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991.

Background

The QUOROM and PRISMA statements were published in 1999 and 2009, respectively, to improve the consistency of reporting systematic reviews (SRs)/meta-analyses (MAs) of clinical trials. However, not all SRs/MAs adhere completely to these important standards. In particular, it is not clear how well SRs/MAs of acupuncture studies adhere to reporting standards and which reporting criteria are generally ignored in these analyses.

Objectives

To evaluate reporting quality in SRs/MAs of acupuncture studies.

Methods

We performed a literature search for studies published prior to 2014 using the following public archives: PubMed, EMBASE, Web of Science, the Cochrane Database of Systematic Reviews (CDSR), the Chinese Biomedical Literature Database (CBM), the Traditional Chinese Medicine (TCM) database, the Chinese Journal Full-text Database (CJFD), the Chinese Scientific Journal Full-text Database (CSJD), and the Wanfang database. Data were extracted into pre-prepared Excel data-extraction forms. Reporting quality was assessed based on the PRISMA checklist (27 items).

Results

Of 476 appropriate SRs/MAs identified in our search, 203, 227, and 46 were published in Chinese journals, international journals, and the Cochrane Database, respectively. In 476 SRs/MAs, only 3 reported the information completely. By contrast, approximately 4.93% (1/203), 8.81% (2/227) and 0.00% (0/46) SRs/Mas reported less than 10 items in Chinese journals, international journals and CDSR, respectively. In general, the least frequently reported items (reported≤50%) in SRs/MAs were “protocol and registration”, “risk of bias across studies”, and “additional analyses” in both methods and results sections.

Conclusions

SRs/MAs of acupuncture studies have not comprehensively reported information recommended in the PRISMA statement. Our study underscores that, in addition to focusing on careful study design and performance, attention should be paid to comprehensive reporting standards in SRs/MAs on acupuncture studies.  相似文献   
992.
Among animals with multiple reproductive episodes, changes in adult condition over time can have profound effects on lifetime reproductive fitness and offspring performance. The changes in condition associated with senescence can be particularly acute for females who support reproductive processes from oogenesis through fertilization. The pomace fly Drosophila melanogaster is a well-established model system for exploring the physiology of reproduction and senescence. In this review, we describe how increasing maternal age in Drosophila affects reproductive fitness and offspring performance as well as the genetic foundation of these effects. Describing the processes underlying female reproductive senescence helps us understand diverse phenomena including population demographics, condition-dependent selection, sexual conflict, and transgenerational effects of maternal condition on offspring fitness. Understanding the genetic basis of reproductive senescence clarifies the nature of life-history trade-offs as well as potential ways to augment and/or limit female fertility in a variety of organisms.  相似文献   
993.
Early brain injury and delayed cerebral vasospasm both contribute to unfavorable outcomes after subarachnoid hemorrhage (SAH). Reproducible and controllable animal models that simulate both conditions are presently uncommon. Therefore, new models are needed in order to mimic human pathophysiological conditions resulting from SAH.This report describes the technical nuances of a rabbit blood-shunt SAH model that enables control of intracerebral pressure (ICP). An extracorporeal shunt is placed between the arterial system and the subarachnoid space, which enables examiner-independent SAH in a closed cranium. Step-by-step procedural instructions and necessary equipment are described, as well as technical considerations to produce the model with minimal mortality and morbidity. Important details required for successful surgical creation of this robust, simple and consistent ICP-controlled SAH rabbit model are described.  相似文献   
994.
995.
A gas chromatographic–mass spectrometric method was developed for the enantioselective analysis of levetiracetam and its enantiomer (R)-α-ethyl-2-oxo-pyrrolidine acetamide in dog plasma and urine. A solid-phase extraction procedure was followed by gas chromatographic separation of the enantiomers on a chiral cyclodextrin capillary column and detection using ion trap mass spectrometry. The fragmentation pattern of the enantiomers was further investigated using tandem mass spectrometry. For quantitative analysis three single ions were selected from the enantiomers, enabling selected ion monitoring in detection. The calibration curves were linear from 1 μM to 2 mM for plasma samples and from 0.5 mM to 38 mM for urine samples. In plasma and urine samples the inter-day precision, expressed as relative standard deviation was around 10% in all concentrations. Selected ion monitoring mass spectrometry is suitable for quantitative analysis of a wide concentration range of levetiracetam and its enantiomer in biological samples. The method was successfully applied to a pharmacokinetic study of levetiracetam and (R)-α-ethyl-2-oxo-pyrrolidine acetamide in a dog.  相似文献   
996.
通过SPSepharose,DNA纤维素和磷酸纤维素等柱层析 ,从极端嗜热古菌———芝田硫化叶菌 (Sulfolobusshibatae)中纯化得到分子量为 11.5ku的DNA结合蛋白Ssh12 .Ssh12约占细胞总蛋白的 4% .该蛋白既能与负超螺旋DNA也能与松弛DNA结合 .利用含单切刻环状DNA进行的切刻闭合分析表明 ,Ssh12在与DNA结合时能够固定负超螺旋 .这种能力在室温 ( 2 2℃ )下很弱 ,而在 3 7℃以上则大大增强 .Ssh12的细胞内含量和固定负超螺旋的能力提示 ,该蛋白对于芝田硫化叶菌染色体DNA的组织以及热稳定性起着重要作用 .  相似文献   
997.
Human immunodeficiency virus type 1 (HIV-1) amino acid substitutions observed during antiretroviral drug therapy may be caused by drug selection, non-drug-related evolution, or sampling error introduced by the sequencing process. We analyzed HIV-1 sequences from 371 untreated patients and from 178 patients receiving a single protease inhibitor. Amino acid substitution patterns during treatment were compared with inferred substitution patterns arising evolutionarily without treatment. Our results suggest that most treatment-associated amino acid substitutions are caused by selective drug pressure, including substitutions not previously associated with drug resistance.  相似文献   
998.
The reaction rate and selectivity of the enzymatic kinetic resolution of ibuprofen and 1-phenylethanol with supercritical CO2 as solvent were studied in a batch reactor from 40 °C to 160 °C. The commercial enzyme, Novozym 435, remained partly active for at least 14 h up to 140 °C at 15 MPa. The maximum reaction rate for the esterification of 1-phenylethanol and ibuprofen was at about 90 °C. The enantiomeric excess for 1-phenylethanol exceeds 99% and was temperature independent. Selectivity for ibuprofen esterification reached a lower enantiomeric excess of 61% caused by equilibrium adjustment. The results show that with supercritical CO2 as reaction medium enzymes remain active above 100 °C.  相似文献   
999.
Recent molecular studies revealed nine to ten gene products involved infunction/assembly of the methanoarchaeal ATPase and unravel a closerelationship of the A1A0-ATPase and theV1V0-ATPase with respect to subunit composition and thestructure of individual subunits. Most interestingly, there is anastonishing variability in the size of the proteolipids in methanoar chaealA1A0-ATPases with six, four, or two transmembranehelices and a variable number of conserved protonizable groups per monomer.Despite the structural similarities the A1A0-ATPasediffers fundamentally from the V1V0-ATPase by itsability to synthesize ATP, a feature shared withF1F0-ATPases. The discovery of duplicated andtriplicated versions of the proteolipid in A1A0-ATPsynthases questions older views of the structural requirements for ATPsynthases versus ATP hydrolases and sheds new light on the evolutionof these secondary energy converters.  相似文献   
1000.
Release of large amounts of citric acid from specialized root clusters (proteoid roots) of phosphorus (P)-deficient white lupin (Lupinus albus L.) is an efficient strategy for chemical mobilization of sparingly available P sources in the rhizosphere. The present study demonstrates that increased accumulation and exudation of citric acid and a concomitant release of protons were predominantly restricted to mature root clusters in the later stages of P deficiency. Inhibition of citrate exudation by exogenous application of anion-channel blockers such as ethacrynic- and anthracene-9-carboxylic acids may indicate involvement of an anion channel. Phosphorus-deficiency-induced accumulation and subsequent exudation of citric acid seem to be a consequence of both increased biosynthesis and reduced metabolization of citric acid in the proteoid root tissue, indicated by increased in-vitro activity and enzyme protein levels of phosphoenolpyruvate carboxylase (EC 4.1.1.31), and reduced activity of aconitase (EC 4.2.1.3) and root respiration. Similar to citric acid, acid phosphatase, which is secreted by roots and involved in the mobilization of the organic soil P fraction, was released predominantly from proteoid roots of P-deficient plants. Also 33Pi uptake per unit root fresh-weight was increased by approximately 50% in juvenile and mature proteoid root clusters compared to apical segments of non-proteoid roots. Kinetic studies revealed a K m of 30.7 μM for Pi uptake of non-proteoid root apices in P-sufficient plants, versus K m values of 8.5–8.6 μM for non-proteoid and juvenile proteoid roots under P-deficient conditions, suggesting the induction of a high-affinity Pi-uptake system. Obviously, P-deficiency-induced adaptations of white lupin, involved in P acquisition and mobilization of sparingly available P sources, are predominantly confined to proteoid roots, and moreover to distinct stages during proteoid root development. Received: 10 September 1998 / Accepted: 22 December 1998  相似文献   
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