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   84篇
  免费   2篇
  国内免费   9篇
耳鼻咽喉   3篇
儿科学   2篇
妇产科学   1篇
基础医学   11篇
临床医学   20篇
内科学   17篇
皮肤病学   1篇
神经病学   2篇
外科学   20篇
综合类   3篇
预防医学   2篇
眼科学   1篇
药学   6篇
中国医学   2篇
肿瘤学   4篇
  2021年   1篇
  2018年   1篇
  2017年   1篇
  2016年   2篇
  2015年   4篇
  2014年   3篇
  2013年   4篇
  2012年   12篇
  2011年   6篇
  2010年   7篇
  2009年   6篇
  2008年   12篇
  2007年   3篇
  2006年   8篇
  2005年   8篇
  2004年   9篇
  2003年   1篇
  2002年   3篇
  2000年   2篇
  1997年   1篇
  1989年   1篇
排序方式: 共有95条查询结果,搜索用时 31 毫秒
1.

Background:

Lung cancer has become the leading cause of death in many regions. Carcinogenesis is caused by the stepwise accumulation of genetic and chromosomal changes. The aim of this study was to investigate the chromosome and gene alterations in the human lung adenocarcinoma cell line OM.

Methods:

We used Giemsa banding and multiplex fluorescence in situ hybridization focusing on the human lung adenocarcinoma cell line OM to analyze its chromosome alterations. In addition, the gains and losses in the specific chromosome regions were identified by comparative genomic hybridization (CGH) and the amplifications of cancer-related genes were also detected by polymerase chain reaction (PCR).

Results:

We identified a large number of chromosomal numerical alterations on all chromosomes except chromosome X and 19. Chromosome 10 is the most frequently involved in translocations with six different interchromosomal translocations. CGH revealed the gains on chromosome regions of 3q25.3-28, 5p13, 12q22-23.24, and the losses on 3p25-26, 6p25, 6q26-27, 7q34-36, 8p22-23, 9p21-24, 10q25-26.3, 12p13.31-13.33 and 17p13.1-13.3. And PCR showed the amplification of genes: Membrane metalloendopeptidase (MME), sucrase-isomaltase (SI), butyrylcholinesterase (BCHE), and kininogen (KNG).

Conclusions:

The lung adenocarcinoma cell line OM exhibited multiple complex karyotypes, and chromosome 10 was frequently involved in chromosomal translocation, which may play key roles in tumorigenesis. We speculated that the oncogenes may be located at 3q25.3-28, 5p13, 12q22-23.24, while tumor suppressor genes may exist in 3p25-26, 6p25, 6q26-27, 7q34-36, 8p22-23, 9p21-24, 10q25-26.3, 12p13.31-13.33, and 17p13.1-13.3. Moreover, at least four genes (MME, SI, BCHE, and KNG) may be involved in the human lung adenocarcinoma cell line OM.  相似文献   
2.
We investigated the age-related bone mineral density (BMD), accumulated bone loss rate (ABLR) and the prevalence of osteoporosis at different skeletal sites in Chinese women. BMD was measured at the anteroposterior (AP) spine, supine lateral spine (areal BMD at the midarea [mLat] and the whole region [Lat], volumetric BMD at the middle region [MVD] and total region [TVD]), hip (femoral neck [FN], trochanter [Troc] and Ward’s triangle [Ward’s]) and forearm (radius + ulna ultradistal [RUUD], 1/3 region [RU1/3] and total region [RUT]) using a dual-energy X-ray absorptiometry (DXA) fan-beam bone densitometer (Hologic QDR 4500A) in 2702 females aged from 5 to 96 years old. Data were analyzed by eight different regression models. We found that the cubic regression model was the best for describing age-related changes in BMD. The coefficients of determination (R 2) of the fitting curve were 0.398 to 0.612 (p= 0.000). The data were then analyzed by 5-year age groups. This showed that the earliest peak BMD was at the age of 20–24 years at Troc and Ward’s, and the latest at the age of 40–44 years at RU1/3 and RUT of the distal forearm. Compared with BMD, the ABLRs were highest at Ward’s (−66.2%) and the lowest at RU1/3 of the distal forearm (−31.3%) in subjects over 80 years old. The prevalence of osteoporosis at at least one site in these women was 0.5 ± 0.4% in those 30–39, 4.6 ± 4.4% in those 40–49, 23.9 ± 13.3% in those 50–59, 56.3 ± 20.3% in those 60–69, 71.8 ± 16.7% in those 70–79 and 83.2 ± 12.1% those over 80 years of age, respectively. The prevalence of osteoporosis in these women was 8.6–11.1% at the age of 40–49 and 36.5–40.6% at the age of 50–59 at the lateral spine regions (mLat, Lat, MVD and TVD), and 0.5–3.7% at the age of 40–49 and and 3.9–21.7% at the age of 50–59 years at the other skeletal sites (AP, FN, Troc, Ward’s, RUUD, RU1/3 and RUT). Significant differences were found in the prevalence of osteoporosis between the lateral spine regions and other skeletal sites (p<0.001) at the age of 40–59 years. In summary, we demonstrated significant age-related differences in peak BMD, ABLR and osteoporosis prevalence among various skeletal sites. Our data suggest that the supine lateral spine is the most sensitive site for the diagnosis of osteoporosis, especially in the early menopausal period, although the prevalence of osteoporosis varied with age and with different sites measured. Received: 20 November 2001 / Accepted: 13 February 2002  相似文献   
3.
To understand the effects of skeletal size of the lumbar spine on areal bone mineral density (aBMD), volumetric bone mineral density (vBMD), and the diagnosis of osteoporosis in postmenopausal women, we measured the projected bone area, bone mineral content (BMC), aBMD, and vBMD at the anteroposterior and lateral lumbar spines in a population of 1081 postmenopausal Chinese women, 42 to 86 years of age. The results indicated that, at the anteroposterior and lateral lumbar spine, there were significant positive correlations between bone area and both BMC (r = 0.606; P = 0.000 and r = 0.610; P = 0.000) and aBMD (r = 0.270; P = 0.000 and r = 0.182; P = 0.000), but not vBMD (r = –0.055; P = 0.000 and r = 0.000; P = 0.929). When bone area at the anteroposterior spine changed by ±1 SD, the BMC, aBMD, and vBMD correspondingly changed by 28.2%, 10.1%, and 1.69% on the basis of their respective means. When a variation of ±1 SD was observed in bone area at the lateral spine, BMC and aBMD, correspondingly changed by 25.9% and 6.18% on the basis of their respective means, while vBMD indicated no change. Through comparisons among large-, intermediate-, and small-bone area groups, significant differences were found in the means of subjects heights, weights, BMC, and vBMD at the anteroposterior and lateral lumbar spines, as well as in the detection rates of osteoporosis by aBMD (P = 0.000). Detection rates of osteoporosis by aBMD at the anteroposterior spine and by aBMD at the lateral spine, and by vBMD were 44.1%, 55.5%, and 49.7%, respectively, in the total population; 31.4%, 41.7%, and 53.7%, respectively, in the large-bone area group; 43.3%, 55.9%, and 50.5%, respectively, in the intermediate-bone area group; and 61.7%, 70.0%, and 42.5%, respectively, in the small-bone area group. No significant differences were found in the detection rates of osteoporosis by vBMD among the groups. The results of multiple linear regression revealed that the major factors influencing skeletal size and aBMD of the lumbar spine were height and weight. Therefore, in menopausal women of the same ethnic group and age, the skeletal size of the lumbar spine would have significant influence upon aBMD and the diagnosis of osteoporosis, i.e., the larger the spinal size, the greater the aBMD and the lower the osteoporosis detection rate, while, conversely, the smaller the skeletal size, the smaller the aBMD and the higher the osteoporosis detection rate. When we use aBMD of the lumbar spine to diagnose osteoporosis in a population with different body sizes, we need to take this body size difference into account. When we use vBMD to diagnose osteoporosis, the effect of body size on BMD will diminish.  相似文献   
4.
 This study was designed to establish Bone Mineral Density (BMD) Reference Databases for multiple skeletal sites appropriate for the diagnosis and evaluation of osteoporosis (OP) in Chinese women. We recruited 2702 healthy Chinese women, 5–96 years of age, for BMD assessment. BMD values at multiple skeletal sites including anteroposterior (AP) and lateral (Lat) lumbar spine, hip, and forearm were measured by dual-energy X-ray absorptiometry (DXA) using a QDR 4500A device; results were analyzed according to age group using eight regression models. BMD Reference Databases (CWD) were established according to the best regression equation and compared with Hologic reference databases for “Oriental Women” (OWD). Results indicated that the cubic regression model was superior to the quadratic, linear, logarithmic, and exponential regression models, etc. for our purpose, with a determinate coefficient (R 2) of 0.363–0.650 (P = 0.000). We included 1636 female patients, aged 35–86 years, in our tests. In comparison with Hologic Reference Databases, the mean detection rate of OP in the newly established BMD Reference Databases for Chinese Women (CWD) was 16.0% ± 2.68% lower (range, 13.7%–20.5%) at the AP spine, 16.8% ± 11.0% lower (range, 3.5%–32.8%) at the Lat spine (except for L4), 18.7% ± 4.6% lower (range, 12.6%–24.2%) at the hip, and 14.3% ± 6.9% higher (range, 4.7%–24.3%) at the forearm. The difference in detection rates for OP was significant between the two reference databases (P = 0.000), which was consistent with the differences in peak BMD values and the biological variability between them. Based upon our data, we confirmed that the Hologic BMD Reference Databases for Oriental Women (OWD) were not suitable for the diagnosis of OP in Chinese women; the BMD Reference Databases for Chinese Women (CWD) established in this study would provide reliable diagnostic standards for detection of OP in the women of South China. Received: July 9, 2002 / Accepted: December 5, 2002 Offprint requests to: X.-P. Wu  相似文献   
5.
6.
艰难梭菌(Clostridium difficile,CD)是一种G+厌氧芽胞粗大杆菌,是人和动物肠道中的正常菌群,可引起机会性感染,出现CD相关性腹泻、CD相关性肠炎等肠道疾病,在国内外出现过大规模流行,是全球面临的公共健康问题.CD的主要致病毒素是A毒素、B毒素和近年来新发现的二元毒素(CDT毒素),对于其防治可采用合理的护理措施和采用新型抗菌药物、CD疫苗、中药复方、微生态制剂等进行临床治疗.  相似文献   
7.
Combination of low doses of histone deacetylases inhibitors and chemotherapy drugs is considered as one of the most promising strategies to increase the anticancer efficacy. Chidamide is a novel benzamide chemical class of HDAC inhibitor that selectively inhibited HDAC1, 2, 3 and 10. We sought to determine whether chidamide may enhance platinum-induced cytotoxicity in NSCLC cells. In this study, the combination of chidamide with carboplatin showed a good synergism on growth inhibition with the mean combination index value as 0.712 and 0.639 in A549 and NCI-H157 cells, respectively. The used concentration of chidamide was non-toxic on cells by itself as low as 0.3 μM. All of our experiments were comparisons between combination regimen and single carboplatin regimen in A549 and NCI-H157 cell lines. Phosphorylated histone H2A.X (γH2A.X), a hall marker of DNA damage response, was dramatically increased by the combination treatment. Cell cycle analysis by flow cytometry and phosphorylation level analysis of histone H3 (Ser10) by western blotting showed that combination treatment significantly increased the percentage of G2/M phase of cells. Mitochondrial membrane potential and cleaved-PARP1 level analysis indicate that chidamide synergistically enhances carboplatin-induced apoptosis. Additionally, synergistic effects of chidamide were found when it was combined with two other platinum drugs (cisplatin and oxaliplatin). The results suggest that Chidamide in combination with platinum drugs may be a novel therapeutic option for NSCLC.  相似文献   
8.
Our study indicates that recombinant adiponectin induced RANKL and inhibited OPG expression in human osteoblasts through the AdipoR1/p38 MAPK pathway, and these responses contributed to the adiponectin-induced osteoclasts formation in the co-culture of osteoblast and peripheral blood monocytes systems. These findings showed that adiponectin increased osteoclast formation indirectly through stimulating RANKL and inhibiting OPG production in osteoblasts. It also suggests the pharmacological nature of recombinant adiponectin that indirectly induces osteoclasts formation. INTRODUCTION: Recently, adiponectin has emerged as an element in the regulation of bone metabolism, but the mechanism remains. This study was undertaken to investigate the action of adiponectin on osteoclastogenesis through revealing RANKL and osteoprotegerin (OPG) expression in osteoblasts and osteoclast formation. MATERIALS AND METHODS: Real-time quantitative PCR and ELISA were used to detect RANKL and OPG mRNA and protein expression in cultured human osteoblasts. The involved signal pathway was studied using mitogen-activated protein kinase (MAPK) inhibitor and adiponectin receptor 1 (AdipoR1) siRNA. The effects of recombinant adiponectin on osteoclasts formation also were examined in the co-culture systems of osteoblast and peripheral blood monocytes (PBMCs) systems or purified CD14 + PBMCs cultures. RESULTS: Our study showed that recombinant adiponectin induced RANKL and inhibited OPG mRNA expression in human osteoblasts in a dose- and time-dependent manner. Adiponectin also increased soluble RANKL and decreased OPG secretion in osteoblasts conditioned media. Suppression of AdipoR1 with siRNA abolished the adiponectin-regulated RANKL and OPG mRNA expression in osteoblasts. Furthermore, pretreatment of osteoblasts with the MAPK inhibitor SB203580 abolished adiponectin-regulated RANKL and OPG mRNA expression. Adiponectin induced osteoclast formation in the co-culture systems of osteoblast and PBMCs systems, and OPG entirely blocked this response. However, adiponectin had no direct effect on the differentiation of osteoclast precursor purified CD14 + PBMCs. CONCLUSIONS: These data indicate that recombinant adiponectin induced RANKL and inhibited OPG expression in human osteoblasts through the AdipoR1/p38 MAPK pathway, and these responses contributed to the adiponectin-induced osteoclast formation in the co-culture of osteoblast and PBMCs systems. These findings showed that adiponectin increased osteoclast formation indirectly through stimulating RANKL and inhibiting OPG production in osteoblasts. It suggests the pharmacological nature of recombinant adiponectin that indirectly induces osteoclasts formation.  相似文献   
9.
1. The aim of this study was to investigate the capacity of chiglitazar to improve insulin resistance and dyslipidemia in monosodium L-glutamate (MSG) obese rats and to determine whether its lipid-lowering effect is mediated through its activation of PPARalpha. 2. Chiglitazar is a PPARalpha/gamma dual agonist. 3. The compound improved impaired insulin and glucose tolerance; decreased plasma insulin level and increased the insulin sensitivity index and decreased HOMA index. Euglycemic hyperinsulinemic clamp studies showed chiglitazar increased the glucose infusion rate in MSG obese rats. 4. Chiglitazar inhibited alanine gluconeogenesis, lowered the hepatic glycogen level in MSG obese rats. Like rosiglitazone, chiglitazar promoted the differentiation of adipocytes and decreased the maximal diameter of adipocytes. In addition, chiglitazar decreased the fibrosis and lipid accumulation in the islets and increased the size of islets. 5. Chiglitazar reduced plasma triglyceride, total cholesterol (TCHO), nonesterified fatty acids (NEFA) and low density lipoprotein-cholesterol levels; lowered hepatic triglyceride and TCHO contents; decreased muscular NEFA level. Unlike rosiglitazone, chiglitazar showed significant increase of mRNA expression of PPARalpha, CPT1, BIFEZ, ACO and CYP4A10 in the liver of MSG obese rats. 6. These data suggest that PPARalpha/gamma coagonist, such as chiglitazar, affect lipid homeostasis with different mechanisms from rosiglitazone, chiglitazar may have better effects on lipid homeostasis in diabetic patients than selective PPARgamma agonists.  相似文献   
10.
Measurements of bone biochemical markers are increasingly being used to evaluate the state of bone turnover in the management of bone metabolic diseases, especially osteoporosis. However, changes in the bone turnover rate vary with age. The aim of this study was to establish the laboratory reference range of serum bone-specific alkaline phosphatase (sBAP), serum type I collagen cross-linked C-terminal telopeptide (sCTx), and urine CTx (uCTx), based on values from 665 healthy Chinese women aged 20–80 years. We measured the levels of sBAP, sCTx, serum alkaline phosphatase (sALP), and uCTx and evaluated the age-related changes and their relationship with bone mineral density (BMD) in the anteroposterior (AP) lumbar spine, hip, and left forearm. We found significant correlations between biochemical markers and age, with coefficients of determination (R 2) of 0.358 for sBAP, 0.126 for sCTx, 0.125 for uCTx, and 0.336 for sALP. The net changes in different biochemical markers were inversely correlated with the rates of BMD loss in the AP lumbar spine. After correction for age, body weight, and height, the levels of the markers had significant negative correlations with the BMD of the AP lumbar spine, femoral neck, and ultradistal forearm. All four biochemical markers had the highest negative correlation with BMD of the AP lumbar spine (partial correlation coefficients of −0.366, −0.296, −0.290, and −0.258 for sBAP, sCTx, uCTx, and sALP, respectively). The mean and SD values of these markers in premenopausal and postmenopausal women with normal BMD values were used as the normal reference ranges. The reference ranges of sBAP, sCTx, and uCTx for pre- vs postmenopausal women were 17.3 ± 6.23 vs 18.9 ± 7.52 U/l, 3.18 ± 1.49 vs 3.23 ± 1.57 nmol/l, and 15.5 ± 11.4 vs 16.2 ± 12.4 nM bone collagen equivalents/mM urinary creatinine, respectively. Levels of the bone formation marker (sBAP) and bone resorption markers (sCTx, uCTx) increased rapidly in women with osteopenia or osteoporosis, indicating that they may be sensitive markers to determine the bone turnover rate in healthy Chinese women.  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