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排序方式: 共有3444条查询结果,搜索用时 234 毫秒
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T C Cook R E Laporte R A Washburn N D Traven C W Slemenda K F Metz 《Medicine and science in sports and exercise》1986,18(6):653-657
Physical activity has been associated with reduced risk of coronary heart disease. A mechanism for the reduced risk may be through increased high density lipoprotein cholesterol (HDL-C) and subfractions, in particular HDL2-C. Research associated with increased physical activity investigating HLD-C have assessed the effects of intense aerobic activity. The current research evaluated the relationship between low intensity, long duration activity to HDL-C and subfractions in 35 active postal carriers. Measurements of physical activity via the Large Scale Integrated monitor and reported miles walked, and lipoproteins were assessed at 3-month intervals over a 1-year period. Reported miles walked/day (5.3) was significantly correlated with HLD2-C (r = 0.50, P = 0.003) and approached significance for HDL-C (r = 0.29, P = 0.06). The Large Scale Integrated measures were correlated with HDL-C (r = 0.44, P = 0.008) and HDL2-C (r = 0.44, P = 0.007). Controlling for either age, alcohol consumption, body mass index, or leisure time activity did not reduce the relationship between reported miles walked or Large Scale Integrated readings and HDL2-C, suggesting that the increased HDL-C was the result of long duration, low intensity physical activity. 相似文献
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Digital mammography. ROC studies of the effects of pixel size and unsharp-mask filtering on the detection of subtle microcalcifications 总被引:3,自引:0,他引:3
H P Chan C J Vyborny H MacMahon C E Metz K Doi E A Sickles 《Investigative radiology》1987,22(7):581-589
We investigated the spatial resolution requirement and the effect of unsharp-mask filtering on the detectability of subtle microcalcifications in digital mammography. Digital images were obtained by digitizing conventional screen-film mammograms with a 0.1 X 0.1 mm2 pixel size, processed with unsharp masking, and then reconstituted on film with a Fuji image processing/simulation system (Fuji Photo Film Co., Tokyo, Japan). Twenty normal cases and 12 cases with subtle microcalcifications were included. Observer performance experiments were conducted to assess the detectability of subtle microcalcifications in the conventional, the unprocessed digital, and the unsharp-masked mammograms. The observer response data were evaluated using receiver operating characteristic (ROC) and LROC (ROC with localization) analyses. Our results indicate that digital mammograms obtained with 0.1 X 0.1 mm2 pixels provide lower detectability than the conventional screen-film mammograms. The detectability of microcalcifications in the digital mammograms is improved by unsharp-mask filtering; the processed mammograms still provide lower accuracy than the conventional mammograms, however, chiefly because of increased false-positive detection rates for the processed images at each subjective confidence level. Viewing unprocessed digital and unsharp-masked images in pairs resulted in approximately the same detectability as that obtained with the unsharp-masked images alone. However, this result may be influenced by the fact that the same limited viewing time was necessarily divided between the two images. 相似文献
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Leonidas JC; Berdon WE; Valderrama E; Neveling U; Schuval S; Weiss SJ; Hilfer C; Godine L 《Radiology》1996,198(2):377
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Kath R.; Hoftken K.; Otte C.; Metz K.; Scheulen M. E.; Hulskamp F.; Seeber S. 《Annals of oncology》1993,4(7):585-590
BACKGROUND:: A soluble 105 kD neu-related protein is detectable in conditionedmedium from breast cancer cells expressing the neu-oncogeneproduct and in serum of nude mice bearing tumors that overexpressneu-oncogene PATIENTS AND METHODS:: In 100 patients with primary (n - 33) relapse-free (n - 6) andmetastatic (n - 61) breast carcinoma the serum levels of thesoluble new-related protein were investigated by ELISA techniques.Median age was 57 years, range 2689 years. RESULTS:: The neu-protein serum levels were below 40 HNU/ml (human neu-antigenunit) in 72 patients and 40 or more HNU/ml in 28 patients. In30 patients with primary breast carcinoma, tested before mastectomy,all serum- neu-protein samples were negative. However, 26 of61 metastazised patients (43%) were serum-neu-protein-positive.In disseminated disease (n 61), serum-neu-protein-positivitywas more likely to be seen in patients with visceral metastases(18/33 54%), than in patients with nonvisceral metastases(8/28 28%). Furthermore, monitoring of the serum-neu-proteinlevels reflected clinical course. For 53 patients original paraffin-embeddedtumor material was available for studying immunohistochemicalneu-protein expression. In 39/53 (73%) patients immunohistochemicaland ELISA data showed corresponding results. In 27/30 (90%)patients, from whom sera and tissue could be obtained at thesame time at primary mastectomy, results of immunohistochemistryin primary tumor and serum ELISA were negative and mutuallyconfirmatory. However, the other three patients were positivefor immunohistochemical neu-protein expression in primary tumorbut negative for serum-neu-protein expression. CONCLUSIONS:: Our results suggest that patients with advanced breast cancerand an elevated serum-neu-protein level may have a poor clinicaloutcome. This test might be a useful tool for monitoring patientswith advanced breast carcinoma, but not those with early disease.Further prospective studies are warranted to elucidate the questionof whether this test can contribute to determining prognosisand treatment strategies. breast carcinoma, c-erb-B2, HER-2, neu, oncogene, pl85 相似文献
9.
JC Sitek† M Loeb‡ JR Ronnevig¶ 《Journal of the European Academy of Dermatology and Venereology》2007,21(7):891-896
BACKGROUND: Since 1997, a number of trials have shown promising results in treating generalized vitiligo with narrowband ultraviolet B (UVB) both in adults and children. However, there is little knowledge concerning the duration and permanency of the treatment-induced repigmentation. OBJECTIVE: Our main objective was to perform a follow-up trial of successfully treated patients receiving narrowband UVB for generalized vitiligo. METHODS: We have investigated to what degree the treatment-induced repigmentation remains stable for up to 2 years post-treatment. We performed an initial open trial including 31 patients with generalized vitiligo. They received narrowband UVB thrice weekly for up to 12 months. Patients experiencing > 75% repigmentation were defined responders and were included in the follow-up trial. Responders were followed every 6 months for up to 2 years after cessation of treatment. We observed the pigmentation status and registered any changes indicating loss of pigmentation and relapse. RESULTS: Eleven of the 31 treated patients were included in the follow-up trial. Six patients had relapse and five patients had stable response 24 months after cessation of treatment. Four out of six relapses were within 6 months post-treatment. CONCLUSION: In our study population of 31 patients with generalized vitiligo, five patients (16%) experienced > 75% stable repigmentation 2 years after cessation of a treatment programme of up to 1 years narrowband UVB therapy. 相似文献
10.
Ongoing pregnancies after intracytoplasmic injection using cryopreserved testicular spermatozoa 总被引:4,自引:2,他引:2
Perraguin-Jayot S; Audebert A; Emperaire JC; Parneix I 《Human reproduction (Oxford, England)》1997,12(12):2706-2709
We report two clinical pregnancies occurring after intracytoplasmic sperm
injection (ICSI) using cryopreserved spermatozoa obtained from testicular
biopsy, made in two different infertility situations in our clinic. The
first patient showed a secretory azoospermia associated with elevated serum
follicular stimulating hormone (FSH) level and spermiogenesis maturation
arrest. The second patient was affected by azoospermia resulting from
bilateral epididymal obstruction. Spermatozoa present in the wet
preparation of testicular biopsy made on the day of scrotal exploration
were cryopreserved within the testicular tissue for both men.
Intracytoplasmic injections were performed at a later date, using
spermatozoa prepared from frozen-thawed tissues. In each case, three
embryos were obtained and transferred in utero. The transfers resulted in a
twin pregnancy for the first case, and in a singleton pregnancy for the
second. Living foetuses were seen in the ultrasound scan at the 7th week
and both pregnancies are proceeding to date beyond 30 weeks without
complications.
相似文献