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71.
The rib is an uncommon site of osteosarcoma. With the use of adjuvant chemotherapy and aggressive surgical resection of the metastatic pulmonary lesions, extrapulmonary metastases are becoming more clinically evident. Primary rib osteosarcoma with extrapulmonary metastasis is exceedingly rare. A case is reported, showing that the pattern of metastasis of rib osteosarcoma is similar to that of primary bone osteosarcoma. The liver metastasis occurred after resection of the metastatic pulmonary lesions. A CT scan of the primary rib lesion and liver metastasis both showed a lace‐like enhancement pattern, its histological appearance corresponding with neoplastic osteoid. With the increasing use of CT abdomen for localization of extrapulmonary metastases, lace‐like enhancement may be seen more readily in the future.  相似文献   
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The impact of a professionally facilitated peer group intervention for HIV prevention among 400 low-income Chilean women was examined using a quasiexperimental design. At 3 months postintervention, the intervention group had higher HIV-related knowledge, more positive attitudes toward people living with HIV, fewer perceived condom use barriers, greater self- efficacy, higher HIV reduction behavioral intentions, more communication with partners about safer sex, and decreased depression symptoms. They did not, however, have increased condom use or self-esteem. More attention to gender barriers is needed. This intervention offers a model for reducing HIV for women in Chile and other Latin American countries.  相似文献   
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Pelvic actinomycosis associated with intrauterine devices   总被引:1,自引:0,他引:1  
O'Connor  KF; Bagg  MN; Croley  MR; Schabel  SI 《Radiology》1989,170(2):559-560
The authors describe two women with pelvic pain, long-term use of an intrauterine device, and a pelvic mass due to Actinomyces israelii. The diagnostic imaging findings were nonspecific but included mass effect and mucosal irregularity of the rectosigmoid colon at barium enema examination and complex masses and inflammatory changes at computed tomography and magnetic resonance imaging. Radiologists should be aware of the imaging findings of this potentially lethal but curable condition.  相似文献   
77.
Unilateral vestibular hypofunction (UVH) is a common vestibular dysfunction. Its influence upon the vestibulospinal reflex (VSR) is studied by posturography. The postural sway is disturbed when the VSR is disregulated because of the UVH. The degree of disturbance depends on the effectivity of the central compensation. Our results indicate that these adaptive mechanisms become less effective with advancing age. The importance of ocular fixation as a compensatory mechanism is also obvious. The comparison between posturographic recordings made with eyes open and those made with eyes closed, shows that, in elderly people, more abnormal posturographic recordings are found with eyes closed. Accordingly, with regard to the problem of falling in the elderly, the function of the vestibular system must be assessed and especially its influence upon the standing posture. The combination of classical vestibular and posturographic results affords this indispensable information.  相似文献   
78.
Mangan  KF; D'Alessandro  L 《Blood》1985,66(3):533-541
To define further the role of marrow T suppressor lymphocytes in the pathogenesis of the hypoproliferative anemia in all Rai clinical stages of B cell chronic lymphocytic leukemia (CLL), marrow erythroid progenitor cell (CFU-E and BFU-E) frequency, marrow T gamma lymphocyte frequency per 1,000 nucleated marrow cells, and T cell-erythroid progenitor cell interactions were examined in 30 CLL patients and normal control subjects. As compared with control subjects, decreased numbers of CFU-E and BFU-E were found in patient marrow depleted of neoplastic B cells in all Rai stages of the disease. As a group, Rai stage III through IV patients with or without aplasia (CLL-aplasia) had significantly fewer CFU-E and BFU-E than did Rai O through II stage patients. The numbers of T gamma cells infiltrating CLL marrows were increased 3, 9, and 20 times normal in Rai O through II, Rai III through IV, and CLL-aplasia groups, respectively. Removal of T cells from marrow increased growth of CFU-E and BFU-E in all Rai O through IV patients, but the increase was significant in the CLL-aplasia group only (P less than .05). However, autologous coculture of marrow T cells or T gamma cells but not B cells with marrow B + T-depleted null cells at ratios of 0.2:1 to 1:1 suppressed CFU-E and BFU-E growth in all three patient groups. We conclude that the hypoproliferative anemia occurring in the course of B cell CLL is due to gradual accumulation in the marrow of T gamma lymphocytes which suppress erythroid progenitor cell growth. T gamma cell suppression of erythropoiesis and marrow T gamma cell expansion is detectable in the earliest Rai stages of the disease.  相似文献   
79.
Unger  EC; Gado  MH; Fulling  KF; Littlefield  JL 《Radiology》1987,162(3):789-795
Magnetic resonance (MR) imaging was performed in five monkeys with experimentally induced acute cerebral infarction to define the MR imaging features and correlate these with computed tomographic (CT) findings, laboratory analysis, and histopathologic studies. Acute infarct (2-4 hours after embolization) was generally visible on MR images but not on CT scans. CT at 24 and 48 hours did show the infarcts. In all cases the infarct was more clearly depicted with MR imaging and was visualized as an area of high signal intensity on T2-weighted images. Spectrometric nuclear MR measurements of the postmortem cerebral tissue confirmed prolongation of both T1 and T2 values similar to that calculated from MR images. At postmortem laboratory testing, the area of infarction detected with MR imaging had decreased specific gravity and increased water content, reflecting edema.  相似文献   
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