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排序方式: 共有794条查询结果,搜索用时 15 毫秒
1.
2.
Intratemporal vascular tumors: detection with CT and MR imaging 总被引:1,自引:0,他引:1
Lo WW; Shelton C; Waluch V; Solti-Bohman LG; Carberry JN; Brackmann DE; Wade CT 《Radiology》1989,171(2):445-448
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion. 相似文献
3.
Linus Okeke Odunayo Ikuerowo Ifeanyi Chiekwe Blessing Etukakpan Olayiwola Shittu Olubunmi Olapade-Olaopa 《International journal of urology》2007,14(8):729-732
OBJECTIVE: Varicocele is the most common treatable cause of male infertility and is associated with progressive decline in testicular function. Varicocelectomy, a commonly performed operation, is indicated in infertile males with varicoceles who have oligospermia, asthenospermia, teratospermia or a combination of these factors. It is not clear if varicocelectomy is indicated if the patients have normal sperm density associated with asthenospermia or teratospermia. METHODS: We reviewed 167 patients with varicocele-associated male infertility over a 7-year period (December 1999-November 2005). Pre- and post-varicocelectomy seminal fluid analyses, assessed using the World Health Organization criteria, were obtained at intervals of 4-6 months. Wilcoxon signed rank tests were used to evaluate for statistical significance and P < or = 0.05 was considered significant. RESULTS: The mean age of the patients and their spouses were 35 and 28 years, respectively. The mean duration of infertility was 3.2 years (range, 1.5-7.5). Oligospermia, teratospermia, asthenospermia, oligospermia, asthenospermia and teratospermia (OAT) syndrome and azoospermia were found preoperatively in 106 (63.5%), 58 (34.7%), 154 (92%), 118 (71%) and 15 (9%) patients, respectively. Overall, significant improvements in semen volume (P < 0.001), sperm density (P < 0.001), sperm motility (P < 0.001) and sperm vitality (P < 0.001) were obtained after varicocelectomy. There was, however, no significant improvement in sperm morphology after varicocelectomy (P = 0.220). When patients with preoperative oligospermia (sperm density, <20 million/mL) were considered separately, varicocelectomy led to significant improvement in all the semen parameters except the sperm morphology (P = 0.183). Conversely, when varicocele patients with a sperm density of > or =20 million/mL (normospermia) associated with asthenospermia and/or teratospermia were considered separately, they did not show significant improvement in any of the semen parameters after varicocelectomy (P > 0.05). In addition, azoospermic patients did not show significant improvement in any of the semen parameters (P > 0.05) CONCLUSION: No significant improvement in semen parameters may be obtained in patients with clinical varicocele and preoperative normospermia. It is possible that only patients with preoperative oligospermia may benefit from varicocelectomy. Larger multi-institutional studies are needed to determine more definitively if asthenospermia or teratospermia in normospermic subfertile males with clinical varicoceles are in fact indications for varicocelectomy. 相似文献
4.
S. Spellerberg P. Reimer G. Blessing H.H. Coenen S.M. Qaim 《Applied radiation and isotopes》1998,49(12):611
55Co and 57Co were produced via (p, α) and (p, 2p) reactions, respectively, on highly enriched 58Ni. Thin deposits of 58Ni on Cu backing, obtained electrolytically, were irradiated using a slanting beam. The separation of radiocobalt and the recovery of the enriched target material were effected via anion-exchange chromatography. 相似文献
5.
6.
WW Thompson 《Transfusion》1993,33(4):333-335
This study was designed to determine the blood donation behavior and attitudes of Hispanic residents of the Lower Rio Grande Valley for the purpose of developing promotional and educational approaches to enhance levels of donor participation. Personal interviews of 545 respondents were conducted in English and Spanish using quota sampling and standard intercept techniques at lower- and middle-income supermarkets in five cities during a payday weekend. A number of research hypotheses were established to test for demographic, behavioral, and attitudinal differences that were observed in donors and nondonors using chi-square analysis and multiple discriminant analysis. After analyzing the difference between Hispanics and non-Hispanics for blood donation rates, all non-Hispanics were eliminated from analysis, and the remaining 419 Hispanics were evaluated on the basis of their donor behavior. Donation among Hispanics was most likely to be by better- educated, English-speaking, higher-job-status individuals who had participated in a blood donation drive. Donors tend to have parent(s) who were donors, and they were also more likely to carry an organ donor card. Donors were found to vary in their behaviors as well as their attitudes and beliefs. Perceptions of a lack of safety in donating, the risk of contracting acquired immune deficiency syndrome, and the financial motivation of donors were most pronounced among Hispanics, which indicated a need for improved education on these issues. 相似文献
7.
H B Muss J A Blessing P Hanjani J H Malfetano G M Kemp K Webster 《American journal of clinical oncology》1992,15(4):363-364
Eighteen evaluable patients with recurrent or metastatic nonsquamous carcinoma of the uterine cervix were treated with 1,500 micrograms/m2 of echinomycin every 4 weeks. Seven patients had received prior chemotherapy. There was one complete response (5.6%), 95% confidence interval for response of 0-27%. The major toxicity was nausea and vomiting, which was moderate to severe in eight patients. Myelosuppression was minimal. Echinomycin in this dose and schedule displays minimal activity in patients with advanced nonsquamous carcinoma of the cervix. 相似文献
8.
Dr Jonas Hähnel MD Wolfgang Friesdorf MD Bernhard Schwilk MD Thomas Marx MD Silvia Blessing 《Journal of clinical monitoring and computing》1992,8(1):1-6
The technical equipment of today's intensive care unit (ICU) workstation has been characterized by a gradual, incremental accumulation of individual devices, whose presence is dictated by patient needs. These devices usually present differently designed controls, operate under different alarm philosophies, and cannot communicate with each other. By contrast, ICU workstations could be equipped permanently and in a standardized manner with electronically linked modules if the attending physicians could reliably predict, at the time of admission, the patient's equipment needs. Over a period of 3 1/2 months, the doctors working in our 20-bed surgical ICU made 1,000 predictions concerning outcome, equipment need, duration of artificial ventilation, and duration of hospitalization for 300 recently admitted patients. The interviews were made within the first 24 hours after admission. The doctors being interviewed were usually (i.e., in over 90% of cases) unfamiliar with the patient. Information concerning the patient's general state of health, special pre-ICU events, and complications was offered to the interviewed clinician because this information represents standard admission data. It was found that the equipment need (represented by two different setups, high tech and low tech) could be predicted most reliably (96.4% correct predictions) compared with a prediction on outcome of ICU treatment (94.5%), on duration of artificial ventilation (75.4%), and on duration of stay (43.4%). There was no significant (p>0.05) difference in the reliability of predictions between residents and consultants. Factors influencing the postoperative equipment need varied with surgical specialty. The general state of health, as indicated by the ASA classification (p<0.001), and the specific intervention (all multiple-valve replacements needed the high-level equipment standard) appeared to be most important in cardiac surgery, while a state of septicemia was important in general surgery (p<0.001). Our findings suggest that ICU workstations may be standardized into at least two types. 相似文献
9.
Schramm C Huber S Protschka M Czochra P Burg J Schmitt E Lohse AW Galle PR Blessing M 《International immunology》2004,16(9):1241-1249
10.
Tumor Vascularity Is Not a Prognostic Factor for Malignant Melanoma of the Skin 总被引:1,自引:4,他引:1
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Klaus J. Busam Marianne Berwick Karen Blessing Katrin Fandrey Sewon Kang Themis Karaoli Judy Fine Alistair J. Cochran Wain L. White Jason Rivers David E. Elder Duan-Ren Po Wen Bradley H. Heyman Raymond L. Barnhill 《The American journal of pathology》1995,147(4):1049-1056
Tumor vascularity has been proposed as a prognostic indicator for a number of solid tumors. Although a correlation between microvessel number and metastatic behavior has also been suggested for cutaneous melanoma, the small number of cases studied to date allows one to draw only preliminary conclusions. In this study, we have assessed tumor vascularity in cutaneous melanoma by comparing 60 cases of metastasizing and non-metastasizing tumors matched for tumor thickness, age, sex, and anatomic site. Ulex europaeus agglutinin I appeared to be the most suitable vascular marker for this study. Our results indicate that there was no statistically significant difference between the two groups with regard to tumor vascularity. Even after identifying 15 cases of thin (<1.0 mm thick) melanoma, there was no significant difference in the number of microvessels between metastasizing and non-metastasizing tumors. Comparison of patterns of vascular microarchitecture also failed to discriminate between the two groups. Thus, our results indicate that tumor vascularity may not be an independent prognostic factor for cutaneous melanoma. 相似文献