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1.
背景 致密性骨炎(OCI)和其他疾病有时难以鉴别,探讨血清骨转换生化标志物可为OCI的鉴别诊断提供依据。 目的 探索女性OCI患者的血清骨转换生化标志物的水平变化及临床意义。 方法 回顾性选取2013年6月至2022年2月在北京积水潭医院门诊及住院诊断为OCI的61例女性患者作为观察组,年龄15~50岁,平均(33.8±6.6)岁,病程2周~15年。选择同期61例女性体检健康者作为对照组,年龄15~48岁,平均(35.6±7.6)岁。比较两组一般临床资料和血清骨转换生化标志物水平,并对血清骨转换生化标志物与病情相关指标进行相关性分析。 结果 观察组血清白蛋白(45.4±2.9)g/L低于对照组(46.5±2.8)g/L(t=2.190,P<0.05)。血清骨转换生化标志物比较结果显示,观察组血清1型胶原羧基末端肽β特殊序列(β-CTX)〔0.28(0.23,0.37)μg/L〕、N-端骨钙素(OC)〔13.1(11.2,16.2)μg/L〕、25-羟维生素D3〔25-(OH)VD3〕〔(14.1±5.1)μg/L〕低于对照组〔0.36(0.29,0.48)μg/L,15.6(13.7,17.3)μg/L,(17.5±6.6)μg/L〕(Z=-2.983、-3.255,t=3.081,P<0.05)。长病程亚组OC水平〔14.6(12.4,18.5)μg/L〕高于短病程亚组〔11.7(10.2,14.0)μg/L〕(Z=-2.407,P<0.05)。多孕亚组β-CTX〔0.25(0.22,0.32)μg/L〕、OC水平〔12.2(10.3,15.0)μg/L〕低于非多孕亚组〔0.33(0.26,0.44)μg/L、13.4(12.0,18.8)μg/L〕(Z=-2.486、-1.897,P<0.05)。相关性分析显示,观察组血清1型前胶原氨基端延长肽(tP1NP)与妊娠次数、生产次数均呈负相关(rs=-0.276、-0.298,P<0.05),OC与体质指数(BMI)、视觉模拟评分法(VAS)评分、妊娠次数均呈负相关(rs=-0.284、-0.374、-0.360,P<0.05),25-(OH)VD3水平与BMI呈正相关(rs=0.275,P<0.05)。 结论 女性OCI患者血清OC、β-CTX水平明显降低,可为鉴别其他疾病提供依据;血清OC水平可以反映OCI患者的严重程度,同时OC水平与患者妊娠次数相关;tP1NP与妊娠次数、生产次数相关。  相似文献   
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Despite preventive efforts, HIV exposure is still a concern for public health. The current prevalence is related to unsafe sex, which is based on socio-cognitive variables. Therefore, information about these variables is required to verify whether the past preventive strategies have been effective and improve the future ones. However, there is not updated information to adjust future preventive interventions. For this reason, this study analyzes trends by gender in Spanish young people over the past two decades in perceived susceptibility to HIV, severity perceived to HIV, condom confidence and the intention of condom use, from 1999 to 2020. For this purpose, 11,665 Spanish young people (from 17 to 40 years old) completed the AIDS Prevention Questionnaire in each year. Following our results, in general, the socio-cognitive variables have revealed an unsatisfactory trend: a low perceived susceptibility to HIV and a behavioral intention that have remained stable or even declined slightly over the past years. Particularly, men are more likely to report a riskier level in socio-cognitive variables although, in the latest evaluations, women would decrease condom use intention largely than men. In general, regarding age, young adult would report better levels of condom confidence, but early youth would get higher results in perceived severity, as well as better scores in the latest evaluations of condom use intention. Considering these results, policies should make an effort in HIV prevention programs, and emphasize the attention to attitudinal beliefs and behavioral intention to improve their effectiveness.  相似文献   
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罗晓  何茜  李海冰  涂丽  张海玲  穆琼 《中国全科医学》2022,25(25):3184-3190
背景 我国基层全科医生的离职意愿较高,调查其离职意愿并分析影响因素,可以为减少基层卫生人才流失提供思路。目前,完成"5+3"模式(5年临床医学本科教育+3年住院医师规范化培训)培养的订单定向医学毕业生逐步履约进入基层工作,而针对该部分全科医生离职意向的研究相对较少。 目的 调查贵州省"5+3"模式订单定向医学毕业生回归基层工作后的离职意愿及影响因素,为完善吸引卫生人才留任、建设基层全科医生队伍相关政策提供依据。 方法 以贵州省截至2020年底已完成"5+3"模式培养并履约到基层医疗卫生机构工作的2015—2017级订单定向医学毕业生为研究对象。于2021-01-20至2021-02-10对其开展电子问卷调查,内容包括毕业生的一般情况、职业满意度、离职意愿、服务期满后职业方向。共回收问卷347份,其中有效问卷311份,问卷有效回收率为89.6%。采用单因素分析及多元逐步线性回归分析全科医生离职意愿的影响因素。 结果 贵州省"5+3"订单定向医学毕业生的整体离职意愿得分为(3.98±0.98)分,具有离职倾向者229例(73.6%)。不同性别、单位地理位置、每日工作量者的离职意愿得分比较,差异有统计学意义(P<0.05)。多元逐步线性回归分析显示,单位负责人对待下属的方式、在工作中获得的成就感、对当前收入满意程度、家人对工作的支持程度、当地激励政策执行程度是"5+3"订单定向医学毕业生离职意愿的影响因素(P<0.05)。服务期满后,计划留任原基层医疗卫生机构者12例(3.9%),计划去其他基层医疗卫生机构者21例(6.7%),计划离开基层去上级医院工作者196例(63.0%),计划攻读全日制硕士学位者60例(19.3%)。 结论 贵州省"5+3"模式订单定向医学毕业生的离职意愿较高,预计服务期满后基层全科人才流失较多,需从提高收入、重视全科医生心理需求、优化全科医生培养与使用、发展基层医疗卫生机构、加强全科宣传等方面着手改善。  相似文献   
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目的 观察高转换型肾性骨病中骨保护素及其配体 (OPG,RANKL)的表达,并与骨形态计量学指标进行相关分析。 方法 选择10例慢性肾衰尿毒症患者和3例正常人进行髂骨活检术,获得骨组织标本。采用免疫组化方法检测OPG和RANKL蛋白质的表达。采用全自动图像分析系统进行骨组织形态计量学测定。结果 10例慢性肾衰尿毒症患者经骨病理学检查证实均为高转换型骨病,以破骨细胞活化形成骨吸收陷窝伴或不伴骨矿化不全为特点。免疫组化显示尿毒症患者骨组织中以RANKL阳性表达为主。与正常对照相比,RANKL阳性表达细胞数目显著增加,OPG阳性表达细胞数目显著减少。尿毒症患者RANKL的阳性表达细胞数目与骨吸收面积和破骨细胞数目呈显著正相关。结论 高转换型肾性骨病中,PTH的溶骨作用可能是通过OPG/RANKL/RANK系统介导的。  相似文献   
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 In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly (PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML). Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive lesions extends previous experimental data on hematopoietic cell kinetics. Received: 10 March 1997 / Accepted: 18 May 1997  相似文献   
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The activation of membrane-associated phospholipase C is rapidly and transiently induced in the central nervous system by a variety of stimuli. Ischaemic brain injury is one of the situations that leads to a dramatic increase in polyphosphoinositide (PPI) turnover. In this study, stimulation of PPI hydrolysis by glutamate (500 μM) was measured in hippocampal slices from rats up to 21 days after an ischaemic insult of 30 min. Ischaemia was induced using the four-vessel occlusion method. PPI hydrolysis elicited by glutamate was significantly increased in the slices prepared from ischaemic rats 24 h after reperfusion, the accumulation of inositol phosphates (InsPs) and inositol 1,4,5-trisphosphate (InsP3) was 614±74% ( n = 8) and 182±11% ( n = 9) of the basal level respectively. This potentiation was also observed 21 days after ischaemia. Hyper-responsiveness to glutamate was also accompanied by an increase in AIF4-stimulated formation of [3H]inositol phosphates. In addition, global ischaemia did not change either high-affinity [3H]glutamate binding in hippocampal membranes or the stimulation of PPI hydrolysis by carbachol or noradrenaline in hippocampal slices. The present results suggest that the increased responsiveness to glutamate is the result, at least in part, of functional changes at the G-protein level, and may contribute to the pathophysiology of ischaemic brain injury or to the regenerative phenomena that accompany ischaemic damage.  相似文献   
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This study sought to pharmacologically characterize bradykinin receptors on SV40-immortalized human trabecular meshwork (HTM3) cells. Phosphoinositide (PI) turnover studies were conducted using [3H]myo-inositol-labeled HTM3 cells and anion exchange chromatography to quantify [3H]inositol phosphates generated in response to bradykinin (BK) and various BK analogs. The blockade of these responses was studied using two potent and receptor-subtype selective antagonists. BK and T-kinin (Ile-Ser-BK; TK) induced a 4.2–4.4 fold stimulation of PI turnover above base levels at 1–10 μM. Several other peptides unrelated to BK, including angiotensin II, endothelin, cholecystokinin, bombesin and peptide YY tested at 1–10 μMwere essentially inactive. The molar potencies (EC50) of BK, TK and close analogs were: BK=4.5±0.5 nM(n=6), Lys-BK=6.5±0.7 nM(n=3), TK=38.8±6.6 nM(n=8), Met-Lys-BK=41.5±13.4 nM(n=4), Des-Arg9-BK=2093±626 nM(n=4). All the latter BK-related peptides>were full agonists. The actions of BK and TK were potently and competitively antagonized by Hoe-140 (molar potency=0.6–1 nM;pA2n=8.97–9.21,n=3–4) and byD-Arg0[Hyp3,-Thi5,8,-DPhe7]-BK (molar potency=251 nM;-log potency, pKb=6.6), two selective B2-type BK antagonists. In conclusion, rank order of potency of BK agonists and the blockade of BK- and TK-induced PI turnover by the selective antagonists are consistent with the classification of the BK receptors on HTM3 cells as the B2-receptor subtype.  相似文献   
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