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81.
Neurology. 2002;58(9 suppl 6):S3-S9.
That migraine is significantly underdiagnosed in the United States and other countries is well established. New data from a follow-up survey to the American Migraine Study II reveal that the presence of concomitant headache types and co-morbid conditions significantly affects the ability to detect and diagnose migraine. This article describes these data and explores the contribution of concomitant headache types and co-morbidities to the problem of underdiagnosis of migraine. Migraine continues to be underdiagnosed because of failure to recognize it (missed diagnosis) and because of misdiagnosis of migraine as another headache type. First, a diagnosis of migraine may be missed in the presence of other headache types that occur proportionally more frequently than migraine and thereby overshadow migraine. Second, migraine may be misdiagnosed when health-care providers inappropriately interpret specific symptoms and co-morbid conditions as indicators of the presence of a non-migraine headache type such as sinus or tension. By becoming aware of these diagnostic pitfalls and being more judicious and deliberate in diagnosing migraine and other headache types, health-care providers can improve the diagnosis of migraine and patients to receive appropriate therapy.
Comment: The diagnosis of migraine is less likely to be made if the patient has several types of headache presentations over time. Thus, a patient with the full spectrum of migraine, from episodic tension-type through migrainous (probable migraine) headache and on to migraine per se is far less likely to receive a diagnosis of migraine than a patient who experiences attacks of "pure" migraine. SJT  相似文献   
82.
目的:胰岛干细胞移植是治疗糖尿病的一条新途径,可避免胰腺供体匮乏及长期使用免疫抑制剂的问题。本文对有关胰岛干细胞的来源、诱导分化及其分子标记物等研究进展做一综述。资料来源:应用计算机检索PUBMED 1997-06/2006-06期间的相关文章,检索词为“pancreatic,stem cell,differentiate,marker”,并限定文章语言种类为English。同时计算机检索万方数据库1997-06/2006-06期间的相关文章,检索词为"胰岛干细胞,诱导分化,分子标记物",并限定文章语言种类为中文。资料选择:对资料进行初审,并查看每篇文献后的引文。纳入标准:文章所述内容应与胰岛干细胞的来源、诱导分化及其分子标记物研究相关。排除标准:重复研究或Meta分析类文章。资料提炼:共收集到82篇相关文献,31篇文献符合纳入标准,排除的51篇文献为内容陈旧或重复。符合纳入标准的31篇文献中,6篇涉及主要概念,15篇涉及胰岛素分泌细胞的来源及其诱导分化,9篇涉及胰岛干细胞的分子标志,2篇涉及目前存在的问题。资料综合:干细胞是具有自我更新能力的多潜能细胞,分为胚胎干细胞和成体干细胞两大类。胰腺干细胞属于成体干细胞,能在体内分化成导管细胞、胰岛素分泌细胞、外分泌腺胞等特定胰腺组织细胞型,并具有无限分裂和永久自我更新能力。胰岛干细胞的来源、诱导分化及其分子标记物等研究对糖尿病治疗有非常重要的意义。近年研究表明:胰岛素分泌细胞主要来源于胚胎干细胞和成体干细胞,如胰腺导管上皮细胞、巢蛋白阳性胰岛前体细胞、骨髓间充质干细胞、肝脏干细胞等的诱导分化,也可利用基因工程获得。胰岛干细胞的分子标志对基础和临床研究均有重要意义,目前所使用的主要分子标志主要有PDX-1、巢蛋白、角蛋白19、角蛋白20、神经原素3、9.5蛋白基因产物等,可用于胰岛干细胞鉴定、分离及纯化。结论:胰岛细胞及干细胞移植的研究发展迅速,胰岛干细胞的来源及鉴定取得了突破性进展,但还有很多问题急需解决。随着干细胞研究的深入发展和技术的不断完善,必将能够在体外培育出数量充足的胰岛细胞供移植之用。  相似文献   
83.
目的:观察强化糖尿病教育对老年2型糖尿病患者血糖控制的影响,并对教育的方法模式及患者的顺应性作出评价。方法:①随机选取老年2型糖尿病患者156例,均为2004-03/07青岛大学医学院附属医院门诊就诊患者,年龄(64.7±6.6)岁,病程(10.54±7.06)年。②入选患者在原有糖尿病治疗方案的基础上进行强化糖尿病教育:入选后半年之内每月进行一次糖尿病教育,半年后每3个月一次教育,教育以糖尿病有关知识专题集体讲座为主,辅以答疑。专人负责电话通知患者教育讲座的具体的时间、地点和内容。每次讲座时监测空腹血糖、餐后2h血糖,入选时、教育后第6,12个月测定糖化血红蛋白;同时记录患者接受教育频率,计算依从率。③采用随机区组设计的方差分析(广义线性模型)分析数据完整的患者的空腹血糖、餐后2h血糖及糖化血红蛋白随时间变化情况(入选时、第6,12个月时)。结果:①依从率:入选时156例,第2次教育时为125例,依从率74.8%,随着时间的延长,接受强化教育的患者逐渐减少,至第6个月时依从率28.1%,至1年时仅有33例接受教育,依从率为21.2%。②完成全程教育的33例患者的资料:教育第6,12个月时的空腹血糖、餐后2h血糖较入选时下降[空腹血糖:(7.9±2.1),(7.8±1.4),(9.7±2.1)mmol/L,F=31.05,P<0.01;餐后2h血糖:(12.0±4.0),(12.2±3.3),(17.8±3.8)mmol/L,F=56.61,P<0.01];糖化血红蛋白在教育第6,12个月也较入选时下降,但无统计学意义[(7.0±1.1)%,(6.9±1.1)%,(7.6±1.7)%,F=2.97,P=0.06]。结论:强化糖尿病教育可使老年2型糖尿病患者血糖有效持续稳定地控制,但患者接受强化教育的依从性差。  相似文献   
84.
The transfusion of blood may suppress the immune responses of patients with renal transplants and with malignant disorders. To study the in vitro suppressive effects of banked blood, 4 units of blood were stored in CPDA-1 and ADSOL at 4 degrees C for 14 days. Lymphocytes and plasma or ADSOL supernatants were harvested on Days 0, 4, 7, 10, and 14. Subpopulations of lymphocytes were enumerated by flow cytometry. Recalcified and heat-treated plasma and supernatants from the units of blood were added to mixed lymphocyte cultures (MLC) composed of cells from normal individuals. No significant changes were noted in the proportions of T or B cells from blood stored under these conditions. A 60 +/− 3 percent inhibition in the proliferative response was observed when plasma from CPDA-1 units was added to MLCs (p less than 0.02). Supernatants from ADSOL units demonstrated a 29 +/− 4 percent inhibition (p less than 0.10) of the proliferative response, and this inhibition of response was observed on all 14 days of the study. When appropriate concentrations of dextrose or adenine were added to other MLCs, adenine (at the concentration found in ADSOL) caused a significant inhibition of the proliferative response. This inhibition was not, however, as marked as that observed with recalcified, heat- treated plasma from CPDA-1 units. We conclude that adenine plus some additional factor(s) found in the liquid portion of stored blood inhibits the proliferative response of normal lymphocytes. It is possible that these factors contribute to the immune suppression observed in vivo in some patients who receive blood transfusions.  相似文献   
85.

Background and Purpose

To evaluate the ability of cannabidiolic acid (CBDA) to reduce nausea and vomiting and enhance 5-HT1A receptor activation in animal models.

Experimental Approach

We investigated the effect of CBDA on (i) lithium chloride (LiCl)-induced conditioned gaping to a flavour (nausea-induced behaviour) or a context (model of anticipatory nausea) in rats; (ii) saccharin palatability in rats; (iii) motion-, LiCl- or cisplatin-induced vomiting in house musk shrews (Suncus murinus); and (iv) rat brainstem 5-HT1A receptor activation by 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) and mouse whole brain CB1 receptor activation by CP55940, using [35S]GTPγS-binding assays.

Key Results

In shrews, CBDA (0.1 and/or 0.5 mg·kg−1 i.p.) reduced toxin- and motion-induced vomiting, and increased the onset latency of the first motion-induced emetic episode. In rats, CBDA (0.01 and 0.1 mg·kg−1 i.p.) suppressed LiCl- and context-induced conditioned gaping, effects that were blocked by the 5-HT1A receptor antagonist, WAY100635 (0.1 mg·kg−1 i.p.), and, at 0.01 mg·kg−1 i.p., enhanced saccharin palatability. CBDA-induced suppression of LiCl-induced conditioned gaping was unaffected by the CB1 receptor antagonist, SR141716A (1 mg·kg−1 i.p.). In vitro, CBDA (0.1–100 nM) increased the Emax of 8-OH-DPAT.

Conclusions and Implications

Compared with cannabidiol, CBDA displays significantly greater potency at inhibiting vomiting in shrews and nausea in rats, and at enhancing 5-HT1A receptor activation, an action that accounts for its ability to attenuate conditioned gaping in rats. Consequently, CBDA shows promise as a treatment for nausea and vomiting, including anticipatory nausea for which no specific therapy is currently available.  相似文献   
86.
The development of red cell (RBC) alloantibodies in infants less than 4 months of age is believed to be rare. Though there are no well-documented published accounts, the formation of alloanti-E in a multiply transfused 11-week-old infant is reported here. The infant, blood group B, D +, developed necrotizing enterocolitis and renal failure requiring 31 transfusions of washed and unwashed RBCs (group B and group O), as well as fresh-frozen plasma and platelets. Six weeks after the first blood transfusion, alloanti-E was detected. The anti-E weakly agglutinated R2R2 screening RBCs at 37 degrees C and sensitized these RBCs to react with anti-IgG. The infant's RBCs were typed as E-. Passive transfer of alloanti-E was ruled out by the negative antibody screening tests of each donor unit and the absence of any RBC alloantibodies in the mother's serum. Stored samples of the infant's sera were tested, and anti-E was shown to be present approximately 11 days after exposure to a known E+ RBC unit. The appearance of alloanti-E in this time frame is consistent with a secondary immune response. Primary immunization most likely took place in the first 4 weeks of transfusion therapy.  相似文献   
87.
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90.
The double-fissure sign: a motion artifact on thin-section CT scans   总被引:1,自引:0,他引:1  
Mayo  JR; Muller  NL; Henkelman  RM 《Radiology》1987,165(2):580-581
A motion artifact has been observed that may affect the number of fine interstitial lines seen at thin-section (1.5-mm-collimation) computed tomography (CT) for the evaluation of interstitial lung disease. In 14 of 42 patients, one or both major fissures appeared as two parallel lines rather than as a single line. This was more common in the left lung base. Using a phantom, the authors were able to reproduce the phenomenon by simulating cardiac motion. Therefore, this motion may lead to an artifactual increase in the number of interstitial lines.  相似文献   
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