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81.
The monoclonal antibody (Mab) OM-1, which defines the ovarian carcinoma-associated sebaceous gland antigen (SGA), and Mab F36/22, which defines the ductal carcinoma antigen (DCA), were tested for reactivity against a synthetic peptide representing the repeat twenty amino acid sequence of the human polymorphic epithelial mucin core protein plus four amino acids of the adjacent sequence (p1-24). OM-1 bound strongly to the peptide by direct dot blot assay and ELISA and the minimum epitope for OM-1 was shown to be APDTRP(A) by inhibition assay. F36/22 reacted weakly with the peptide under the same conditions and its affinity for peptide in solution was relatively very low. Mab OC125, which defines the ovarian cancer-associated antigen CA125, did not react with the p1-24 peptide. Five other anti-mucin Mabs (HMFG1, HMFG2, BC1, BC2, BC3), previously shown to bind to the p1-24 peptide, reacted strongly with SGA by direct binding and in a sandwich assay with OM-1 as the capture Mab. F36/22 was weakly positive under the same conditions suggesting that both peptide and SGA do not express the optimal epitope for F36/22 binding. These results indicate that SGA and possibly DCA have the repeat sequence core protein of the breast carcinoma-associated human polymorphic epithelial mucin.  相似文献   
82.
Pineal germinoma: MR imaging   总被引:6,自引:0,他引:6  
Magnetic resonance (MR) imaging characteristics of pineal germinomas are described in seven patients imaged with MR and computed tomography (CT). In patients with symptoms of an enlarging process in the quadrigeminal plate cistern, MR imaging was as sensitive as CT scanning in detecting the mass. MR imaging did not detect a normal-sized, calcified neoplastic gland. Germinoma, germinoma with embryonal cell carcinoma elements, and pineoblastoma demonstrated different MR signal characteristics. Although direct coronal and sagittal MR images were useful in defining the relationship of the tumor to the posterior third ventricle, Sylvian aqueduct, and vein of Galen, the ease, rapidity, and sensitivity of CT scanning suggest that CT should remain the modality of choice for initial evaluation and screening of the pineal region, especially in the younger pediatric population, in whom detection of calcification may provide the only clue of an abnormality.  相似文献   
83.
Pulmonary histiocytosis X: comparison of radiographic and CT findings   总被引:6,自引:0,他引:6  
The authors retrospectively evaluated radiographs, computed tomographic (CT) scans, and results of pulmonary function tests (when available) for 17 patients with biopsy-proved pulmonary histiocytosis X. In 11 patients, high-resolution CT was used. In 12 patients, CT demonstrated cystic air spaces, usually less than 10 mm in diameter. In three of these 12, cysts were the only abnormality, but in six others, nodules (usually less than 5 mm in diameter) were also present. Two patients had only nodules and one, only emphysema. CT showed that many lesions that appeared reticular on plain radiographs were actually cysts. CT showed no central or peripheral concentration of lesions, but it did reveal that many small nodules were distributed in the centers of secondary lobules around small airways. CT findings correlated better with the diffusing capacity (rho = -0.71) than did the plain radiographic findings (rho = -0.57). Thus, CT was better than radiography at showing the morphology and distribution of lung abnormalities.  相似文献   
84.
The optics of eccentric photo refraction are analysed. The variation of photo refractive lunula area with refractive error, pupil size, flash eccentricity and camera aperture were calculated using a model eye. Measurements from photographs of paraxial (eccentric) photo refraction of model eyes show that a good agreement exists between theory and experiment over a range of refractive errors from — 10 D to +10 D. Calculations were also made for a standard reduced eye. The optimal set-up for measuring refractive error accurately over a wide range of refractive states is discussed, as are the problems which arise from non-central fixation.  相似文献   
85.
This is a retrospective analysis of 50 patients with carcinoma of the superior pulmonary sulcus, treated with curative intent at the University of Florida between October 1964 and October 1981. Treatment groups included preoperative radiation therapy and surgery (40 patients), radiation therapy alone (7 patients), and surgery with postoperative radiation therapy (3 patients). There was a minimum 2-year follow-up. Local control was obtained in 8 of 26 evaluable patients (31%) treated with preoperative radiation therapy and surgery, 2 of 6 patients treated with radiation therapy alone, and 0 of 2 patients treated with surgery and postoperative radiation therapy. Twelve (30%) of 40 patients receiving planned preoperative radiation therapy did not undergo definitive surgery. Absolute survival free of disease at 5 years by treatment group for patients at risk was 3 of 30 (10%) with preoperative radiation therapy and surgery, 0 of 3 with surgery and postoperative radiation therapy, and 2 of 7 with radiation therapy alone. Since one third of the patients who received low- to moderate-dose preoperative radiation therapy did not undergo definitive surgery, and since there is a small but significant survival with radiation therapy alone, it seems unwise to give moderate-dose preoperative radiation therapy, which implies an unfavorable radiation technique for the unresectable cases. The recommendation is to treat patients with lesions believed to be resectable by initial surgical resection followed by high-dose radiation therapy in selected patients with questionable margins or positive lymph nodes. Those patients with borderline or apparently unresectable lesions are recommended to be treated with radiation therapy alone.  相似文献   
86.
Summary Phallic construction/reconstruction represents one of the most challenging areas of surgery. The multiplicity of aesthetic, functional, and structural problems set this field apart from most other areas of reconstructive surgery. Described herein is a procedure for total phallic construction in a single stage. The procedure utilizes a combination of local muscle or myocutaneous flaps and free microvascular transfer flaps. The procedure results in a cosmetically acceptable phallus which has erogenous sensibility. Erectile function currently is obtained by the implantation, in a separate stage, of an erectile prosthesis.  相似文献   
87.
The breast cancer-associated epitope (mammary serum antigen or MSA) defined by monoclonal antibody (Mab) 3E1.2 is a neuraminidase-sensitive carbohydrate expressed on MUC-1-encoded molecules. However, the reactivity of Mab 3E1.2 is also reduced by protease treatment of the mucin, which suggests that 3E1.2 binds to multimers of the sialylated carbohydrate in a protein conformation-dependent manner. The common N-acetyl derivative of neuraminic acid (5-acetylneuraminic acid) is not involved in the epitope, since lectins specific for 5-acetylneuraminic acid (linked to GalNAc or Gal) are nonreactive with MSA-positive molecules. However, the N-glycolyl derivative, 5-glycolylneuraminic acid (Neu5Gc), forms a major part of the epitope since both free Neu5Gc and porcine stomach mucin (greater than 90% neuraminic acid as Neu5Gc) inhibit the binding of Mab 3E1.2, while bovine or ovine submaxillary mucins, fetuin, bovine gangliosides, and other carbohydrates do not. Indeed, the presence of Neu5Gc on human tumor mucin was confirmed by electrospray mass spectrometry. Neu5Gc is attached to an O-linked carbohydrate, since the expression of MSA by MCF-7 breast cancer cells is inhibited by the O-glycosylation inhibitor phenyl-N-acetyl-alpha-D-galactosaminide, but not by the N-glycosylation inhibitor tunicamycin, and the epitope is removed by treatment with O-glycanase but not N-glycanase F, endoglycosidase F, or endoglycosidase H, which are specific for N-linked glycans. This is likely to be a core glycan since 3E1.2 reacts after treatment of the mucin with trifluoromethanesulfonic acid, which removes most backbone and peripheral carbohydrates. Treatment with galactosidase or N-acetyl glucosaminidase enhances the binding of Mab 3E1.2, indicating that the Neu5Gc is not attached to galactose or N-acetyl galactosamine. Furthermore, the susceptibility of MSA to treatment with Arthrobacter urea-faciens neuraminidase [which is specific for alpha (2-6)-linked NeuNAc] and the loss in reactivity of GalNAc-specific lectins after periodate oxidation [alpha (2-3)-linked but not alpha (2-6)-linked NeuNAc protects GalNAc from periodate oxidation] indicate that the Neu5Gc may be attached alpha (2-6) to peptide-linked GalNAc. These results show that MSA is a Neu5Gc-containing O-linked core glycan, which represents a unique tumor-associated epitope not previously identified on human mucins.  相似文献   
88.
This study was carried out to evaluate the metabolic consequences of osteosclerotic skeletal metastases of prostatic origin in a homogeneous group of patients. We found significantly increased mean values of serum alkaline phosphatase activity and significantly reduced mean values of serum phosphate, 24-h urinary calcium, fasting calcium excretion and TmP/GFR in cancer patients with respect to age-matched controls. Mean serum immunoreactive parathyroid hormone (iPTH) levels were raised, with two patients showing increased values of the hormone above our normal limits. Our findings indicate that mild secondary hyperparathyroidism is a feature of these patients. However, it cannot be excluded that both the reduced serum phosphate and TmP/GFR values may be related, at least in some cases, to the effects of the tumour itself on tubular reabsorption of phosphate.  相似文献   
89.
Conjoined twins, right atrial isomerism, and sequential segmental analysis.   总被引:1,自引:0,他引:1  
Three cases of twins conjoined across the chest were examined. In one set, one twin showed right atrial isomerism and the other showed the usual atrial arrangement. The other two sets showed the usual atrial arrangement in both twins. The associated cardiac anomalies were diverse, ranging from atrioventricular septal defects to absent atrioventricular connections. Sequential segmental analysis was used successfully in each case to classify the complex cardiac anomalies. The first step was the recognition of the atrial arrangement. This was easily achieved despite the complexity of the intracardiac morphology.  相似文献   
90.
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