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BACKGROUND AND AIMS: The efficiency of Helicobacter pylori eradication varies geographically, as do many parameters that might affect therapeutic efficiency, including bacterial genotype. The aim of the present study was to determine the efficiency of H. pylori eradication using a 10-day proton pump inhibitor-based triple-therapy regimen (omeprazole, clarithromycin and amoxycillin) in an eastern Indian patient population, and to find out the relationship, if any, of the success or failure of the therapy to known features of bacterial genotype. METHODS: Helicobacter pylori infections were analyzed in 66 duodenal ulcer patients by upper gastrointestinal endoscopy, rapid urease tests, histology and culture. The cytotoxin-associated gene (cagA) and vacuolating cytotoxin (vacA) gene status of cultured strains were studied by polymerase chain reaction. Treatment was given for 10 days and endoscopy was repeated at 4 and 12 weeks post therapy to monitor ulcer healing and H. pylori eradication. RESULTS: Ulcer healing was observed in 60 patients (96.77%). Helicobacter pylori was eradicated in 41 (62.12% intention to treat, 66.13% per protocol) of the 66 duodenal ulcer patients, but not in the other 25. The bacteria from 47 patients were genotyped. The only significant disease-associated difference in patterns observed was that the vacA m1 allele was represented more disproportionately among patients with eradication failures (68%) than in those with successful eradication (39%) (P < 0.05) No significant association of vacAs1 (signal sequence allele) or cag pathogenicity island status with persistence was detected. CONCLUSIONS: This study highlights the public health need for cheaper, more cost-effective anti-H. pylori therapies for developing countries, and suggests that subtle features of bacterial genotype can influence therapeutic efficiency. The possibility that particular vacA mid region alleles affect persistence, perhaps through toxin action on particular gastric cell types, merits further study.  相似文献   
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Background The vulvar diseases are common skin conditions, but their frequency and importance are often underestimated. Objectives This study is aimed to investigate the frequency and clinical patterns of vulvar diseases and the risk factors associated with these diseases in patients attending a tertiary care hospital in eastern Nepal. Methods Patients with vulval symptoms or cutaneous lesions on the vulva were enrolled in the study. Laboratory investigations were carried out according to need. Equal numbers of age‐matched females without vulval lesions or symptoms were selected from the outpatient department as controls. Results Of 5521 female patients attending the Dermatology Department’s outpatient clinic during the study period, 105 (1.9%) had vulval symptoms and/or lesions. The most common types of vulvar disease were vulvar dermatoses (62.85%), pruritus vulvae (36.19%) and vulvodynia (0.95%). In vulvar dermatoses, infection was the most common (33.4%) manifestation, with a predominance of vulvovaginal candidiasis. Other dermatoses included: cysts and tumors (5.6%); pigmentary changes (vitiligo) (5.6%); inflammatory dermatoses (6.6%); atrophic vaginitis (1.8%); erosive disease (0.9%); and dermatosis caused by sexual abuse (1.9%). Use of nylon undergarments, occasional detergent use for washing clothes, and an irregular menstrual history were found to be associated with vulvar diseases. Conclusions Our study findings indicate that the known frequency of vulvar diseases may represent only a small proportion of actual frequency. Further clinical and population‐based research should be carried out with respect to the treatment, follow‐up, and true prevalence of these diseases in the community.  相似文献   
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维生素K3粉末降解动力学   总被引:1,自引:0,他引:1  
在温度为50~90℃,相对湿度为50~93%范围内,维生素K3的变色速率方程为—dR/dt=kRR,降解速率方程为d(Co—c)/dt=kC(co—c)1/2,光解速率方程为—dR/dt=kP(Ro—R)-1。kRC与热力学温度T和相对湿度RH的关系通式为k=k′exp(—EA/RT)exp(m′RH)。在实验温度和湿度范围内,变色和降解的表观活化能平均值分别为105.51和130.72 kJ/mol。  相似文献   
15.

Background

Gastroesophageal reflux disease (GERD) and its complications are thought to be infrequent in India; there are no data from India on the prevalence of and risk factors for GERD. The Indian Society of Gastroenterology formed a task force aiming to study: (a) the frequency and profile of GERD in India, (b) factors including diet associated with GERD.

Methods

In this prospective, multi-center (12 centers) study, data were obtained using a questionnaire from 3224 subjects regarding the frequency, severity and duration of heartburn, regurgitation and other symptoms of GERD. Data were also obtained regarding their dietary habits, addictions, and lifestyle, and whether any of these were related or had been altered because of symptoms. Data were analyzed using univariate and multivariate methods.

Results

Two hundred and forty-five (7.6%) of 3224 subjects had heartburn and/or regurgitation at least once a week. On univariate analysis, older age (OR 1.012; 95% CI 1.003–1.021), consumption of non-vegetarian and fried foods, aerated drinks, tea/coffee were associated with GERD. Frequency of smoking was similar among subjects with or without GERD. Body mass index (BMI) was similar in subjects with and without GERD. On multivariate analysis, consumption of non-vegetarian food was independently associated with GERD symptoms. Overlap with symptoms of irritable bowel syndrome was not uncommon; 21% reported difficulty in passage of stool and 9% had mucus in stools. About 25% of patients had consulted a doctor previously for their gastrointestinal symptoms.

Conclusion

7.6% of Indian subjects have significant GERD symptoms. Consumption of non-vegetarian foods was an independent predictor of GERD. BMI was comparable among subjects with or without GERD.  相似文献   
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Radiologically guided balloon catheters were used to dilate 94 gastrointestinal strictures in 92 patients over a 6-year period. Fifty strictures were esophageal and 44 nonesophageal (22 gastroenterostomies, 11 antral-pyloric strictures, four colorectal strictures, four enteroenterostomies, and three miscellaneous strictures). Factors influencing the success of stricture intubation included patient age, stricture location (esophageal vs. nonesophageal and proximal vs. distal esophageal), and association with a surgical anastomosis. Malignancy was associated with greater postdilation irregularity and a smaller increase in stricture diameter, as measured radiographically. Procedural failures occurred in 8% of cases (2% of esophageal and 30% of nonesophageal lesions). Two small, asymptomatic mucosal tears were seen after dilation (one esophageal and one colonic); no other procedural complications occurred. Following successful dilation, 16 patients (17%; six with esophageal and ten with non-esophageal strictures) had recurrence of symptoms during short-term (30-day) follow-up.  相似文献   
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M. Thomas  M. Behari  GK Ahuja 《Headache》1991,31(9):613-615
Flunarizine, a calcium channel blocker is considered useful in migraine prophylaxis. We report the first Indian trial with this drug. Fifteen patients with migraine were studied in a 6 months double-blind, placebo-controlled crossover trial. Flunarizine was superior to placebo in reducing the severity and duration of the individual attacks though there was no statistically significant effect on frequency of migraine attacks. The side effects most frequently caused by flunarizine were weight gain and daytime sleepiness.  相似文献   
20.
Carrier-directed anti-hapten responses by b-cell subsets   总被引:2,自引:2,他引:2       下载免费PDF全文
The capacity of the trinitrophenyl (TNP) haptenic group, coupled to a series of chemically dissimilar carriers, to cross-stimulate putative T- dependent and T-independent murine B-cell subpepulations was determined by using an in vitro limiting dilution technique to generate primary IgM responses. It was found that TNP-Ficoll and TNP-dextran, two T- independent antigens with little or no polyclonal mitogenicity, stimulate the same population of anti-TNP precursors, which is distinct from the precursor population activated by TNP-bacterial lipopolysaccharide (LPS), a T-independent polyclonal mitogen, or TNP-horse erythrocytes (HRBC), a T-dependent antigen. On the other hand, TNP-LPS and TNP-HRBC activate the same precursor population, indicating that LPS can substitute for the T- cell signal in T-dependent B-cell responses, whereas nonmitogenic T- independent antigens cannot. However, the cumulative evidence from this and other laboratories strongly indicates that LPS and T-dependent antigens activate B cells by different mechanisms. Of particular interest, LPS is incapable of activating B cells responsive to weakly- or nonmitogenic T-independent antigens. Based on clonal burst size, T-dependent antigens are capable of inducing greater antigen-specific B-cell proliferation than T-independent antigens. However, TNP conjugates of Ficoll and dextran, which are relatively poor inducers of polyclonal B-cell activation, induced larger anti-TNP clones than did TNP-LPS, a strong polyclonal mitogen. The findings reinforce the evidence favoring existence of multiple B- cell subpopulations with distinctive activation pathways. They also strengthen the proposition that a given B-cell subset can be activated by more than one mechanism.  相似文献   
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