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991.
AIM: To determine the prevalence of hepatitis B in Nahavand and evaluate the HBsAg positive prevalence in families with a member who was confirmed to have HBV infection. METHODS: This study was performed in two phases. In the first phase, 1 824 subjects in Nahavand city were selected. The interviewers visited the houses of chosen families to fill the questionnaire and take the blood samples. All subjects signed an informed consent before interviews and blood sampling. The samples were evaluated for HBV virologic markers. In the second phase, 115 HBsAg-positive cases were enrolled and evaluated for HBV virologic markers. RESULTS: The prevalence of positive HBsAg in Nahavand was 2.3%. The most frequent relatives of index cases were sons and daughters (32.2% and 23.5% respectively). Twelve (11%) of all family members were HBsAg positive. Fifty (56.2%) were isolated HBsAb positive and only one person (2,5%) was isolated HBcAb positive. The higher rates of HBsAg marker were detected in the brothers (1-25%) and fathers (1-12.5%). The infection rate in husbands and wives of index cases was 10%. Only two (16.7%) of all HBsAg-positive participants reported previous HBV vaccination. CONCLUSION: The prevalence of intra-familial HBV infection is lower in Nahavand of Iran compared to other studies. More attention should be paid to HBV vaccination and risk-lowering activities.  相似文献   
992.
993.
Hydatid disease is a parasitic infection that is remains endemic in many countries, particularly the Middle East and Central Asia. Mediastinal hydatidosis is very rare (less than 0.1% of all hydatid disease cases) that have been only anecdotally in the literature. To the best of our knowledge only one case of multiple mediastineal hydatid cysts has been reported previously. We report the second cases of multiple mediastineal hydatid cysts and recommend that it can be considered in the differential diagnosis of multiple cystic mediastineal masses in endemic countries.  相似文献   
994.

Background:

Most thalassemic patients with chronic hepatitis C virus (HCV) infection do not respond to therapy with pegylated interferon (Peg-IFN) plus ribavirin (RBV) due to hepatic siderosis and RBV dose reduction caused by RBV-induced anemia.

Objectives:

In the present study, we recruited HCV genotype 1-infected thalassemic patients who had relapsed after a 48-week treatment with Peg-IFN plus RBV in order to evaluate the efficacy of a 72-week regimen of Peg-IFN plus RBV.

Patients and Methods:

In this retrospective study, 23 thalassemic patients with HCV genotype 1 infection who had prior relapse after treatment with Peg-IFN and RBV for 48 weeks were consecutively enrolled in this study for evaluation of the efficacy of a 72-week treatment regimen.

Results:

For the 21 included cases, mean age was 29.7 years; 81% were men and 28.6% had cirrhosis. At the end of the treatment, nine (42.9%) patients had an undetectable level of HCV RNA in their sera. However, six months after treatment completion four of these patients relapsed and a sustained virological response (SVR) was found in five (23.8%) patients. Undetectable HCV RNA level at week 4 (P = 0.03) and undetectable HCV RNA level at week 12 (P < 0.01) were found to be predictors of SVR. There was an average 47.9% increase in blood transfusion during therapy and treatment was discontinued for 12 (57.1%) patients prematurely.

Conclusions:

The present study suggests that thalassemic patients with chronic hepatitis C genotype 1 infection who did not achieve SVR after a course of therapy with Peg-IFN and RBV may benefit from being retreated with a 72-week regimen.  相似文献   
995.

Background

Cirrhosis, associated with a host of hemodynamic abnormalities, could affect the gastrointestinal (GI) tract motility. On the other hand, the nonadrenergic noncholinergic (NANC) neurotransmission has been shown to play a pivotal role in GI tract motility and has been linked with release of nitric oxide (NO) on electrical stimulation. In this study, we investigated the effect of biliary cirrhosis on the neurogenic relaxation of rat gastric fundus and anococcygeus muscle and also the possible role of nitric oxide system in this manner.

Methods

Isolated gastric fundus and anococcygeus strips of sham-operated and biliary cirrhotic (4 weeks after bile duct ligation) rats were mounted under tension in a standard organ bath. Electrical stimulation was applied to obtain NANC-mediated relaxations in precontracted gastric fundus and anococcygeus muscle. The neurogenic relaxations were examined in the presence of different doses of NO synthase inhibitor, N w-Nitro-l-Arginine Methyl Ester (l-NAME). The concentration-dependent relaxant responses to the NO donor sodium nitroprusside were also evaluated.

Results

The neurogenic relaxation of both gastric fundus and anococcygeus muscle was significantly (P < 0.001) increased in cirrhotic animals. l-NAME (0.03–1,000 µM) inhibited relaxations in both groups in a dose-dependent manner (P < 0.001), but cirrhotic groups were more resistant to the inhibitory effects of l-NAME (P < 0.01). Sodium nitroprusside-mediated relaxations were similar in two groups.

Conclusions

This study for the first time demonstrated that cirrhosis increases the NO-mediated neurogenic relaxation of both rat gastric fundus and anococcygeus muscle, suggesting a crucial role for the neurogenic NO in the pathophysiology of disturbed GI motility in cirrhosis.  相似文献   
996.

Objective

To determine whether a 3-month contraceptive vaginal ring (CVR) delivering ulipristal acetate (UPA) can inhibit ovulation in 90% of cycles.

Study Design

This was a randomized dose-finding parallel group clinical trial. Fifty-five healthy women with normal ovulation at baseline were randomized to receive a low-dose (1500 μg/day) or a high-dose (2500 μg/day) UPA-CVR for two consecutive 12-week treatment periods, followed by a recovery cycle. A subgroup of women received levonorgestrel (LNG) 1.5 mg orally twice (at the end of both 12-week ring periods) or once (at the end of the 24-week treatment). The primary outcome was ovulation suppression assessed by transvaginal ultrasound and hormone levels. Secondary outcomes included endometrial safety and bleeding patterns.

Results

All subjects showed normal ovulation at baseline and recovery. Ovulation suppression was seen in 81.8% (95% CI: 73.3%, 88.5%) and 86.1% (95% CI: 78.1%, 92%) of treatment cycles with low and high-dose, respectively. Benign progesterone receptor modulator associated endometrial changes (PAEC) were seen during treatment; 78.8% at week 24, but resolved at recovery cycle. A few cases of heavy bleeding occurred near the end of the 24-week treatment, but a single dose of LNG every 12 weeks reduced the increase in endometrial thickness during the second treatment period and prevented excessive bleeding.

Conclusion

The 3-month UPA-CVR may become an effective long-acting, user-controlled estrogen-free contraceptive. The greatest suppression of ovulation was seen with the 2500-μg/day ring.

Implications

The 3-month CVR delivering UPA 2500 μg/day can become an effective user-controlled estrogen-free contraceptive method. Benign PAEC during treatment returns to normal after discontinuation. The prevention of occasional excessive withdrawal bleeding, either by a progestin or by using higher UPA levels to increase follicle suppression may permit prolonged treatment.  相似文献   
997.
The prevalence of gastric ulcers is high in cholestatic patients, but the exact mechanism of this increased frequency remains uncertain. It has been shown that pioglitazone accelerates the healing of pre‐existing gastric ulcers. The present study was designed to investigate the effect of pioglitazone, on the gastric mucosal lesions in cholestatic rats. Cholestasis was induced by surgical ligation of common bile duct and sham‐operated rats served as control. Different groups of sham and cholestatic animals received solvent or pioglitazone (5, 15, 30 mg/kg) for 7 days. On the day eight rats were killed after oral ethanol administration and the area of gastric lesions was measured. The serums of rats were also collected to determine serum levels of tumour necrosis factor alpha (TNF‐α), IL‐1β and bilirubin. The ethanol‐induced gastric mucosal damage was significantly more severe in cholestatic rats than sham‐operated ones. Pretreatment with pioglitazone dose‐dependently attenuated gastric lesions induced by ethanol in both sham and cholestatic rats, but this effect was more prominent in cholestatic ones. The effect of pioglitazone was associated with a significant fall in serum levels of TNF‐α in cholestatic rats. L‐NAME, a non‐selective nitric oxide synthase (NOS) inhibitor, and decreased pioglitazone‐induced gastroprotective effect in cholestatic rats, while aminoguanidine, a selective inducible NOS inhibitor, potentiated pioglitazone‐induced gastroprotective effect in the cholestatic rats. Chronic treatment with pioglitazone exerts an enhanced gastroprotective effect on the stomach ulcers of cholestatic rats compared to sham rats probably due to constitutive NOS induction and/or inducible NOS inhibition and attenuating release of TNF‐α.  相似文献   
998.

Background

Preschool-aged children are the highest consumers of antibiotics, but consult mainly for viral infections. Little is known about how day care, which is common in this age group, influences primary care consulting and treatment-seeking behaviours.

Aim

To investigate daycare providers’ approaches to excluding and/or readmitting children with infections, and the consequences for parents’ consulting and antibiotic-seeking behaviours.

Design and setting

Cross-sectional survey, document analysis, and qualitative interviews of daycare providers and parents in South East Wales, UK.

Method

A total of 328 daycare providers were asked to complete a survey about infection exclusion practices and to provide a copy of their sickness exclusion policy. Next, 52 semi-structured interviews were conducted with purposively selected questionnaire responders and parents using their services. Questionnaire responses underwent bivariate analysis, policies underwent document analysis, and interviews were thematically analysed using constant comparison methods.

Results

In total 217 out of 328 (66%) daycare providers responded; 82 out of 199 (41%) reported advising parents that their child may need antibiotics and 199 out of 214 (93%) reported advising general practice consultations. Interviews confirmed that such advice was routine, and beliefs about antibiotic indications often went against clinical guidelines: 24% (n = 136) of sickness exclusion policies mentioning infections made at least one non-evidence-based indication for ‘treatment’ or antibiotics. Parent interviews revealed that negotiating daycare requirements lowered thresholds for consulting and encouraged antibiotic seeking.

Conclusion

Daycare providers encourage parents to consult general practice and seek antibiotics through non-evidence-based policies and practices. Parents’ perceptions of daycare providers’ requirements override their own beliefs of when it is appropriate to consult and seek treatment.  相似文献   
999.
An ascent to altitude has been shown to result in more central apneas and a shift towards lighter sleep in healthy individuals. This study employs spectral analysis to investigate the impact of respiratory disturbances (central/obstructive apnea and hypopnea or periodic breathing) at moderate altitude on the sleep electroencephalogram (EEG) and to compare EEG changes resulting from respiratory disturbances and arousals. Data were collected from 51 healthy male subjects who spent 1 night at moderate altitude (2590 m). Power density spectra of Stage 2 sleep were calculated in a subset (20) of these participants with sufficient artefact‐free data for (a) epochs with respiratory events without an accompanying arousal, (b) epochs containing an arousal and (c) epochs of undisturbed Stage 2 sleep containing neither arousal nor respiratory events. Both arousals and respiratory disturbances resulted in reduced power in the delta, theta and spindle frequency range and increased beta power compared to undisturbed sleep. The similarity of the EEG changes resulting from altitude‐induced respiratory disturbances and arousals indicates that central apneas are associated with micro‐arousals, not apparent by visual inspection of the EEG. Our findings may have implications for sleep in patients and mountain tourists with central apneas and suggest that respiratory disturbances not accompanied by an arousal may, none the less, impact sleep quality and impair recuperative processes associated with sleep more than previously believed.  相似文献   
1000.

OBJECTIVE

To assess findings of mammography of and interventions resulting from breast cancer screening in women aged 40-49 years with no increased risk (typical risk) of breast cancer.

METHODS

This cross-sectional study evaluated women aged 40-49 years who underwent mammography screening in a mastology reference center in Recife, PE, Northeastern Brazil, between January 2010 and October 2011. Women with breast-related complaints, positive findings in the physical examination, or high risk of breast cancer were excluded.

RESULTS

The 1,000 mammograms performed were classified into the following Breast Imaging-Reporting and Data System (BI-RADS) categories BI-RADS 0, 232; BI-RADS 1, 294; BI-RADS 2, 294; BI-RADS 3, 16; BI-RADS 4A, 2; BI-RADS 5, 1. There was one case of grade II invasive ductal carcinoma and various interventions, including 469 ultrasound scans, 53 referrals to mastologists, 11 cytological examinations, and 8 biopsies.

CONCLUSIONS

Mammography screening in women aged 40-49 years with typical risk of breast cancer led to the performance of other interventions. However, it also resulted in increased costs without demonstrable efficacy in decreasing mortality.  相似文献   
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