. The specificity of these monoclonal antibodies was further investigated by radioimmunoassay and immunohistochemical methods. All of the 6 monoclonal antibodies exhibited strict specificity for prostatic acid phosphatase. 相似文献
26.
Three cases of microcystic adenomas of the pancreas with special reference to multicentric origin are described. The gross features and light microscopic findings were consistent with those described as being microcystic adenomas, but in two cases the gross examination and gelatin-embedded giant slices revealed multiple, isolated development of tumors ranging from submacroscopic nodules to tumors 4.5 cm in diameter. The larger tumors often showed ragged margins with small satellite nodules around the masses. A central fibrolamellar stellate core with centrifugally radiating septation was found in most of the tumor masses, even in the smaller ones. Ultrastructural and immunohistochemical findings revealed a single row of glycogen-rich epithelial cells, but participation of myoepithelial cells was not confirmed. Instead, vimentin-positive cells (pericytes) within the interstitial space incorporated closely with the basal lamina of the cyst wall. This study suggests that a small percentage of microcystic adenomas of the pancreas develop in multiple tumors, and some appear as a single tumor by their confluence. 相似文献
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Hyperreactio luteinalis is characterized by moderate to marked cystic enlargement of the ovaries related to multiple theca lutein cysts and is associated with very high sex steroid concentrations. It is a rare condition especially in the first trimester. The case described below is believed to be the only case of hyperreactio luteinalis reported following frozen embryo transfer. This case provides an opportunity to gain further insight into the mechanism responsible for this unusual condition. The 30 year old woman demonstrated a slightly elevated LH/FSH ratio (5 and 3 mIU/ml respectively) and normal baseline androgen concentrations. Two years following oocyte retrieval she had a second frozen embryo transfer. The ovaries were normal size when the embryos were transferred and androgens were still normal. The ovaries did not begin to enlarge until 51 days from transfer. A dichorionic intrauterine pregnancy with monozygotic twins in the left gestational sac was seen. Eventually, 86 days from transfer, the ovaries enlarged to 145x103x116 mm right; and 83x95x117 mm left. Serum oestradiol was 30 078 pg/ml, beta-human chorionic gonadotrophin (HCG) 239 920 mIU/ml, serum progesterone >160 ng/ml, total testosterone 2254 ng/dl, free testosterone 42.3 pg/ml and androstenedione 7328 ng/dl. Throughout the first trimester, serum FSH was <1 mIU/ml. Thus, neither FSH nor a corpus luteum is necessary to initiate this syndrome. 相似文献
29.
An unusual localization of localized colitis cystica profunda in a 31-year-old man is described. The patient presented as anal bleeding and a protruding mass at the descending colon; the mass was polypoid and was made up of papillary epithelial hyperplasia with downward herniation of glands into the submucosa. Only one similar case involving a descending colon has been reported in the world literature. 相似文献
30.