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81.
Resection of the adrenal glands precludes participation in many immunotherapy protocols for metastatic renal cell carcinoma. We performed radical nephrectomy with adrenalectomy and contralateral partial adrenalectomy, including adrenal vein ligation for a 4 cm. hilar metastasis without perioperative complications or local recurrence after 30 months. Adrenal function, measured by cosyntropin stimulation tests 6 weeks and 10 months postoperatively, was normal. Partial adrenalectomy with preservation of adrenal function is possible.  相似文献   
82.
CAM 4515 and CAM 4750 are new nonpeptide tachykinin NK1 receptor antagonists with different lipophilicities. Two separate, simple, and sensitive HPLC methods for the quantitation of these two compounds in plasma and the evaluation of their oral bioavailability in rats were developed and validated. Extraction of CAM 4515 from plasma involved protein precipitation with acetonitrile, while that for CAM 4750 involved a one-step liquid-liquid extraction with methylene chloride. The analytes in extracts were chromatographed on a C18 column using two different separation buffers, 47% 0.02 M sodium citrate (pH 3.5)-53% acetonitrile for CAM 4515 and 59% 0.02 M potassium phosphate dibasic (pH 7.0)-41% acetonitrile for CAM 4750, and both compounds were detected by fluorescence (excitation 278 nm; emission 342 nm). Stability profiles of both drugs at −20°C or room temperature in plasma and in reconstituted buffers were good. The limit of quantitation for both drugs was 5 ng ml−1 with good linearity from 5 to 1000 ng ml−1 using 100–200 μl of plasma. Excellent precision (relative standard deviation < 8.3%) and accuracy (relative error ± 9.2%) were observed for both CAM 4515 and CAM 4750. Oral bioavailability studies were conducted for each compound in rats receiving a p.o. dose of 20 mg kg−1 and an i.v. dose of 5 mg kg−1. The absolute oral bioavailability of CAM 4750 (80%) was estimated to be 40-fold greater than that of CAM 4515 (2%). The experimental results suggest that incorporation of a pyridine group into the structural backbone may greatly improve bioavailability.  相似文献   
83.
We report on 7 patients (6 M, 1 F) with Coffin-Lowry syndrome who have a sensorineural hearing deficit in addition to developmental delay and characteristic facial changes. One of the patients also had a history of premature exfoliation of primary teeth. These are previously unappreciated clinical signs that may aid in the early diagnosis of Coffin-Lowry syndrome. Early diagnosis and recognition of a hearing deficit in the patient can lead to the use of hearing aids to help the patient achieve his or her full potential. These “;new”; clinical manifestations expand the phenotype of Coffin-Lowry syndrome and constitute an additional indication of pleiotropy. © 1993 Wiley-Liss, Inc.  相似文献   
84.
Roth  J; Burwinkel  F; van den Bos  C; Goebeler  M; Vollmer  E; Sorg  C 《Blood》1993,82(6):1875-1883
MRP8 and MRP14 are two Ca(2+)-binding proteins of the S-100 family expressed by myelomonocytic cells. Both proteins assemble to noncovalently associated complexes in a Ca(2+)-dependent manner. Members of the S-100 family are known to play a role in cytoskeletal- membrane interactions; therefore, we investigated the subcellular distribution of MRP8/MRP14 and their complexes in human monocytes. Using differential centrifugation and subsequent Western blot or enzyme- linked immunosorbent assay analysis, we found that MRP8/MRP14 were almost completely translocated from the cytoplasma to membrane and cytoskeletal structures in a Ca(2+)-dependent manner. Using a cross- linking technique, complexed forms of MRP8/MRP14 were found to be associated with the plasma membrane. Analysis of MRP-transfected L132 cells showed that the MRP8 as well as the MRP14 component of the MRP8/MRP14 complex may independently bind to membrane and cytoskeletal structures. Furthermore, immunogold electron microscopy showed a colocalization of MRP8/MRP14 and the intermediate filament type III protein vimentin in A23187-treated monocytes. Our data indicate that, in analogy to other S-100-like proteins, MRP8 and MRP14 play a role in Ca(2+)-dependent cytoskeletal-membrane interactions. Restriction of MRP8/MRP14 expression to distinct stages of myelomonocytic differentiation suggests that these proteins are involved in highly specific pathways of intracellular signaling in phagocytes.  相似文献   
85.
Although some behavioral effects of cocaine are hypothesized to be due to blockade of dopamine uptake in nucleus accumbens, it has been reported that in nucleus accumbens there are no specific cocaine binding sites and that cocaine is a weak inhibitor of dopamine uptake. [3H]GBR 12935 and an unlabelled analog, GBR 12909, are ligands that bind with great affinity and specificity to a site on dopamine uptake complex in striatum. We therefore investigated the interaction of these GBR compounds with the dopamine uptake complex in nucleus accumbens. We found specific high affinity [3H]GBR 12935 binding and a significant correlation between displacement of [3H]GBR 12935 binding by a series of compounds in striatum and nucleus accumbens. GBR 12909 inhibited dopamine uptake with equal potency in nucleus accumbens and striatum. Thus, there appear to be some aspects of the dopamine uptake complex in nucleus accumbens and striatum that are similar.  相似文献   
86.
Objectives.To test the safety, efficacy, and toxicity of gene therapy using wild-type p53-expressing adenovirus (Ad-CMV-p53) in a nude mouse model with intraperitoneal (ip) 2774 human ovarian cancer cell line that contains a p53 mutation.Study design.An initial study of adenovirus tolerance was determined in nude mice by a single ip injection of increasing doses of Ad-CMV-p53. Nude mice were implanted with an LD100dose of 1 × 107cells. To study the efficacy and specificity of Ad-CMV-p53 treatment, the mice received treatment with different adenovirus constructs. One group received Ad-CMV-p53 and another group received a control adenovirus construct, Ad-CMV-βgal. To study the treatment response to Ad-CMV-p53, the mice were divided into groups and received various treatment schedules of 1 × 108pfu of Ad-CMV-p53.Results.The mice tolerated Ad-CMV-p53 without adverse effects at doses of 1 × 108pfu. The response to Ad-CMV-p53 showed significant survival duration in each dose regimen, with a survival time greater than that of untreated animals (P= 0.0173). However, no statistically significant survival advantage was observed between Ad-CMV-p53- and Ad-CMV-βgal-treated mice.Conclusions.These studies show that at the adenovirus dose and administration regimen used, there is effective but not specific 2774 tumor growth inhibitionin vivo.Efficient introduction of biologically active genes into tumor cells would greatly facilitate cancer therapy. Thus, although promising, these results caution that much effort will be required to realize the potential for clinical application of adenovirus-based ovarian cancer gene therapy.  相似文献   
87.
88.
Venous disease: investigation and treatment,fact or fiction?   总被引:1,自引:1,他引:0       下载免费PDF全文
This review looks at some clinical and experimental methods and treatments used in venous disease, and attempts to dispel some myths which have been associated with it. Over the last century numerous techniques have been introduced to aid the understanding of the physiology of normal legs and the pathophysiology of those with venous disease. Tourniquet testing along with clinical examination remains the only method of venous assessment in most hospitals. Venous ulceration in the past has been associated with deep vein incompetence, but the newer, non-invasive techniques of Doppler ultrasound and duplex examination are now identifying patients with leg ulceration who have superficial venous insufficiency and therefore a surgically correctable condition. Perforating veins and their possible role in the aetiology of venous ulceration along with invasive and non-invasive methods for their detection is reviewed. Some of the conservative compression treatments and dressings available for the treatment of venous ulceration are discussed. It is concluded that adherence to sound surgical principles remains the mainstay of the successful management of patients with venous disease.  相似文献   
89.
90.
Regulation of T cell-dependent immune responses is mediated in part by bone marrow-derived antigen presenting cells (APC) that (a) process and present antigens which engage the T cell receptor and (b) secrete cytokines that influence the threshold of T cell activation. The anterior chamber of the eye is lined by the corneal endothelium (which rests on a stroma and epithelium that is devoid of class II MHC + APC) and iris/ciliary body (which contain significant numbers of bone marrow-derived cells, one third of which are class II MHC +). When tested in vitro, these potential APCs fail to present antigens in a form that activates T cells. Moreover, iris/ciliary body cells actually suppress activation of T cells exposed to antigens on conventional APC. In addition, aqueous humor under normal circumstances contains factors (one of which is TGFB) that are potent inhibitors of antigen-driven T cell activation, but spare other aspects of T cell function. Evidence suggests that the bone marrow-derived cells in iris/ciliary body are the source of this factor. Thus, the anterior chamber contains powerful forces that can prevent induction and can suppress expression of T cell mediated immunity. It is proposed that these forces are responsible for immunologic privilege and anterior chamber associated immune deviation, and for suppressing pathologic proliferation and inflammation in the anterior segment of the eye.  相似文献   
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