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排序方式: 共有641条查询结果,搜索用时 562 毫秒
561.
562.
The computed tomographic (CT) angiograms of 44 patients who were being evaluated for possible hepatic surgery were studied. All patients were imaged with CT arterial portography (CTAP), delayed CT of the liver, and magnetic resonance (MR) imaging. All CTAP studies were evaluated for a "straight line," a linear variation in contrast within the liver. Sixteen patients (36%) demonstrated the straight line sign. All 16 had a mass at the proximal portion of the defect. Nine of 16 had defects that clearly correlated with portal venous distribution seen at limited digital angiography. Fourteen of the 16 patients showed loss of the straight line sign at delayed CT and/or MR imaging of the liver. These defects are thought to be due to vascular obstruction. The straight line sign will probably be seen more frequently as CTAP is more commonly used. Recognition of the sign is important in the evaluation of primary liver carcinomas, since it signifies that the tumor may be inoperable. Also, if metastatic disease is present, it alerts the surgeon to the proximity of the portal vein to the neoplasm. 相似文献
563.
SS LEUNG KS STEINBECK SL MORRIS MR KOHN SJ TOWNS DL BENNETT 《Journal of paediatrics and child health》1997,33(2):107-112
To describe the inter-relationship of chronic illness severity as perceived by adolescents with both psychosocial well-being and objective measures of illness severity. Additionally to compare the adolescents' perception of illness severity with how their physicians believe that the adolescents perceive their illness severity.
The psychological well-being of 48 adolescents with either cystic fibrosis (CF) or insulin-dependent diabetes mellitus (IDDM) was measured by four standardized questionnaires. The adolescents' perception of severity of illness was measured using an original instrument (PSCI), and this measure was compared to their physicians' estimates of how the adolescents perceived the severity of their illness and clinical illness.
There were 24 patients in both the CF and IDDM groups. Both groups were found to function well psychosocially; although, there were more patients with low self image compared to normative values. Depression and low self image were associated with a greater adolescent perception of illness severity. For both chronic illness groups, physicians' assessment of assumed adolescent perception of disease severity correlated with clinical indices of disease severity and was higher than the perception of illness severity reported by the adolescents. For adolescents with CF, but not with IDDM, perception of severity of chronic illness correlated with clinical indices.
For adolescents with chronic illness, their perception of illness severity is an important indicator of psychosocial well-being. Physicians do not accurately infer their patients' perception of illness severity. 相似文献
Methods:
The psychological well-being of 48 adolescents with either cystic fibrosis (CF) or insulin-dependent diabetes mellitus (IDDM) was measured by four standardized questionnaires. The adolescents' perception of severity of illness was measured using an original instrument (PSCI), and this measure was compared to their physicians' estimates of how the adolescents perceived the severity of their illness and clinical illness.
Results:
There were 24 patients in both the CF and IDDM groups. Both groups were found to function well psychosocially; although, there were more patients with low self image compared to normative values. Depression and low self image were associated with a greater adolescent perception of illness severity. For both chronic illness groups, physicians' assessment of assumed adolescent perception of disease severity correlated with clinical indices of disease severity and was higher than the perception of illness severity reported by the adolescents. For adolescents with CF, but not with IDDM, perception of severity of chronic illness correlated with clinical indices.
Conclusions:
For adolescents with chronic illness, their perception of illness severity is an important indicator of psychosocial well-being. Physicians do not accurately infer their patients' perception of illness severity. 相似文献
564.
Double-strand breaks may initiate the inversion mutation causing the Hunter syndrome 总被引:2,自引:2,他引:2
Lagerstedt K; Karsten SL; Carlberg BM; Kleijer WJ; Tonnesen T; Pettersson U; Bondeson ML 《Human molecular genetics》1997,6(4):627-633
We have previously shown that patients with the Hunter syndrome frequently
have suffered from a recombination event between the IDS gene and its
putative pseudogene, IDS-2, resulting in an inversion of the intervening
DNA. The inversion, which might be the consequence of an intrachromosomal
mispairing, is caused by homologous recombination between sequences located
in intron 7 of the IDS gene and sequences located distal of exon 3 in
IDS-2. In order to gain insight into the mechanisms causing the inversion,
we have isolated both inversion junctions in six unrelated patients. DNA
sequence analysis of the junctions showed that all recombinations have
taken place within a 1 kb region where the sequence identity is >98%. An
interesting finding was the identification of regions with alternating IDS
gene and IDS-2 sequences present at one inversion junction, suggesting that
the recombination event has been initiated by a double-strand break in
intron 7 of the IDS gene. The results from this study suggest that
homologous recombination in man could be explained by mechanisms similar to
those described for Saccharomyces cerevisiae. The results also have
practical implications for diagnosis of patients with the Hunter syndrome.
相似文献
565.
Serum vascular endothelial growth factor concentrations and ovarian stromal blood flow are increased in women with polycystic ovaries 总被引:4,自引:8,他引:4
Agrawal R; Sladkevicius P; Engmann L; Conway GS; Payne NN; Bekis J; Tan SL; Campbell S; Jacobs HS 《Human reproduction (Oxford, England)》1998,13(3):651-655
The aim of this study was to determine basal serum vascular endothelial
growth factor (VEGF) concentrations and Doppler blood flow changes within
the ovarian stroma of women with polycystic ovaries (PCO) and women with
normal ovaries. Pulsed and colour Doppler blood flows within the ovarian
stroma were recorded, and serum VEGF concentrations measured, in the early
follicular phase (days 2-3 of a menstrual cycle) in 60 women undergoing
ovarian stimulation for in-vitro fertilization. 36 women had normal
ovaries, 14 women had PCO as seen on pelvic ultrasound examination and 10
had polycystic ovarian syndrome (PCOS). Mean+/-SD serum VEGF concentrations
were significantly higher (P < 0.001) in women with PCO and PCOS
(3.4+/-0.7 and 3.2+/-0.66 ng/ml respectively) compared with women with
normal ovaries (2.3+/-0.5 ng/ml). Mean peak systolic blood flow velocity
(PSV) and time-averaged maximum flow velocity (TAMXV) were significantly
higher (P < 0.001) in women with PCO and PCOS compared with women with
normal ovaries. The mean PSV were 15+/-4 and 16+/-4 cm/s in women with PCO
and PCOS respectively, compared with 9+/-2 cm/s in women with normal
ovaries. The TAMXV were 9+/-3 and 11+/-3 cm/s in women with PCO and PCOS
respectively compared with women with normal ovaries (5.8+/-1.5 cm/s).
Serum VEGF concentrations were positively correlated with PSV (r=0.44,
P=0.001) and TAMXV (r=0.45, P < 0.000) in all three groups of women.
Higher serum concentrations of VEGF in women with PCO and PCOS may relate
to the increased vascularity that underlies the increased blood flow
demonstrated by Doppler blood flow velocity measurements in these women.
The results may explain the higher risk of ovarian hyperstimulation
syndrome in programmes of ovarian stimulation in patients with PCO compared
with those with normal ovaries.
相似文献
566.
根据天花粉蛋白(Tk)作用了淋巴细胞体外增殖的抑制是否由CD8细胞所介导,健康人群被分成介导型(M~+)和非介导型(M~-)两类。我们已有的工作证明,性状M~+/M~-由HLA连锁的一对孟德尔基因控制。本文采用分子生物学手段,对M~+”和M~-个体作HLAⅡ类基因的精细分型,发现编码DQ异二聚体分子的DQA和DQB两个基因同时决定M~+的表达,而且等位基因DQA1*0501和DQB1*0201以顺式和反式两种形式发挥互补作用,从而把人体中调控Tk免疫应答的遗传成份直接定位在该特定DQ分子的编码基因上。这一互补现象同时解释了DR3、DR5和DR7与M~+呈现次级关联的复杂格局。 相似文献
567.
568.
1临床资料妇科手术50例(枢丹组25例,氟哌啶组25例),年龄27~66岁,体质量47~84 kg,ASA Ⅰ,Ⅱ级.术前无恶心呕吐.术前24 h未用任何抗呕吐药.全部采用连续硬膜外阻滞L2-3椎间隙穿刺,使用1.33g/L利多卡因40.17g/L丁卡因(含0.05g/L肾上腺素),阻滞平面上界在T6.于麻醉阻滞平面完全,手术开始时枢丹8 mg,氟哌啶组iv氟哌啶2.5mg,注速均为0.5~1 min. 相似文献
569.
Thorpe C; Ryan B; McLean SL; Burt A; Stewart M; Brown JB; Reid GJ; Harris S 《Family practice》2009,26(1):65-68
This paper outlines ways to maximize response rates to surveysby summarizing the most relevant literature to date and demonstratinghow these techniques have resulted in consistently high ratesof return in family practice research. We describe the methodologyused in recent surveys of physicians conducted by the Centrefor Studies in Family Medicine through its Thames Valley FamilyPractice Research Unit, located in London, Ontario, Canada andfunded by the Ontario Ministry of Health and Long-Term Care.The identification and implementation of these techniques tomaximize response rates is critical, as primary health careresearchers often rely on information gathered through questionnairesto study physicians' practice profiles, experiences and attitudes.Four separate and distinct mailed surveys of physicians usinga modified Dillman approach were conducted from 2001 to 2004.The sampling strategies, topics, types of questions and responseformats of these surveys varied. The first survey did not useany incentives or recorded delivery/registered mail and receiveda response rate of 48%. In sharp contrast, the other three surveysobtained responses rates of 76%, 74%, 74%, respectively, achievedthrough the use of gift certificates and recorded delivery/registeredmail. Sending a survey by recorded delivery/registered mailtends to result in the survey package being given priority inthe physicians' incoming mail at the practice. Gift certificatespartially compensate physicians for time spent completing thesurvey and recognition of the time required is appreciated.The response rates achieved provide strong evidence to supportthe use of monetary incentives and recorded delivery/registeredmail (along with the Dillman approach) in survey research. Itis anticipated that this evidence will be used by other researchersto justify requests for funding to cover the costs associatedwith incentives and recorded delivery/registered mail. We recommendthe use of these strategies to maximize response rates and improvethe quality of this type of primary health care research. Keywords. Response rates, surveys, physicians. 相似文献
570.
William HC Li Joyce OK Chung Maureen ML Chui Polly SL Chan 《Journal of clinical nursing》2009,18(23):3253-3261
Aims. To evaluate the underlying factor structure of the Chinese version of General Health Questionnaire‐12 using exploratory and confirmatory factor analyses in Chinese adolescents and find out which factor model proposed by previous empirical research is the best‐fit model. Background. The 12‐item General Health Questionnaire has been extensively used with adolescents in the West. Yet, it has not been used with adolescents in a Hong Kong Chinese context. Design. A cross‐sectional study was employed. Method. Chinese students between the ages of 12–19 from four secondary schools were invited to participate in the study using the multiple‐stage stratified random sampling method during the period from December 2007–February, 2008. The total sample size included in the final analysed was 1883. Results. The General Health Questionnaire‐12 was found to be internally consistent. The results of exploratory factor analysis showed that there are two factors underlying the General Health Questionnaire‐12. Of nine factor models were tested by means of confirmatory factor analysis, only three factor model: the eight‐item two‐factor model, 12‐item three‐factor model and 10‐item two‐factor model, demonstrated good model fit across all model fit indices. Conclusion. This study addressed a gap in the literature by evaluating the factorial structure of the Chinese version of General Health Questionnaire‐12 using exploratory and confirmatory factor analyses in Chinese adolescents. The findings revealed that the eight‐item two‐factor model is the best‐fit model. Relevance to clinical practice. The adolescent mental health problem is alarming and aggravating and warrants special attention. It is essential for community nurses to differentiate psychological distress in adolescents and to identify those adolescents who are at a higher risk of suffering from mental health problems. The availability of a valid and reliable instrument that measures adolescents’ psychological distress is crucial before any nursing interventions to promote their mental health can be appropriately planned, implemented and evaluated. 相似文献