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   101篇
  免费   7篇
  国内免费   3篇
儿科学   3篇
基础医学   20篇
口腔科学   2篇
临床医学   12篇
内科学   20篇
神经病学   11篇
特种医学   4篇
外科学   13篇
预防医学   7篇
药学   5篇
肿瘤学   14篇
  2023年   2篇
  2022年   2篇
  2021年   8篇
  2020年   4篇
  2019年   5篇
  2018年   3篇
  2017年   7篇
  2016年   2篇
  2015年   6篇
  2014年   5篇
  2013年   8篇
  2012年   12篇
  2011年   9篇
  2010年   3篇
  2009年   5篇
  2008年   4篇
  2007年   4篇
  2006年   6篇
  2005年   4篇
  2004年   4篇
  2003年   3篇
  2002年   2篇
  2001年   1篇
  1998年   1篇
  1993年   1篇
排序方式: 共有111条查询结果,搜索用时 13 毫秒
91.
A 50-year-old woman with jaw pain and a history of bisphosphonate use was shown on radiography to have ill-defined soft tissue calcifications overlying the maxilla, mandible, and zygomatic bones bilaterally. The bones were normal. CT revealed similar findings. Although a broad imaging differential diagnosis was initially considered, further questioning of the patient revealed a history of facial injections with a calcium hydroxylapatite product for cosmetic purposes. The appearance of this increasingly popular treatment should be recognized to avoid errors in interpretation.  相似文献   
92.
Introduction. There is significant geographic variation in the etiology and prognosis of acute liver failure (ALF). Since, little information is available for Latin America. We analyzed ALF mortality trends in Mexico.Material and methods. The rates of mortality attributable to ALF were obtained for 1998 to 2009 from the National System of Health Information in Mexico and analyzed according to date, etiology, sex, age and geographic characteristics through graphical assessment and joinpoint regression.Results. From 1998 to 2009, 2,193 ALF-related deaths were reported. A threefold increase in ALF mortality was observed during the period from 1998 to 2009 (the global mortality rate increased from 13.1 to 40.2 deaths per 10,000,000 inhabitants). The most significant increase was observed for viral etiologies after 2006, affecting people 45 years old and over.Conclusion. ALF-related deaths have increased since 2006. Although we cannot speculate on the specific causes of this increase, it may reflect improvements in the access of vulnerable populations to health care.  相似文献   
93.
94.
Some natural and synthetic protease inhibitors (PI), such as the Bowman-Birk PI from soybean, have anticancer effects. We previously purified and characterized a Bowman-Birk-type PI from Tepary bean (Phaseolus acutifolius) seeds (TBPI). A semipure protein fraction containing this inhibitor, when tested its in vitro effect on transformed cells, showed a differential cytotoxic effect, as well as an increase in cell attachment to culture dishes. In this article we report that lectins were responsible for the cytotoxic effect previously observed, exhibiting a differential, antiproliferative effect on nontransformed cells and on different lineages of cancer cells. Although the purified TBPI lacked cytotoxicity, it was found to be responsible for the increase in cell adhesion, decreasing culture dishes’ extracellular matrix degradation, leading to a decrease of the in vitro cell invasion capacity. This effect coincided with the suppression of Matrix Metalloproteinase-9 activity. These results indicate that Tepary bean seeds contain at least 2 different groups of bioactive proteins with distinct effects on cancer cells.  相似文献   
95.
Cellular microenvironments are important in coaxing cells to behave collectively as functional, structured tissues. Important cues in this microenvironment are the chemical, mechanical and spatial arrangement of the supporting matrix in the extracellular space. In engineered tissues, synthetic scaffolding provides many of these microenvironmental cues. Key requirements are that synthetic scaffolds should recapitulate the native three-dimensional (3D) hierarchical fibrillar structure, possess biomimetic surface properties and demonstrate mechanical integrity, and in some tissues, anisotropy. Electrospinning is a popular technique used to fabricate anisotropic nanofiber scaffolds. However, it suffers from relatively low production rates and poor control of fiber alignment without substantial modifications to the fiber collector mechanism. Additionally, many biomaterials are not amenable for fabrication via high-voltage electrospinning methods. Hence, we reasoned that we could utilize rotary jet spinning (RJS) to fabricate highly aligned hybrid protein-polymer with tunable chemical and physical properties. In this study, we engineered highly aligned nanofiber constructs with robust fiber alignment from blends of the proteins collagen and gelatin, and the polymer poly-ε-caprolactone via RJS and electrospinning. RJS-spun fibers retain greater protein content on the surface and are also fabricated at a higher production rate compared to those fabricated via electrospinning. We measured increased fiber diameter and viscosity, and decreasing fiber alignment as protein content increased in RJS hybrid fibers. RJS nanofiber constructs also demonstrate highly anisotropic mechanical properties mimicking several biological tissue types. We demonstrate the bio-functionality of RJS scaffold fibers by testing their ability to support cell growth and maturation with a variety of cell types. Our highly anisotropic RJS fibers are therefore able to support cellular alignment, maturation and self-organization. The hybrid nanofiber constructs fabricated by RJS therefore have the potential to be used as scaffold material for a wide variety of biological tissues and organs, as an alternative to electrospinning.  相似文献   
96.
97.
Vasospasm of the cerebrovasculature is a common manifestation of blast-induced traumatic brain injury (bTBI) reported among combat casualties in the conflicts in Afghanistan and Iraq. Cerebral vasospasm occurs more frequently, and with earlier onset, in bTBI patients than in patients with other TBI injury modes, such as blunt force trauma. Though vasospasm is usually associated with the presence of subarachnoid hemorrhage (SAH), SAH is not required for vasospasm in bTBI, which suggests that the unique mechanics of blast injury could potentiate vasospasm onset, accounting for the increased incidence. Here, using theoretical and in vitro models, we show that a single rapid mechanical insult can induce vascular hypercontractility and remodeling, indicative of vasospasm initiation. We employed high-velocity stretching of engineered arterial lamellae to simulate the mechanical forces of a blast pulse on the vasculature. An hour after a simulated blast, injured tissues displayed altered intracellular calcium dynamics leading to hypersensitivity to contractile stimulus with endothelin-1. One day after simulated blast, tissues exhibited blast force dependent prolonged hypercontraction and vascular smooth muscle phenotype switching, indicative of remodeling. These results suggest that an acute, blast-like injury is sufficient to induce a hypercontraction-induced genetic switch that potentiates vascular remodeling, and cerebral vasospasm, in bTBI patients.  相似文献   
98.
99.

Objective

This study evaluated the effects of Kaltenborn manual therapy on sensory and motor function in elderly patients with secondary carpometacarpal osteoarthritis (CMC OA).

Method

Twenty-nine female patients with secondary CMC OA (70-90 years old) were randomized into Kaltenborn manual therapy and sham groups. This study was designed as a double-blind, randomized controlled trial (RCT). Therapy consisted of Kaltenborn mobilization of posterior-anterior gliding with distraction in grade 3 of the carpometacarpal (CMC) joint of the dominant hand during 6 sessions over 2 weeks. Pain was measured by algometry, as the pressure pain threshold (PPT) at the CMC joint and tubercle of the scaphoid bone. The tip and tripod pinch strength was also measured. Grip strength was measured by a grip dynamometer. Measurements were taken before treatment and after 1 week (first follow-up [FU]) and 2 weeks (second FU).

Results

All values in the sham group remained unchanged during the treatment period. In the treated group, the PPT in the CMC joint was 2.98 ± 0.30 kg/cm2, which increased after treatment to 4.07 ± 0.53, and was maintained at the same level during the first FU (3.46 ± 0.31) and second FU (3.84 ± 0.36). Similarly, the PPT in the scaphoid bone was 3.61 ± 0.29 kg/cm2, which increased after treatment to 4.87 ± 0.37, and was maintained at the same level during the first FU (4.44 ± 0.43) and second FU (4.22 ± 0.32). In contrast, we found no differences in the tip, tripod pinch, and grip strength measurements between the treatment and sham groups.

Conclusions

This study showed that Kaltenborn manual therapy decreased pain in the CMC joint and scaphoid bone areas of elderly female patients; however, it did not confer an increase in motor function in patients with CMC OA.  相似文献   
100.
PURPOSE: To investigate the motion characteristics of distal esophagus cancer primary tumors using four-dimensional computed tomography (4D CT). METHODS AND MATERIALS: Thirty-one consecutive patients treated for esophagus cancer who received respiratory-gated 4D CT imaging for treatment planning were selected. Deformable image registration was used to map the full expiratory motion gross tumor volume (GTV) to the full-inspiratory CT image, allowing quantitative assessment of each voxel's displacement. These displacements were correlated with patient tumor and respiratory characteristics. RESULTS: The mean (SE) tidal volume was 608 (73) mL. The mean GTV volume was 64.3 (10.7) mL on expiration and 64.1 (10.7) mL on inspiration (no significant difference). The mean tumor motion in the x-direction was 0.13 (0.006) cm (average of absolute values), in the y-direction 0.23 (0.01) cm (anteriorly), and in the z-direction 0.71 (0.02) cm (inferiorly). Tumor motion correlated with tidal volume. Comparison of tumor motion above vs. below the diaphragm was significant for the average net displacement (p = 0.014), motion below the diaphragm was greater than above. From the cumulative distribution 95% of the tumors moved less than 0.80 cm radially and 1.75 cm inferiorly. CONCLUSIONS: Primary esophagus tumor motion was evaluated with 4D CT. According to the results of this study, when 4D CT is not available, a radial margin of 0.8 cm and axial margin of +/-1.8 cm would provide tumor motion coverage for 95% of the cases in our study population.  相似文献   
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