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81.
细菌对MLS类和糖肽类抗生素产生耐药性的作用机制   总被引:3,自引:0,他引:3  
MLS类和糖肽类抗生素在人类与细菌感染性疾病的对抗中发挥着重要作用.与其他抗生素一样,随着这些抗生素的临床使用,细菌耐药性的出现和不断发展给人们带来新的挑战.本综述对这两类抗生素的细菌耐药性产生机制进行了剖析,并就已开发的若干个新型MLS类和糖肽类抗生素作了介绍.  相似文献   
82.
民俗是社会文化的重要构成,各种文化基因,无时无处不存在它折射出的影印。在民俗活动中,预防疾病、阻断疾病发展、保障机体健康等内容,表现非常充分。  相似文献   
83.
 目的 探讨COX-2基因与基质金属蛋白酶在星形细胞瘤中的表达及二者相关性。方法 用原位杂交的方法检测星形细胞瘤组织中COX-2 mRNA的表达;用Ultrasensitive S-P法(链霉素抗生物素蛋白-过氧化物免疫组化染色)检测同等标本中基质金属蛋白酶-2和基质金属蛋白酶-9蛋白的表达;并将COX-2 mRNA与基质金属蛋白酶的表达作相关性分析。结果 COX-2 mRNA及MMP2、MMP9在星形细胞瘤中高度表达,表达阳性率分别为62.69%、56.70%和58.20%;COX-2 mRNA与MMP2和MMP9均有正相线性关系,Pearson积距相关系数分别为0.260、0.347,P<0.05。结论 COX-2基因和基质金属蛋白酶在星形细胞瘤组织中的表达密切相关,说明它在星形细胞瘤向周围组织侵袭中起重要作用。  相似文献   
84.
AIM: To observe the effects of three cytokines on the apoptosis of Tf-1 cells induced by y irradiation and investigate the relationship between apoptosis and caspase-3 activity. METHODS: Different cytokines GM-CSF, IL-3 and GM-CS/IL-3 fusion protein were added into the irradiated Tf-1 cells. MTT assay, morphology, flow cytometry, and DNA fragmentation assay were used to observe the effects of cytokines on apoptosis. The caspase-3 activity was determined with a fluorocytometer. RESULTS: Irradiated Tf-1 cells showed typical morphological characteristic of apoptosis demonstrated by transmission electron microscopy and were accumulated in G0/G1 phase. In the groups treated with growth factors after irradiation, three cytokines significantly increased the viability rate, distinctly decreased the apoptosis rate and the proportion of DNA fragmentation. When Tf-1 cells were irradiated by y  相似文献   
85.
ObjectiveTo describe an arthroscopic technique for giant meniscal cyst excision with preservation of the functional meniscus, report the short‐ and medium‐term outcomes, and assess magnetic resonance imaging (MRI) for follow‐up imaging evaluations.MethodsA total of 54 consecutive patients with symptomatic meniscal cysts were admitted to the Second Xiangya Hospital of Central South University between 2014 and 2019. Nine patients with giant meniscus cysts (six females and three males) were included in this study. The age range of the patients was 6–34 years. All patients underwent a complete physical examination, X‐ray, Doppler ultrasound, and MRI of the knee preoperatively. After an arthroscopic diagnosis of a meniscal rupture with a giant meniscal cyst, partial meniscectomy, ablation of the cyst, and suturing of the retainable meniscus were performed. Lysholm and International Knee Documentation Committee (IKDC) scores were used preoperatively and at the most recent follow‐up. Clinical outcomes were classified into four categories: excellent, good, fair, and poor. During the last visit, all patients underwent MRI to assess the recurrence of the cyst and meniscal suture healing.ResultsPreoperative MRI and arthroscopic examination revealed giant meniscal cysts combined with meniscal tears and congenital discoid meniscus, and all giant meniscal cysts occurred in the lateral meniscus. The main types of meniscal tears were horizontal and complex tears. The cysts were unicystic in one case and multicystic in eight cases. The mean size of the cysts on the MRI was 5.86 cm × 2.24 cm × 2.48 cm. The mean follow‐up periods were 37.5 (19–60) months. Clinical outcomes were excellent in six patients and good in three patients. The postoperative scores were significantly improved compared to the preoperative scores (Lysholm: 90.78 ± 4.60 vs. 54.56 ± 7.25; IKDC: 96.2 ± 3.46 vs. 61.69 ± 3.36; p <0.01). No recurrence of the cyst was indicated on the MRI, and there was good healing of the torn meniscus.ConclusionsArthroscopic cystectomy combined with the meniscus suture technique was effective to eradicate residual cyst cavities, and traffic orifices be highly recommended.  相似文献   
86.
Hydration of fat-free mass (FFM), defined as the ratio of total body water (TBW) to FFM (TBW/FFM), is stable at 0.739 in adult mammals. However, an increase in the TBW/FFM ratio is common in hemodialysis (HD) patients. This study aimed to evaluate the determinants of TBW/FFM and investigate its predictive value for the prognosis of all-cause mortality in HD patients.We enrolled patients undergoing maintenance HD between July 2020 and May 2021. All patients were prospectively followed until death, HD dropout, or until the end of the study (November 1, 2021). A forward stepwise multivariable linear regression analyses was performed to test the independent relationship between TBW/FMM and other clinical variables. Receiver operating characteristic (ROC) analysis was used to discriminate the TBW/FFM with respect to 180-day mortality.Of the 106 patients, 42 had elevated TBW/FFM levels. Multiple linear regression analysis revealed that the TBW/FFM ratio was significantly associated with extracellular water (ECW)/TBW (standardized regression coefficient [β = 1.131, P < .001], phase angle (PhA) [β = 0.453, P < .001], and sex (β = 0.440, P < .001). We calculated the ROC curve (AUC) of TBW/FFM, ECW, ECW/TBW, and intracellular water (ICW) to compare the discriminatory capacities of these parameters in predicting 180-day mortality. The AUC for TBW/FFM (AUC = 0.849; 95% CI, 0.745–0.953) exhibited better discriminatory potential than ECW (AUC = 0.562; 0.410–0.714), although it had a similar predictive potential as the ECW/TBW ratio (AUC = 0.831; 0.731–0.932). High TBW/FFM can be used as a valuable prognostic index for predicting all-cause mortality in patients on HD.  相似文献   
87.
88.
目的:探讨改良口外须颅颌固定治疗上颌骨骨折的临床效果。方法:对35例上颌骨Le FortⅡ、Ⅲ型骨折患者,先行闭合复位,恢复受伤前的咬合关系,再行改良口外须颅颌固定牵引3~4周。结果:35例Le FortⅡ、Ⅲ型骨折患者总有效率达94.2%。结论:改良口外须颅颌固定牵引治疗上颌骨骨折是一种简单易行、可靠的方法。  相似文献   
89.
1病例资料【例1】女,19岁,未婚,有性生活史。主因停经2个月,在外院查HCG( ),自购米非司酮口服行药物流产,服药物后胚胎排除情况不详,于服药第10天突然出现阴道大出血急诊入院。查体:体温37℃,脉搏74/m in,呼吸20/m in,血压100/60 mmHg。心肺腹未见异常,阴道已婚型,畅通,有鲜血流出,子宫体前位,40天孕大小,软,无压痛,活动可,双侧附件(-)。考虑为药物流产不全,即在常规消毒下行清宫术,上好窥阴器后,发现阴道左侧壁有2个紫蓝色结节,直径0·5 cm和1·2 cm大小,其中1个已破溃大量出血,立即缝扎止血后,查血HCG 23 000 U/m l,考虑绒毛膜癌。用…  相似文献   
90.
BackgroundThere is increasing attention on the association of socioeconomic status and individual behaviors (SES/IB) with mental health. However, the impacts of SES/IB on mental disorders are still unclear. To provide evidence for establishing feasible strategies on disease screening and prevention, we implemented Mendelian randomization (MR) design to appraise causality between SES/IB and mental disorders.MethodsWe conducted a two-sample MR study to assess the causal effects of SES and IB (dietary habits, habitual physical activity, smoking behaviors, drinking behaviors, sleeping behaviors, leisure sedentary behaviors, risky behaviors, and reproductive behaviors) on three mental disorders, including bipolar disorder, major depressive disorder and schizophrenia. A series of filtering steps were taken to select eligible genetic instruments robustly associated with each of the traits. Inverse variance weighted was used for primary analysis, with alternative MR methods including MR-Egger, weighted median, and weighted mode estimate. Complementary methods were further used to detect pleiotropic bias.ResultsAfter Bonferroni correction and rigorous quality control, we identified that SES (educational attainment), smoking behaviors (smoking initiation, number of cigarettes per day), risky behaviors (adventurousness, number of sexual partners, automobile speeding propensity) and reproductive behavior (age at first birth) were causally associated with at least one of the mental disorders.ConclusionsMR study provides robust evidence that SES/IB play broad impacts on mental disorders.  相似文献   
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