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1.
Neonatal respiratory distress syndrome (RDS) is one of the biggest problems in modern obstetrics. The incidence of RDS is 1%-2%. RDS is a condition of insufficient surfactant production. Surfactant is a complex molecule which is responsible for maturation of fetal lungs. The most important factor for insufficient surfactant production and pulmonary immaturity is shortening of gestation, i.e. preterm delivery. Antenatal corticosteroids for maturation of fetal lungs are in use for over thirty years. Corticosteroids decrease the incidence and intensity of RDS, the severity of intracerebral hemorrhage, and overall neonatal morbidity and mortality. The mechanism of corticosteroid action is probably induction of fetal pulmonary enzyme complex that is responsible for adequate surfactant production and regulation of pulmonary interstitial fluids. In this literature review, we analyze long- and short-term benefits and risks of single and multiple antenatal corticosteroid administration.  相似文献   
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Introduction: A clinically normal‐appearing nipple in patients with breast cancer may contain unsuspected neoplastic cells. Preservation of a nipple containing occult malignancy could potentially increase local recurrence rates and affect disease‐free survival. Consequently, patients considered for breast conservation operations with nipple preservation must be carefully selected. Methods: Information available on 382 patients diagnosed and treated with breast cancer at the Clinical Center Nis from 2000 to 2003 were retrospectively reviewed. Multivariate hazard analyses was used to assess the association between potential risk factors of cancerous nipple involvement. Results: The frequency of nipple involvement was 12.04%. Nearly half of the patients had disease stage III and IV. Most patients, 29 (63.04%), had a tumor to nipple distance of less then 2 cm. Twenty‐five patients (54.34%) had more then four positive axillary nodes. A central/overlap tumor location was present in 28 (60.87%) patients. Cox multivariate analysis of prognostic factors showed that Stage III (RH 4.79 (1.50–14.68, 1.50–14.72); P= 0.008), central/overlap tumor location (RH 3.28 (0.90–11.20); P= 0.078) and nuclear grade III or greater (RH 2.26 (0.79 to 6.65); P= 0.065) had a statistically significant effect on malign nipple involvement. Conclusions: The multivariable model used in this study showed a significant association between stage, centrally located tumors and nuclear grade III or greater in predicting the risk of cancerous nipple involvement. Preoperative magnetic resonance imaging or computed tomography scan examinations are recommended for treatment planning of breast cancer, in particular nipple preserving surgery in patients with central/overlap tumor localization and with a tumor to nipple distance of less than 2 cm.  相似文献   
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OBJECTIVE: This study was performed in order to compare the performance of classical two dimensional (2D) and three dimensional (3D) ultrasound, both with power Doppler technology, in the visualization of the placental vascular network during ongoing pregnancy. METHODS: 15 pregnant volunteers in the third trimester of pregnancy were examined by 2D and 3D power Doppler ultrasound. The aim of the study was to follow the branching of the main stem vessel as far as possible distally in the placenta. In addition, we assessed the visualization rate of terminal parts of uteroplacental circulation, radial and spiral arteries. RESULTS: There was no difference in the visualization of primary placental stem vessels by 2D and 3D power Doppler. However, 3D power Doppler performs better distally, with statistically significant differences at the level of secondary stem (p = 0.03), and even more prominent differences at the level of tertiary stem vessels (p = 0.0008). There was no difference in the visualization rate of radial and spiral arteries (p > 0.05). CONCLUSION: We found 3D superior to 2D ultrasound with power Doppler technology in the determination of the distal vascular branches of the fetal placental blood vessels.  相似文献   
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Aims

The objective of the present substudy was to examine whether aspirin poor/high responsiveness (APR/AHR) is associated with increased rates of major adverse cardiovascular events (MACE) and serious bleeding after primary percutaneous coronary intervention (PPCI).

Methods

We analyzed 961 consecutive ST-elevation acute myocardial infarction patients who underwent PPCI between February 2008 and June 2011. Multiplate analyser (Dynabite, Munich, Germany) was used for the assessment of platelet reactivity. APR/AHR were defined as the upper/lower quintiles of ASPI values, determined 24 h after aspirin loading. APR patients were tailored using 300 mg maintenance dose for 30 days. The co-primary end points at 30 days were: MACE (death, non-fatal infarction, ischemia-driven target vessel revascularization and ischemic stroke) and serious bleeding according to the BARC classification.

Results

One hundred and 90 patients were classified as APR, and 193 patients as AHR. At admission, compared with aspirin sensitive patients (ASP), patients with APR had more frequently diabetes, anterior infarction and heart failure, while AHR patients had reduced values of creatine kinase, leukocytes, heart rate and systolic blood pressure. Compared with ASP, the rates of 30-day primary end points did not differ neither in APR group including tailored patients (MACE, adjusted OR 1.02, 95%CI 0.47-2.17; serious bleeding, adjusted OR 1.92, 95%CI 0.79-4.63), nor in patients with AHR (MACE, adjusted OR 1.58, 95%CI 0.71-5.51; serious bleeding, adjusted OR 0.69, 95%CI 0.22-2.12).

Conclusions

The majority of APR patients were suitable for tailoring. Neither APR including tailored patients nor AHR were associated with adverse 30-day efficacy or safety clinical outcomes.
  相似文献   
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Purpose

A recurrent lumbar disc herniation (RLDH) is the most prevalent cause for new radicular pain after surgery for disc herniation-induced sciatica. Reported risk factors include age, gender and smoking, while its surgical treatment is associated to a higher rate of complications and costs. The purpose of this study is to identify factors that increase the risk of requiring surgical treatment for a first RLDH in workers’ compensation patients.

Methods

Nested case–control: 109 patients operated for an RLDH (cases) between June 1st 1994 and May 31st 2011 (minimum follow-up 1 year) and 109 randomly selected patients operated for a first disc herniation with no recurrence during the study period (controls). Age, gender, smoking status, type of work and MRI characteristics of the index herniation were statistically evaluated as potential risk factors.

Results

Patient’s age of less than 35 years (p = 0.001) and a subligamentous herniation (p < 0.05) at the time of the index surgery were identified as risk factors for requiring surgical treatment of a first RLDH. No statistical differences were observed between both groups regarding the other evaluated variables.

Conclusion

A subligamentous disc herniation and patient’s age inferior to 35 years at the time of the first surgery are risk factors for requiring surgical treatment of a first RLDH among workers’ compensation patients.
  相似文献   
10.
Anxiety disorders are the most frequent mental disorders and are more prevalent in the female population. Up to date, an involvement of guanylate cyclase A and B in anxiety‐like behavior has been suggested. In this study, we showed an expression of guanylate cyclase C (GC‐C) in the amygdala which is regulated by feeding. Therefore, we further investigated sex differences of GC‐C effects on anxiety levels with special attention to female estrous cycle and feeding. The effects of estrous cycle and feeding were investigated by several behavior tests: elevated plus maze, home cage escape and novelty‐induced hypophagy. Possible changes in GC‐C expression in amygdala and hypothalamus during estrous cycle were established by qPCR. When GC‐C is activated (after a meal), the sex difference in all behavior tests used was abolished. As the expression of mRNA for GC‐C in the amygdala increases 2 hr after a meal only in female animals, the anxiety levels change after a meal again only in female animals. When the anxiety levels are investigated, it is very important to pay attention not only to estrous cycle in female animals but also when animals were fed compared to the time point of the experiments. Concluding from our results, the sex differences in the incidence of anxiety disorders in humans could be GC‐C dependent.  相似文献   
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