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991.
广西藤茶中黄酮类成份的提取工艺研究   总被引:18,自引:0,他引:18  
目的:提取分离藤(Ampelosis grossdentata)中的双氢杨梅树皮素(dihydromyricetin)和杨梅素(Myricetin)。方法:采用新的水提取和溶剂分离的方法,经化学和光谱鉴定确定结构。结果:提取产物经确证为双氢杨梅树皮素(dihydromyricetin)和杨梅素(Myricetin),平均收率分别为19.6%和0.51%。结论:该提取法经济、简便,易于操作并且提取率  相似文献   
992.

Background and purpose:

Cyclooxygenase inhibitors function to reduce levels of prostaglandin E2 (PGE2) and are broadly efficacious in models of bladder overactivity. We therefore investigated a regulation of urinary bladder function in conscious rats by modulation of the EP3 receptor for PGE2.

Experimental approach:

The activity of the EP3 receptor agonist GR63799X, and EP3 receptor antagonists, CM9 and DG041, at recombinant EP3 receptors was evaluated in vitro. In vivo, intraduodenal dosing during conscious, continuous-filling cystometry of spontaneously hypertensive rats was utilized to determine the urodynamic effect of EP3 receptor modulation.

Key results:

GR63799X dose-dependently (0.001–1 mg·kg−1) reduced bladder capacity, as indicated by a reduction in both the micturition interval and volume of urine per void. In contrast, CM9 (10 and 30 mg·kg−1) and DG041 (30 mg·kg−1) enhanced bladder capacity, as indicated by significantly longer micturition intervals and larger void volumes. CM9 and DG041 inhibited the responses to GR63799X supporting the in vivo activity of these pharmacological agents at the EP3 receptor. In addition to its effect on bladder capacity, GR63799X increased endogenous urine production. Intra-arterial infusion of saline mimicked the enhancement of urine flow observed with GR63799X, and the response was inhibited by CM9.

Conclusions and implications:

These data support the EP3 receptor as a modulator of urinary bladder activity in the conscious rat, and in addition, indicate a role for EP3 receptor activity in regulating urine flow.  相似文献   
993.
Abstract:  Musculoskeletal problems have become a significant issue for the profession of dentistry and dental hygiene. This review provides a detailed examination and discussion regarding the prevalence of musculoskeletal disorders (MSD) in dental personnel and possible causative factors. All research studies or literature reviews, which have reported on the prevalence of musculoskeletal symptoms and/or potential risk factors for this problem in dentists, dental hygienists and dental students, were selected for inclusion. Our literature suggests that the prevalence of general musculoskeletal pain ranges between 64% and 93%. The most prevalent regions for pain in dentists have been shown to be the back (36.3–60.1%) and neck (19.8–85%), while the hand and wrist regions were the most prevalent regions for dental hygienists (60–69.5%). Interestingly, we found that studies on MSDs among dental and dental hygiene students are quite limited. Many risk factors have been identified, including static and awkward posture and work practices. Overall, the review suggests that musculoskeletal problems represent a significant burden for the dental profession. More research in the form of larger studies is urgently required, to help more clearly elucidate the development of this important issue for dental hygienists and dental hygiene students.  相似文献   
994.
995.
One of the most common genetic events in acute myeloid leukemia (AML) is the t(8;21) (q22;q22) translocation, which contributes to leukemic transformation. However, different lines of evidence suggest that the AML1-ETO rearrangement is not sufficient to cause the full leukemic phenotype. Secondary genetic alterations such as mutations in receptor tyrosine kinases are thus required to induce overt AML. The incidence of c-KIT mutations in exon 17 was evaluated in 37 Spanish patients with AML1-ETO+ leukemias. c-KIT mutations were present in only two cases (6.6%) and were shown to be associated with an adverse outcome. The frequency of c-KIT mutations described here is much lower than in other reports.  相似文献   
996.

Background  

HIV-infected subjects have high incidence rates of Staphylococcus aureus infections, with both methicillin-susceptible and methicillin-resistant (MRSA) strains. Possible explanations could include the high burden of colonization, the behavioral risk factors, and the frequent exposures to health care facilities of HIV-infected patients. The purpose of the study was to assess the risk factors for clinically- significant methicillin-resistant Staphylococcus aureus (CS-MRSA) infections in HIV-infected patients admitted to Infectious Diseases Units.  相似文献   
997.
The specific aims of this study were to (1) examine the psychometric properties (unidimensionality, differential item functioning, scale coverage) of an item bank of upper-extremity skills for children and adolescents with cerebral palsy (CP); (2) evaluate a simulated computer-adaptive test (CAT) using this item bank; (3) examine the concurrent validity of the CAT with the Pediatric Outcomes Data Collection Instrument (PODCI) upper-extremity core scale; and (4) determine the discriminant validity of the simulated CAT with Manual Ability Classification System (MACS) levels and CP type (i.e. diplegia, hemiplegia, or quadriplegia). Parents ( n =180) of children and adolescents with CP (spastic diplegia 49%, hemiplegia 22%, or quadriplegia 28%) consisting of 102 males and 78 females with a mean age of 10 years 6 months (SD 4y 1mo, range 2–21y), and MACS levels I through V participated in calibration of an item pool and completed the PODCI. Confirmatory factor analyses supported a unidimensional model using 49 of the 53 upper-extremity items. Simulated CATs of 5, 10, and 15 items demonstrated excellent accuracy (intraclass correlation coefficient [ICCs] >0.93) with the full item bank, had high correlations with the PODCI upper-extremity core scale score (ICC 0.79), and discriminated among MACS levels. The simulated CATs demonstrated excellent overall content coverage over a wide age span and severity of upper-extremity involvement. The future development and refinement of CATs for parent report of physical function in children and adolescents with CP is supported by our work.  相似文献   
998.

INTRODUCTION

By December 2008, 90% of referrals requiring hospital admission will need to be seen and treated within the 18-week patient pathway. Previously, patients within our trust with suspected carpal tunnel syndrome had to wait 3 months to see a specialist in clinic and, once assessed, would have to wait up to a further 6 months for an open carpal tunnel decompression under local anaesthetic (OCTD/LA). We set up a one-stop clinic, where patients would have their out-patient consultation and surgery on the same day. We evaluated the clinic in order to assess whether it led to reduced waiting times whilst maintaining good clinical outcome and patient satisfaction.

PATIENTS AND METHODS

Patients were selected on the basis of the standard referral letter alone. Those selected were then assessed by a single surgeon in the clinic. The patients deemed appropriate underwent an OCTD/LA and were discharged the same day. Patients were followed up with a patient satisfaction and Boston questionnaire.

RESULTS

Forty-six patients underwent 63 OCTD/LA, waiting an average of 2.2 months (9 weeks) from referral. There was high patient satisfaction and improvement in symptoms following treatment in the clinic.

CONCLUSIONS

We believe a one-stop carpal tunnel clinic can be an efficient and cost-effective way of treating this common condition.  相似文献   
999.
Wright  DG; Kauffmann  JC; Chusid  MJ;  Herzig; Gallin  JI 《Blood》1975,46(6):901-911
Continuous flow filtration leukopheresis (FL) is a relatively simple, inexpensive, and efficient technique of harvesting blood neutrophils from normal donors for transfusion into neutropenic recipients. There has been concern, however, that neutrophils may be functionally altered druing this leukopheresis procedure. Human neutrophils obtained by various FL techniques were studied for in vitro chemotaxis by a 51Cr-radiolabel method and for in vitro killing and phagocytosis of Staphylococcus aureus. We compared their function with neutrophils obtained by the NCI-IBM cell separator and by dextran sedimentation from whole blood. FL neutrophils eluted from nylon filters after 3-hr collection periods were functionally abnormal by all parameters tested, while neutrophils obtained by cell separator after similar collection times were not significantly different from control cells. However, neutrophils from 3-hr FL collections were found to include both normal and abnormal populations of cells. Loosely adherent cells, eluted after tapping the filters, were functionally normal; more adherent cells, eluted after tapping the filters and representing the bulk of cells collected, were progressively more abnormal the less readily they were eluted. Shortened FL collection times (1-2 hr) were found to decrease the functional defects. Also, administration of dexamethasone to donors prior to filtration leukopheresis diminished the functional defects of FL neutrophils perhaps by altering adherence characteristics of the cells. These studies show that neutrophils obtained by filtration leukopheresis are functionally abnormal in relation to the time and extent of adherence to nylon filters.  相似文献   
1000.
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