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21.
Heterozygotes for cystinuria   总被引:3,自引:0,他引:3  
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BACKGROUND: Squamous cell carcinoma (SCC) is the second most common type of skin cancer in the United States. Cutaneous SCC has the potential to metastasize and cause morbidity and mortality. OBJECTIVE: Our purpose was to review and summarize the literature on metastatic cutaneous SCC, including risk factors for metastasis, data from clinical studies, and current management. RESULTS: Multiple studies confirm that even well-differentiated and small tumors (<2 cm) may metastasize. Over the past two decades, additional literature on the risk factors for metastatic cutaneous SCC, including immunosuppression, has been published. In addition, new staging systems have been proposed that may influence management of these tumors. Chemotherapy regimens are numerous, but remain limited in ability to improve overall survival. CONCLUSION: Although we know more about the risk factors, survival for patients with metastatic cutaneous SCC depends on extent of nodal involvement. Therefore, emphasis should remain on prevention and aggressive treatment of cutaneous SCC and vigilant observation for signs and symptoms of metastasis.  相似文献   
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Skin biopsies from nine patients with a histological and/or clinical diagnosis of cutaneous lymphocytoma, lymphoplasia or Jessner's lymphocytic infiltrate were examined by immunoenzymatic labelling with a panel of monoclonal antibodies against lymphocytes and accessory cells. Similar cellular constituents were demonstrated in the biopsies from three patients with lymphocytoma, two with lymphoplasia and two with atypical lymphocytes, but a protracted benign clinical course. The infiltrates from these patients consisted of T cells, Langerhans cells, related HLA-DR positive dendritic dermal cells and clusters of polyclonal B cells. In four patients, the B cell clusters contained B cell accessory follicular dendritic cells, and thereby closely resembled the B cell follicles seen in lymphoid organs. The T cells were predominantly T helper/inducer cells and in all patients the T cells expressed HLA-DR. One patient diagnosed as lymphocytoma cutis differed from the other patients by having no detectable B cells. One patient with Jessner's lymphocytic infiltrate differed from the other patients by having a marked relative predominance of T suppressor/cytotoxic cells. These data suggest that cutaneous lymphocytoma and lymphoplasia are basically similar disorders which may be considered to be exaggerated immune responses, whereas Jessner's lymphocytic infiltrate may be a separate entity. Immunological analysis may assist in establishing a definite diagnosis in cases of lymphocytoma or lymphoplasia with atypical cytological features.  相似文献   
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The kinetics of the enzymes hexokinase, glucose-6-phosphate dehydrogenase, and malate dehydrogenase have been determined and compared in pooled isolated sweat glands from normal and atopic subjects. No significant differences could be detected in the kinetic constants Vmax and Km for any of the substrates or co-factors studied in the two groups of subjects. The results of these experiments are discussed in relation to the current concepts regarding atopy and atopic dermatitis.  相似文献   
29.

Purpose

Instability of prostate specific antigen (PSA) in serum might complicate the interpretation of the free-to-total PSA ratio. We studied the in vitro stability of free PSA and total PSA in serum of patients with prostate cancer or benign prostate hyperplasia (BPH), and of elderly man without known prostate disease. Furthermore, we investigated conditions to stabilize the in vitro values in serum.

Materials and Methods

The effects of storage at 4C on free and total PSA were investigated in serum of 32 men with prostate cancer, 25 with BPH and 29 older than 70 years. All had total PSA less than 25 micro g./l. The influence of total PSA levels on in vitro changes in free-total PSA was studied in serum of 39 other prostate cancer patients (total PSA 1.7 to 298 micro g./l.). Stabilization studies were performed in yet another series of samples from 54 prostate cancer patients (total PSA 1.3 to 238 micro g./l.) by adjustment of serum pH to 5.5 before storage. Free and total PSA was measured by a commercial immunofluorometric assay, as well as by in-house immunofluorometric assays. Statistical analyses of the results were performed by analysis of variance with repeated measures.

Results

We found no difference between the results obtained by the 2 assay systems. After 7 days at 4C there was a slight decrease in total PSA in sera of prostate cancer patients, BPH patients and men older than 70 years. A decrease in mean free PSA values occurred in all groups (21.3, 15.7 and 14.6%, respectively). The decrease of free PSA with time was significant (p <0.0001) in all groups but there was no significant difference among the groups (p = 0.16). The concomitant decrease in free-to-total PSA ratio was significant in all groups (p <0.0001). This change was group dependent (p = 0.003), with the largest decrease in the prostate cancer group. Large interindividual differences were observed. Storage at 4C for 7 days of sera of 39 patients with localized and disseminated prostate cancer (total PSA 1.7 to 298 micro g./l.) gave a more pronounced decrease in free PSA than in total PSA. Adjustment of serum pH to 5.5 had a stabilizing effect on free PSA and on the free-to-total PSA ratio, giving a significantly smaller change in both values (p <0.0001).

Conclusions

In vitro instability of free PSA in serum and large interindividual differences should be considered when using the ratio of free-to-total PSA in evaluation of patients with suspected prostate cancer. Serum samples should be stored frozen if not analyzed immediately or acidified to pH 5.5. Interpretation of data from determination of free-to-total PSA ratio should be done with caution if the sampling and storage conditions are not known.  相似文献   
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Aim The primary aim of this investigation was to examine genotype and clinical phenotype differences in individuals with juvenile neuronal ceroid lipofuscinosis (JNCL) who were homozygous for a common disease‐causing deletion or compound heterozygous. The secondary aim was to cross‐validate the Child Behavior Checklist (CBCL) and the Unified Batten Disease Rating Scale (UBDRS), a disease‐specific JNCL rating scale. Method Sixty individuals (28 males, 32 females; mean age 15y 1mo, SD 4y 9mo, range 5y 8mo–31y 1mo) with JNCL completed the UBDRS. Results No significant genotype and clinical phenotype differences were identified when comparing individuals homozygous for the deletion with a heterogeneous group of compound heterozygous individuals. There were significant correlations among related behaviour items and scales on the CBCL and UBDRS (Spearman’s rho ranging from 0.39 [p<0.05] to 0.72 [p<0.01]). Behaviour and physical function ratings were uncorrelated, supporting divergent validity of these two constructs in JNCL. Interpretation Previous reports of genotype and clinical phenotype differences were unsupported in this investigation, which did not find differences between individuals homozygous or heterozygous for the CLN3 deletion. The CBCL, an already validated measure of behaviour problems, appears valid for use in JNCL and cross‐validates well with the UBDRS.  相似文献   
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