首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   99篇
  免费   3篇
儿科学   3篇
妇产科学   3篇
基础医学   15篇
临床医学   10篇
内科学   14篇
皮肤病学   3篇
神经病学   6篇
特种医学   5篇
外国民族医学   1篇
外科学   5篇
综合类   3篇
预防医学   9篇
眼科学   5篇
药学   18篇
肿瘤学   2篇
  2023年   1篇
  2022年   1篇
  2021年   3篇
  2020年   4篇
  2019年   2篇
  2018年   8篇
  2017年   3篇
  2016年   5篇
  2015年   1篇
  2014年   4篇
  2013年   9篇
  2012年   4篇
  2011年   3篇
  2010年   6篇
  2009年   1篇
  2008年   1篇
  2007年   3篇
  2006年   6篇
  2005年   1篇
  2004年   1篇
  2003年   1篇
  2002年   4篇
  2001年   1篇
  2000年   4篇
  1999年   1篇
  1998年   1篇
  1997年   1篇
  1994年   1篇
  1992年   2篇
  1991年   2篇
  1988年   3篇
  1987年   2篇
  1986年   2篇
  1985年   3篇
  1984年   1篇
  1983年   2篇
  1979年   3篇
  1977年   1篇
排序方式: 共有102条查询结果,搜索用时 15 毫秒
1.
Placental p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) concentration and cord blood atopic markers were determined in 19 neonates. Increased placental p,p'-DDE was associated with a statistically significant increase in cord plasma interleukin (IL)-13. Furthermore, both cord plasma IL-4/interferon (IFN)-gamma and IL-13/IFN-gamma ratios were significantly positively associated with placental p,p'-DDE concentration.  相似文献   
2.
Methyl parathion (O,O-dimethylO-(4-nitrophenyl) phosphorothioate) adsorption was studied on montmorillonite, kaolinite, halloysite, natural zeolite, ion exchange resins and calcium carbonate. Methyl parathion was highly adsorbed by montmorillonite, followed by zeolite, and very little adsorption was obtained on kaolinite and halloysite. Calcium carbonate did not exhibit any adsorption. The values of the partial molar free energy ¯G were calculated for all systems. For the montmorillonite-methyl parathion system, the calculated partial molar heat of adsorption ¯H, and the conformity of the data to Freundlich equation indicated a possible physical mechanism of adsorption. Increasing acetone concentration decreases methyl parathion adsorption and dehydration increased adsorption in the nonaqueous system. Moreover, the increased adsorption on the swollen clay indicated that methyl parathion was adsorbed on the interlamellar surfaces of the clay. This was also in agreement with the results of the desorption studies, since the insecticide was not desorbed using the same aqueous acetone solution. This indicated that methyl parathion was adsorbed as a water-insoluble organic compound.  相似文献   
3.
观察25例骨髓增生异常综合征(MDS)和30例正常人外周血淋巴细胞微核。MDS患者外周血微核淋巴细胞出现率为84.00%,淋巴细胞微核率为6.68‰,显著高于对照组(P<0.005)。RAEB和RAEB-T亚型淋巴细胞微核率显著高于RA亚型(P<0.005)。MDS微核淋巴细胞多微核率与对照组差异无显著性(P>0.05)。同时检查外周血淋巴细胞染色体,MDS染色体畸变率为14.68%,显著高于对照组,且与微核率呈直线正相关(r=0.76,P0.001)。本文就MDS微核检测的意义进行了讨论。  相似文献   
4.
In the present study, the formation of glutathionyl adducts from a series of 3',4'-dihydroxy flavonoid o-quinone/p-quinone methides was investigated with special emphasis on the regioselectivity of the glutathione addition as a function of pH. The flavonoid o-quinones were generated using horseradish peroxidase, and upon purification by HPLC, the glutathionyl adducts were identified by LC/MS as well as (1)H and (13)C NMR. The major pH effect observed for the glutathione conjugation of taxifolin and luteolin quinone is on the rate of taxifolin and luteolin conversion and, as a result, on the ratio of mono- to diglutathione adduct formation. With fisetin, 3,3',4'-trihydroxyflavone, and quercetin, decreasing the pH results in a pathway in which glutathionyl adduct formation occurs in the C ring of the flavonoid, being initiated by hydration of the quinone and H(2)O adduct formation also in the C ring of the flavonoid. With increasing pH, for fisetin and 3,3',4'-trihydroxyflavone glutathione adduct formation of the quinone occurs in the B ring at C2' as the preferential site. For quercetin, the adduct formation of its quinone/quinone methide shifts from the C ring at pH 3.5, to the A ring at pH 7.0, to the B ring at pH 9.5, indicating a significant influence of the pH and deprotonation state on the chemical electrophilic behavior of quercetin quinone/quinone methide. Together the results of the present study elucidate the mechanism of the pH-dependent electrophilic behavior of B ring catechol flavonoids, which appears more straightforward than previously foreseen.  相似文献   
5.
6.
Background  The larvae of Lucilia sericata induce myiasis and transmit mycobacterial infections to humans and animals. Consequently, the blowfly should be controlled for human welfare and economic reasons.
Methods  The insecticidal effect of fenugreek ( Trigonella foenum-graecum ), celery ( Apium graveolens ), radish ( Raphanus sativus ), and mustard ( Brassica compestris ) against the third larval instars of L. sericata was evaluated, for the first time, through ingestion assays. The effect of sublethal concentrations on certain biological aspects, such as the pupation rates and adult emergence, was revealed.
Results  The LC50 values were 2.81, 4.60, 6.93, and 7.92% for fenugreek, celery, radish, and mustard, respectively. The adverse effects on larval treatment also included the survival of pupae and adults. The pupation rate was strongly decreased after treatment with 16% fenugreek and celery. Moreover, adult emergence was suppressed after treatment of larvae with 8% mustard, 12% radish, and 16% fenugreek and celery oils. The number of emerged males exceeded the number of females, which could lead to population decline. Morphologic abnormalities of larvae, pupae, and adults were recorded after treatment with all tested oils.
Conclusion  The results suggest that oils may represent new and safe potential insecticides for the control of blowflies.  相似文献   
7.
We investigated fasting gallbladder volume and gallbladder emptying in response to a fatty meal in 20 patients with asymptomatic gallstones and compared the results with findings from healthy controls. Compared with control subjects without gallstones, the majority of patients with gallstones exhibited a higher resting gallbladder volume, less fractional emptying after a fatty meal, and a higher postmeal residual volume. These abnormalities all appeared to stem from an abnormally high resting gallbladder volume. Whether the increased gallbladder volume and decreased postprandial fractional emptying in the gallstone patients represents a primary or secondary abnormality remains to be determined. The results suggest that in some patients decreased gallbladder contractility may contribute to gallstone development or proliferation.  相似文献   
8.
The retroperitoneal spaces revisited   总被引:11,自引:0,他引:11  
  相似文献   
9.
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号