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A human O6-alkylguanine-DNA-alkyltransferase (ATase) cDNA-containing retrovirus was used to infect murine long-term primary bone marrow cultures. High levels of ATase expression were obtained, and colony- forming cells of the granulocyte-macrophage lineage from the cultures transduced with the human ATase retrovirus were three times more resistant to the alkylating agent, N-methyl-N-nitrosourea (MNU), than control cultures. Furthermore, expression of the human ATase protected long-term hematopoiesis, measured as the output of progenitor cells to the nonadherent fraction of the culture, against the cytotoxic effects of repeated exposures to MNU. These results clearly show that a human ATase cDNA-containing retrovirus can be used to infect long-term primary bone marrow cultures and that this attenuates their sensitivity to nitrosoureas.  相似文献   
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目的:探讨输尿管硬镜在尿路疾病治疗中的应用效果。方法:对1000例尿路结石、输尿管及尿道狭窄、输尿管息肉、梗阻、异物存留等患者,均以输尿管硬镜配合其他设备进行治疗。结果:肾内结石34例治愈率76.5%,输尿管结石、膀胱及尿道结石治愈率为94.5%~99.8%;泌尿道狭窄治愈率66.7%~75%;33例泌尿道异物取出率97%。结论:基层医院在尿路疾病治疗中,根据病变的不同部位,将输尿管硬镜灵活配合现有并不高档的设备,同样可以取得较好的微创手术效果。  相似文献   
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Summary. Although particular importance has been attributed to attention deficits in attention deficit hyperactivity disorder (ADHD), there is no consensus as to the exact nature of inattention in ADHD or which components of attention are affected. The present study was based on a neuropsychological model of attention and assessed various components of attention in 23 children with ADHD/predominantly hyperactive-impulsive type (ADHD-H), 32 children with ADHD/combined type (ADHD-C) and healthy children (N1 = 23 and N2 = 32). A computerized test battery consisting of reaction time tasks of low complexity was used for the assessment of attention (alertness task, vigilance task, divided attention task, visual scanning task, incompatibility task, test of crossmodal integration, flexibility task). In comparison to healthy participants, patient groups were impaired in measures of vigilance, divided attention, selective attention and flexibility but not in measures of alertness. Analysis of the test performance of patient groups revealed no differences between children with ADHD-H and children with ADHD-C. The results of the present study suggest that both children with ADHD-H and children with ADHD-C are seriously impaired in attentional functioning. Children with ADHD-H and children with ADHD-C produced comparable results in measures of attention.  相似文献   
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BackgroundAccording to current guidelines, patients with primary breast cancer and 1–3 lymph node metastases will in general be offered adjuvant chemotherapy.AimOur objective was to investigate the relationship between markers of proliferation and apoptosis with survival for patients subjected to adjuvant tamoxifen solely.Material and methodsTumour cytosol samples from 409 consecutive patients with operable oestrogen receptor positive BC, stage I–III and treated with tamoxifen for 2 or 5 years were assessed for levels of caspase-cleaved cytokeratin-18 (ccCK18), an indicator of apoptosis, by use of an ELISA assay. Data on S-phase fraction (SPF) were available for 370 patients. Survival analyses were performed according to levels of ccCK18 and SPF separately, as well as combined.ResultsA wide range of ccCK18 protein levels was found, median 9.97, range 0.0–87.3 pg/μgDNA. Increasing SPFs were significantly associated with a lower distant recurrence-free survival (DRFS) (p = 0.025) and breast cancer survival (BCS) (p = 0.046). In the group with low SPF (below mean), low amounts of ccCK/18 correlated with a shorter DRFS (p = 0.0028) and BCS (p = 0.0027). A Proliferation Index (PI); a quotient of ccCK18/SPF was constructed. Low PI (high ccCK18/SPF ratios) were significantly correlated with an improved survival both when analysed as continuous variables; DRFS (p = 0.021), BCS (p = 0.038) and when divided into quartiles; DRFS (p < 0.001) and BCS (p = 0.0012). A similar correlation was found in patients with 1–3 lymph node metastases; DRFS (p = 0.089) and BCS (p = 0.019). A Cox's proportional hazard model including age, tumour size, lymph node status, PgR and ccCK18/SPF was used for multivariate analysis. High ccCK18/SPF ratios correlated with improved survival; DRFS (HR = 0.47 (0.22–0.98), p = 0.043), and BCS (HR = 0.39 (0.16–1.00), p = 0.049), respectively.ConclusionBy use of a proliferation index based on markers of proliferation and apoptosis, a group of patients with 1–3 lymph node metastases with good outcome following adjuvant tamoxifen was identified; this group could possibly be spared adjuvant chemotherapy.  相似文献   
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BACKGROUND: Our aims in the present study were to estimate the influences of pain and urinary symptoms on quality of life, and to determine which of these two variables has the most predictive power with respect to quality of life in young men with chronic prostatitis-like symptoms. METHODS: Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index. Of the 28,841 men aged 20 years who lived in the study community, 18,495 men (a response rate 64.1%) agreed to participate in the study. A total of 1057 men who complained of symptoms indicative of chronic prostatitis were included in the study. The influences of pain and urinary symptoms on quality of life were determined using logistic regression analysis. The receiver operating characteristic (ROC) curve was used to estimate the predictive ability of each of these variables with respect to quality of life. RESULTS: Results from multivariate analysis showed that both pain and urinary symptoms were associated with an increased likelihood of impaired quality of life, although pain contributed more to a reduced quality of life than urinary symptoms. Relative to men who experienced mild pain, men who experienced moderate pain had a 3.9-fold risk of poor quality of life (odds ratio [OR], 3.87; 95% confidence interval [CI], 2.86-5.23; P < 0.001) and those who experienced severe pain had a 15.7-fold risk of reduced quality of life (OR, 15.68; 95% CI, 6.59-37.35; P < 0.001). Moderate urinary symptoms were associated with a 1.4-fold risk of bother (OR, 1.41; 95% CI, 1.01-1.99; P < 0.001) and severe urinary symptoms were associated with 2.4-fold risk (OR, 2.39; 95% CI, 1.37-4.12; P < 0.001), relative to mild urinary symptoms. Comparison of the effects of pain and urinary symptoms showed that pain severity had the most predictive power for bother, quality of life, and quality-of-life impact. The areas under the ROC curves for bother, quality of life, and quality-of-life impact were 71.3%, 69.3% and 72.5%, respectively. CONCLUSION: Urinary symptoms and pain might be associated with an increased likelihood of impaired quality of life in young men with chronic prostatitis-like symptoms. In addition, our findings suggest that pain severity is the most influential variable for determining quality of life in this population.  相似文献   
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目的 观察颈中交感神经节阻滞治疗脑梗塞的临床效果。方法 将 6 4例脑梗塞患者按就诊次序随机分为两组 :(1)颈中交感神经阻滞组 (下简称阻滞组 ) :34例。 (2 )对照组 :30例。两组在脑梗塞常规用药上相同 ,阻滞组采用气管旁颈 6横突法 ,隔日阻滞 1次 ,共 6次。 2周后进行疗效评定。结果 阻滞组总有效率 (88 2 3 % )明显高于对照组 (6 0 % )。结论 颈中交感神经节阻滞是一种创伤较小的侵入性交感神经阻断技术 ,对缺血性脑血管病疗效确切  相似文献   
50.
Pediatric knee MR imaging: pattern of injuries in the immature skeleton   总被引:3,自引:0,他引:3  
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