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排序方式: 共有5197条查询结果,搜索用时 31 毫秒
41.
Human prostate cancer (PC) cell lines possess epidermal growth factor (EGF) receptors and secrete EGF-related polypeptides. We used an EGF receptor-blocking antibody (anti-EGF.R) to demonstrate a functional autocrine loop, as well as the interaction between this and the effects of linoleic acid (LA), an omega-6 fatty acid, on PC cell growth. The anti-EGF.R competed effectively with [125I]EGF for receptors on DU145 PC cells, and on a high-passage DU145 variant (DU145M); when added to the culture medium, it suppressed both DU145 and DU145M cell growth in a dose-dependent manner. LA, a precursor for eicosanoid synthesis, had little effect on DU145 cell growth rate but stimulated DU145M growth in a concentration-related manner over a range of 0.25-2.0 micrograms/ml. anti-EGF.R (10(-9) M) caused suppression of LA-stimulated growth of DU145M cells in serum-free medium, which was prevented by the addition of 2 nM EGF. We conclude that an EGF.R-mediated autocrine loop is involved in PC cell growth regulation and that at least one site of action may be the synthesis of eicosanoids from their LA precursor. 相似文献
42.
Oscillatory motion of the normal cervical spinal cord 总被引:2,自引:0,他引:2
43.
Periosteal Ewing sarcoma 总被引:3,自引:0,他引:3
44.
Francis J. Podbielski Guillermo D. Marquez Darren G. Nelson Nancy A. Diettrich Mark M. Connolly 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》1997,1(1):75-77
A lung carcinoma with tumor involving more than one lobe or in close proximity to the mainstem bronchus often requires pneumonectomy for surgical cure. Inflammation, bulky tumors, and dense adhesions limit the operative field of vision and may result in the abandonment of procedures with potential for complete extirpation. This case illustrates the utility of thoracoscopy in visualization of the hilum and other neurovascular structures in a patient with a proximal tumor and dense intrathoracic adhesions. Successful resection was made possible by use of combined open and thoracoscopic modalities. 相似文献
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46.
In a prospective, randomized study of insemination with donor semen,
intracervical insemination by straw was compared with insemination using a
cervical cap with an intracervical reservoir. A total of 91 patients
completed 486 treatment cycles. There were no significant differences in
age, parity, indication for insemination by donor, or method of cycle
monitoring between women who became pregnant and those who did not conceive
with either insemination method. In 236 standard intracervical insemination
cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients
conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude
pregnancy rates and the cumulative pregnancy rates calculated by the
Kaplan-Meier life-table method were significantly different (chi(2)-test, P
< 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates
in artificial insemination with cryopreserved donor semen may be improved
by the use of a cervical cap when compared to cervical insemination by
straw. The use of the cervical cap may prolong the exposure of the
spermatozoa to the cervical mucus and prevent the backflow of semen into
the vagina.
相似文献
47.
Charles M Lombardi Alison D Silhanek Fiona G Connolly Lester N Dennis 《The Journal of foot and ankle surgery》2002,41(2):96-103
The purpose of this study was to examine the effect of first metatarsophalangeal arthrodesis on the sagittal plane orientation of the first ray and the medial longitudinal arch. Lateral weightbearing radiographs of 48 patients (54 feet) having undergone the procedure were retrospectively reviewed. Patients were separated into three groups based on their preoperative diagnosis: hallux rigidus, hallux valgus, or rheumatoid forefoot deformity. First metatarsal declination, talometatarsal, talar declination, calcaneal inclination, and talocalcaneal angles were measured on pre- and postoperative radiographs. Multivariate analysis of variance determined that there was a significant postoperative change (p < .001) in angular measurements, particularly in the first metatarsal declination, talometatarsal, and talocalcaneal angles. There was also a significant difference (p < .01) in the angular measurements between the hallux rigidus group and the other two groups. However, the amount of change from pre- to postoperatively did not vary significantly between the groups. A calculation of Pearson correlation coefficients found no significant correlation between the hallux dorsiflexion angle and changes in angular measurements. The radiographic changes found in this study support Hicks' windlass model: fixed dorsiflexion of the hallux causes plantarflexion of the first ray and an increase in the medial longitudinal arch. 相似文献
48.
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50.
Meniscal abnormalities: prospective correlation of double-contrast arthrography and arthroscopy 总被引:2,自引:0,他引:2
In a prospective study conducted over a 12-month period, 30 patients underwent double-contrast arthrography of the knee followed by arthroscopic study. An 80% correlation rate was found between results. Arthrography had a higher rate of accuracy (93%) than arthroscopy (84%) and had a 7% false-positive and 0% false-negative rate. A commonly overlooked arthrographic sign--the triple-S or stuck sail sign--was 91% accurate in the prediction of meniscal tears. The complementary nature of the two examinations is discussed. 相似文献