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排序方式: 共有510条查询结果,搜索用时 15 毫秒
1.
目的 对北京市朝阳区某学校一起耐药肺结核疫情进行分析,为今后耐药结核病疫情的处置提供参考。方法 对病例进行流行病学调查,对病例密切接触者采用PPD试验、X线胸片和CT相结合的方式筛查。结果 2018年10月—2019年6月,该校共发生36例肺结核病例,发病率为4.5%。其中5例耐多药,3例耐利福平。36例病例分布在四个班,15a班27例、15b班4例、15c班2例、17d班3例。各班发病率分别为56.3%、8.3%、5.7%、7.1%,差异有统计学意义(P<0.01)。8例耐药病例中6例为15a班学生,占耐药病例总数的75.0%。经CT筛查68名密切接触者中确诊23例肺结核患者,检出率33.8%。结论 该起学校聚集性疫情为全国首起耐药肺结核聚集性疫情,首发病例未及时就医,传染源隐匿存在时间长,是导致该起疫情发生的主要原因。疫情处置中开展密切接触者筛查对于及时发现新病例非常重要。  相似文献   
2.
牛强卫 《中国骨伤》2007,20(4):276-276
手指屈肌腱腱鞘炎,又称扳机指或弹响指,是手指腱鞘因机械性摩擦而引起的慢性无菌性炎症改变。腱鞘增厚致使腱鞘狭窄,肌腱与腱鞘之间亦可发生粘连,肌腱发生变性、变形,致手指活动受限[1]。本病可发生于不同年龄,对患者日常生活及工作影响较大。我院从2004年以来采用闭合松解术治疗手指屈指肌腱腱鞘炎32例,效果满意,报告如下。1临床资料本组32例,男10例,女22例;年龄23~68岁,平均45岁。发生于拇指25例,食指2例,中指4例,无名指1例;病程3~24个月。主要症状体征:早期手指屈伸时疼痛,严重时不能自主屈伸,有交锁现象,被动屈伸时有摩擦感伴有弹响及疼…  相似文献   
3.
The purpose of the present study was to determine the reliability of several selected signs of trauma from occlusion and their relations with severity of periodontitis. 32 moderate to advanced chronic periodontitis patients participated in the study. All teeth present were evaluated for various abnormal occlusal contacts, signs of trauma from occlusion, and the severity of periodontitis. Standardized periapical radiographs were also taken for each tooth. The results demonstrated that: (1) no significant difference occurred in probing pocket depth (PD), clinical attachment loss (AL), or percentage of alveolar bone height (BH) between teeth with and without various abnormal occlusal contacts, i.e., premature contacts in centric relation occlusion, non-working contacts in lateral excursions, premature contacts of anterior teeth or posterior protrusive tooth contacts; (2) teeth with either significant mobility, functional mobility, or radiographically widened periodontal ligament space (PDLS) had deeper PD, more AL and lower BH than teeth without these signs, while teeth with pronounced wear or radiographically thickened lamina dura had less AL than teeth without these findings; (3) 2 combined indices, i.e., the trauma from occlusion index (TOI) and the adaptability index (AI), were proposed for the identification of occlusal trauma and the response of periodontium to excessive biting forces in heavy function, respectively; TOI-positive teeth exhibit deeper PD, more AL and less osseous support than TOI-negative teeth; however, AI-positive teeth had less AL and more osseous support than AI-negative teeth; (4) with identical attachment level, TOI-positive teeth had less osseous support than TOI-negative teeth while the magnitude of difference became greater with an increase of attachment loss.  相似文献   
4.
闭合复位经皮螺钉内固定治疗跖跗关节损伤   总被引:9,自引:0,他引:9  
目的探讨应用闭合复位经皮螺钉内固定治疗跖跗关节损伤的临床疗效。方法自2003年1月~2005年6月应用闭合复位经皮螺钉内固定治疗跖跗关节损伤26例。按照Myerson分类:中间柱损伤13例,内侧、中间柱合并损伤7例,内侧、中间、外侧柱三柱损伤6例。结果本组切口均一期愈合,平均手术时间为40min(30~70min),切口长度平均为5mm;所有患者获平均11.4个月(6~17个月)随访,根据美国足踝骨科协会(AOFAS)评分平均为87分,患者术后平均5.3个月(3~11个月)恢复正常生活。结论闭合复位经皮螺钉内固定手术创伤小,软组织并发症低,能有效治疗跖跗关节复合体损伤;中间柱复位并沿Lisfranc韧带方向插入螺钉内固定是重建跖跗关节复合体稳定性的关键。  相似文献   
5.
The effect of externally applied mechanical stress was investigated by thin section electron microscopy of the microvessels in the unaffected palmar fascia in the carpal tunnel syndrome and in patients with Dupuytren's contracture before and after application of a continuous elongation device. In the unaffected palmar fascia the microfilaments of the endothelial cells were connected to a few adherens junctions and focal contacts; stress fibres were absent. In the cord of Dupuytren's disease the microfilaments were increased in quantity. The length ratios of the connections with the lateral and basal cell membrane were significantly higher than in the control group and increased to an even greater extent in the continuously extended fascia. Stress fibres appeared in the endothelial cells of postcapillary venules in the nonextended cord and in the endothelium of both arterioles and venules after extension elongation. The numerous intermediate filaments and the rare microtubules remained unchanged in the endothelial cells of all palmar fasciae analysed. In the endothelial cells of the microvessels the mechanical stress applied from outside mainly affected the contractile component of the cytoskeleton.  相似文献   
6.
目的:探讨双关节骨外固定器治疗桡骨远端复杂性骨折的效果。方法:对16例老年人桡骨远端复杂性骨折采用手法闭合复位、双关节骨外固定器固定进行治疗。结果:随访8~38个月,骨折均获得良好的复位与固定,疗效较满意。结论:手法复位,双关节外固定器治疗桡骨远端复杂性骨折,可有效矫正畸形,重建桡腕关节的稳定,是一种微创、安全、疗效确切的治疗方法。  相似文献   
7.
以医疗典型纠纷案例为例,通过厘清相关法律对患者知情同意权行使及代为行使的相关规定,探讨知情同意权代为行使行为的界定。启示如下:知情同意权代为行使应设前置条件进行限制和约束;代为行使主体包括近亲属或关系人、委托代理人;患者本人意见具有首要优先性,委托代理人意见应优先于近亲属意见。  相似文献   
8.
SETTING:Rural Eastern Cape, South Africa.OBJECTIVE:To identify steps in the TB preventive care cascade from routinely collected data among TB patients at a district hospital prior to the implementation of a novel TB program.DESIGN:This was a retrospective study. We adapted the TB prevention cascade to measure indicators routinely collected at district hospitals for TB using a cascade framework to evaluate outcomes in the cohort of close contacts.RESULTS:A total of 1,722 charts of TB patients were reviewed. The majority of patients (87%) were newly diagnosed with no previous episodes of TB. A total of 1,548 (90%) patients identified at least one close contact. A total of 7,548 contacts were identified with a median of 4.9 (range 1–16) contacts per patient. Among all contacts identified, 2,913 (39%) were screened for TB. Only 15 (0.5%) started TB preventive therapy and 122 (4.4%) started TB treatment. Nearly 25% of all medical history and clinical information was left unanswered among the 1,722 TB charts reviewed.CONCLUSION:Few close contacts were screened or started on TB preventive therapy in this cohort. Primary care providers for TB care in district health facilities should be informed of best practices for screening and treating TB infection and disease.  相似文献   
9.
目的 分析西安市新型冠状病毒肺炎(COVID-19)无症状感染者的特征,为更好地防控疫情提供参考依据。方法 收集疫情应急处置期间无症状感染者的现场流行病学调查资料,采用描述性流行病学方法进行分析。结果 截至2020年5月10日,西安市共报告无症状感染者25例(男12例,女13例),中位年龄46.0(18.5,65.0)岁,占全市17.24%(25/145)。其中15例(60.00%)为确诊病例密切接触者,8例(32.00%)有湖北旅居史,2例(8.00%)为无症状感染者的密切接触者;23例(92.00%)经聚集性疫情传染源溯源和确诊病例/无症状感染者密切接触者排查发现,1例(4.00%)为协查外市确诊病例密切接触者发现,1例(4.00%)为筛查高危地区来陕人群发现。25例无症状感染者末次暴露到首次核酸检测阳性中位时间为17.0 d,集中医学观察开始至首次核酸检测阳性中位时间为8.0 d,首次核酸检测阳性至转阴出院中位时间为14.0 d。CT显示78.57%(11/14)无症状感染者肺部存在不同程度的小结节影、斑片状影、磨玻璃样影和边界欠清晰状况。结论 无症状感染者主要经聚集性疫情调查和确诊病例/无症状感染者密切接触者排查发现。及时全面排查密切接触者并对其进行集中医学观察,能减少其可能造成的疫情持续传播。肺部影像学特征性改变可作为早期排查的重要参考。  相似文献   
10.
The mechanism by which nerve - muscle contacts are reduced during postnatal development of the rat soleus muscle was investigated using electrophysiological methods. Between days 7 and 9 after birth, soleus muscle fibres lose 0.19–0.24 terminals per muscle fibre within 24 h. A much more rapid loss of contacts is seen when muscles are exposed in vitro to acetylcholine (10−3 g/ml). In this case 0.67–0.87 terminals per muscle fibre lose contact within 2 h. The loss of neuromuscular contacts induced by acetylcholine can be reduced by preincubating the muscles in solutions containing acetoxymethyl ester of 1,2-bis(2-amino-phenoxylethane-N,N1;N1-tetraacetic acid (BAPTA-AM), a Ca2+ chelating agent that enters cells and reduces the Ca2+ transients inside the cell. Treatment of muscles with nifedipine, which blocks dihydropyridine-sensitive (L-type) Ca2+ channels, also reduced the acetylcholinesterase-induced loss of neuromuscular contacts. The results indicate that transient increases in Ca2+ inside nerve terminals contribute to loss of neuromuscular contacts, and that these increases occur by Ca2+ entry through L-type channels.  相似文献   
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