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71.
GT Volpato DC Damasceno WG Kempinas MVC Rudge IMP Calderon 《Reproductive biomedicine online》2009,18(6):852-858
The aim of this study was to evaluate the effect of exercise on pregnancy outcome in streptozotocin-induced diabetic Wistar rats (n = 11 animals/group). These animals were randomly assigned to sedentary (G1) and exercised groups, beginning from day 0 (G2) or 7 (G3) to day 20 of pregnancy. The moderate exercise was a swimming programme. At day 21 of pregnancy, all rats were anaesthetized and killed to obtain pregnancy outcome data. All rats presented glycaemia higher than 300 mg/dl, regardless of the exercise training. The G3 group showed higher live fetus number per implantation site and lower resorption number per implantation site compared with the G1 group. The fetal and placental mean weights per litter and the total number of ossification sites were significantly lower in the exercised groups (P < 0.05). Placental index was lower in the G2 and G3 groups compared with the G1 group. The occurrence of skeletal anomalies indicated that exercise increased the number of altered fetuses. Thus, moderate exercise achieved better outcomes by increasing the number of live births and decreasing resorption. However, exercise increased skeletal anomalies and decreased fetal and placental weights. 相似文献
72.
Barthelman M; Bair WB rd; Stickland KK; Chen W; Timmermann BN; Valcic S; Dong Z; Bowden GT 《Carcinogenesis》1998,19(12):2201-2204
Green tea polyphenols have been shown to inhibit cancer in a variety of
tumor models, including ultraviolet B (UVB)-induced non-melanoma skin
cancer. In green tea extracts, the major dry mass constituent is the family
of catechins, of which (-)-epigallocatechin-(3)-gallate (EGCG) is
considered to be important for the chemopreventive activity. EGCG has been
shown to have antioxidant properties, but there has been little progress
toward identifying the specific targets and mechanisms of its action. Using
cultured human keratinocytes, we show that UVB- induced AP-1 activity is
inhibited by EGCG in a dose range of 5.45 nM to 54.5 microM. EGCG is
effective at inhibiting AP-1 activity when applied before, after or both
before and after UVB irradiation. EGCG also inhibits AP-1 activity in the
epidermis of a transgenic mouse model. This work begins to define a
mechanism by which EGCG could be acting to inhibit UVB-induced tumor
formation.
相似文献
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76.
肺靶向顺铂白蛋白微球的研究 总被引:7,自引:0,他引:7
按正交设计筛选了用乳化一化学交联法制备肺靶向顺铂白蛋白微球的最佳制备工艺,并对微球的质量、稳定性、体内分布、动力学特性和安全性进行了系统研究。结果:微球表面圆整,平均粒径为13.13±3.55μm,药物包裹率为21.62%,释药特性符合双相动力学方程;微球在三种条件下贮放了3个月质量稳定;静脉注入小鼠体内,15min分布达高峰,97.52%浓集于肺部,2~3d内基本清除,在肺器官中的动力学特性可用二室开放性模型描述;肺器官病理切片观察,微球对肺组织无病理性损伤。 相似文献
77.
Simulated pulmonary nodules: detection with dual-energy digital versus conventional radiography 总被引:9,自引:0,他引:9
Niklason LT; Hickey NM; Chakraborty DP; Sabbagh EA; Yester MV; Fraser RG; Barnes GT 《Radiology》1986,160(3):589-593
Performance of a prototype dual-energy digital chest radiography unit in detecting calcified and noncalcified simulated pulmonary nodules was compared with that of a highly optimized, conventional system. Nodules ranging in size (0.5, 1.0, and 1.6 cm), in number (five to 11), and in calcium content (0-25 mg) were superimposed over the lungs of a frozen, unembalmed, human chest phantom. For each technique, six observers examined 50 posteroanterior projections with different randomized nodule locations. Detection consisted of locating and assigning a level of confidence to each perceived nodular opacity. The resulting plots of the true-positive fraction versus the mean number of false-positive calls per projection indicate that for both calcified and noncalcified nodules, the digital unit performed significantly better (P less than .01). 相似文献
78.
Maritza A Hobson Miklos Z Kiss Tomy Varghese Amy M Sommer Mark A Kliewer James A Zagzebski Timothy J Hall Josephine Harter Ellen M Hartenbach Ernest L Madsen 《Journal of ultrasound in medicine》2007,26(7):899-908
OBJECTIVE: Uterine abnormalities, such as leiomyomas, endometrial polyps, and adenomyosis, are often clinically associated with irregular uterine bleeding. These abnormalities can have similar B-mode characteristics but require different treatment. The objective of this study was to develop diagnostic techniques based on ultrasound strain imaging that would allow in vivo visualization and characterization of endometrial and myometrial uterine abnormalities, enabling physicians to improve diagnosis and treatment. METHODS: Ultrasound strain imaging was performed on 29 uteri removed via elective hysterectomy. An ultrasound system with a linear array transducer was used to obtain radio frequency echo data during manual freehand compressions of the tissue. Radio frequency data were post-processed with a 2-dimensional block-matching algorithm to generate strain images. RESULTS: In the uteri involved in this study, there were 19 leiomyomas, 1 case of adenomyosis, and 3 endometrial polyps observed on strain imaging. Leiomyomas appeared stiffer than the surrounding normal myometrium in strain images and were characterized by a slipping artifact at their boundary. Endometrial polyps appeared softer than the normal surrounding myometrium. The average strain contrast in small leiomyomas (<1.5 cm) compared to the myometrium was 1.75 +/- 1.14; the strain contrast was 2.50 +/- 1.15 in large leiomyomas and 0.40 +/- 0.05 in endometrial polyps. Leiomyoma strain contrast results were consistent with modulus contrast values from mechanical testing results. CONCLUSIONS: Ultrasound strain imaging can differentiate between endometrial polyps and leiomyomas. More data are necessary to validate these results and to ascertain whether other uterine abnormalities can also be differentiated. 相似文献
79.
França FO Barbaro KC Fan HW Cardoso JL Sano-Martins IS Tomy SC Lopes MH Warrell DA Theakston RD;Butantan Institute Antivenom Study Group 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2003,97(3):312-317
The association between the clinical severity of Bothrops jararaca envenoming at admission and serum venom and plasma fibrinogen concentrations before antivenom administration is reported in 137 patients admitted to Hospital Vital Brazil, Instituto Butantan, S?o Paulo, Brazil, between 1989 and 1990. Other variables such as age, gender, site of the bite, use of tourniquet and the time interval between the bite and start of antivenom therapy, spontaneous systemic bleeding, and the 20 minute whole blood clotting test (20WBCT) at admission showed no association with either severity or serum venom antigen concentration (SVAC). Mean SVAC in patients with mild envenoming was significantly lower than in the group with moderate envenoming (P = 0.0007). Patients with plasma fibrinogen concentrations > 1.5 g/L had a lower mean SVAC than patients with plasma fibrinogen concentrations < or = 1.5 g/L (P = 0.02). Those admitted with a tourniquet in place had significantly higher plasma fibrinogen concentrations than those without a tourniquet (P = 0.002). A multiple logistic regression model showed independent risk factors for severity: bites at sites other than legs or forearms, SVACs > or = 400 ng/mL, and the use of a tourniquet. Rapid quantification of SVAC before antivenom therapy might improve initial evaluation of severity in B. jararaca bites. 相似文献
80.
Charito Love Anabella S Din Maria B Tomas Tomy P Kalapparambath Christopher J Palestro 《Radiographics》2003,23(2):341-358
Bone scintigraphy with technetium-99m-labeled diphosphonates is one of the most frequently performed of all radionuclide procedures. Radionuclide bone imaging is not specific, but its excellent sensitivity makes it useful in screening for many pathologic conditions. Moreover, some conditions that are not clearly depicted on anatomic images can be diagnosed with bone scintigraphy. Bone metastases usually appear as multiple foci of increased activity, although they occasionally manifest as areas of decreased uptake. Traumatic processes can often be detected, even when radiographic findings are negative. Most fractures are scintigraphically detectable within 24 hours, although in elderly patients with osteopenia, further imaging at a later time is sometimes indicated. Athletic individuals are prone to musculoskeletal trauma, and radionuclide bone imaging is useful for identifying pathologic conditions such as plantar fasciitis, stress fractures, "shin splints," and spondylolysis, for which radiographs may be nondiagnostic. A combination of focal hyperperfusion, focal hyperemia, and focally increased bone uptake is virtually diagnostic for osteomyelitis in patients with nonviolated bone. Bone scintigraphy is also useful for evaluating disease extent in Paget disease and for localizing avascular necrosis in patients with negative radiographs. Radionuclide bone imaging will likely remain a popular and important imaging modality for years to come. 相似文献