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831.
目的:SLC18A2基因的P387L突变在中国汉族散发性帕金森病人群的关联研究。方法:在931例汉族人群 中(包括455例散发性帕金森病患者和476例正常对照者)应用飞行时间质谱分析(matrix-assisted laser desorption/ionization- time-of-fl ight mass spectrometry,MALDI-TOF MS)技术测定P387L基因型,并应用Sanger测序的方法对结果进一步验证。 同时采用病例-对照研究,探索该突变与散发性帕金森病的关联。结果:在本组931个研究个体中均未发现该突变位 点。结论:该突变位点在中国汉族人群中很罕见,可能并非中国汉族散发性帕金森病人群的致病突变位点,该突变 位点与帕金森病之间的关联尚需扩大样本及在其他种族人群中进行验证。  相似文献   
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干燥综合征(SS)是一种慢性自身免疫性疾病,常侵犯泪腺、唾液腺等外分泌腺,同时还会造成肺、肾、消化和神经系统损害甚至累及全身器官。其病因复杂,发病机制目前尚未完全阐明。本病临床治疗为对症治疗,常用药物为免疫抑制剂,糖皮质激素等。白芍总苷辅助治疗本病可改善患者的外分泌腺功能,具有较好的临床疗效和安全性。本文从白芍总苷治疗SS的相关机制进行综述,以期为相关实验研究及临床提供更多的理论依据。  相似文献   
835.
A new dual-screen, dual-emulsion-film combination that allows a decrease in radiation dose of approximately 66% was compared with a widely used single-screen, single-emulsion-film system in contact and magnification mammography. Clustered microcalcifications randomly superimposed on a breast phantom were detected, and the location and number of individual calcifications were determined by four observers. The detectability of calcifications, determined with a receiver operating characteristic (ROC) analysis area, was 0.92 for magnification and 0.82 for contact mammography with the single-emulsion-film system, compared with 0.84 and 0.72, respectively, with the dual-emulsion-film system. More clusters were correctly located and more individual calcifications were counted with magnification than with contact mammography. The dual-emulsion-film system with the magnification technique performs as well as the single-emulsion-film system with the contact technique, while retaining a decrease in required dose of approximately 40%.  相似文献   
836.
Psychiatric disorders in pregnancy   总被引:1,自引:0,他引:1  
This review, although not exhaustive, provides information on the potential impact of psychiatric illness on obstetric outcome. There is clear evidence that psychiatric illness poses a risk to pregnancy outcome. There productive safety data on many of the available treatments fail to demonstrate a clear risk from treatment. The medications with clear teratogenic, neonatal, and developmental risks are, not surprisingly, those used to treat some of the most severe and debilitating psychiatric illnesses. Even the amount of information available is inadequate without some straightforward clinical guidelines. A model of risk for illness and treatments of illnesses during pregnancy developed by the authors' group reminds clinicians that nonexposure does not exist. Rather, the decision is which type of exposure is in the best interest of the patient and family-exposure to illness or exposure to treatment. Regardless of the choice, clinicians are encouraged to think in terms of reducing the total number of exposures; that is, if choosing to treat, patients should be kept well by adjusting and monitoring medications-partial treatment simply provides exposure to illness and treatment. Guidelines to accomplish the goal of minimizing exposures include: 1. Treating women of reproductive capacity from the first visit as if they are pregnant: choosing treatments with reproductive safety information (eg, new and improved = no data) and providing supplemental folic acid for all women (800 microg), with higher doses for those treated with anticonvulsants (3 to 4 mg).2. For women who conceive while taking a medication, and if it was efficacious for them, then the majority of decisions for medication selection should be considered already made for pregnancy and lactation (eg, do not switch medications once pregnant or for breastfeeding, as that simply exposes the baby to a second medication and the data previously discussed do not apply). 3. Because the serum concentration of most medications decreases during pregnancy, establishing criteria a priori for increasing the maternal daily dose; as a general rule, sleep patterns are good markers of psychiatric illnesses. 4. Always preferring monotherapy to two medications. 5. Obtaining up-to-date information at www.emorywomensprogram.org (a website with links to many support groups, reproductive safety registries) or other women's health websites. These basic guidelines can help decrease the number of exposures and aid in conducting clinical care with at least some reproductive safety data.  相似文献   
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839.

Objective

To screen the chitosan producing ability of endolichenic fungi and its antibacterial activity.

Methods

Lichen collected from mangroves was screened for endophytes and the chitosan producing ability of endolichenic fungi by submerged fermentation was also determined. Antibacterial activity was carried out against different pathogens.

Results

Totally 4 different groups of fungi were isolated from the lichen Roccella montagnei. Among the four genera, Aspergillus niger (A. niger) is potential to produce chitosan (1.3 g/L) on the twelfth day of incubation. Glucose plays an important role in the productivity of chitosan and the yield was maximum at 10% (1.93 g/L). Antibacterial activity revealed that Vibrio cholerae was sensitive to chitosan followed by Escherichia coli.

Conclusions

In conclusion, our findings suggest that A. niger is a potential candidate to produce more chitosan than the other strains and glucose plays an important role in the production of chitosan which proves to have a good antibacterial activity.  相似文献   
840.
Herrmann SD, Snook EM, Kang M, Scott CB, Mack MG, Dompier TP, Ragan BG. Development and validation of a Movement and Activity in Physical Space score as a functional outcome measure.

Objective

To develop and validate a functional measure, the Movement and Activity in Physical Space (MAPS) score, that encompasses both physical activity and environmental interaction.

Design

Observational matched-pair cohort with 2-month follow-up.

Setting

General community under free-living conditions.

Participants

Adult participants (N=18; n=9 postsurgical, n=9 matched control; mean age ± SD, 28.9±12.0y) were monitored by an accelerometer and global positioning system receiver for 3 days within 1 week (4.1±2.8d) after knee surgery (T=0) and 2 months later (T+2). The healthy controls were matched for age, sex, smoking, perceived physical activity level, and occupation of a postsurgical participant. Correlation, t test (with Bonferroni adjustment: α=.05/2), analysis of variance, and intraclass correlation coefficient were used to establish validity and reliability evidence.

Interventions

Not applicable.

Main Outcome Measure

MAPS scores.

Results

MAPS scores were moderately correlated with the Knee Injury and Osteoarthritis Outcome Score (P<.05). There was a significant group difference at T = 0 for MAPS (t9.9=–3.60; P=.01). Analysis of variance results for the MAPS indicated a time and group interaction (F1,12=4.60, P=.05). Reliability of 3 days of MAPS scores ranged from 0.75 to 0.81 (postsurgical and control), and 2-month test-retest reliability in the control group was 0.94.

Conclusions

The results provide a foundation of convergent and known-group difference validity evidence along with reliability evidence for the use of MAPS as a functional outcome measure.  相似文献   
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