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21.
Herein, well dispersed Ag–Cu NPs supported on modified graphene have been synthesized via a facile and rapid approach using sodium borohydride as a reducing agent under ambient conditions. Dicyandiamide is selected as an effective nitrogen source with TiO2 as an inorganic material to form two kinds of supports, labelled as TiO2–NGO and NTiO2–GO. Initially, the surface area analysis of these two support materials was carried out which indicated that N-doping of GO followed by anchoring with TiO2 has produced support material of larger surface area. Using both types of supports, ten nano-metal catalysts based on Ag and Cu were synthesized. Benefiting from the bimetallic synergistic effect and larger specific surface area of TiO2–NGO, Cu@Ag–TiO2–NGO is found to be a highly active and reusable catalyst out of other synthesized catalysts. It exhibits excellent catalytic activity for oxidation of alcohols and hydrocarbons as well as Chan–Lam coupling reactions. The nanocatalyst is intensively characterized by BET, SEM, HR-TEM, ICP-AES, EDX, CHN, FT-IR, TGA, XRD and XPS.

Cu@Ag–TiO2–NGO prepared from modified graphene by simple methodology exhibits enhanced catalytic activity towards oxidation and Chan–Lam coupling due to the synergistic effect between Ag and Cu NPs.  相似文献   
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Introduction and hypothesis

To determine if the classification of obstetric anal sphincter injuries (OASIs) affected clinical and functional outcome and to assess the need for follow-up of 3a tears in secondary care

Methods

Prospective data collection in 255 patients who sustained OASIs during repair with follow-up in a specialist clinic after 6 months.

Results

One hundred and thirty-two patients (51.7 %) sustained 3a tears, 81 (31.7 %) 3b tears, 27 (10.6 %) 3c tears and 15 (5.8 %) had 4th degree tears. Twenty-three patients (9 %) reported symptoms at 6-month follow-up. Eight patients reported anal incontinence of liquid or solid stool. Among patients who sustained 3a tears, 8 patients were symptomatic: 7 had urgency and 1 had flatus incontinence. None of the patients who sustained 3a tears reported incontinence of solid/liquid stool. There appears to be no correlation with scan findings and symptoms at follow up. Most patients are asymptomatic. Urgency of faeces is the commonest symptom.

Conclusions

The vast majority of patients are asymptomatic. The necessity of seeing all these patients in secondary care for follow-up needs to be questioned. With effective primary care follow-up, there may be a place to follow up patients with 3a tears in the community during the routine 6-week postnatal check and refer the symptomatic patients to the hospital for further review.  相似文献   
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Objective: This study aims to evaluate the change in serum anti-Mullerian hormone (AMH) levels in patients with morbid obesity undergoing bariatric surgery for weight loss.

Material and methods: In this prospective observational study, 75 patients of reproductive age (20–35 years) undergoing bariatric surgery for morbid obesity were followed up after six months to determine the changes in weight, Body Mass Index (BMI), menstrual pattern and serum AMH. The results were further studied on basis of pre operative classification of patients in polycystic ovary syndrome (PCOS) and non-PCOS group.

Result: The serum AMH levels were statistically higher in patients of PCOS group pre operatively and at the end of six months in comparison to non-PCOS patients. The AMH values reduced post operatively in both groups significantly so much in the values though not significant statistically. Non-PCOS patients had lower AMH values pre operatively and showed a trend towards reducing ovarian reserve after six months. The overall change in AMH values in both groups was statistically significant as was the normalization of menstrual irregularity.

Conclusion: Morbidly obese patients with PCOS appear to benefit from bariatric surgery both in terms of regularization of menstrual function and normalization of serum AMH values.  相似文献   

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A 40-year-old woman presents to the emergency department after a motor vehicle accident, and a CT scan revealed no injuries but incidentally notes three non-obstructing stones in the left kidney of 3, 4, and 5 mm in size. She is completely asymptomatic and has no history of urolithiasis.  相似文献   
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Imam  Mohamed  Shehata  Mohamed  Morsi  Mahmoud  Shawqi  Muhammad  Elsehili  Ahmed  Trikha  Paul  Ernstbrunner  Lukas  Unnithan  Ashwin  Khaleel  Arshad  Monga  Puneet  Narvani  Ali  Sallam  Asser 《HSS journal》2020,16(3):222-232
HSS Journal ® - Hip hemiarthroplasty is a well-established treatment of displaced femoral neck fracture, although debate exists over whether cemented or uncemented fixation is superior....  相似文献   
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