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   38篇
  免费   1篇
  2023年   1篇
  2021年   1篇
  2018年   1篇
  2017年   1篇
  2015年   1篇
  2014年   2篇
  2013年   3篇
  2012年   2篇
  2011年   4篇
  2009年   3篇
  2008年   1篇
  2007年   1篇
  2006年   1篇
  2004年   2篇
  2003年   2篇
  1987年   1篇
  1981年   1篇
  1977年   2篇
  1976年   2篇
  1975年   2篇
  1972年   1篇
  1967年   1篇
  1962年   1篇
  1960年   1篇
  1958年   1篇
排序方式: 共有39条查询结果,搜索用时 15 毫秒
1.
We assessed the presence of alpha-fetoprotein (AFP) complexed with IgM (AFP-IgM IC) in serum of patients affected by hepatocellular carcinoma (HCC), cirrhosis and chronic hepatitis as well as in healthy subjects by means of a dedicated ELISA assay. The amount of AFP-IgM IC was expressed in arbitrary units (AU) on a reference standard curve. Free AFP (FAFP) levels were determined in parallel in each sample by means of an automated immunoassay system. The mean serum concentration of AFP-IgM IC was significantly higher in HCC patients (mean +/- SD: 1378.3 +/- 2935.7 AU/mL) than in cirrhotic patients (129.8 +/- 261.4 AU/mL) and in patients with chronic hepatitis (80.9 +/- 168.9 AU/mL) (p < 0.01). HCC patients had FAFP values above the 20 ng/mL cutoff in 44% of cases (22/50) and AFP-IgM IC values above the 120 AU/mL cutoff in 60% of cases (30/50). The occurrence of the free and IgM-complexed form of circulating AFP did not overlap, and 82% of patients (41/50) were positive for at least one marker. The results indicate that AFP-IgM IC is a complementary serological marker to FAFP and that the combination of these biomarkers may be useful in the diagnosis of liver cancer.  相似文献   
2.
The phenology of the vegetation covering north Asia (mainly Siberia) and its spatial characterstics were investigated using remotely sensed normalized difference vegetation index (NDVI) data. The analysis used the weekly averaged NDVI over 5 years (1987-1991) using the second-generation weekly global vegetation index dataset (0.144 degrees x 0.144 degrees spatial resolution). In the seasonal NDVI cycle, three phenological events were defined for each pixel: green-up week (NDVI exceeds 0.2), maximum week, and senescence week (NDVI drops below 0.2). Generally there was a west-early/east-late gradient in the three events in north Asia. In the zonal transect between 45 degrees and 50 degrees N, the timing of green-up, maximum, and senescence near 60 degrees E (Kazakh) was about 3.4, 8.7, and 13.4 weeks earlier than near 110 degrees E (Mongolia) respectively. It has been suggested that vegetation near Kazakh only flourishes during a short period when water from snow melt is available from late spring to early summer. In Mongolia, abundant water is available for the vegetation, even in midsummer, because of precipitation. In the 50-60 degrees N zonal transect, the green-up and maximum near 40 degrees E were about 3.8 and 3.9 weeks earlier than near 115 degrees E, respectively. As for the week of senescence, there was no clear west-east trend. This west-to-east phenological gradient was related to the weekly cumulative temperature (over 0 degrees C). Weeks in which the cumalative temperature exceeded 40 degrees C and 140 degrees C had a similar west-east distribution to green-up and maximum NDVI.  相似文献   
3.
4.

Background

This study evaluates the outcome and complications of decompressive cervical Laminectomy and lateral mass screw fixation in 110 cases treated for variable cervical spine pathologies that included; degenerative disease, trauma, neoplasms, metabolic-inflammatory disorders and congenital anomalies.

Methods

A retrospective review of total 785 lateral mass screws were placed in patients ages 16-68 years (40 females and 70 males). All cases were performed with a polyaxial screw-rod construct and screws were placed by using Anderson-Sekhon trajectory. Most patients had 12-14-mm length and 3.5 mm diameter screws placed for subaxial and 28-30 for C1 lateral mass. Screw location was assessed by post operative plain x-ray and computed tomography can (CT), besides that; the facet joint, nerve root foramen and foramen transversarium violation were also appraised.

Results

No patients experienced neural or vascular injury as a result of screw position. Only one patient needed screw repositioning. Six patients experienced superficial wound infection. Fifteen patients had pain around the shoulder of C5 distribution that subsided over the time. No patients developed screw pullouts or symptomatic adjacent segment disease within the period of follow up.

Conclusion

decompressive cervical spine laminectomy and Lateral mass screw stabilization is a technique that can be used for a variety of cervical spine pathologies with safety and efficiency.  相似文献   
5.
6.
Inorganic pyrophosphatase activities extracted from vegetative cells and spores of Bacillus megaterium were compared and found to be similar in behavior on polyacrylamide gel electrophoresis, in metal and pH requirements for activity, and in response to inhibitors. In the sporulating cell, an additional electrophoretic species of the enzyme was observed which could be partially converted to the principal form by treatment with Mn(++); both forms of the enzyme required Mn(++) for stabilization in solution as well as for activity.  相似文献   
7.
8.
Aortic grafts of polyurethane in dogs   总被引:2,自引:0,他引:2  
  相似文献   
9.
Tissue inflammation and multiple cellular responses in the compensatory enlarged plantaris (OP Plt) muscle induced by surgical ablation of synergistic muscles (soleus and gastrocnemius) were followed over 10 weeks after surgery. Contralateral surgery was performed in adult Wistar male rats. Cellular responses in muscle fibers, blood vessels and nerve fibers were analyzed by immunohistochemistry and electron microscopy. Severe muscle fiber damage and disappearance of capillaries associated with apparent tissue edema were observed in the peripheral portion of OP Plt muscles during the first week, whereas central portions were relatively preserved. Marked cell activation/proliferation was also mainly observed in peripheral portions. Similarly, activated myogenic cells were seen not only inside but also outside of muscle fibers. The former were likely satellite cells and the latter may be interstitial myogenic cells. One week after surgery, small muscle fibers, small arteries and capillaries and several branched-muscle fibers were evident in the periphery, thus indicating new muscle fiber and blood vessel formation. Proliferating cells were also detected in the nerve bundles in the Schwann cell position. These results indicate that the compensatory stimulated/enlarged muscle is a suitable model for analyzing multiple physiological cellular responses in muscle–nerve–blood vessel units under continuous stretch stimulation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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