旋具旋杆镀铬发黑双色工艺

目前,国内的螺钉旋具产品,品种虽然繁多,但在旋杆的表面处理方面,却没有新的突破。为实现一支旋杆具有两种顏色的保护层(不包括喷涂漆之类的处理方法)的设想,我们进行了反复试验,取得了令人满意的结果,现将有关工艺及技术措施介绍如下。一、镀前处理、镀层组合和镀铬工艺选择 1.在镀之前。

旋杆贴标机旋杆过程对注射用水针剂密封性影响研究

注射器是一种常用于临床医学的治疗器械,国家对该产品有严格规定,需对无菌注射器自身密封性进行检测,确保产品质量过关,保证医疗安全。注射器密封性是指容器密封完整性,生产过程中保证密封完整性,避免内容物损失,微生物、气体等其他物质进入污染,保证注射器符合临床安全使用原则。安全性注射器构造繁琐,生产过程中对配件加工和生产环境具有一定规定,安装条件苛刻,实现大批量生产难度系数较高。注射器产品使用贴标机进行生产,注射器包括装有液料粉料的针筒和针杆构成,贴标机过渡转盘将针杆与针筒以不同高度上料,转移至转轮主体上,夹爪抓住针杆,准确预判,将针杆装至针筒内,经过贴标机旋杆活动,针筒与针杆向相反方向旋转,拧紧装配,最后经旋转,由贴标机实现自动贴标,注射器成品产生。

Variable-based Ramberg-Osgood constitutive model of power spinning bushing

The influences of power spinning process parameters on the mechanical properties of spinning parts were analyzed with an SXD100/3-CNC numerical control power spinning machine.The unidirectional tensile tests were carried out.Based on the experimental data,a ternary quadratic regression equation was established by orthogonal experiment.The Ramberg-Osgood constitutive model of tin-bronze connecting rod bushing was obtained.Referred to the constitutive relation of macroscopic incremental,the incremental elastoplastic constitutive relation of spinning parts was deduced based on the Mises yield criterion and kinematic hardening model.The results can be applied to the elastoplastic analysis in finite element numerical simulation.

二段成型机带束层供料车改进与应用

随着公司生产规模的不断扩大,二段成型机上的带束层供料小车的缺陷特别突出。该文结合杠杆结构原理和凸轮结构限位原理及在实践工作中的经验,采取了改原来固定式方钢轴承座支撑工字轮为杠杆式摆臂结构支撑工字轮,简化了工字轮装卸支撑结构和刹车机构,最终解决了缺陷问题,降低了成本,提高了效率。

Numerical Simulations of Polymer Melt Conveying in Co-Rotating Twin Screw Extruder

The 3 D non isothermal flow of non Newtonian viscous polymer melt in a co rotating twin screw extruder is modeled. The distributions of the velocity, temperature, pressure and the viscous dissipation in the flow domain are presented by using a fluid dynamics analysis package (Polyflow). The numerical results show that the temperatures are high in the intermeshing region and on the screw surface, the maximum pressure and the minimum pressure occur in the intermeshing region, and the flow rate is almost proportional to the screw speed.

Adjuvant probiotics improve the eradication effect of triple therapy for Helicobacter pylori infection

AIM:To investigate whether the addition of probiotics can improve the eradication effect of triple therapy for Helicobacter pylori (H. pylori ) infection. METHODS:This open randomized trial recruited 234 H. pylori positive gastritis patients from seven local centers. The patients were randomized to one-week standard triple therapy (omeprazole 20 mg bid , clarithromycin 500 mg bid , and amoxicillin 1000 mg bid ; OCA group, n = 79); two weeks of pre-treatment with probiotics, containing 3 × 107 Lactobacillus acidophilus per day, prior to one week of triple therapy (POCA group, n = 78); or one week of triple therapy followed by two weeks of the same probiotics (OCAP group, n = 77). Successful eradication was defined as a negative C13 or C14 urease breath test four weeks after triple therapy. Patients were asked to report associated symptoms at baseline and during follow-up, and side effects related to therapy were recorded. Data were analyzed by both intention-to-treat (ITT) and per-protocol (PP) methods. RESULTS:PP analysis involved 228 patients, 78 in the OCA, 76 in the POCA and 74 in the OCAP group. Successful eradication was observed in 171 patients; by PP analysis, the eradication rates were significantly higher (P = 0.007 each) in the POCA (62/76; 81.6%, 95% CI 72.8%-90.4%) and OCAP (61/74; 82.4%, 95% CI 73.6%-91.2%) groups than in the OCA group (48/78; 61.5%, 95% CI 50.6%-72.4%). ITT analysis also showed that eradication rates were significantly higher in the POCA (62/78; 79.5%, 95% CI 70.4%-88.6%) and OCAP (61/77; 79.2%, 95% CI 70%-88.4%) groups than in the OCA group (48/79; 60.8%, 95% CI 49.9%-71.7%), (P = 0.014 and P = 0.015). The symptom relieving rates in the POCA, OCAP and OCA groups were 85.5%, 89.2% and 87.2%, respectively. Only one of the 228 patients experienced an adverse reaction. CONCLUSION:Administration of probiotics before or after standard triple therapy may improve H. pylori eradication rates.

Causal role of Helicobacter pylori infection in gastric cancer

Gastric cancer is the second most frequent cancer in the world, accounting for a large proportion of all cancer cases in Asia, Latin America, and some countries in Europe. Helicobacter pylori（H pylori） is regarded as playing a specific role in the development of atrophic gastritis, which represents the most recognized pathway in multistep intestinal-type gastric carcinogenesis. Recent studies suggest that a combination of host genetic factors, bacterial virulence factors, and environmental and lifestyle factors determine the severity of gastric damage and the eventual clinical outcome of H pylori infection. The seminal discovery of Hpylori as the leading cause of gastric cancer should lead to effective eradication strategies. Prevention of gastric cancer requires better screening strategies to identify candidates for eradication.

Quality of ulcer healing in gastrointestinal tract:Its pathophysiology and clinical relevance

In this paper, we review the concept of quality of ulcer healing （QOUH） in the gastrointestinal tract and its role in the ulcer recurrence. In the past, peptic ulcer disease （PUD） has been a chronic disease with a cycle of repeated healing/remission and recurrence. The main etiological factor of PUD is Helicobacter pylori （H. pylorl~, which is also the cause of ulcer recur- rence. However, H. pylori-negative ulcers are pres- ent in 12%-20% of patients; they also recur and are on occasion intractable. QOUH focuses on the fact that mucosal and submucosal structures within ulcer scars are incompletely regenerated. Within the scars of healed ulcers, regenerated tissue is immature and with distorted architecture, suggesting poor QOUH. The abnormalities in mucosal regeneration can be the basis for ulcer recurrence. Our studies have shown that persistence of macrophages in the regenerated area plays a key role in ulcer recurrence. Our studies in a rat model of ulcer recurrence have indicated that proinflammatory cytokines trigger activation of macro- phages, which in turn produce increased amounts of cytokines and chemokines, which attract neutrophils to the regenerated area. Neutrophils release proteolytic enzymes that destroy the tissue, resulting in ulcer re- currence. Another important factor in poor QOUH can be deficiency of endogenous prostaglandins and a defi- ciency and/or an imbalance of endogenous growth fac- tors. Topically active mucosal protective and antiulcer drugs promote high QOUH and reduce inflammatory cell infiltration in the ulcer scar. In addition to PUD, the concept of QOUH is likely applicable to inflammatory bowel diseases including Crohn＇s disease and ulcer- ative colitis.

E-cadherin in gastric cancer

Cadherin is an adhesion molecule and a superfamily of calcium-mediated membrane glycoproteins. E-cadherin is the prototype of the class E-cadherin that links to catenins to form the cytoskeleton. Recent evidence has shown that E-cadherin not only acts as an adhesive, but also plays important roles in growth development and carcinogenesis. It has been recently viewed as an invasion as well as a growth suppressor gene. This review summarizes the recent discoveries on E-cadherin and its role in gastric cancer. In particular, our work on E-cadherin in gastric cancer, including its relation with Helicobacter pylori and clinical applications, are described in detail.

Autoimmune thyroid diseases and Helicobacter pylori: The correlation is present only in Graves's disease

AIM: To investigate the correlation between autoimmune thyroid diseases (ATDs) and the prevalence of Cag-A positive strains of Helicobacter pylori (H. pylori) in stool samples. METHODS: We investigated 112 consecutive Caucasian patients (48 females and 4 males with Graves' disease and 54 females and 6 males with Hashimoto' s thyroiditis HT), at their first diagnosis of ATDs. We tested for H. pylori in stool samples using an amplified enzyme immunoassay and Cag-A in serum samples using an enzyme-linked immunoassay method (ELISA). The results were analyzed using the two-sided Fisher' s exact test and the respective odds ratio (OR) was calculated. RESULTS: A marked correlation was found between the presence of H. pylori (P ≤ 0.0001, OR 6.3) and, in particular, Cag-A positive strains (P ≤ 0.005, OR 5.3)in Graves' disease, but not in Hashimoto's thyroiditis, where we found only a correlation with Cag-A strains (P ≤ 0.005, OR 8.73) but not when H. pylori was present. CONCLUSION: The marked correlation between H. pylori and Cag-A, found in ATDs, could be dependent on the different expression of adhesion molecules in the gastric mucosa.

Association of CagA and VacA presence with ulcer and non-ulcer dyspepsia in a Turkish population

AIM:The mostly known genotypic virulence features,of H.pylori are cytotoxin associated gene A (cagA) and Vacuolating cytotoxin gene A (VacA).We investigated the association of these major virulence factors with ulcer and non-ulcer dyspepsia in our region. METHODS:One hundred and forty two dyspeptic patients were studied (average age 44.8±15.9 years,range 15-87 years,64 males and 78 females).Antral and corpus biopsies were taken for detecting and genotyping of H.pylori.107 patients who were H.pylori positive by histological assessment were divided into three groups according to endoscopic findings:Duodenal ulcer (DU),gastric ulcer (GU) and non-ulcer dyspepsia (NUD).The polymerase chain reaction (PCR) was used to detect CagA and VacA genes of H.pylori using specific primers. RESULTS:H.pyloriwas isolated from 75.4% (107/142) of the patients.Of the 107 patients,66 (61.7%) were cagA- positive and 82 (76.6%) were VacA-positive.CagA gene was positively associated with DU and GU (P<0.01,P<0.02), but not with NUD (P>0.05).Although VacA positivity in ulcer patients was higher than that in NUD group,the difference was not statistically significant (P>0.05). CONCLUSION:There is a significantly positive association between CagA genes and DU and GU.The presence of VacA is not a predictive marker for DU,GU,and NUD in our patients.

Factors predicting survival in patients with proximal gastric carcinoma involving the esophagus

AIM： To investigate the clinicopathologic features which predict surgical overall survival in patients with proxima gastric carcinoma involving the esophagus （PGCE）. METHODS： Electronic pathology database established in the Department of Pathology of the Nanjing Drum Tower Hospital was searched for consecutive resection cases of proximal gastric carcinoma over the period from May 2004 through July 2009. Each retrieved pa- thology report was reviewed and the cases with tumors crossing the gastroesophageal junction line were se- lected as PGCE. Each tumor was re-staged, following the guidelines on esophageal adenocarcinoma, accord- ing to the 7th edition of the American Joint Commission on Cancer Staging Manual. All histology slides were studied along with the pathology report for a retrospec- tive analysis of 13 clinicopathologic features, i.e., age, gender, Helicobacter pylori （H. pylon} infection, surgical modality, Siewert type, tumor Bormann＇s type, size, dif- ferentiation, histology type, surgical margin, lympho- vascular and perineural invasion, and pathologic stage in relation to survival after surgical resection. Prognos- tic factors for overall survival were assessed with uni- and multi-variate analyses. RESULTS： Patients＇ mean age was 65 years （range： 47-90 years）. The male： female ratio was 3.3. The 1-, 3- and 5-year overall survival rates were 87%, 61% and 32%, respectively. By univariate analysis, age, male gender, H. pylori, tumor Bormann＇s type, size, histology type, surgical modality, positive surgical margin, lym- phovascular invasion, and pT stage were not predictive for overall survival; in contrast, perineural invasion （P = 0.003）, poor differentiation （P = 0.0003）, 〉 15 to- tal lymph nodes retrieved （P = 0.008）, positive lymph nodes （P = 0.001）, and distant metastasis （P = 0.005） predicted poor post-operative overall survival. Celiac axis nodal metastasis was associated with significantly worse overall survival （P = 0.007）. By multivariate analysis, ≥ 16 positive nodes （P = 0.018）, lymph node ratio 〉 0.2 （P = 0.003）, and overall pathologic stage （P= 0.002） were independent predictors for poor overa survival after resection. CONCLUSION： Patients with PGCE showed worse over- all survival in elderly, high nodal burden and advanced pathologic stage. This cancer may be more accurately staged as gastric, than esophageal, cancer.

CD74 in antigen presentation,inflammation,and cancers of the gastrointestinal tract

CD74 is a protein whose initial role in antigen presentation was recognized two decades ago. Recent studies have revealed that it has additional functions as a receptor for macrophage migration inhibitory factor and as a receptor for an important human pathogen, Helicobacter pylori （H pylon）. The role of CD74 as a receptor is important because after binding of migration inhibitory factor or H pylori, NF-κB and Erkl/2 activation occurs, along with the induction of proinflammatory cytokine secretion. This review provides an up-to-date account of the functions of CD74 and how it might be involved in inflammation and cancer within the gastrointestinal tract.

CpG island methylator phenotype and Helicobacter pylori infection associated with gastric cancer

AIM： To investigate the association between the CpG island methylator phenotype （CIMP） and serum Helico- bacter pylori （H. pylori） levels for clinical prediction of gastric cancer （GC） progression. METHODS： We analyzed the serum ClMP status of 75 patients with GC using a methylation marker panel and a methylation-specific polymerase chain reaction. Serum samples from 40 healthy persons were examined at the same time. The genes examined were APC, WIF-1, RUNX-3, DLC-1, SFRP-1, DKK and E-cad. H. pylori infec- tion in serum was assayed with an anti-H, pylori immu- noglobulin G antibody test and a rapid urease test. RESULTS： The frequencies of high-level methylation in GC tissues for the seven genes were： 48% for APC, 57.33% for WIF-1, 56% for RUNX-3, 50.67% for DLC-1, 52% for SFRP-1, 54.67% for DKK, and 48% for E-cad.The frequencies in GC serum were 30.67% for APC, 34.67% for WIF-1, 37.33% for RUNX-3, 29.33% for DLC-1, 33.33% for SFRP-1, 32% for DKK, and 26.67% for E-cad. CIMP＋ （defined as ≥ 3 methylated genes） was associated with 47 （62.67%） GC tissue samples and 44 （58.67%） GC serum samples. CIMP＋ was not associated with non-neoplastic mucosal tissues or the serum of healthy persons. Of the 75 GC cases, 51 （68%） were H. pylori＋, and 24 （32%） were H. pylori-. Of the 51 H. pylori＋ cases, 36 were CIMP＋ and 15 were CIMP-. In contrast, for the 24 H. pylori- cases, 11 were CIMP＋, and 13 were CIMP-. The difference was signifi- cant between the H. pylori＋ and H. pylori- groups χ2 = 4.27, P 〈 0.05）. Of the 51 H. pylori＋ GC patients, 34 were CIMP＋ and 17 were CIMP-, while among the 24 H. pylori- GC cases, 10 were CIMP＋ and 14 were CIMP-. The difference was significant between the H. pylori＋ and H. pylori- groups （χ2 = 4.21, P 〈 0.05）. A 2-year follow-up showed significant difference in the rates of metastasis and recurrence between H. pylori＋/CIMP＋ cases and the H. pylori＋/CIMP- cases or CIMP- cases associated with H. pylori assayed in serum （P 〈 0.05）. However, there were no significant differences in sur- vival rates between the two groups. CONCLUSION： H. pylori＋/CIMP＋ cases are associ- ated with higher rates of metastasis and recurrence thanH, pylori＋/CIMP- cases. Serum may be useful for examining CIMP status.

Comparison of sequential and 7-,10-,14-d triple therapy for Helicobacter pylori infection

AIM:To compare the effectiveness of sequential therapy for Helicobacter pylori(H.pylori) infection with that of triple therapy of varying durations.METHODS:The 460 patients enrolled in this study had H.pylori-associated gastritis or a gastric or duodenal ulcer.After screening,H.pylori-infected patients were randomly assigned to receive either conventional triple therapy for 7,10 or 14 d,or a new 10-d sequential therapy.Each of the 4 treatment groups included 115 patients.The outcomes of eradication therapy were assessed 4 wk after treatment by the urea breath test and histology.RESULTS:The overall eradication rate was 81.0%,and eradication rates were 75.7% for 7-d conventional triple therapy,81.9% for 10-d conventional triple therapy,84.4% for 14-d conventional triple therapy,and 82.0% for 10-d sequential therapy.Neither intention-to-treat analysis nor per protocol analysis showed significant differences in eradication rates using sequential therapy or the standard triple therapy(P = 0.416 and P = 0.405,respectively).CONCLUSION:There are no significant differences between 10-d sequential eradication therapy for H.pylori and any duration of standard triple treatment in Korean patients.

Furazolidone therapy for Helicobacter pylori:Is it effective and safe?

Some aspects related with the use of furazolidone as a rescue therapy for Helicobacter pylori （H pylorl） infection should be remarked, especially regarding its potential oncologic risk. The inclusion of furazolidone in a treatment regimen for H pylori infection is, at least, controversial, and it does not appear to be safe.

Levofloxacin/amoxicillin-based schemes vs quadruple therapy for Helicobacter pylori eradication in second-line

Worldwide prevalence of Helicobacter pylori(H.pylori) infection is approximately 50%,with the highest being in developing countries.We compared cure rates and tolerability(SE) of second-line anti-H.pylori levofloxacin/amoxicillin(LA)-based triple regimens vs standard quadruple therapy(QT).An English language literature search was performed up to October 2010.A meta-analysis was performed including randomized clinical trials comparing 7-or 10-d LA with 7-d QT.In total,10 articles and four abstracts were identified.Overall eradication rate in LA was 76.5%(95% CI:64.4%-97.6%).When only 7-d regimens were included,cure rate was 70.6%(95% CI:40.2%-99.1%),whereas for 10-d combinations,cure rate was significantly higher(88.7%;95% CI:56.1%-109.9%;P < 0.05).Main eradication rate for QT was 67.4%(95% CI:49.7%-67.9%).The 7-d LA and QT showed comparable efficacy [odds ratio(OR):1.09;95% CI:0.63-1.87],whereas the 10-d LA regimen was significantly more effective than QT(OR:5.05;95% CI:2.74-9.31;P < 0.001;I 2 = 75%).No differences were reported in QT eradication rates among Asian and European studies,whereas LA regimens were more effective in European populations(78.3% vs 67.7%;P = 0.05).Incidence of SE was lower in LA therapy than QT(OR:0.39;95% CI:0.18-0.85;P = 0.02).A higher rate of side effects was reported in Asian patients who received QT.Our findings support the use of 10-d LA as a simple second-line treatment for H.pylori eradication with an excellent eradication rate and tolerability.The optimal second-line alternative scheme might differ among countries depending on quinolone resistance.