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991.
AIM OF THE STUDY: This investigation evaluated the effect of a hydroethanolic extract of Baccharis trimera on pregnant Wistar rats, once the plant is well-known consumed in pregnancy and little is known on its potentially toxic effects on pregnant women. MATERIAL AND METHODS: Thirty-five female rats were distributed into three groups. Those in treatments 1 and 2 were given 8.4 mg/kg of the extract orally from gestational day (GD) 1 to 19 and from GD 6 to 15, respectively, whereas those in the control group received distilled water orally from GD 1 to 19. Body weights were recorded on GD 1, 6, 15, and 20. On GD 20 animals were anesthetized, blood samples were collected and maternal livers, kidneys, and spleens were weighed and processed for histological studies. RESULTS: No clinical signs of maternal toxicity and no changes in hematological parameters were observed. Urea levels and kidney weights differed significantly between animals receiving treatment 1 and controls. Histopathological alterations were found in kidneys and livers in both treatment groups. CONCLUSIONS: The hydroethanolic extract of Baccharis trimera administered to pregnant rats at 8.4 mg/kg was toxic to maternal kidney and liver cells, although such alterations are reversible once administration is discontinued.  相似文献   
992.
The Gingko biloba extract is contraindicated during pregnancy and lactation due to the lack of information about its effects on these reproductive phases. Previous studies have shown that G. biloba extract contains components with estrogenic and antiestrogenic activities, thus nursing dams treated with the extract of this plant could show reduction in milk production, resulting in malnutrition and poor development of pups. This work analyzes the postnatal development of pups, whose mothers were treated with G. biloba extract during the lactation period. Nursing Wistar rats received 3.5 mg/kg/day of G. biloba aqueous extract, corresponding to the highest human dose. Clinical signs of maternal toxicity were evaluated. The growth rate, viability, survival during treatment and lactation indices of the pups were calculated. The physical, motor and sensorial development of the pups was also evaluated. No maternal signs of toxicity were observed. As there were no biological differences between control and G. biloba treated pups, it is possible to assume that, in this experimental design, the administration of G. biloba aqueous extract to nursing rats during the lactation period seems to be devoid of toxic effect to mothers and to the physical, motor and sensory development of the pups.  相似文献   
993.
An activity-guided fractionation of Virola sebifera Aubl. methylene chloride-soluble fraction provided novel 3,5-dihydro-2-(1'-oxo-3'-hexadecenyl)-2-cyclohexen-1-one (3), two known lignans (1, 2) and dehydro hexadecanoyl resorcinol (4). Isolation and purification were conducted with the application of column chromatography and structures were assigned by spetral analysis (1D and 2D NMR, HREIMS). Compounds 1-4 were evaluated for cytotoxic activities against human tumour cell lines UACC62 (melanoma), MCF-7 (breast), NCI 460 (lung, non-small cells), OVCAR03 (ovarian), PC-03 (prostate), HT-29 (colon), 786-0 (renal) and NCI-ADR (breast expressing phenotype multiple drugs resistance) in vitro. The new polyketide (3) showed selectivity against human OVCAR03 and NCI-ADR cell lines, ranging from 2 to 4 microg/mL.  相似文献   
994.
ETHNOPHARMACOLOGICAL RELEVANCE: Arrabidaea chica Verlot. (Bignoniaceae), popularly known as Crajiru, has been traditionally used as wound healing agent. AIM OF THE STUDY: Investigate in vitro and in vivo healing properties of Arrabidaea chica leaves extract (AC). MATERIALS AND METHODS: AC was evaluated in vitro in fibroblast growth stimulation (0.25-250 microg/mL) and collagen production stimulation (250 microg/mL) assays. Allantoin (0.25-250 microg/mL) and vitamin C (25 microg/mL) were used as controls respectively. DPPH and Folin-Ciocalteau assays were used for antioxidant evaluation, using trolox (0.25-250 microg/mL) as reference antioxidant. To study wound healing properties in rats, AC (100mg/mL, 200 microL/wound/day) was topically administered during 10 days and wound area was evaluated every day. Allantoin (100mg/mL, 200 microL/wound/day) was used as standard drug. After treatment, wound sites were removed for histopathological analysis and total collagen determination. RESULTS: AC stimulated fibroblast growth in a concentration dependent way (EC50=30 microg/mL), increased in vitro collagen production and demonstrated moderate antioxidant capacity. In vivo, AC reduced wound size in 96%, whereas saline group showed only 36% wound healing. CONCLUSION: AC efficiency seems to involve fibroblast growing stimulus and collagen synthesis both in vitro and in vivo, beyond moderate scavenging activity, corroborating Crajiru folk use.  相似文献   
995.
Introduction: In women, most malignant effusions are from breast and ovary primary carcinomas that have metastasized to body cavity fluids (pleural, peritoneal and pericardial). When carcinoma is diagnosed in effusions, it is not possible to identify its site of origin solely by cytology (morphology); therefore, immunocytochemistry is used as a complementary method. There are no immunocytochemical markers with 100% sensitivity and specificity for identifying carcinoma primary site. The markers most used are TTF-1 for the lung, GATA-3 for the breast, and PAX-8 for the ovary. The aim of this study was to evaluate the sensitivity and specificity of a panel including these markers for detecting the primary site of carcinoma in effusions. Methods: Samples of pleural, pericardial, and peritoneal effusions and peritoneal washings with carcinoma of known primary site from women (n = 60) and men (n = 18) were prepared by using the cell block method, and immunocytochemistry was performed to evaluate the expression of primary site markers (TTF-1, PAX-8, and GATA-3). Results: In women, the breast was the most frequent primary site of metastatic carcinoma to both pleural and pericardial cavities, followed by the lung, whereas the ovary was the most frequent primary site of carcinoma within peritoneal effusions and washings, followed by the gastrointestinal tract (stomach or intestine). The expected profiles for carcinomas of the most common primary sites were: breast (GATA-3 (+), PAX-8 (-), TTF-1 (-)), ovary (PAX-8 (+), GATA-3 (-), TTF-1 (-)), lung (TTF-1 (+), PAX-8 (-) GATA-3 (-)) and gastrointestinal tract (PAX-8 (-), GATA-3 (-), TTF-1 (-)). These were observed in 88.23% (45/51) of women’s samples with carcinoma from these primary sites. By using TTF-1 as the sole primary site marker, 6.25% of carcinomas of primary site other than the lung would have been misdiagnosed. Conclusion: An initial panel of markers including GATA-3, PAX-8, and TTF-1 allows, with high sensitivity and specificity, the identification or exclusion of frequent primary sites of carcinoma in effusions from women. Our results highlight the importance of using a panel of markers to avoid misidentification of the primary site of tumor.  相似文献   
996.
997.
目的 探讨自体组织替代治疗超长段尿道狭窄对勃起功能的影响.方法 回顾性分析2007年1月至2009年1月采用不同自体组织补片(阴囊纵隔、包皮内板、口腔黏膜)Onlay术式替代治疗超长段男性尿道狭窄患者的临床资料,并随访患者ⅡEF-5评分、QOL评分及最大尿流率,并与术前相应情况进行分析.结果 根据研究标准收集23份有效数据.患者术前及术后3、6、12个月QOL评分分别为5.22±0.75、1.22±1.40、1.82±1.17、2.07±0.46,最大尿流率分别为(3.93±3.62)、(22.46±4.65)、(23.81±6.22)、(21.52±7.44)ml/s,术后不同时期均较术前明显改善(P<0.01).术前及术后3、6、12个月ⅡEF-5评分分别为14.47±9.55、14.70±5.32、14.26±3.29和14.58±3.62,组间比较差异无统计学意义(P>0.05).9例狭窄部位累及至后尿道者术后3、6、12个月ⅡEF-5评分分别为11.67±2.59、12.35±1.83、13.19±1.67,14例单纯前尿道狭窄者分别为17.79±6.42、16.57±4.78、16.01±3.85,2组间比较差异均有统计学意义(P<0.05).狭窄累及后尿道患者多元线性回归分析中,年龄、受伤时间及尿道狭窄段长度与替代术后ⅡEF-5评分呈多元线性相关.结论 自体组织替代治疗男性超长段尿道狭窄对勃起功能影响不明显;狭窄段累及后尿道时可能对患者勃起功能产生一定影响.患者年龄和受伤时间对勃起功能有协同影响作用.
Abstract:
Objective To investigate the effect of substitutive reconstruction of long urethral stricture on male erectile function. Methods From January 2007 to January 2009, 23 patients with anterior or posterior long urethral stricture were accepted for a variety of onlay substitutive procedures, including lingual mucosa, perputial skin, and mid-scrotal skin. During the follow-up, data from the International Index of Erectile Function-5 (ⅡEF-5) questionnaire and the Quality of Life (QOL) questionnaire as well as maximal flow rate were recorded. All data were compared with those obtained before surgery. Results Significant improvement in QOL (1.22 ± 1.40, 1.82 ± 1. 17,2.07± 0.46) and maximal flow rate (22.46± 4.65, 23.81 ± 6.22, 21.52 ±7.44 ) could be observed 3, 6 and 12 months after surgery compared with those before surgery (5. 22 ± 0. 75, 3. 93 ± 3. 62)(P<0.01). No significant differences in the responses to the ⅡEF-5 questionnaire were observed among all patients during the follow-up (P>0. 05). At the 3, 6 and 12 months after procedure,scores of ⅡEF-5 in patients with anterior urethral stricture ( 17.79 ± 6.42, 16. 57 ± 4. 78, 16.01 ±3.85) were significantly higher than those with posterior urethral stricture (11.67 ± 2.59, 12.35 ±1.83,13. 19±1.67, P<0.05). In patients with posterior urethral stricture, the multiple linear regression showed that age, time interval of injury and length of stricture were related to the ⅡEF-5score (P<0.05). Conclusions Substitutive reconstruction for treating the long urethral stricture has little effect on male erectile function. But the location of stricture, especially extended to posterior urethra, may have impact on the erectile function.  相似文献   
998.
目的 分析未净化Z:ZCLA长爪沙鼠封闭群繁育和生长指标,并利用直接测序法分析其遗传稳定性.方法 随机选择40对Z:ZCLA长爪沙鼠,记录其繁殖胎次、产子数等指标,分析其仔鼠的生长发育情况.遗传稳定性分析选择Z:ZCLA长爪沙鼠非同胞、非亲代个体33只,提取肝脏基因组DNA,PCR扩增D-Loop序列,产物纯化后双向测序,测序结果与Z:ZCLA长爪沙鼠标准序列比对.结果 Z:ZCLA长爪沙鼠每胎产仔7只,胎间隔多在20~60d间,雄性体重高于雌性.遗传稳定性分析检测发现33只Z:ZCLA长爪沙鼠序列与标准序列完全一致.结论 Z:ZCLA长爪沙鼠群体内未发现遗传多态性,说明该群体具有较好的遗传稳定性.  相似文献   
999.
复杂性尿道狭窄或闭锁的处理一直是泌尿外科最棘手的难题之一,尤其是对初次或再次治疗失败后的复杂性超长段尿道狭窄或闭锁(> 14 cm)患者的治疗,作者在治疗复杂性尿道狭窄及其并发症中取得了一系列的原创性成果.与国内外的同类研究比较,主要有以下发现和创新点.①在国际上首次提出并证实结肠黏膜可作为尿道替代物;临床治疗55例超长段尿道狭窄(平均15.2 cm)的结果提示结肠黏膜具有材源丰富、易于剥离、抗感染力强、皱缩率低等优点,适于14 cm以上尿道的重建,尤其是多次治疗失败的复杂性超长段尿道狭窄.②在国际上首次建立新型分期手术治疗复杂性超长段狭窄或闭锁,临床应用11例,疗效显著,为难治性前后尿道间长段狭窄或闭锁提供了一个新的思路.③在国际上首次阐述舌黏膜尿道重建的病理学特征及转归,建立大面积舌黏膜取材新技术;在国内率先开展舌黏膜尿道成形术,样本量为国内外最大.④在国际上首次建立了尿道压客观量化指标(90 cmH2O或较基础压提高40 ~50 cmH2O),用于评估球部尿道悬吊术中尿道压力.从而提高了手术成功率,减少了并发症,取得了显著治疗效果.该系列研究成果先后获省部科技进步一等奖和多项二等奖.  相似文献   
1000.
目的:评价肾交感神经刺激(Renal sympathetic nerves stimulation,RSNS)对全身交感神经系统的影响。方法12只成年杂种犬随机分为两组:假手术组(Sham组,n=6)和肾交感神经刺激组(RSNS组,n=6)。RSNS组经左肾动脉外膜给予持续2 h高频电刺激,刺激参数:频率20 Hz,脉宽0.1 ms,刺激强度随血压进行调整,以保持血压较刺激前升高10%;假手术组在左肾动脉附近寻找一处体表皮肤给予以同样2 h高频电刺激。分别于基础状态和2 h刺激末检测血压(BP)、心率(HR)、心率变异性(HRV)和血清去甲肾上腺素(NE)浓度。结果与基础状态比较,Sham组成年杂种犬2 h末BR、HR、交感神经活性和血清去甲肾上腺素浓度比较差异均无统计学意义(P>0.05)。与基础状态比较,RSNS可以明显提高成年杂种犬BR、交感神经活性和血清去甲肾上腺素浓度,差异有统计学意义(P<0.05)。结论肾交感神经刺激可以明显提高全身交感神经系统活性。  相似文献   
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