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1.
Insemination with donor spermatozoa is an integral part of infertility treatment. For the last 3 years in our unit, intrauterine insemination with donor spermatozoa (IUID) has been used in preference to vaginal insemination. In this retrospective study, patients were offered an initial course of five single intrauterine inseminations with cryopreserved donor spermatozoa and treatment was then reviewed. A total of 389 patients received 1465 inseminations. In all, 1119 cycles were monitored using luteinizing hormone serum analyses and 346 cycles using the urine home test kits. The clinical pregnancy rate per insemination for the cycles monitored by the serum assay was 18.0% (202/1119) compared with the urine cycles (13.7%, 46/346) (P <05). The pregnancy loss rate was not significantly different (14.4%, 29/202 and 21.7%, 10/46) (serum and urine cycles respectively). The viable clinical pregnancy rate was significantly higher (P <03) for the serum cycles than for the cycles using the urinary monitoring (15.5%, 173/1119 and 10.4%, 36/346 respectively). The cycles monitored by serum assay had a significantly higher cumulative viable clinical pregnancy rate (P <0001) of 70.2% after nine inseminations compared with the urine monitored cycles of 54.8%. The majority of patients opted for the serum cycles, with a minority self-selecting the urine cycles mainly for travelling convenience. The explanation for the significant differences between the viable clinical pregnancy rates per insemination and the cumulative viable clinical pregnancy rates may be due to the sensitivity of the urine home test kit or the patients' interpretation of the result.   相似文献   
2.
A functional fabric immobilized by the microcapsules of C. aurantifolia lime essential oil (LO) was prepared and characterized. A varied amount of CaCl2 crosslinker was optimized to coacervate LO using alginate–gelatin biopolymers and Tween 80 emulsifier. A further evaluation of the immobilized LO microcapsules for the antibacterial effect against both Gram-positive and Gram-negative bacteria was conducted. The optimized alginate/gelatin-based microcapsules were effectively crosslinked by 15% CaCl2 with an yield, oil content (OC), and encapsulation efficiency (EE) of 39.91 ± 3.10%, 78.33 ± 7.53%, and 90.27 ± 5.84%, respectively. A spherical shape of LO microcapsules was homogeneously found with an average particle size of 1.394 μm. A first-order kinetics mechanism for the release of LO out of the microcapsules was modeled by Avrami''s kinetic equation (k = 1.60 ± 3.68 × 10−5 s−1). The LO microcapsules demonstrated good thermal stability up to 100 °C and maintained 51.07% OC and 43.56% EE at ambient temperature for three weeks. Using a pad dry method and citric acid binder, LO microcapsules were successfully immobilized on a cloth with a % add on 30.60 ± 1.80%. The LO microcapsules and the immobilized one exhibited a moderate ZoI of bacterial growth for Gram-positive S. aureus and S. epidermidis as well as Gram-negative E. coli and K. pneumonia. Further washing test toward the functional fabric showed that the LO microcapsules incorporated into the fabric were resistant to five cycles of normal washing with a mass reduction of 22.01 ± 1.69%.

A functional fabric immobilized by the microcapsules of C. aurantifolia lime essential oil (LO) was prepared and characterized.  相似文献   
3.
The aim of this paper is to characterise the fatigue reliability for various random strain loads under extreme value distribution while considering the cycle sequence effect condition in fatigue life prediction. The established strain–life models, i.e., Morrow and Smith–Watson–Topper, considered a mean stress effect and strain amplitude; nevertheless, it excluded the load sequence effect, which involves the fatigue crack closure that is subjected to overload or underload. A FESEM-EDX analysis is conducted to characterise the failure features that occurred on the leaf spring. A finite element is simulated to determine the critical region in order to obtain the strain load behaviour. In addition, the strain signal is captured experimentally at 500 Hz for 100 s under operating conditions for three different road loads based on the critical location obtained from the finite element analysis. The fatigue life correlation shows that the Pearson correlation coefficients are greater than 0.9, which indicates the effective strain damage model is linearly correlated with the strain–life models. The fatigue life data are modelled using extreme value distribution by considering the random strain loads as extreme data. The reliability rate for the fatigue life is reported to be more than 0.59 within the hazard rate range of 9.6 × 10−8 to 1.2 × 10−7 based on the mean cycle to the failure point. Hence, the effective strain damage model is proposed for a fatigue reliability assessment under extreme conditions with higher reliability and provides fatigue life prediction when subjected to cycle sequence effects.  相似文献   
4.
Cancer is the second leading cause of death all around the world. The natural compounds derived from the endophytic flora of fungi are possible solutions to cancer treatment because they are safe for health, cost-effective, biocompatible and have fewer toxicity issues. The active ingredients in endophytic fungi that are responsible for anti-cancer activities are alkaloids, terpenoids, glycosides, saponin, peptides, steroids, phenols, quinones, and flavonoids. This review highlights the anti-cancer activities of entophytic fungus against human papillary thyroid carcinoma (IHH4), human pancreatic (PANC-1), ovarian (OVCAR-3), hepatic (HepG2), lung (A-549), human lymphoma (U937), human skin carcinoma (A431), breast (MCF-7), and Kaposi’s sarcoma. The emerging evidence suggested that bioactive compounds isolated from endophytic fungi showed their anti-cancer activities by revealing the disturbance of the microtubule network caused by increased levels of Bax and Bcl-2 proteins that triggers cell cycle arrest at the G2-M phase, by inhibiting the DNA replication via binding with topoisomerase II, by regulating the activity of extracellular signal-regulated kinase and NF-kB, by evaluating the levels of p21, p27, and cyclins B/D1/E that led to cell death by apoptosis and cell cycle arrest. This review will assist readers in better comprehending bioactive chemicals and the beneficial interaction between the fungal endophytes and medicinal plants.  相似文献   
5.
The intestinal permeability of mitragynine was investigated in situ using a single pass intestinal perfusion (SPIP) absorption model, in small intestine of rat using mitragynine in the absence/presence of the permeability markers, P-gp and/or CYP3A4 inhibitors. Mitragynine demonstrated high intestinal permeability (Peff of 1.11 × 10?4 cm/s) that is in the range of highly permeable drugs such as propranolol (Peff of 1.27 × 10?4 cm/s) indicating that it readily crosses the intestine. The addition of azithromycin (P-glycoprotein inhibitor) and ciprofloxacin (CYP3A4 inhibitor) or combination of both has no effect on intestinal permeability of mitragynine across the rat small intestine.  相似文献   
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A total of 90 cases of pneumococcal infections were identified at a major referral hospital in Kuala Lumpur, Malaysia during a study period of four years. Pneumonia was the most common clinical presentation (41 cases) followed by meningitis (19 cases). Of 48 patients who were followed-up during the microbiology consultation round, 11 died, 9 were children below two years old. Capsular typing was carried out on 57 strains of Streptococcus pneumoniae isolated from blood and body fluids of 43 children and 14 adults. 38 strains isolated from pharyngeal specimens were also typed. Types 6A (11 strains), 6B (7 strains), 14 (8 strains) and 19A (8 strains) predominated in children. The strains from older patients comprised 3 isolates from cerebrospinal fluid (types 18B, 6B and 14), five from blood (4 strains, type 1 and 1 strain, type 4) and six from pus (1 strain, type 14, 3 strains type 23F and 2 strains type 34). The isolates from pharyngeal specimens belonged to capsular type similar to those implicated in infections. 90% of the types reported in this study are included in the 23 valent pneumococcal vaccines. Minimum inhibitory concentrations of penicillin, cefuroxime, chloramphenicol and rifampicin were determined for selected strains. 4.1% of isolates were resistant to penicillin (3/74), 4.5% to cefuroxime (2/44), 6.5% to chloramphenicol (3/46) and 14.6% to rifampicin (6/41).  相似文献   
9.
In this study, a composite material, manganese oxide/reduced titania nanotubes (Mn2O3/R-TNTs), was synthesized through incorporation of Mn2O3 onto R-TNTs via the reverse pulse electrodeposition technique. The influence of pulse reverse duty cycles on the morphological, structural and electrochemical performance of the surface was studied by varying the applied duty cycle from 10% to 90% for 5 min total on-time at an alternate potential of −0.90 V (Eon) and 0.00 V (Eoff). FESEM analysis revealed the uniform deposition of Mn2O3 on the circumference of the nanotubes. The amount of Mn2O3 loaded onto the R-TNTs increased as a higher duty cycle was applied. Cyclic voltammetry and galvanostatic charge–discharge tests were employed to elucidate the electrochemical properties of all the synthesized samples in 1 M KCl. The specific capacitance per unit area was greatly enhanced upon the incorporation of Mn2O3 onto R-TNTs, but showed a decrease as a high duty cycle was applied. This proved that low amounts of Mn2O3 loading enhanced the facilitation of the active ions for charge storage purposes. The optimized sample, Mn2O3/R-TNTs synthesized at 10% duty cycle, exhibited high specific capacitance of 18.32 mF cm−2 at a current density of 0.1 mA cm−2 obtained from constant current charge–discharge measurements. This revealed that the specific capacitance possessed by Mn2O3/R-TNTs synthesized at 10% duty cycle was 6 times higher than bare R-TNTs.

Mn2O3 was coated onto reduced titania nanotubes by reverse pulse electrodeposition, showing smooth and homogenous deposits without covering the opening of the nanotubes.  相似文献   
10.
The use of fibers in cementitious composites yields numerous benefits due to their fiber-bridging capabilities in resisting cracks. Therefore, this study aimed to improve the shear-resisting capabilities of conventional concrete through the hybridization of multiple synthetic fibers, specifically on reinforced concrete structures in seismic-prone regions. For this study, 16 hybrid fiber-reinforced concretes (HyFRC) were developed from the different combinations of Ferro macro-synthetic fibers with the Ultra-Net, Super-Net, Econo-Net, and Nylo-Mono microfibers. These hybrids were tested under direct shear, resulting in improved shear strength of controlled specimens by Ferro-Ultra (32%), Ferro-Super (24%), Ferro-Econo (44%), and Ferro-Nylo (24%). Shear energy was further assessed to comprehend the effectiveness of the fiber interactions according to the mechanical properties, dosage, bonding power, manufactured material, and form of fibers. Conclusively, all fiber combinations used in this study produced positive synergistic effects under direct shear at large crack deformations.  相似文献   
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