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81.
82.
BACKGROUND: Mature teratoma is often found in resected retroperitoneal residual tumor masses (RRTM) after chemotherapy for disseminated nonseminomatous testicular germ cell tumors (NSTGCT). The aim of this report is to describe the clinical course of patients after resection of residual teratoma, with particular emphasis on relapse with either growing mature teratoma or secondary non-germ cell malignancy. METHODS: During the period 1979-1995, 113 patients underwent a laparotomy for resection of RRTM after chemotherapy for NSTGCT. Only patients with mature teratoma in the RRTM were included in the current study, and data on the patients who experienced relapse were studied in detail. RESULTS: Mature teratoma was found in 51 patients (45.1%) with RRTM resected after chemotherapy. Nine of these 51 patients (17.6%) relapsed; the relapses resulted from growing mature teratoma in 5 patients (9.8%), secondary non-germ cell malignancy in 3 patients (5.9%), and recurrent germ cell malignancy in 1 patient (2.0%). The primary treatment for all relapsing patients was surgical excision. All five patients with growing mature teratoma are alive without evidence of disease, as is the patient with recurrent germ cell malignancy. One of the three patients with non-germ cell malignancy died of disease, and the remaining two are alive with disease. CONCLUSIONS: Long term follow-up after resection of postchemotherapy residual teratoma is indicated because a proportion of patients develop growing mature teratoma or a secondary non-germ cell malignancy. The treatment for these recurrences should be complete surgical excision.  相似文献   
83.
The wrist is a common site of injury in sports, both acute and chronic. Evaluation of wrist injuries requires knowledge of anatomy kinematics, attention to the mechanism of injury, the intensity of training, and a focus on the physical examination for specific injuries.  相似文献   
84.
PURPOSE: We evaluated the feasibility of 18 Fluoride Positron Emission Tomography (18F-PET), investigated the characteristics appearance of bony structures, and compared the quality of 18F-PET images with conventional bone scans (BS). METHOD: 18F-PET scans were performed in 59 patients additional to conventional bone scintigraphy. RESULTS: Even very small details in the spine like the spinous and transverse processes were clearly visible with 18F-PET. Only half of these structures were visualised with BS. When visualising the vertebral bodies of the first rib from the clavicles and the twelfth rib from the kidneys, we arrived at similar results. Hot spots in the skull or at the manubriosternal joint were observed in 29% of the patients without any evidence of trauma, degeneration or metastasis. CONCLUSION: 18F-PET shows more details of the skeleton compared to BS. Some hot spots not occurring with BS must be regarded as physiological.  相似文献   
85.
We proposed the endogenous thrombin potential (ETP) as an overall function test of the coagulation system. We recently introduced a routine test which requires defibrinated plasma. In order to develop an assay in which the ETP-value can be directly obtained by measuring the optical density, we investigated two methods to inhibit fibrinogen clottability and to inactivate alpha2-macroglobulin. The first method makes use of hydroxylamine to inactivate alpha2-macroglobulin and H-Gly-Pro-Arg-Pro-OH to inhibit fibrin polymerization. At pH 7.35, plasma incubated with 25 mM hydroxylamine and 1.5 mg/mL H-Gly-Pro-Arg-Pro-OH for 5 minutes at 37 degrees C resulted in a reduced endlevel of the amidolytic activity on small chromogenic substrates. The second method uses a metalloprotease purified from Crotalus basiliscus to remove alpha2-macroglobulin from plasma in combination with H-Gly-Pro-Arg-Pro-OH. Herein plasma is incubated with 3.5 LM protease during 15 minutes at 37 degrees C in the presence of 1 mg/mL polymerization inhibitor. The enzymatic method results in a zero endlevel of the amidolytic activity and this would imply that measurement of the ETP is reduced to an endpoint determination of the optical density. We show that the endpoint determination of the optical density correlates well with the calculated ETP in plasmas with different degrees of anticoagulation.  相似文献   
86.
Vascular endothelial growth factor (VEGF) is a potent and selective vascular endothelial cell mitogen and angiogenic factor. VEGF expression is elevated in a wide variety of solid tumors and is thought to support their growth by enhancing tumor neovascularization. To block VEGF-dependent angiogenesis, tumor cells were transfected with cDNA encoding the native soluble FLT-1 (sFLT-1) truncated VEGF receptor which can function both by sequestering VEGF and, in a dominant negative fashion, by forming inactive heterodimers with membrane-spanning VEGF receptors. Transient transfection of HT-1080 human fibrosarcoma cells with a gene encoding sFLT-1 significantly inhibited their implantation and growth in the lungs of nude mice following i.v. injection and their growth as nodules from cells injected s.c. High sFLT-1 expressing stably transfected HT-1080 clones grew even slower as s.c. tumors. Finally, survival was significantly prolonged in mice injected intracranially with human glioblastoma cells stably transfected with the sflt-1 gene. The ability of sFLT-1 protein to inhibit tumor growth is presumably attributable to its paracrine inhibition of tumor angiogenesis in vivo, since it did not affect tumor cell mitogenesis in vitro. These results not only support VEGF receptors as antiangiogenic targets but also demonstrate that sflt-1 gene therapy might be a feasible approach for inhibiting tumor angiogenesis and growth.  相似文献   
87.
The contribution of BRCA1 and BRCA2 to inherited breast cancer was assessed by linkage and mutation analysis in 237 families, each with at least four cases of breast cancer, collected by the Breast Cancer Linkage Consortium. Families were included without regard to the occurrence of ovarian or other cancers. Overall, disease was linked to BRCA1 in an estimated 52% of families, to BRCA2 in 32% of families, and to neither gene in 16% (95% confidence interval [CI] 6%-28%), suggesting other predisposition genes. The majority (81%) of the breast-ovarian cancer families were due to BRCA1, with most others (14%) due to BRCA2. Conversely, the majority of families with male and female breast cancer were due to BRCA2 (76%). The largest proportion (67%) of families due to other genes was found in families with four or five cases of female breast cancer only. These estimates were not substantially affected either by changing the assumed penetrance model for BRCA1 or by including or excluding BRCA1 mutation data. Among those families with disease due to BRCA1 that were tested by one of the standard screening methods, mutations were detected in the coding sequence or splice sites in an estimated 63% (95% CI 51%-77%). The estimated sensitivity was identical for direct sequencing and other techniques. The penetrance of BRCA2 was estimated by maximizing the LOD score in BRCA2-mutation families, over all possible penetrance functions. The estimated cumulative risk of breast cancer reached 28% (95% CI 9%-44%) by age 50 years and 84% (95% CI 43%-95%) by age 70 years. The corresponding ovarian cancer risks were 0.4% (95% CI 0%-1%) by age 50 years and 27% (95% CI 0%-47%) by age 70 years. The lifetime risk of breast cancer appears similar to the risk in BRCA1 carriers, but there was some suggestion of a lower risk in BRCA2 carriers <50 years of age.  相似文献   
88.
PURPOSE: Decreased local immunity to uropathogenic bacteria may be a factor predisposing women to recurrent urinary tract infections. Our phase I study demonstrated the safety of a multi-strain vaccine administered as a vaginal suppository. A phase II study was conducted to determine vaccine efficacy. MATERIALS AND METHODS: A total of 91 women susceptible to recurrent urinary tract infections was entered into the study and the courses were analyzed in a randomized, double-blind, placebo controlled trial of vaginal mucosal immunization. Subjects received 3 vaginal suppositories at weekly intervals. Depending on the treatment group each suppository contained 1 of 2 vaccine doses or suppository material only. Each patient was followed for 5 months to record infection episodes, and obtain urine, vaginal irrigates and serum to measure immunological responses. RESULTS: Immunogen treated women who were off antibiotic prophylaxis throughout the study had a significant delay in interval to reinfection during the first 8 weeks compared to women receiving placebo. Mean interval until reinfection was delayed from 8.7 weeks for placebo treated to 13 weeks for vaccine treated women. Immunological responses in serum, urine and vaginal fluid were variable. No serious adverse effects were observed. CONCLUSIONS: These data demonstrate that vaginal mucosal immunization can enhance resistance to urinary tract infections in susceptible patients.  相似文献   
89.
90.
Extracellular calcium/polyvalent cation-sensing receptors (CaR) couple to G proteins and contain highly conserved extracellular cysteine residues. Immunoblotting of proteins from rat kidney inner medullary collecting duct endosomes with CaR-specific antibodies reveals alterations in the apparent molecular mass of CaR depending on protein denaturation conditions. When denatured by SDS under nonreducing conditions, CaR migrates as a putative dimeric species of 240-310 kDa. This is twice the predicted molecular mass of the CaR monomer observed after SDS denaturation in the presence of sulfhydryl-reducing agents. In sucrose density gradients, Triton X-100-solubilized CaR sediments as a 220-kDa complex, not explainable by binding of G proteins to CaR monomers. Treatment of Triton-soluble CaR with divalent (Ca2+, Mg2+) and trivalent (Gd3+) metal ion CaR agonists, but not monovalent ions (Na+), partially shifts the electrophoretic mobility of CaR under reducing conditions from a predominantly monomeric to this putative dimeric species on immunoblots in a manner similar to their rank order of functional potency for CaR activation (Gd3+ > Ca2+ > Mg2+). This Ca2+ effect is blocked by pretreatment with N-ethylmaleimide. We conclude that disulfide bonds present in CaRs mediate formation of dimers that are preserved in Triton X-100 solution. In addition, CaR exposure to Ca2+ induces formation of additional disulfide bonds within the Triton-soluble CaR complex.  相似文献   
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