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101.
Cytogenetic and molecular analysis of DNA sequences with highly polymorphic microsatellite markers have implicated allele loss in several chromosomal regions including 3p, 6p, 6q, 8p, 9p, 9q, 11p and 14q in the pathogenesis of sporadic renal cell carcinomas (RCCs). Deletions involving the long arm of chromosome 7 have not been described in RCCs although they have been seen in several other tumor types. However, there have been no detailed analysis of loss of heterozygosity (LOH) of 7q sequences in sporadic RCCs. We therefore studied LOH for DNA sequences on 7q with 10 highly polymorphic markers in 92 matched normal/tumor samples representing sporadic RCCs including papillary, nonpapillary, and oncocytomas in order to determine whether allelic loss could be detected in a tumor type with no visible 7q rearrangements at the cytogenetic level. We found chromosome 7q allele loss in 59 of 92 cases (64%) involving one, two, or more microsatellite markers. The most common allele loss included loci D7S522 (24%) and D7S649 (30%) at 7q31.1-31.2, a region that contains one of the common fragile sites, FRA7G. By comparative multiplex PCR analysis, we detected a homozygous deletion of one marker in the 7q 31.1-31.2 region in one tumor, RC21. These results support the idea that a tumor suppressor gene in 7q31 is involved in the pathogenesis of sporadic renal cell carcinomas.  相似文献   
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A computer model has been developed that can be used to describe the human arterial system mathematically. It simulates the complex relationship of morphology and hydraulics in the vessel network. After entering patient data into a standard vessel model, the mean flow velocity, the flow direction, and the blood pressure at each specified point of the flow network can be calculated. The vessel picture can be altered and modified with the help of a graphic editor. Localized or diffuse stenoses, bypasses with simple or multiple anastomoses, end-to-end anastomoses, end-to-side anastomoses, etc., can be studied in terms of the hydraulic effects on the local situation or on the entire vessel system. Experimental results of ultrasonic mean flow data in vessel systems of leg and cerebral arteries of patients are compared with calculated values. The predicted and measured flow velocities show a mean difference of about 10% indicating that such a computer model may be successfully used in the optimal planning of bypass operations.  相似文献   
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Three glycoforms of alpha 1-acid glycoprotein (AGP) were biotinylated to examine their binding in mouse testis by light microscopy. The transition from one stage to another in the spermatogenic cycle is marked with an appearance of a receptor for the Concanavalin A (Con A) non-reactive glycoform AGP-A in the cytoplasm of spermatocytes, young spermatids and Sertoli cells. This receptor disappears in the late stages of the spermatids. The Con-A intermediately reactive and the Con-A reactive glycoforms, AGP-B and AGP-C, showed weak reaction in the cytoplasm of spermatocytes, spermatids and Sertoli cells and, at the last stages in the spermatogenic cycle, a very strong reaction in the late elongated spermatids and the apical extensions of Sertoli cells. The interactions are lectin-like as confirmed by inhibition with simple sugars. In addition, the bindings were inhibited by steroid hormones. AGP-A was inhibited by testosterone, oestradiol and progesterone, while AGP-B and AGP-C were inhibited by mannose, GlcNAc, cortisone, aldosterone, oestradiol and progesterone. The receptors and the corresponding AGP glycoforms may be adhesion molecules between Sertoli cells and the spermatogenic cells and may have a function as a regulatory factor for spermatozoa development.  相似文献   
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OBJECTIVE: To assess the effect of oestrogen (ER) and progesterone (PgR) receptors on the prognosis of patients with operable breast cancer and the decision to treat these patients with adjuvant tamoxifen. DESIGN: Retrospective. SETTING: Eight community hospitals in the Southeast Netherlands. METHOD: Using the registry of the Comprehensive Cancer Centre South, 2862 breast cancer patients were identified with stage I, II or IIIA tumours, treated during the period 1984-1992. RESULTS: ER and PgR status were known for 2393 (84%) and 1761 (62%) patients respectively. From 1991, over 80% of the postmenopausal, lymph node positive patients had received tamoxifen, irrespective of the steroid receptor status. Of all lymph node negative patients fewer than 3% received adjuvant systemic treatment. Among the lymph node negative patients the steroid receptor status was not a significant predictor of survival. Among the lymph node positive patients whose tumours were both ER-negative and PgR-negative, a 2.8-fold increased risk of death was found during the first four years after primary treatment. The risk of death was not increased if only the ER or only the PgR status was negative. CONCLUSION: This study shows that ER and PgR receptors are significant prognostic factors for survival in breast cancer patients with involved axillary lymph nodes. The prognostic effect appeared to be restricted to the first four years after primary treatment. Selection of patients for endocrine treatment should be based on the steroid receptor status, considering the importance of the steroid receptors for predicting the response to endocrine treatment.  相似文献   
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The speaking stomach syndrome consists of persisting gurgling sounds in the gastric region, synchronous with breathing. A characteristic finding in patients suffering from this syndrome is an abnormal pattern of respiration, with extreme activity of the abdominal muscles and active involvement of the diaphragm. To teach the patient a different way of breathing using combined thoracic/abdominal respiration, with no, or hardly any, active contraction of the abdominal muscles, is an essential feature of treatment. This is accomplished in three steps. The treatment was successful in the three cases. Problems encountered in therapy are discussed.  相似文献   
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The alpha-naphthyl acetate esterase in both group I and group II thyroid cells is shown to contain SH groups since there is a decline in activity in both cell groups when certain sulfhydryl reagents [DTNB; 5,5'-Dithiobis-(2-nitrobenzoic acid)-AgNO3-Mersalyl-PCMB (parachloro mercuribenzoate) + urea] are added to the incubation media. Thus the inhibition is by far the greatest in group I cells, which also show the greatest activity after incubation in conventional media, when long fixation and storage times are used. In all cases the inhibiting effect was complete or almost completely reversed if cysteine was added to the incubation media in equivalent concentrations to the SH blocker. There were great differences among the sulfhydryl reagents used in their ability to bring about enzyme inhibition. The alkylating agents NEM (N-ethylmaleimide) and iodoacetamide had no or little effect while PCMB could only inhibit the activity of the alpha-naphthylacetate esterase if the enzyme was denaturated with 5 M urea. The maximal inhibitory effect of PCMB was only obtained when NaCl was added to the incubation media. The most effective inhibitor was AgNO3.  相似文献   
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