***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: In the Sh and ong Intervention Trial , 2 weeks of antibiotic treatment for Helicobacter pylori reduced the prevalence of precancerous gastric lesions , whereas 7.3 years of oral supplementation with garlic extract and oil ( garlic treatment ) or vitamin C , vitamin E , and selenium ( vitamin treatment ) did not . Here we report 14.7-year follow-up for gastric cancer incidence and cause-specific mortality among 3365 r and omly assigned subjects in this masked factorial placebo-controlled trial . Conditional logistic regression was used to estimate the odds of gastric cancer incidence , and the Cox proportional hazards model was used to estimate the relative hazard of cause-specific mortality . All statistical tests were two-sided . Gastric cancer was diagnosed in 3.0 % of subjects who received H pylori treatment and in 4.6 % of those who received placebo ( odds ratio = 0.61 , 95 % confidence interval = 0.38 to 0.96 , P = .032 ) . Gastric cancer deaths occurred among 1.5 % of subjects assigned H pylori treatment and among 2.1 % of those assigned placebo ( hazard ratio [ HR ] of death = 0.67 , 95 % CI = 0.36 to 1.28 ) . Garlic and vitamin treatments were associated with non-statistically significant reductions in gastric cancer incidence and mortality .  Vitamin treatment was associated with statistically significantly fewer deaths from gastric or esophageal cancer , a secondary endpoint ( HR = 0.51 , 95 % CI = 0.30 to 0.87 ; P = .014 ) BACKGROUND Helicobacter pylori is associated with gastrointestinal diseases such as gastritis , peptic ulcers , malignancy and lymphoma , and extra-gastrointestinal conditions . H. pylori infection is negatively associated with children 's growth . Chronic inflammation of the stomach that results in the loss of appetite and , dysregulation of neuroendocrine hormones such as leptin , and ghrelin are the probable reasons of this negative association . The objective of this study is to determine the serum levels of leptin , ghrelin , and IGF-1 in H. pylori-infected children and their relations with growth . MATERIAL S AND METHODS A hundred and sixty-one school children aged between 6 and 14 years were selected r and omly from five primary schools representing a cross section of population . Demographic and sociocultural characteristics , and anthropometric measurements were recorded . Serum H. pylori IgG , insulin-like growth factor-1 , leptin , and ghrelin levels were measured in all children . The children were grouped according to the nutritional status and Helicobacter pylori seropositivity . Nutritional indices were compared among groups in association with serum leptin , ghrelin , and insulin-like growth factor-1 levels . RESULTS H. pylori IgG positivity was found in 34.2 % , and 14.9 % of children were malnourished . H. pylori seropositivity was significantly higher in older ages ( 10.32 ± 2.26 vs 9.53 ± 2.36 years , p = .036 ) , and body weight and height Z scores were significantly lower in H. pylori-seropositive children ( -0.33 ± 1.08 vs 0.04 ± 1.26 , p = .044 and 0.13 ± 0.92 vs 0.23 ± 0.91 , p = .018 respectively ) . H. pylori seropositivity was found to be an independent risk factor for shorter body height ( p = .01 ) . Serum leptin , ghrelin , and IGF-1 levels were not associated with H. pylori IgG seropositivity ( 0.35 vs 0.55 ng/mL , p = .3 ; 3267.4 ± 753.0 vs 2808.3 ± 911.4 pg/mL , p = .06 ; 470 ± 176 vs 521 ± 179 ng/mL , p = .32 , respectively ) . CONCLUSIONS Children infected with H. pylori are prone to short stature . This effect seems to be independent of neuroendocrine hormones Objective : There have been a number of reports that natural foods such as garlic , honey , and capsaicin can inhibit Helicobacter pylori in vitro and each report has suggested the natural ingredient be used for treatment of the infection . We investigated whether garlic or capsaicin-containing peppers would actually inhibit H. pylori in vivo . Methods : We performed a prospect i ve crossover study in healthy H. pylori-infected adults . We used the urea breath test to assess the status of the H. pylori infection . On separate days subjects received three test meals consisting of beef , tortillas , and salad with one of the following : fresh garlic ( 10 sliced cloves ) , capsaicin ( six sliced fresh jalapeños ) , two tablets of bismuth subsalicylate ( Pepto-Bismol , positive control ) , or nothing added ( negative control ) . Breath testing was done before the first meal , the evening meal , and the following morning . At least 2 days elapsed between the test substances . Results : Twelve subjects participated ( seven men , five women ) , with an average age of 41.4 yr , range 27–51 yr . Ten subjects received garlic , six received jalapeños , and 11 received bismuth . Neither garlic nor capsaicin had any in vivo effect on H. pylori ( median urease activity 28.5 vs 39.8 and 43.7 vs 46.6 before and after garlic and jalapeños , respectively ) p > 0.8 . Bismuth had a marked inhibitory effect ( median 55.8 vs 14.3 before and after bismuth ) p < 0.001 , respectively . Conclusions : This study did not support a role for either garlic or jalapeños in the treatment of H. pylori infection . Caution must be used when attempting to extrapolate data from in vitro studies to the in vivo condition Non-r and omised studies of the effects of interventions are critical to many areas of healthcare evaluation , but their results may be biased . It is therefore important to underst and and appraise their strengths and weaknesses . We developed ROBINS-I ( “ Risk Of Bias In Non-r and omised Studies - of Interventions ” ) , a new tool for evaluating risk of bias in estimates of the comparative effectiveness ( harm or benefit ) of interventions from studies that did not use r and omisation  to allocate units ( individuals or clusters of individuals ) to comparison groups . The tool will be particularly useful to those undertaking systematic review s that include non-r and omised studies BACKGROUND People have more and more concerned about allitridum as studies have shown that taking more raw garlic associated with a lower risk for cancers of the alimentary system . In the present study , we tried to examine whether a large dose of allitridum and a microdose of selenium prevent gastric cancer . METHODS A double-blind intervention study was performed on the participants aged ( 35 - 74 ) years , who had matched at least one of the following criteria : ( 1 ) a medical history of stomach disorder , ( 2 ) a family history of tumour , or ( 3 ) smoking and /or alcohol consumption . A total of 2,526 and 2,507 persons were r and omly enrolled into intervention group and control group respectively from 288 natural villages of seven communities in Qixia County , Sh and ong Province , China . Each person of the intervention group orally took 200 mg synthetic allitridum every day and 100 microg selenium every other day for one month of each year during November 1989 to December 1991 . At the same time , people in control group were given 2 placebo capsules containing corn oid with the identical appearance to that in the intervention group . RESULTS For all subjects the large dose of allitridum was accepted and no harmful side effects were found during the study . In the first follow-up five years ( 1992 - 1997 ) after stopping the intervention , the morbidity rates of malignant tumours in the intervention group declined by 22 % , in contrast to the control group , declined by 47.3 % . After adjusting for age , gender , and other potential confounders , relative risks ( RRs ) for all tumours and gastric cancer of the whole population were 0.67 ( 95 % CL : 0.43 - 1.03 ) and 0.48 ( 95 % CL : 0.21 - 1.06 ) , respectively , and for male group they were 0.51 ( 95 % CL : 0.30 - 0.85 ) and 0.36 ( 95 % CL : 0.14 - 0.92 ) , respectively . No signigicantly protective effect was found for the female subgroup . CONCLUSION The present study proves that large doses of allitridum and microdorse of selenium may effectively prevent gastric cancer  , especially in men In this study , in vivo effectiveness of ascorbic acid ( AA ) , beta carotene ( BC ) and allicin in HP eradication were evaluated . 210 patients who are HP positive in biopsy were involved in this study . The patients r and omised to seven treatment groups ( each group consisting of 30 patients ) . The first group was given st and ard eradication treatment ( lansaprasol 30 mg bid , clarithromycin 500 mg bid , amoxicillin 1 g bid for 14 days ) . Second group received AA 1000 mg/day in addition to the st and ard treatment . Third group received only AA 1000 mg/day for 14 days . Fourth group was treated with st and ard regiment plus 120 mg/day BC . Fifth group was given only BC 120 mg/day for 14 days . Sixth group was given st and ard regiment and allicin 4200 micrograms/day . Seventh group received only Allicin 1200 micrograms/day for 14 days . The eradication was achieved in 20 ( 66.6 % ) in group I , 15 ( 50 % ) in group II , 3 ( 10 % ) in group III , 15 ( 50 % ) in group IV , 0 ( 0 % ) in group V , 27 ( 90 % ) in group VI and 7 ( 23.3 % ) in group VII . Allicin seemed to be potentially effective agent for HP eradication but ascorbic acid , beta caroten was found to be ineffective Resistance of Helicobacter pylori to clarithromycin and metronidazole is now found worldwide . Steam‐distilled garlic oil has in vitro activity against H. pylori and may be a useful alternative treatment strategy OBJECTIVE To investigate the prevalence of  Helicobacter pylori ( Hp ) infection in Chengdu and its risk factors . METHODS Permanent residents in Chengdu who took routine health examinations in the West China Hospital of Sichuan University were recruited in the study . All participants received 14C-urea breath test ( 14C-UBT ) for the diagnosis of Hp infection . A r and om sample ( n = 500 ) was drawn for a question naire survey . RESULTS Of 8,365 participants , 53.1 % were diagnosed with Hp infection . Higher prevalence was found in male participants ( 54.1 % ) than in female participants ( 51 . 7 % , P < 0.05 ) . More than half of those older than 30 years old were infected . Of the 500 people who were invited to participate in the question naire survey , 497 returned question naires eligible for analyses . Compared with Han , Tibetans had a higher level of Hp infection ( 74.2 % vs. 48.6 % , P < 0.05 ) . Higher levels of Hp infection were also found in those with vomiting symptoms ( 63.4 % vs. 52.2 % , P < 0.05 ) . The participants who ate raw garlic had a lower level of Hp infection than those who did not eat raw garlic ( 52.6 % vs. 67.9 % , P < 0.05 ) . CONCLUSION The prevalence of Hp infection in Chengdu is high . Male , Tibetan and vomiting symptoms are predictors of Hp infection , while raw garlic seems to reduce the infection Although many case-control studies suggested that garlic intake may reduce gastric cancer risk , evidence from prospect i ve cohort studies has been lacking . We examined the association between garlic intake and subsequent risk of gastric cancer among 77,086 women in the Nurses ' Health Study ( 1984 - 2014 ) and 46,398 men in the Health Professionals Follow-Up Study ( 1986 - 2014 ) .  Relative risks ( RRs ) and 95 % confidence intervals ( 95 % CIs ) were estimated using Cox proportional hazards models . We additionally examined garlic intake in relation to Helicobacter pylori ( H. pylori ) infection among 613 participants using logistic regression . During up to 30 years of follow-up , 292 participants were diagnosed with gastric cancer .  The pooled multivariable RR of gastric cancer among participants who ate garlic , as compared to those who did not , were 1.11 ( 95 % 
    Output:
    
Pooled evidence , mainly from case-control studies , suggested a significant inverse association of garlic intake with gastric cancer risk .
Given the limitations of included studies , current epidemiological evidence is not sufficient to reach any definite conclusion regarding the association of garlic with Helicobacter pylori infection