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91.
We present six cases which illustrate the spectrum of clinical features, macroscopic findings and light microscopic findings of urine extravasation from the upper urinary tract. The early lesions are characterized macroscopically by an oedematous, glistening or gelatinous appearance to the renal perihilar and peripelvic fat. Light microscopically there is lipolysis with associated foamy macrophages, multinucleate giant cells and lymphocytes. Immunohistochemical staining for Tamm–Horsfall protein is strongly positive in the extracellular space and in the foamy macrophages confirming urine extravazation. Later lesions are characterized by cicatrization of fibrous tissue around the renal pelvis and hydronephrosis. Microscopically there is relatively bland fibrosis with occasional lymphocytes and histiocytic cells. The late lesions are also characterized by extracellular deposits of weakly eosinophilic, granular or hyaline material, the so called 'urinary precipitates'. These deposits stain strongly with diastase PAS and weakly positive for Tamm–Horsfall protein. The staining of these urinary precipitates is analogous to renal tubular hyaline casts, thus supporting the theory that they are derived from uroproteins. We consider that these deposits are pathognomic of past urine extravasation.  相似文献   
92.
Children with mild to moderate renal insufficiency may be at an increased risk for developing glomerulosclerosis and subsequent renal failure. Low protein diets (LPD) have been shown to delay the progression of renal insufficiency in laboratory animals and may be of benefit in adult humans. The nutritional costs of a LPD in adults are reportedly minimal. We review the protein and caloric requirements of growing children and discuss the potential harmful effects and benefits of an LPD in this population. We also discuss dietary adherence and the difficulty of designing an LPD for children. We conclude that the protein content of a typical American diet can safely be reduced to, but not below, the recommended daily allowance for protein if diets are carefully planned, patients and their parents extensively counseled, and if dietary supplements are given to help meet the caloric and vitamin-mineral nutrient needs of growing children. In addition, ongoing nutritional assessment, counseling, and frequent monitoring of growth, diet and biochemical indicators of protein status are essential for maintaining the health of these children.  相似文献   
93.
OBJECTIVE: Our purpose was to investigate immunosuppressive acidic protein in the prognostic characterization of advanced ovarian cancer. STUDY DESIGN: Serum levels of immunosuppressive protein were prospectively measured in 80 patients with untreated ovarian carcinoma. To evaluate the prognostic significance of immunosuppressive acidic protein levels, cutoff points were studied every 50 μg/ml between 450 and 1350 μg/ml. RESULTS: Pretreatment immunosuppressive acidic protein levels were not significantly associated with stage, histotype, grade of differentiation, postoperative residual tumor, and response to chemotherapy. The most significant association with survival was observed at a cutoff value of 1100 μg/ml (p = 0.0089). In the univariate analysis for overall survival, International Federation of Gynecology and Obstetrics stage and immunosuppressive acidic protein status were found to have a role in predicting ovarian cancer prognosis. In the multivariate analysis only immunosuppressive acidic protein status was significantly associated with survival. A statistical correlation was found between serum levels and overall survival (p = 0.0104, χ2 6.56), including immunosuppressive acidic protein as a continuous variable. CONCLUSION: Our data suggest that immunosuppressive acidic protein assay is a potentially useful tool in the prognostic characterization of advanced ovarian cancer. (Am J Obstet Gynecol 1996;175:1606-10.)  相似文献   
94.
95.
The detergent-soluble extract of rat ovary plasma membranes contained a Gs protein of about 100 kDa as shown by its elution behavior on a Bio Gel A-1.5m column. However, the cell membranes exposed to hCG (37° C, 15 min) contained in addition a higher molecular weight Gs protein complex of 300 kDa comprised of human chorionic gonadotropin (hCG) receptor (hCGR) and Gs. The complex bound with an affinity column of GTP-Sepharose and could be released with Gpp(NH)p and GTP inhibited this binding. The presence of the hCGR in the complex was shown by its binding to 125I-hCG. Furthermore, GTP inhibited the binding of hCG to the complex. These results indicate the presence of hCGR and Gs protein complex in the hCG-treated membranes. hCGR and Gs protein were individually purified and reconstituted into phospholipid vesicles. The protein-phospholipid vesicles showed saturation kinetics of binding of 125I-hCG and 3H-Gpp(NH)p. Incubation of phospholipid vesicles with hCG resulted in a 2–3-fold increase in the binding of 3H-Gpp(NH)p and GTPase activity. Activation of Gs protein was dependent on the length of incubation and the hormone concentration. Deglycosylated hCG was about 10 times less potent than hCG suggesting a role of carbohydrates of hCG in inducing hCG-Gs protein interactions. The data with the in vitro reconstitution system rule out the involvement of a carbohydrate-binding lectin in the function of the hormone.  相似文献   
96.
Keratinocyte intercellular adhesion molecule (ICAM)-I expression is induced by interferon (IFN)-gamma. It has been previously reported that IFN-beta suppresses IFN-gamma-induced ICAM-I expression in A431 cells, a human squamous cell carcinoma cell line. In this study, the suppression mechanisms were investigated at the post second messenger level. Both 12-O-tetradecanoylphorbol-13-acetate (TPA) and calcium ionophore (A23187) induce ICAM-I expression in A431 cells. ICAM-I expression induced by either was not suppressed with cotreatment with IFN-beta. Furthermore, IFN-beta did not inhibit the translocation of protein kinase C (PKC) by TPA. It appears that the pathways involved in ICAM-I expression induced by activation of PKC or increased in intracellular Ca++ are not affected by IFN-beta.  相似文献   
97.
行为实验己经证明,锌过多或缺锌均可影响脑功能。锌作为体内重要的微量元素,影响多种酶的活性及蛋白质和核酸的台成。本实验通过体外分离大鼠脑海马突触体,观察不同浓度锌离子对Ca2 -Mg2 ATP酶的活性和3H-Leu掺入突触蛋白合成的影响.结果表明:1.锌离子浓度在25μmol/L时增加该酶的活性(<0.01),并促进3H-Leur掺入蛋白质的合成(<0.05)。2.锌离子在50,100,200μmol/L的较高浓度时对Co2 -M2 ATP酶的活性有显著的抑制作用(分别为:P<0.05.P<0.01,P<0.01),仅200μmol/L对3H—Leu掺入突触蛋白合成有抑制作用。本研究提示:适量的锌对突触体功能的维持是必要的,但剂量过高则起相反作用。  相似文献   
98.
99.
Decorin, a collagen-binding small proteoglycan, is considered to have a specific function in the organization or stability of the collagen network. Therefore, alteration of its molecular properties may be of pathophysiological relevance during the development of cartilage damage. It is shown here that normal cartilage from rabbit knee-joint contains glycosaminoglycan chain-bearing core protein fragments of 39, 23, and 18 kDa, each one amounting to approximately 5-6% of the intact decorin core protein. Continuous infusion of human recombinant interleukin-1 alpha for 14 days (200 ng/day) into a knee-joint led in condylar cartilage to a reduction in the amount of intact core protein from 2 micrograms/mg wet tissue to about 1.1 micrograms/mg. The increase in its quantity found after infusion of heat-inactivated interleukin-1 was not statistically significant. The concentration of all three core protein fragments became reduced to a similar extent as the intact core protein under the influence of the cytokine, and additional fragments were not found. Surprisingly, there was a much smaller response to interleukin-1-treatment in patellar cartilage.  相似文献   
100.
The anucleate (distal) segment of a crayfish medial giant axon (MGA) remains intact for months in vivo after severing the axon from its cell body, a phenomenon referred to as long-term survival (LTS). We collected axoplasm from chronic anucleate MGAs by perfusing 2-cm lengths of axons with an intracellular saline. This axoperfusate was analyzed by SDS-PAGE and silver stained. Axoperfusate proteins from intact MGAs and from chronic anucleate MGAs exhibiting LTS for up to 6 months were the same. Furthermore, immunoreactive levels of actin and β-tubulin were similar in axoperfusates from intact and chronic anucleate MGAs. This maintenance of proteins in chronic anucleate MGAs must be due to a lack of protein degradation and/or to local protein synthesis by a source other than the cell body. To investigate local protein synthesis in vitro, we added [35S]-methionine to the extracellular saline surrounding intact and chronic anucleate MGAs. After 4- to 6-h incubations, radiolabelled proteins were detected in axoperfusates analyzed by SDS-PAGE and fluorography. The similarity between radiolabelled proteins in axoperfusates and MGA glial sheaths indicated a glial origin for the radiolabelled axoperfusate proteins. Various observations and control experiments suggested that glial-axonal protein transfer occurred by a physiological process. Glial-axonal protein transfer may contribute to the maintenance of proteins during LTS of chronic anucleate MGAs.  相似文献   
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