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排序方式: 共有827条查询结果,搜索用时 31 毫秒
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JL Abbruzzese MC Abbruzzese R Lenzi KR Hess MN Raber 《Canadian Metallurgical Quarterly》1995,13(8):2094-2103
PURPOSE: Diagnostic strategies designed to identify the underlying primary malignancies in patients with unknown primary tumors (UPTs) have relied on retrospective analyses. We analyzed 879 consecutive patients referred with suspected UPTs to determine the yield and cost of a limited diagnostic evaluation, assess the contribution of specific studies to diagnosis, and analyze the survival patterns of patients in whom the primary tumor was diagnosed. PATIENTS AND METHODS: Data from patients with a suspected UPT were entered into a computerized data base, and the patients underwent a predefined limited diagnostic evaluation. Primary malignancies were diagnosed by pathologic review alone or by pathologic criteria plus a physical or radiographic finding. Survival was measured from diagnosis, estimated using the Kaplan-Meier method, and compared using the Cox-Mantel log-rank test. RESULTS: A primary tumor was found in 179 of 879 patients (20%). The survival duration of patients in whom the primary tumor was diagnosed was superior to that of patients in whom the primary tumor remained unknown. Specific patient subsets contributed most to the improved survival duration of the group in which the primary tumor was found, including lymphoma patients diagnosed solely by pathologic criteria and female patients with primary breast or ovarian cancer. The cost of diagnosis was mostly due to the extensive use of computed tomography. Except for ovarian cancer, computed tomography rarely identified treatable primary tumors. CONCLUSION: The limited diagnostic evaluation used in this study identified patients with treatable malignancies and increased the survival duration of a population of suspected UPT patients. Primary malignancies with the best survival can be diagnosed through careful pathologic review and focused evaluations for breast and ovarian cancer in women. 相似文献
84.
Enhancing immune responses using suicidal DNA vaccines 总被引:1,自引:0,他引:1
P Berglund C Smerdou MN Fleeton I Tubulekas P Liljestr?m 《Canadian Metallurgical Quarterly》1998,16(6):562-565
We describe a DNA vaccine strategy that allows antigens to be produced in vivo in the context of an alphaviral replicon. Mice immunized with such vectors developed humoral and cellular immune responses at higher levels than mice that received a conventional DNA vaccine vector. Immunized animals acquired protective immunity to lethal influenza challenge. Compared with traditional DNA vaccine strategies in which vectors are persistent and the expression constitutive, the expression mediated by the alphaviral vector was transient and lytic. As a result, biosafety risks such as chromosomal integration, and the induction of immunological tolerance, could be circumvented. 相似文献
85.
VA Convertino LE Armstrong EF Coyle GW Mack MN Sawka LC Senay WM Sherman 《Canadian Metallurgical Quarterly》1996,28(1):i-vii
It is the position of the American College of Sports Medicine that adequate fluid replacement helps maintain hydration and, therefore, promotes the health, safety, and optimal physical performance of individuals participating in regular physical activity. This position statement is based on a comprehensive review and interpretation of scientific literature concerning the influence of fluid replacement on exercise performance and the risk of thermal injury associated with dehydration and hyperthermia. Based on available evidence, the American College of Sports Medicine makes the following general recommendations on the amount and composition of fluid that should be ingested in preparation for, during, and after exercise or athletic competition: 1) It is recommended that individuals consume a nutritionally balanced diet and drink adequate fluids during the 24-hr period before an event, especially during the period that includes the meal prior to exercise, to promote proper hydration before exercise or competition. 2) It is recommended that individuals drink about 500 ml (about 17 ounces) of fluid about 2 h before exercise to promote adequate hydration and allow time for excretion of excess ingested water. 3) During exercise, athletes should start drinking early and at regular intervals in an attempt to consume fluids at a rate sufficient to replace all the water lost through sweating (i.e., body weight loss), or consume the maximal amount that can be tolerated. 4) It is recommended that ingested fluids be cooler than ambient temperature [between 15 degrees and 22 degrees C (59 degrees and 72 degrees F])] and flavored to enhance palatability and promote fluid replacement. Fluids should be readily available and served in containers that allow adequate volumes to be ingested with ease and with minimal interruption of exercise. 5) Addition of proper amounts of carbohydrates and/or electrolytes to a fluid replacement solution is recommended for exercise events of duration greater than 1 h since it does not significantly impair water delivery to the body and may enhance performance. During exercise lasting less than 1 h, there is little evidence of physiological or physical performance differences between consuming a carbohydrate-electrolyte drink and plain water. 6) During intense exercise lasting longer than 1 h, it is recommended that carbohydrates be ingested at a rate of 30-60 g.h(-1) to maintain oxidation of carbohydrates and delay fatigue. This rate of carbohydrate intake can be achieved without compromising fluid delivery by drinking 600-1200 ml.h(-1) of solutions containing 4%-8% carbohydrates (g.100 ml(-1)). The carbohydrates can be sugars (glucose or sucrose) or starch (e.g., maltodextrin). 7) Inclusion of sodium (0.5-0.7 g.1(-1) of water) in the rehydration solution ingested during exercise lasting longer than 1 h is recommended since it may be advantageous in enhancing palatability, promoting fluid retention, and possibly preventing hyponatremia in certain individuals who drink excessive quantities of fluid. There is little physiological basis for the presence of sodium in n oral rehydration solution for enhancing intestinal water absorption as long as sodium is sufficiently available from the previous meal. 相似文献
86.
RD Rosenberg WC Hunt MR Williamson FD Gilliland PW Wiest CA Kelsey CR Key MN Linver 《Canadian Metallurgical Quarterly》1998,209(2):511-518
PURPOSE: To examine how common patient factors affect screening mammographic sensitivity and cancer stage at diagnosis. MATERIALS AND METHODS: The authors used a population-based database of 183,134 screening mammograms and a statewide tumor registry to identify 807 breast cancers detected at screening mammography. RESULTS: Sensitivity varied significantly with ethnicity, use of estrogen replacement therapy, mammographic breast density, and age. Sensitivity was 54% (13 of 24) in women younger than 40 years, 77% (121 of 157) in women aged 40-49 years, 78% (224 of 286) in women aged 50-64 years, and 81% (277 of 340) in women older than 64 years. Sensitivity was 68% (162 of 237) for dense breasts and 85% (302 of 356) for nondense breasts and 74% (180 of 244) in estrogen replacement therapy users and 81% (417 of 513) in nonusers. Sensitivity was most markedly reduced with the combination of dense breasts and estrogen replacement therapy use; there was little difference when only one factor was present. Median cancer size and the percentage of early cancers showed little change with any factors. CONCLUSION: Age is a minor determinant of mammographic sensitivity in women aged 40 years or older. Sensitivity is substantially decreased with the combination of higher breast density and estrogen replacement therapy use. There was not a notable shift in cancer outcomes in the groups with lower mammographic sensitivity. These data do not support different screening recommendations in women aged 40-49 years or in estrogen replacement therapy users. 相似文献
87.
MN Hochmeister B Budowle JW Schumm CJ Sprecher UV Borer R Dirnhofer 《Canadian Metallurgical Quarterly》1995,107(5):246-249
Allele and genotype frequencies for 3 tetrameric short tandem repeat loci were determined in a Swiss population sample (n = 100) using the GenePrint STR Multiplex System, electrophoresis of the PCR products in DNA sequencing gels and subsequent detection of allelic fragments by silver staining. The loci are HUMTH01, TPOX, and CSF1PO. The observed heterozygosities are 83.0%, 60.0%, and 72.0%, respectively. The discrimination power determined for the individual loci is 0.914, 0.780, and 0.860, respectively, and the combined discrimination power for the triplex is 0.997. All loci meet Hardy-Weinberg expectations and after Bonferroni correction there was no evidence that the population sample deviates from expectations of independence. Moreover, independence of alleles at these STR loci with other PCR-based loci derived from the same Swiss population sample, previously reported, were considered. These loci were DQA1, LDLR, GYPA, HBGG, D7S8, GC and D1S80. Again, after Bonferroni correction there was no evidence that the population sample deviates from expectations of independence among alleles at the 10 different PCR-based loci. Thus, the allelic frequency data can be used in human identity testing to estimate the frequency of a multiple PCR-based DNA profile in the Swiss population. 相似文献
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P Demailly MN Jeanteur-Lunel M Berkani M Ecoffet J Kopel G Kretz P Lavat 《Canadian Metallurgical Quarterly》1996,19(11):659-666
PURPOSE: To evaluate the middle term tonometric results of a new filtering procedure, the non penetrating deep sclerectomy with collagen device, in primary open-angle glaucoma. This technique aims to eliminate or minimize the complications of classical trabeculectomy. MATERIAL AND METHOD: This procedure has been developed by Koslov et al. Under a limbal-base conjunctival flap and a superficial scleral flap, the ablation of a deep scleral flap takes away the external wall of Schlemm's canal, leaving only the Descemet membrane. A visible filtration across the opened Schlemm's canal and Descemet membrane is obtained. To improve the aqueous filtration, a cylindric collagen device, made from biocompatible porcine scleral tissue, known for its high water content, is fixed in the deep scleral bed with a 10/0 nylon suture. This device provides a support for the elimination route of aqueous humor and acts like a sponge, carrying the liquid by capillary action. It is sterilized by irradiation. Full guarantee against viral contamination is provided. This procedure ends in one suture (40/0 nylon) of superficial scleral flap and conjunctival closing suture. We conducted a retrospective study. Our material included 159 patients (92 males, 65 females), 2/9 eyes. The mean age was 65 years (11-91). The mean follow-up : 8 months (3-20). The types of glaucoma were: POAG: 183 eyes; juvenile POAG: 18 eyes: pigmentary glaucoma: 11 eyes; capsular glaucoma: 7 eyes, 58 eyes (40 patients) presented one or several risk factors of failure for filtering surgery. RESULTS: The mean pre-operative IOP was 24 mmHg +/- 6.60; 15.7 +/- 5.30 at the end of the follow-up (delta average IOP: 9.1 +/- 7.1). The probability success rate (IOP < or = 20 mmHg), according to the Kaplan-Meier Method, was 89% at six months, 75.6% at 16 months. With monotherapy with beta blockers, 79% at 16 months. It was better in the without risk factors group. The mean change in visual acuity was inferior to 0.1 at the end of the follow-up. Except several hyphemas, no complications of the trabeculectomy were observed. The reelevation of IOP was due to an internal obstruction (goniosynechiae or bad filtration), it was treated with Nd-Yag laser with a 2/3 of success rate. External obstruction was treated by 5FU injections into the bleb. CONCLUSION: Non penetrating deep sclerectomy with collagen device can be an excellent alternative to trabeculectomy in open and wide angles. It does not modify visual actuity. It carries less complications than trabeculectomy and the use of antimitotic agents is safer. 相似文献
90.