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11.
Isolated tuberculosis of the coccyx is extremely rare. A 35-year-old man presented with a 3-month history of coccygeal and gluteal pain. Computed tomography and magnetic resonance imaging revealed osseous destruction and a large enhancing mass involving the coccyx with anterior and posterior extension. Pathologic examination of the surgical specimen revealed necrosis, chronic granulomatous inflammation, and multinucleated giant cells consistent with tuberculosis. This case highlights the importance of considering tuberculosis as a diagnosis even though unusual sites are involved.  相似文献   
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Background  

Early sexual maturation has been associated with overweight that may persist after the completion of biological growth and development. We have prospectively examined the influence of early sexual maturation on subsequent overweight in late adolescence and assessed if this association was modified by central adiposity in early adolescence.  相似文献   
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Background: Preoperative staging is essential for planning of optimal therapy for patients with rectal cancer. Recently, magnetic resonance imaging (MRI) is used frequently because of its benefits of clear pelvic image are better than other diagnostic methods. The purpose of this study was to determine accuracy rates and clinical usefulness of MRI in preoperative staging of rectal cancer.Methods: Between February, 1997, and December, 1999, 217 patients with histologically proven rectal cancer were staged preoperatively and had surgical resections performed. MRI criteria for depth of invasion was determined by the degree of disruption of the rectal wall. Metastatic perirectal lymph nodes were considered to be present if they showed heterogenous texture, irregular margin, and enlargement (.10 mm).Results: The accuracy of the MRI for determining depth of invasion was 176/217 (81%) and regional lymph node invasion was 110/217 (63%). In the T stage, accuracy rate of T1 was 3/4 (75%), T2 was 20/37 (54%), T3 was 141/162 (87%), and T4 was 12/14 (86%), respectively. The specificity of lymph node invasion was 45/110 (41%) and the sensitivity was 91/107 (85%). The accuracy rate of regional lymph node involvement was 136/217 (63%). T1 and T2 were overstaged in 1/4 (25%) and 17/37 (46%), respectively, and T3 was understaged in 15/162 (9.2%). The accuracy rate to detect metastatic lateral pelvic lymph node was 4/14 (29%) after lateral pelvic lymph node dissection was done in 14 patients under MRI. The accuracy rate in assessing levator ani muscle tumor involvement was 8/11 (72%).Conclusions: MRI showed a good, comparable accuracy rate for determining depth of tumor invasion, compared with transrectal ultrasonography, which still has a low accuracy rate for detecting metastatic lymph node. MRI with endorectal coil may increase the accuracy rate of T1 and T2 lesions. In addition, clear sagittal and coronal sectional pelvic images can give a lot of information about adjacent organ invasion or any invasion of levator ani muscle. MRI can be useful for choosing an appropriate extent of lymph node dissection and type of surgery.  相似文献   
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While female mice do not have the equivalent of a menopause, they do undergo reproductive senescence. Thus, to dissociate the effects of aging versus estrogen deficiency on age‐related bone loss, we sham‐operated, ovariectomized, or ovariectomized and estrogen‐replaced female C57/BL6 mice at 6 months of age and followed them to age 18 to 22 months. Lumbar spines and femurs were excised for analysis, and bone marrow hematopoietic lineage negative (lin–) cells (enriched for osteoprogenitor cells) were isolated for gene expression studies. Six‐month‐old intact control mice were euthanized to define baseline parameters. Compared with young mice, aged/sham‐operated mice had a 42% reduction in lumbar spine bone volume/total volume (BV/TV), and maintaining constant estrogen levels over life in ovariectomized/estrogen‐treated mice did not prevent age‐related trabecular bone loss at this site. By contrast, lifelong estrogen treatment of ovariectomized mice completely prevented the age‐related reduction in cortical volumetric bone mineral density (vBMD) and thickness at the tibial diaphysis present in the aged/sham‐operated mice. As compared with cells from young mice, lin– cells from aged/sham‐operated mice expressed significantly higher mRNA levels for osteoblast differentiation and proliferation marker genes. These data thus demonstrate that, in mice, age‐related loss of cortical bone in the appendicular skeleton, but not loss of trabecular bone in the spine, can be prevented by maintaining constant estrogen levels over life. The observed increase in osteoblastic differentiation and proliferation marker gene expression in progenitor bone marrow cells from aged versus young mice may represent a compensatory mechanism in response to ongoing bone loss. © 2010 American Society for Bone and Mineral Research.  相似文献   
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Rats were fed, for 3 days, four synthetic diets, all of which contained the same proportion of carbohydrate (50 per cent) and were of equal caloric value per gram. These diets contained either 0 or 15 per cent fat. The fats used were lard, corn oil, Wesson oil, and a hydrogenated vegetable oil. The feeding of the fat-containing diet for 3 days increased the liver's capacity for incorporating acetate carbon to cholesterol. The fats tested were of about equal value in stimulating hepatic cholesterogenesis. The various diets fed had no effect on the lipide or glycogen content of the liver nor on the lipide content of plasma.  相似文献   
18.
Inhibin production by the corpus luteum was investigated by undertaking pharmacological rescue of the corpus luteum with hCG in four healthy women. Blood samples were collected daily for two menstrual cycles. Starting 7 days after the LH surge in the second cycle, incremental doses of hCG (125-8000 IU) were administered daily for 7 days resulting in hCG levels comparable to those seen in normal pregnancy. Following hCG, the luteal phase was prolonged and there were significant increases in the plasma concentrations of inhibin (P less than 0.05), and oestradiol (P less than 0.05). The progesterone concentration was maintained at the mid-luteal phase peak and as a result was significantly higher than those on the equivalent days of the control cycle (P less than 0.05). It was concluded that rescue of the corpus luteum with physiological levels of hCG resulted in a significant output of inhibin, thus suggesting that the corpus luteum is a significant source of inhibin in early pregnancy.  相似文献   
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Oocyte retrieval in a stimulated in-vitro fertilization treatment cycle was unsuccessful when inadvertently carried out 12 h after the administration of human chorionic gonadotrophin (HCG) injection. Repeat follicular aspiration at 36 h post-HCG injection recovered 20 oocytes, out of which 16 metaphase-II eggs were subjected to intracytoplasmic sperm injection and eight became fertilized. Uterine transfer of three cleaving embryos resulted in a singleton pregnancy which went to term and a healthy female infant was delivered. Our experience shows that in addition to issues of HCG bioavailability to the developing follicles, the temporal relationship between HCG administration (or the luteinizing hormone surge) and follicular aspiration is also an important consideration in the determination of the aetiology of the empty follicle syndrome.   相似文献   
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