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81.
Telomerase in relation to clinicopathologic prognostic factors and survival in cervical cancer 总被引:9,自引:0,他引:9
Wisman GB Knol AJ Helder MN Krans M de Vries EG Hollema H de Jong S van der Zee AG 《International journal of cancer. Journal international du cancer》2001,91(5):658-664
We investigated, in cervical cancer, the relation between telomerase activity, telomerase RNA (hTR) and mRNA of the catalytic subunit of telomerase, hTERT, with "classic" clinicopathological factors as well as survival. Frozen specimens were obtained from 107 consecutive patients with cervical cancer, treated with surgery or radiotherapy with or without chemotherapy. Telomerase activity was determined with fluorescence-based TRAP and hTR and hTERT with semi-quantitative RT-PCR. Eight normal cervical specimens served as controls. Analysis of prognostic factors and survival was limited to early-stage patients, treated primarily with radical hysterectomy. Telomerase activity was not detected in normal cervices and was present in 85 of 107 (79%) cervical cancers (p < 0.001). hTR was detected in all normal cervices and cervical cancers, while hTERT mRNA was detected in 1 of 8 (13%) normal cervices and in 83 of 104 (80%) cervical cancers (p < 0.001). In contrast to semi-quantitative hTR expression levels, semi-quantitative hTERT mRNA levels were related to telomerase activity levels (p < 0.01). In all patients, telomerase activity levels were related to differentiation grade (p < 0.05) but not to stage and histotype. In early-stage patients, telomerase activity, hTR and hTERT were not related to tumor volume, vascular invasion or presence of metastatic lymph nodes. Tumor volume, vascular invasion and presence of metastatic lymph nodes were related to (progression-free) survival, while telomerase activity and its subunits were not. Frequent up-regulation of telomerase activity and hTERT mRNA is especially observed in cervical cancers, while hTR is also detected in normal cervices. Telomerase is not applicable as a prognostic factor in early-stage cervical cancer patients. 相似文献
82.
83.
Henrica C. W. de Vet Raymond W. J. G. Ostelo Caroline B. Terwee Nicole van der Roer Dirk L. Knol Heleen Beckerman Maarten Boers Lex M. Bouter 《Quality of life research》2007,16(1):131-142
Background: Minimally important changes (MIC) in scores help interpret results from health status instruments. Various distribution-based
and anchor-based approaches have been proposed to assess MIC.
Objectives: To describe and apply a visual method, called the anchor-based MIC distribution method, which integrates both approaches.
Method: Using an anchor, patients are categorized as persons with an important improvement, an important deterioration, or without
important change. For these three groups the distribution of the change scores on the health status instrument are depicted
in a graph. We present two cut-off points for an MIC: the ROC cut-off point and the 95% limit cut-off point.
Results: We illustrate our anchor-based MIC distribution method determining the MIC for the Pain Intensity Numerical Rating Scale in patients with low back pain, using two conceivable
definitions of minimal important change on the anchor. The graph shows the distribution of the scores of the health status instrument for the relevant categories
on the anchor, and also the consequences of choosing the ROC cut-off point or the 95% limit cut-off point.
Discussion: The anchor-based MIC distribution method provides a general framework, applicable to all kind of anchors. This method forces researchers to choose and justify
their choice of an appropriate anchor and to define minimal importance on that anchor. The MIC is not an invariable characteristic of a measurement instrument, but may depend, among other things,
on the perspective from which minimal importance is considered and the baseline values on the measurement instrument under study. A balance needs to be struck between the
practicality of a single MIC value and the validity of a range of MIC values. 相似文献
84.
A patient with progressive osteolysis of the carpal and tarsal bones with glomerulonephritis of unusual severity is described. There was a notable absence of osteodystrophy in this and other reported cases who had chronic renal failure. 相似文献
85.
Li Qin Mirjam J. Knol Eva Corpeleijn Ronald P. Stolk 《European journal of epidemiology》2010,25(1):5-12
Obesity and physical inactivity are both risk factors for type 2 diabetes. Since they are strongly associated, it has been
suggested that they might interact. In this study, we summarized the evidence on this interaction by conducting a systematic
review. Two types of interaction have been discerned, statistical and biological interaction, which could give different results.
Therefore, we calculated both types of interaction for the studies in our review. Cohort studies, published between 1999 and
2008, that investigated the effects of obesity and physical activity on the risk of type 2 diabetes were included. We calculated
both biological and statistical interaction in these studies. Eight studies were included of which five were suitable to calculate
interaction. All studies showed positive biological interaction, meaning that the joint effect was more than the sum of the
individual effects. However, there was inconsistent statistical interaction; in some studies the joint effect was more than
the product of the individual effects, in other studies it was less. The results show that obesity and physical inactivity
interact on an additive scale. This means that prevention of either obesity or physical inactivity, not only reduces the risk
of diabetes by taking away the independent effect of this factor, but also by preventing the cases that were caused by the
interaction between both factors. Furthermore, this review clearly showed that results can differ depending on what method
is used to assess interaction. 相似文献
86.
A 10-year-old girl with cervical tuberculosis was treated with Isoniazid, Rimfampicin and Ethambutol. After 2 weeks of treatment a hepatotoxic reaction developed. Withdrawal of therapy resulted in complete clinical improvement and in normalization of all laboratory measurements. Treatment was restarted with Rifampicin, Pyrazinamid and Ethambutol. Liver enzyme levels were monitored weekly. Seven weeks after this three-drug regiment was started, all therapy was discontinued because of elevated liver enzyme levels. However, the patient died 2 weeks later of progressive fulminant hepatitis.Abbreviations TBC
tuberculosis
- INH
isoniazid
- RIF
Rifampicin
- EMB
Ethambutol
- GOT
glutamic oxaloacetic transaminase
- GPT
gammaglutamyl transpeptidase 相似文献
87.
Intensive group training protocol versus guideline physiotherapy for patients with chronic low back pain: a randomised controlled trial
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Nicole van der Roer Maurits van Tulder Johanna Barendse Dirk Knol Willem van Mechelen Henrica de Vet 《European spine journal》2008,17(9):1193-1200
Intensive group training using principles of graded activity has been proven to be effective in occupational care for workers with chronic low back pain. Objective of the study was to compare the effects of an intensive group training protocol aimed at returning to normal daily activities and guideline physiotherapy for primary care patients with non-specific chronic low back pain. The study was designed as pragmatic randomised controlled trial with a setup of 105 primary care physiotherapists in 49 practices and 114 patients with non-specific low back pain of more than 12 weeks duration participated in the study. In the intensive group training protocol exercise therapy, back school and operant-conditioning behavioural principles are combined. Patients were treated during 10 individual sessions along 20 group sessions. Usual care consisted of physiotherapy according to the Dutch guidelines for Low Back Pain. Main outcome measures were functional disability (Roland Morris disability questionnaire), pain intensity, perceived recovery and sick leave because of low back pain assessed at baseline and after 6, 13, 26 and 52 weeks. Both an intention-to-treat analysis and a per-protocol analysis were performed. Multilevel analysis did not show significant differences between both treatment groups on any outcome measures during the complete follow-up period, with one exception. After 26 weeks the protocol group showed more reduction in pain intensity than the guideline group, but this difference was absent after 52 weeks. We finally conclude that an intensive group training protocol was not more effective than usual physiotherapy for chronic low back pain. 相似文献
88.
Cystic fibrosis is the most common serious genetic disorder in people of European descent. Treatment of these patients is
ongoing throughout life and until now has been aimed at the consequences and is still not curative. Over the past 10–20 years,
there has been a dramatic improvement of mortality rates for cystic fibrosis, due in large part to advances in medical care.
The average age of survival for young people with cystic fibrosis is pushing well into the 20s with one third living into
their 30s. Consequently, education plays a major role in management of patients with cystic fibrosis, and starts directly
after being sure of the diagnosis. Growing up, these patients experience a lot of problems, and these are especially marked
in the adolescent. A special problem, for many cystic fibrosis patients is becoming an adult. Continuity in care for these
patients from the pediatric to the adult department is not always guaranteed.
It is concluded that patients with cystic fibrosis should be treated in specialized centers, and such treatment cannot be
carried out sufficiently by one person, but has to be embedded in a team of caregivers. 相似文献
89.
Micha Levi James A Knol William D Ensminger Susan J DeRemer Chunzhi Dou Susan M Lunte Heather S Bonner Leslie M Shaw David E Smith 《Drug metabolism and disposition》2002,30(12):1425-1430
Amifostine is a prodrug in which selectivity is largely determined by the preferential formation and uptake of its cytoprotective metabolite, WR-1065, in normal tissues as a result of differences in membrane-bound alkaline phosphatase activity. In this study, we characterized the sites and extent of organ-specific activation by the liver, gastrointestinal tract, lungs, and kidneys after systemic administrations of amifostine. A total of 10 dogs were infused via the cephalic vein using sequential dose rates of drug at 0.125, 0.500, and 1.00 micro mol/min/kg. Infusion of each dose rate lasted 2 h, at which time steady-state plasma concentrations were obtained (i.e., portal vein, carotid artery, hepatic vein, pulmonary artery, and renal vein). The hepatic arterial, portal venous, and renal arterial blood flows, and cardiac output, were measured. The hepatic and splanchnic extraction of amifostine remained high at 90%, whereas gastrointestinal extraction decreased from 43 to 12 to 15% with increasing dose. Pulmonary extraction of amifostine was low at 7%, whereas renal extraction was intermediate at 57%. Because blood flow measurements were relatively constant during the drug infusions, clearance parameters paralleled that of organ extraction. As a result, saturability was observed in the gastrointestinal blood clearance (i.e., from 9.8 to 2.8-3.3 ml/min/kg) and total body plasma clearance of amifostine (i.e., from 52.6 to about 37.3 ml/min/kg), as the doses increased. Due to the drug's high activation in liver, these findings suggest that amifostine may offer good protection of this organ against the toxicities of chemotherapy and radiation. 相似文献
90.
Transient synovitis of the hip in children: role of US 总被引:7,自引:0,他引:7
Marchal GJ; Van Holsbeeck MT; Raes M; Favril AA; Verbeken EE; Casteels- Vandaele M; Baert AL; Lauweryns JM 《Radiology》1987,162(3):825-828
Transient synovitis of the hip remains a common diagnostic problem for the clinician. The physical signs are not pathognomonic of the condition, and the classic technical examinations are of little help. Therefore, the authors retrospectively studied the value of hip arthrosonography in 46 children with clinical symptoms suggesting pathologic hip conditions. In 20 of the 21 patients with a final diagnosis of transient synovitis, articular effusion was detected on ultrasound (US). Conventional radiography showed an increased medial joint space in only eight of these patients. Increased echogenicity of the articular fluid was found in both transient synovitis and septic arthritis. The high sensitivity of US in detecting intraarticular fluid was demonstrated by cadaver studies. 相似文献