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Background
The telomeric region of mouse chromosome 12 has previously shown frequent allelic loss in murine lymphoma. The Bcl11b gene has been identified and suggested as a candidate tumor suppressor gene within this region. In this study, we aimed to elucidate whether Bcl11b is mutated in lymphomas with allelic loss, and whether the mutations we detected conferred any effect on cell proliferation and apoptosis. 相似文献3.
4.
R. Jerre J. Karlsson B. Romanus J. Wallin 《Archives of orthopaedic and trauma surgery》1997,116(6-7):348-351
All 170 patients (212 hips) treated between 1946 and 1992 for slipped capital femoral epiphysis (SCFE) with fixation in situ with a single device were reviewed to evaluate the incidence of further slipping of the epiphysis after primary treatment. In 154 hips, a smooth device without anchorage in the epiphysis was used and in 58, a device anchored in the epiphysis. In 3 hips, further slipping of the epiphysis occurred after primary treatment with no obvious cause. In 10 hips, an obvious cause for further slipping of the epiphysis was found. These 10 hips were re-operated due to the loss of epiphyseal grip in 6 hips, unsatisfactory placement of the device in 1, while in the remaining 3 hips, the device was removed before physeal closure. Twenty-six hips (12.3%) were re-operated because the device had lost its epiphyseal grip before physeal closure, and in 25 of these hips the device was smooth and had no anchorage in the epiphysis. The conclusion of this study is that a single device with anchorage in the epiphysis is stable enough to prevent further slipping of the epiphysis in hips with SCFE. 相似文献
5.
Gunilla Movin-Osswald Per Karlsson Margareta Hammarlund-Udenaes Lars Farde 《Psychopharmacology》1994,114(2):248-256
The D2-dopamine receptor antagonist raclopride was administered to eight healthy male subjects, who had previously experienced akathisia following antipsychotic drugs. The influence of administration rate on onset, severity and duration of akathisia and on prolactin response was studied. Raclopride 3,5 or 9 mg or placebo (P) was administered as single IV infusions during 10 min (R10 min/3 mg), 1 h (R1h/5 mg) or 4 h (R4h/9 mg) according to a randomized double-blind design. Despite a 24-fold difference in administration rate a similar peak raclopride concentration of about 350 nmol/l was obtained after all three infusions. Three of the eight subjects experienced akathisia following R10 min/3 mg and R1h/5 mg, respectively. After R4h/9 mg seven subjects experienced akathisia of longer duration but not more severe than after the short infusions. The incidence and duration of akathisia seem to be mainly related to the plasma raclopride concentrations over time, whereas the rate of administration might be more important for the severity. A maximal prolactin response was induced which was not markedly affected by the rate of administration. 相似文献
6.
Substance P and human nasal mucociliary activity 总被引:2,自引:0,他引:2
Summary Substance P (SP), a potent inflammatory agent, has been found in sensory nerve fibres in the nasal mucosa in several experimental animals as well as in man. It may participate in the inflammatory response as part of the mucosal defence against foreign materials. In experimental animals SP has been found to increase mucociliary in airway mucosa. The present study was performed in order to find out the relationship between topically applied SP and nasal mucociliary function in humans. Thirteen healthy volunteers were challenged with 65 µg SP or placebo in a randomized cross over fashion and mucociliary transport time was determined each time using the saccharine dye test. The dose of SP was chosen after an open dose-response study. No statistically significant change in the mucociliary transport time was found after challenge with SP as compared to placebo. The possible reasons for this are discussed. 相似文献
7.
Self-report questionnaires completed by young adults with Type I diabetes were examined to determine if individuals differing in recent metabolic control (Poor, Moderate or Very Good) or disease duration (Long, Short) also vary in either occurrence or type of life events during the past year or occurrence of recent emotional distress. Subjects in Poor control reported more positive and neutral life events during the past year, suggesting even those life changes individuals view benignly may be associated with metabolic control difficulties. Individuals in Poor control also reported more recent symptoms of depression, anxiety and hostility than did individuals in Moderate or Very Good control--symptomatology which may further impair their ability to adhere to a complex self-care regimen. Individuals with Long disease duration reported more positive and negative recent life experiences than did subjects with Short disease duration, but did not evidence concomitant disruptions in metabolic control. The role experience with a chronic disease may play in this finding was unclear, however. Although more research is required to clarify the exact relation of psychosocial variables and diabetic control, these findings suggest that clinically relevant subgroup parameters, subjects' perceptions of life change, and demographic variables may be important factors to assess. 相似文献
8.
R Karlsson S Edén L Eriksson B von Schoultz 《Gynecologic and obstetric investigation》1992,34(4):197-201
The interpretation of previous data on osteocalcin during pregnancy has been complicated by the fact that serum levels, at least in nonpregnant women, display a significant circadian variation. In the present study, serum concentrations of osteocalcin were recorded for 24 h in 12 individual women. In 4 nonpregnant women, there were striking diurnal fluctuations during the sampling period, with values ranging from 0.5 to 4.0 ng/ml. One woman who was investigated in the 11th week of pregnancy showed similar fluctuations in osteocalcin concentrations whereas in the 15th and 17th week values were much lower with minor fluctuations. In 4 women investigated during late pregnancy (weeks 34-38), osteocalcin serum levels were extremely low (range 0.2-0.4 ng/ml), often below the detection limit of the assay, and there was no diurnal variation. Also, in 1 lactating woman, osteocalcin serum levels were low (0.3-0.8 ng/ml) and stable. Low osteocalcin values during pregnancy may indicate a reduced bone turnover possibly mediated via an altered estrogen and growth hormone secretion. 相似文献
9.
A marked proportion of primary care patients have mental disorders and problems that remain unrecognized by the patients and their general practitioners. There is furthermore a great variation in the physicians’ ability to detect mental disorders. The aim of the present study was to find out the overall prevalence of mental disorders among patients receiving primary health care. The material consisted of 1000 randomly selected adult patients attending primary care facilities in Turku. The mental disorders were assessed by using the Symptom Checklist (SCL-25) and by general practitioners. According to the SCL-25, one fourth of the sample had a mental disorder. Only two fifths of them could be identified by the general practitioners. 相似文献
10.
The effect of fraction time in intensity modulated radiotherapy: theoretical and experimental evaluation of an optimisation problem. 总被引:3,自引:0,他引:3
Xiangkui Mu Per-Olov L?froth Mikael Karlsson Bj?rn Zackrisson 《Radiotherapy and oncology》2003,68(2):181-187
BACKGROUND AND PURPOSE: In intensity modulated radiotherapy (IMRT), the complexity and the number of treatment fields have expanded. This may imply that the delivery time for each fraction becomes prolonged. In a number of IMRT techniques used in the clinic, the delivery time per fraction is usually 10-15 min, sometimes more than 15 min. In studies on human skin, prolonged delivery time is shown to cause significant reduction of radiation effects compared with acute irradiation. In this paper the effect of changes in fraction delivery time was studied by in vitro irradiation of mammalian cells. MATERIAL AND METHODS: Chinese hamster fibroblasts (V79-379-A) were used for simulating clinical situations. Most experiments were performed with 2Gy/fraction with 4-h intervals in 40-60 replicates. Each fraction was divided into different subfractions, simulating the delivery of a complicated treatment. The effect of changing the delivery time for each fraction was studied. Parameters for the cell survival curve and repair kinetics were determined experimentally. The same methods were also used for large fraction sizes (8Gy). The validity of the most widely used models in the literature, all derived from linear-quadratic formalism, were tested against the experimental results. RESULTS: The effect of prolonging the fraction time for 2-Gy fractions was underestimated by the biological models. The experiments showed that 10-min prolonged delivery time gave a ratio between surviving fractions at 2Gy (S-ratio) of 1.054 with a 95% confidence interval (CI) 1.030-1.080, while the models predicted 1.007 and 1.009. Extending the fraction time to 20 min gave an S-ratio of 1.063 with CI of 1.045-1.080, while the models predicted 1.012 and 1.014. For 8-Gy fractions, there was a good agreement between predications and experimental results. The ratio between surviving fractions at 8Gy is 1.370 with CI of 1.300-1.440, while the models predicated 1.37 and 1.35. CONCLUSIONS: The effect of prolonging fraction time at conventional dose/fraction is underestimated by biological models. Prolonging the fraction time will spare tissues with a fast DNA repair. There is a risk for sparing tumours. This should be considered when IMRT technique is implemented in the clinic. 相似文献