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排序方式: 共有1036条查询结果,搜索用时 15 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results   总被引:2,自引:0,他引:2  
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2.
Nineteen patients with ovarian cancer and minimal residual or persistent disease who were treated with cisplatin or carboplatin-based intraperitoneal (IP) regimens had distribution studies of IP contrast and computerized tomography prior to and during treatment. The distribution pattern was assessed retrospectively and scored for the presence of contrast in each of eight regions: the under surface of right and left diaphragms, the right and left paracolic gutters, the lesser omental sac, the intramesenteric region and the true and false pelvis. Assigning a point to each region with adequate distribution, we classified 10 patients to an excellent pattern (greater than or equal to 7 of 8 regions), 6 to a good pattern (5 to less than 7 regions), and 3 to an inadequate distribution pattern (less than 5 regions). Serial studies were performed in 8 patients after more than 4 cycles of IP therapy. In these patients, all of whom were tolerating treatment without progression, the distribution remained virtually unchanged for those with excellent distribution. One of three with good distribution manifested inadequate distribution on repeat study, and one of two with inadequate distribution improved to show a good pattern. In this small study there was no correlation of distribution patterns with plasma CA-125 at onset of IP treatment and prior surgical procedures or placement of the catheter tip. However, three patients with unsatisfactory patterns had procedures consisting of catheter placement only rather than formal reassessment laparotomies for ovarian cancer. Since satisfactory IP distribution may be required for obtaining a therapeutic advantage from IP therapy, methods for its assessment must be developed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
Elevated levels of acute phase plasma proteins in major depression.   总被引:10,自引:0,他引:10  
Levels of acute phase and other plasma proteins were measured in 21 men with major depression, 28 men with alcohol dependence, and 12 men who acted as controls. The depressed men had significantly elevated levels of the acute phase proteins, haptoglobin and alpha-1-antichymotrypsin, and of immunoglobulin G. The elevations in haptoglobin and alpha-1-antichymotrypsin were highly correlated with each other, and were correlated with the severity of depression and negatively correlated with the thyroid stimulating hormone response to thyrotropin. The alcoholic men had elevated haptoglobin levels, but significantly decreased levels of immunoglobulin G. These findings provide further evidence for an inflammatory response during depression.  相似文献   
4.
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.  相似文献   
5.
Screening for early ovarian cancer   总被引:5,自引:0,他引:5  
Taylor  KJ; Schwartz  PE 《Radiology》1994,192(1):1
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6.
MR imaging of neurocysticercosis   总被引:1,自引:0,他引:1  
Magnetic resonance (MR) was performed in 50 patients with neurocysticercosis. Comparison was made with other neuroradiological imaging modalities including CT, myelography, CT ventriculography, and CT myelocisternography. Eighteen patients were found to have intraventricular cysts. In several patients, these were multiple and 22 intraventricular cysts were discovered. Although 4 of the 22 ventricular cysts were missed by MR, T1-weighted images can play a significant role in the early detection of intraventricular cysticercosis cysts, showing the cyst wall (9 of 22), a high intensity mural nodule (6 of 22), and increased signal intensity of the cyst fluid (5 of 22). Cisternal cysts (14 cysts in 10 patients) could be identified; they appear similar to intraventricular cysts, but mural nodules are infrequently seen (1 of 14). Twenty-nine patients had 69 parenchymal cysts. An attempt was made to assess the viability of these parenchymal lesions by matching the CT and MR findings with the Escobar pathologic staging system. Neuroimaging findings seemed compatible with early parenchymal lesions in the vesicular stage in 11 instances. Findings in cases with later stage cysts tend to support the concept that a dying larva provokes pronounced inflammatory reaction in the adjacent brain. Computed tomography remains the superior modality for depicting parenchymal calcifications within dead larvae. A case of a spinal cysticercosis cyst demonstrated with MR (in a patient with extensive intracranial cisternal cysts and a fourth ventricular cyst) is described.  相似文献   
7.
8.
A 17-year-old male presented to a local hospital with symptoms of pneumonia and a hacking cough productive of yellow sputum. Direct examination of a bronchial lavage sample revealed organisms morphologically consistent with Blastomyces dermatitidis, which was confirmed by culture. The patient was placed on intravenous antifungal therapy and his condition improved dramatically. OBJECTIVES: to describe the gross and microscopic morphologies of both yeast and mold forms of B. dermatitidis; to identify B. dermatitidis given patient history, and microscopic and colony morphology; to describe the symptoms of primary pulmonary infections caused by B. dermatitidis, and to name additional tissues typically affected by the systemic pathogen.  相似文献   
9.
Tumor vascular signals in renal masses: detection with Doppler US   总被引:3,自引:0,他引:3  
Ramos  IM; Taylor  KJ; Kier  R; Burns  PN; Snower  DP; Carter  D 《Radiology》1988,168(3):633-637
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   
10.
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   
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