In this task, you are given an abstract of article. Your task is to generate title for this article. Preferred titles are under thirty words.

[Q]: PURPOSE Anticoagulant prophylaxis in patients with central venous catheters is controversial. We performed a meta-analysis of randomized controlled trials of anticoagulant prophylaxis in patients with central venous catheters.
METHODS MEDLINE and EMBASE were searched up to May 2006, supplemented by manual searches of conference proceedings and bibliographies.
RESULTS Fifteen trials were included. Unfractionated heparin infusion, oral fixed low-dose vitamin K antagonist, and subcutaneous low-molecular-weight heparin were evaluated. For all catheter-associated deep vein thrombosis (symptomatic and asymptomatic combined), the summary relative risks ranged from 0.31 to 0.73 (all achieved statistical significance). For symptomatic deep vein thrombosis, the summary relative risks ranged from 0.28 to 0.72, but did not achieve statistical significance for any individual regimen.
CONCLUSION Anticoagulant prophylaxis is effective for preventing all catheter-associated deep vein thrombosis in patients with central venous catheters. The effectiveness for preventing symptomatic venous thromboembolism, including pulmonary embolism, remains uncertain.
[A]: Prevention of central venous catheter-associated thrombosis: a meta-analysis.

[Q]: BACKGROUND In the plant sciences there are two widely applied technologies for measuring nuclear DNA content: Feulgen absorbance cytophotometry and flow cytometry (FCM). While FCM is, with good reasons, increasingly popular among plant scientists, absorbance-cytophotometric techniques lose ground. This results in a narrowing of the methodological repertoire, which is neither desirable nor beneficial. Both approaches have their advantages, but static cytophotometry seems to pose more instrumental difficulties and material-based problems than FCM, so that Feulgen-based data in the literature are often less reliable than one would expect. SCOPE The purpose of this article is to present a selective overview of the field of nuclear DNA content measurement, and C-values in particular, with a focus on the technical difficulties imposed by the characteristics of the biological material and with some comments on the photometrical aspects of the work. For over 20 years it has been known that plant polyphenols cause problems in Feulgen DNA cytophotometry, since they act as major staining inhibitors leading to unreliable results. However, little information is available about the chemical classes of plant metabolites capable of DNA staining interference and the mechanisms of their inhibition. Plant slimes are another source of concern.
CONCLUSIONS In FCM research to uncover the effects of secondary metabolites on measurement results has begun only recently. In particular, the analysis of intraspecific genome size variation demands a stringent methodology which accounts for inhibitors. FCM tests for inhibitory effects of endogenous metabolites should become obligatory. The use of dry seeds for harvesting embryo and endosperm nuclei for FCM and Feulgen densitometry may often provide a means of circumventing staining inhibitors. The importance of internal standardization is highlighted. Our goal is a better understanding of phytochemical/cytochemical interactions in plant DNA photometry for the benefit of an ever-growing list of plant genome sizes.
[A]: Cytochemistry and C-values: the less-well-known world of nuclear DNA amounts.

[Q]: OBJECTIVE To systematically review the evidence that smoking cessation after diagnosis of a primary lung tumour affects prognosis.
DESIGN Systematic review with meta-analysis.
DATA SOURCES CINAHL (from 1981), Embase (from 1980), Medline (from 1966), Web of Science (from 1966), CENTRAL (from 1977) to December 2008, and reference lists of included studies. STUDY SELECTION Randomised controlled trials or observational longitudinal studies that measured the effect of quitting smoking after diagnosis of lung cancer on prognostic outcomes, regardless of stage at presentation or tumour histology, were included.
DATA EXTRACTION Two researchers independently identified studies for inclusion and extracted data. Estimates were combined by using a random effects model, and the I(2) statistic was used to examine heterogeneity. Life tables were used to model five year survival for early stage non-small cell lung cancer and limited stage small cell lung cancer, using death rates for continuing smokers and quitters obtained from this review.
RESULTS In 9/10 included studies, most patients studied were diagnosed as having an early stage lung tumour. Continued smoking was associated with a significantly increased risk of all cause mortality (hazard ratio 2.94, 95% confidence interval 1.15 to 7.54) and recurrence (1.86, 1.01 to 3.41) in early stage non-small cell lung cancer and of all cause mortality (1.86, 1.33 to 2.59), development of a second primary tumour (4.31, 1.09 to 16.98), and recurrence (1.26, 1.06 to 1.50) in limited stage small cell lung cancer. No study contained data on the effect of quitting smoking on cancer specific mortality or on development of a second primary tumour in non-small cell lung cancer. Life table modelling on the basis of these data estimated 33% five year survival in 65 year old patients with early stage non-small cell lung cancer who continued to smoke compared with 70% in those who quit smoking. In limited stage small cell lung cancer, an estimated 29% of continuing smokers would survive for five years compared with 63% of quitters on the basis of the data from this review.
CONCLUSIONS This review provides preliminary evidence that smoking cessation after diagnosis of early stage lung cancer improves prognostic outcomes. From life table modelling, the estimated number of deaths prevented is larger than would be expected from reduction of cardiorespiratory deaths after smoking cessation, so most of the mortality gain is likely to be due to reduced cancer progression. These findings indicate that offering smoking cessation treatment to patients presenting with early stage lung cancer may be beneficial.
[A]:
Influence of smoking cessation after diagnosis of early stage lung cancer on prognosis: systematic review of observational studies with meta-analysis