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排序方式: 共有671条查询结果,搜索用时 15 毫秒
81.
82.
Spinning top urethra (STU) is a term used to describe a widened posterior urethra seen mainly in girls. It is commonly regarded as a normal variant. The authors studied 30 girls with STU using videourodynamics. Twenty-eight showed bladder instability; 21, a congenital wide bladder neck anomaly; and 20, both instability and a wide bladder neck. One patient had a sensitive bladder. All patients had a urodynamic abnormality. The authors believe that the STU is nearly always an indication of bladder instability or wide bladder neck anomaly. The most common mechanism for the dilatation of the posterior urethra is that unstable contractions are resisted by a voluntary increase in distal sphincter tension so as to prevent leakage of urine. The resulting pressure rise produces distention of the posterior urethra, which will be maximal in subjects with a weak bladder neck mechanism as in the congenital wide bladder neck anomaly. The authors believe that STU is seldom if ever a normal variant. 相似文献
83.
The platelet release reaction was studied by a new quenched-flow approach. Platelets labeled with 14C-serotonin were reacted for short times (up to 5 sec) with thrombin and then quenched with glutaraldehyde or paraformaldehyde. Serotonin secretion began within 1 sec and was nearly complete by 4 sec. Aggregation recorded by a resistive-particle counter was similarly fast. Therefore, the quenched-flow system reveals that serotonin secretion can occur more rapidly than estimated in earlier studies. 相似文献
84.
Bronner MP Goldblum JR Kimmey MB Brentnall TA Rubin CE 《Gastroenterology》2004,127(1):362-3; author reply 363-4
85.
Rulyak SJ Mandelson MT Brentnall TA Rutter CM Wagner EH 《Gastrointestinal endoscopy》2004,59(2):239-247
BACKGROUND: Substantial variability in the use of colon surveillance among colorectal cancer survivors has been reported. This study sought to examine trends in the use of colon surveillance among patients who have had colorectal cancer and to investigate factors associated with utilization. METHODS: Health maintenance organization enrollees with a diagnosis of local or regional colon or rectal cancer between January 1993 and December 1999 were studied. Receipt of a colon examination by colonoscopy or by flexible sigmoidoscopy, together with barium contrast radiography of the colon was determined from automated clinical records, and rates of colon surveillance were estimated by using survival analysis. RESULTS: A total of 1002 patients with a diagnosis of colorectal cancer met inclusion criteria for the study. Colon examinations were performed in 61% of patients within 18 months of diagnosis and in 80% of patients within 5 years of diagnosis. The median time from diagnosis to first colon surveillance examination (14 months) was unchanged over the study period, but the interval between first and second surveillance examinations increased by 17 months (p<0.001). Patients over 80 years of age (relative risk=0.32; 95% CI[0.22, 0.45]) and those with rectal cancer (relative risk=0.80; 95% CI[0.66, 0.97]) were less likely to undergo surveillance. Higher socioeconomic status (relative risk=1.29; 95% CI[1.03, 1.61]) and being married (relative risk=1.27; 95% CI[1.05, 1.53]) were associated with greater utilization. There was lower utilization among African American patients (relative risk=0.70; p=0.14) and increased utilization among other minorities (relative risk=1.47; p=0.06). CONCLUSIONS: There is substantial variability in the use of colon examination for surveillance in patients with a history of colorectal cancer, and clinical and sociodemographic factors appear to influence the likelihood of surveillance. 相似文献
86.
Brentnall TA 《The American journal of gastroenterology》2011,106(5):955-956
The concept of pancreatic cancer prevention through surveillance of high-risk patients has come of age. It is cost-effective to provide surveillance of patients who have a lifetime risk of pancreatic cancer that is ≥16%. Studies are currently ongoing that contribute to our understanding of the imaging methodologies that are best suited for surveillance and the best algorithm for the clinical management of patients who are at risk of this highly lethal disease. Long-term outcomes analyses will help shed light on the best management of these patients, as well as a better understanding of the natural history of familial pancreatic cancer. 相似文献
87.
Andi Utama Sigit Purwantomo Marlinang Diarta Siburian Rama Dhenni Rino Alvani Gani Irsan Hasan Andri Sanityoso Upik Anderiani Miskad Fardah Akil Irawan Yusuf Wenny Astuti Achwan Soewignjo Soemohardjo Syafruddin AR Lelosutan Ruswhandi Martamala Benyamin Lukito Unggul Budihusodo Laurentius Adrianus Lesmana Ali Sulaiman Susan Tai 《World journal of gastroenterology : WJG》2009,15(32):4028-4036
AIM: To identify the distribution of hepatitis B virus (HBV) subgenotype and basal core promoter (BCP) mutations among patients with HBV-associated liver disease in Indonesia.
METHODS: Patients with chronic hepatitis (CH, n =61), liver cirrhosis (LC, n = 62), and hepatocellular carcinoma (HCC, n = 48) were included in this study. HBV subgenotype was identified based on S or preS gene sequence, and mutations in the HBx gene including the overlapping BCP region were examined by direct sequencing.
RESULTS: HBV genotype B (subgenotypes B2, B3, B4, 85 and B7) the major genotype in the samples, accounted for 75.4%, 71.0% and 75.0% of CH, LC and HCC patients, respectively, while the genotype C (subgenotypes C1, C2 and C3) was detected in 24.6%, 29.0%, and 25.0% of CH, LC, and HCC patients, respectively. Subgenotypes B3 (84.9%) and C1 (82.2%) were the main subgenotype in HBV genotype B and C, respectively. Serotype adw2 (84.9%) and adrq+ (89.4%) were the most prevalent in HBV genotype B and C, respectively. Double mutation (A1762T/G1764A) in the BCP was significantly higher in LC (59.7%) and HCC (54.2%) than in CH (19.7%), suggesting that this mutation was associated with severity of liver disease. The T1753V was also higher in LC (46.8%), but lower in HCC (22.9%) and CH (18.0%), suggesting that this mutation may be an indicator of cirrhosis.
CONCLUSION: HBV genotype B/B3 and C/C1 are the major genotypes in Indonesia. Mutations in BCP, such as A1762T/G1764A and T1753V, might have an association with manifestations of liver disease. 相似文献
METHODS: Patients with chronic hepatitis (CH, n =61), liver cirrhosis (LC, n = 62), and hepatocellular carcinoma (HCC, n = 48) were included in this study. HBV subgenotype was identified based on S or preS gene sequence, and mutations in the HBx gene including the overlapping BCP region were examined by direct sequencing.
RESULTS: HBV genotype B (subgenotypes B2, B3, B4, 85 and B7) the major genotype in the samples, accounted for 75.4%, 71.0% and 75.0% of CH, LC and HCC patients, respectively, while the genotype C (subgenotypes C1, C2 and C3) was detected in 24.6%, 29.0%, and 25.0% of CH, LC, and HCC patients, respectively. Subgenotypes B3 (84.9%) and C1 (82.2%) were the main subgenotype in HBV genotype B and C, respectively. Serotype adw2 (84.9%) and adrq+ (89.4%) were the most prevalent in HBV genotype B and C, respectively. Double mutation (A1762T/G1764A) in the BCP was significantly higher in LC (59.7%) and HCC (54.2%) than in CH (19.7%), suggesting that this mutation was associated with severity of liver disease. The T1753V was also higher in LC (46.8%), but lower in HCC (22.9%) and CH (18.0%), suggesting that this mutation may be an indicator of cirrhosis.
CONCLUSION: HBV genotype B/B3 and C/C1 are the major genotypes in Indonesia. Mutations in BCP, such as A1762T/G1764A and T1753V, might have an association with manifestations of liver disease. 相似文献
88.
G Zifarelli A Liantonio A Gradogna A Picollo G Gramegna M De Bellis AR Murgia E Babini D Conte Camerino M Pusch 《British journal of pharmacology》2010,160(7):1652-1661
Background and purpose:
ClC-K kidney Cl− channels are important for renal and inner ear transepithelial Cl− transport, and are potentially interesting pharmacological targets. They are modulated by niflumic acid (NFA), a non-steroidal anti-inflammatory drug, in a biphasic way: NFA activates ClC-Ka at low concentrations, but blocks the channel above ∼1 mM. We attempted to identify the amino acids involved in the activation of ClC-Ka by NFA.Experimental approach:
We used site-directed mutagenesis and two-electrode voltage clamp analysis of wild-type and mutant channels expressed in Xenopus oocytes. Guided by the crystal structure of a bacterial CLC homolog, we screened 97 ClC-Ka mutations for alterations of NFA effects.Key results:
Mutations of five residues significantly reduced the potentiating effect of NFA. Two of these (G167A and F213A) drastically altered general gating properties and are unlikely to be involved in NFA binding. The three remaining mutants (L155A, G345S and A349E) severely impaired or abolished NFA potentiation.Conclusions and implications:
The three key residues identified (L155, G345, A349) are localized in two different protein regions that, based on the crystal structure of bacterial CLC homologs, are expected to be exposed to the extracellular side of the channel, relatively close to each other, and are thus good candidates for being part of the potentiating NFA binding site. Alternatively, the protein region identified mediates conformational changes following NFA binding. Our results are an important step towards the development of ClC-Ka activators for treating Bartter syndrome types III and IV with residual channel activity. 相似文献89.
TG Bird L Boutler A Cole S Lorenzini WY Lu T Hay R Ridgway M Williams B Knight S Gordon Keylock D Wjotacha T Jamieson JP Iredale AR Clarke OJ Sansom SJ Forbes 《Lancet》2013
Insufficient regeneration of the adult liver is believed to cause failure to recover from severe liver disease. An undifferentiated cell population with stem-cell-like qualities known as hepatic progenitor cells (HPCs) is hypothesised to have a central role in regeneration of the adult liver during massive or chronic liver disease. Stem cells in other organ systems are believed to reside in a specialised microenvironment or niche that supports their maintenance and function. The existence of a hepatic stem cell niche might provide a means of therapeutically manipulating endogenous HPCs in vivo as a regenerative therapy.To investigate the physiological potential of HPCs to regenerate the mammalian liver, we have established a novel model of hepatocellular injury and HPC activation using genetic manipulation of hepatocytes. After hepatocyte senescence and death in this model (AhCre Mdm2flox), HPCs expand and bring about the complete regeneration of the liver parenchyma.We demonstrate that a stereotypical niche, consisting partly of macrophages, exists in both animal models and correlating human disease. Using cell tracking, we show active recruitment of extrahepatic macrophages into this niche during injury. In health, intravenous injection of macrophages results in macrophage engraftment to the liver niche, with subsequent HPC activation and changes to liver structure and function.Within the niche, macrophages use paracrine signalling to control both HPC proliferation and cell fate via TWEAK (tumour-necrosis-factor-like weak inducer of apoptosis) and the Wnt signalling pathway, respectively. After hepatocellular injury, macrophages ingest hepatocyte debris, and release Wnt which promotes HPC differentiation into hepatocytes. TWEAK is vital for HPC proliferation in the AhCre Mdm2flox model of regeneration. Here, the absence of TWEAK signalling results in liver failure and mortality.This work has demonstrated for the first time the ability of a solid organ to fully regenerate in the adult mammal from progenitor cells, and additionally highlights mechanisms by which this process can be modulated by either small molecule or cell therapy.FundingUniversity of Edinburgh. 相似文献
90.
R Alexander A Kerby AA Aubdool AR Power S Grover C Gentry AD Grant 《British journal of pharmacology》2013,168(3):761-772