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61.
On the botanical distribution of chiral forms of gossypol 总被引:1,自引:0,他引:1
Plants belonging to Malvaceae (about 90 species belonging to 33 genera) were analysed for the presence of gossypol by reversed-phase HPLC using absorbance detection at 365 nm, and the chirality and optical purity of gossypol were determined whenever the analysis was positive. Only plants belonging to the cotton tribe (Gossypieae) contained gossypol (detection limit better than 0.001%). In particular, no gossypol could be detected in ABELMOSCHUS ESCULENTUS (ocra), HIBISCUS TILIACEUS, H. SABDARIFFA, and HEREA BRASI-LIENSIS, earlier claimed to contain this compound. Gossypol-containing plants usually produced dextrorotatory gossypol of varying optical purity; an enantiomeric excess of (-)-gossypol was detected in only one plant, GOSSYPIUTN BARBADENSE. 相似文献
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Is there increased intervertebral mobility in isthmic adult spondylolisthesis? A matched comparative study using roentgen stereophotogrammetry 总被引:4,自引:0,他引:4
STUDY DESIGN: By roentgen stereophotogrammetric technique, the intervertebral mobility of the spondylolytic segment in eight patients was measured and compared with the mobility of eight nonspondylolytic patients matched according to sex, afflicted segment, and grade of disc degeneration. OBJECTIVES: To compare the intervertebral mobility of a spondylolytic segment with the mobility of a segment without spondylolysis in adult patients with back pain. SUMMARY OF BACKGROUND DATA: Evidenced by the resulting olisthetic deformity and supported by the outcome from prior investigations, spondylolysis is assumed to induce spinal segmental instability/hypermobility. METHODS: After percutaneous application of tantalum indicators for roentgen stereophotogrammetric technique, the intervertebral translations of the spondylolytic fifth lumbar vertebra were measured in eight adult patients with low back pain and low-grade olisthesis. Eight other patients without spondylolysis but with low back pain presumably on degenerative basis were chosen for comparison and had an identical measuring procedure using roentgen stereophotogrammetric technique. The two groups were matched in pairs according to sex, afflicted segment, and grade of disc degeneration. RESULTS: No significant difference was registered considering the intervertebral mobility for matched pairs in the two groups neither along the sagittal nor the vertical axis. The transverse translations were mostly negligible in both groups. CONCLUSION: The spondylolytic defect in pars interarticularis does not cause permanent instability/hypermobility detectable in the adult patient with low back pain and low-grade olisthesis. 相似文献
64.
Tumor recurrence and survival in patients treated for thymomas and thymic squamous cell carcinomas: a retrospective analysis. 总被引:14,自引:0,他引:14
Philipp Str?bel Andrea Bauer Bernhard Puppe Til Kraushaar Axel Krein Klaus Toyka Ralf Gold Michael Semik Reinhard Kiefer Wilfred Nix Berthold Schalke Hans Konrad Müller-Hermelink Alexander Marx 《Journal of clinical oncology》2004,22(8):1501-1509
PURPOSE: Thymic epithelial tumors (TET) are rare epithelial neoplasms of the thymus with considerable histologic heterogeneity. This retrospective study focused on the correlation of WHO-defined TET histotypes with survival and tumor recurrence in a large cohort of patients receiving different modes of treatment. PATIENTS AND METHODS: Two hundred twenty-eight patients were followed for up to 21 years (median, 60 months; range, 1 to 252 months) after primary surgery. Forty-two patients received adjuvant radiotherapy (mean dose, 53 Gy), and 33 patients received adjuvant chemotherapy. RESULTS: Seventy-six (88%) of 86 patients with WHO type A, AB, and B1 thymomas were treated by surgery alone, with three tumor relapses after 3 to 10 years (median, 3.4 years). Twelve of 67 patients with WHO type B2 and B3 thymomas in Masaoka stages I and II were treated by adjuvant radiotherapy without evidence of tumor recurrence after 1 to 12 years (median, 4 years). Among 75 patients with B2 and B3 thymomas with incomplete resection or a tumor stage III or higher, the recurrence rate was 34% (n = 23) after 0.5 to 17 years (median, 5 years) in patients receiving adjuvant radiochemotherapy, compared to 78% (seven of nine patients) in patients without adjuvant radiochemotherapy. Incomplete tumor resection was associated with a high recurrence rate (65%) and a poor prognosis (P <.01). CONCLUSION: The long-term outcome of TET patients is related to tumor stage, WHO histotype, completeness of surgical removal, and type of treatment. Prospective trials are warranted to formally address the efficacy of adjuvant therapy in the treatment of localized and advanced malignant TETs. 相似文献
65.
Fredrik Wiklund Bj?rn-Anders Jonsson Anthony J Brookes Linda Str?mqvist Jan Adolfsson Monica Emanuelsson Hans-Olov Adami Katarina Augustsson-B?lter Henrik Gr?nberg 《Clinical cancer research》2004,10(21):7150-7156
PURPOSE: The RNASEL gene has been proposed as a candidate gene for the HPC1 locus through a positional cloning and candidate gene approach. Cosegregation between the truncating mutation E265X and disease in a hereditary prostate cancer (HPC) family and association between prostate cancer risk and the common missense variant R462Q has been reported. To additionally evaluate the possible role of RNASEL in susceptibility to prostate cancer risk, we performed a comprehensive genetic analysis of sequence variants in RNASEL in the Swedish population. EXPERIMENTAL DESIGN: Using 1624 prostate cancer cases and 801 unaffected controls, the truncating mutation E265X and five common sequence variants, including the two missense mutations R462Q and D541E, were evaluated for association between genotypes/haplotypes and prostate cancer risk. RESULTS: The prevalence of E265X carriers among unaffected controls and prostate cancer patients was almost identical (1.9 and 1.8% in controls and cases, respectively), and evidence for segregation of E265X with disease was not observed within any HPC family. Overall, the analyses of common sequence variants provided limited evidence for association with prostate cancer risk. We found a marginally significant inverse association between the missense mutation D541E and sporadic prostate cancer risk (odds ratio, 0.77; 95% confidence interval, 0.59-1.00) and reduced risk of prostate cancer in carriers of two different haplotypes being completely discordant. CONCLUSIONS: Considering the high quality in genotyping and the size of this study, these results provide solid evidence against a major role of RNASEL in prostate cancer etiology in Sweden. 相似文献
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Except in emergencies, the medical treatment of incompetent patients also has to be based upon an informed consent between the physician and a legitimate legal representative (durable power of attorney). Consequently, the German 'Betreuungsrecht' advices persons to designate in advance such a proxy or surrogate. However, an additional court-decision is demanded, if a medical measure poses significant risks for the future health or the life of the incompetent patient. On the base of the available epidemiologic data we illustrate that neither our medical nor our legal system could realistically cope with the practical consequences of this legislation: The vast majority of our present decisions in such cases is not covered by a legally valid informed consent, which implies possible forensic consequences. This article provides relevant clinical and legal advice on how to protect the legitimate interests of all concerned within the present framework, which should urgently be revised. 相似文献
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We have reported a rare case of a giant ovarian tumor which, due to the lack of proper health care on the side of the patient, had not been diagnosed until 27 weeks of pregnancy. The patient did not demonstrate any clinical symptoms till the moment of the diagnosis. Peripheral blood analysis showed severe anemia at the admission. The right adnex with the multilocular cystic tumor containing bloody fluid and measuring 40 cm in diameter, was removed in the course of the surgical procedure. The histological diagnosis of the tumor was: serous cyst. Surgical removal of the giant tumor allowed for further development of pregnancy and enabled vaginal delivery of healthy newborn at term. 相似文献
70.