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BACKGROUND: Microfluidic technology has been utilized in numerous biological applications specifically for miniaturization and simplification of laboratory techniques. We sought to apply microfluidic technology to murine IVF. METHODS: Microfluidic devices measuring 500 microm wide, 180 microm deep, and 2.25 cm in length were designed and fabricated using poly(dimethylsiloxane) (PDMS). Controls were standard centre-well culture dishes with 500 microl of media, half of which also contained PDMS as a material control. Denuded mouse oocytes were placed into microchannels or centre-well dish controls in groups of 10, then co-incubated overnight with epididymal mouse sperm at various concentrations. Fertilization was assessed and Fisher's exact test was used for statistical analysis (P < 0.05 significant). RESULTS: Fertilization rates between the two control groups (42%, no PDMS; 41%, with PDMS; not significant) were similar. Fertilization rates for denuded oocytes at standard mouse insemination sperm concentration (1 degrees 10(6) sperm/ml) was poorer in microchannels (12%) than controls (43%; P < 0.001). As insemination concentrations decreased, fertilization rates improved in microchannels with a plateau between 8 degrees 10(4) and 2 degrees 10(4) sperm/ml (4000-1000 total sperm). At these concentrations, combined fertilization rate for denuded oocytes was significantly higher in microchannels than centre-well dishes (27 versus 10%, respectively; P < 0.001), and was not significantly different from corresponding controls with a sperm concentration of 1 degrees 10(6) (37%; P = 0.06). CONCLUSIONS: Murine IVF can be conducted successfully within microfluidic channels. Lower total numbers and concentrations of sperm are required. Microfluidic devices may ultimately be useful in clinical IVF.  相似文献   
103.
Sir, We read with interest the article on cerebral venous sinus thrombosis(CVST) in your journal.1 CVST is reported to be commoner indeveloping countries, and has been linked to pregnancy, multiparityand infection.2,3 Developments in imaging, immunology and geneticshave provided valuable information about risk factors and clinicalspectrum of CVST. We report our experience of CVST,  相似文献   
104.

Background

Antimicrobial resistance has decreased eradication rates for Helicobacter pylori infection worldwide. A sequential treatment schedule has been reported to be effective, but studies published to date were performed in Italy. We undertook this study to determine whether these results could be replicated in India.

Methods

A randomized, open-labeled, prospective controlled trial comparing sequential vs. standard triple-drug therapy was carried out at Lokmanya Tilak Municipal General Hospital, Mumbai. Two hundred and thirty-one patients with dyspepsia were randomized to a 10-day sequential regimen (40 mg of pantoprazole, 1 g of amoxicillin, each administered twice daily for the first 5 days, followed by 40 mg of pantoprazole, 500 mg of clarithromycin, and 500 mg of tinidazole, each administered twice daily for the remaining 5 days) or to standard 14-day therapy (40 mg of pantoprazole, 500 mg of clarithromycin, and 1 g of amoxicillin, each administered twice daily).

Results

The eradication rate achieved with the sequential regimen was significantly greater than that obtained with the triple therapy. Per-protocol eradication rate of sequential therapy was 92.4 % (95 % CI 85.8–96.1 %) vs. 81.8 % (95 % CI 73.9–87.8 %) (p?=?0.027) for standard drug therapy. Intention-to-treat eradication rates were 88.2 % (95 % CI 80.9–93.0 %) vs. 79.1 % (95 % CI 71.1–85.4 %), p?=?0.029, respectively. The incidence of major and minor side effects between therapy groups was not significantly different (14.6 % in the triple therapy group vs. 23.5 % in sequential group, p?=?0.12). Follow up was incomplete in 3.3 % and 4.7 % patients in standard and sequential therapy groups, respectively. Sequential therapy includes one additional antibiotic (tinidazole) that is not contained in standard therapy.

Conclusions

Sequential therapy was significantly better than standard therapy for eradicating H. pylori infection.  相似文献   
105.
While elastic modulus is tunable in tissue engineering scaffolds, it is substantially more challenging to tune the Poisson's ratio of scaffolds. In certain biological applications, scaffolds with a tunable Poisson's ratio may be more suitable for emulating the behavior of native tissue mechanics. Here, we design and fabricate a scaffold, which exhibits simultaneous negative and positive Poisson's ratio behavior. Custom-made digital micro-mirror device stereolithography was used to fabricate single- and multiple-layer scaffolds using polyethylene glycol-based biomaterial. These scaffolds are composed of pore structures having special geometries, and deformation mechanisms, which can be tuned to exhibit both negative Poisson's ratio (NPR) and positive Poisson's ratio (PPR) behavior in a side-to-side or top-to-bottom configuration. Strain measurement results demonstrate that analytical deformation models and simulations accurately predict the Poisson's ratios of both the NPR and PPR regions. This hybrid Poisson's ratio property can be imparted to any photocurable material, and potentially be applicable in a variety of biomedical applications.  相似文献   
106.
International Journal of Diabetes in Developing Countries - Patients with diabetic retinopathy (DR) are more likely to have subclinical cardiovascular disease. Objective of this study was to assess...  相似文献   
107.

Purpose

To characterize the degree of venous collateralization before and after endovascular therapy and determine the effect of collateralization on success of thrombolysis and rate of repeat intervention in patients with Paget–Schroetter syndrome.

Materials and Methods

A single-center retrospective study of 37 extremities in 36 patients (mean age, 32.64 y; range, 15–72 y; 24 men) with PSS treated with endovascular therapy from 2007 through 2017 was conducted. Venograms at presentation, after lysis, postoperatively, and at each repeat intervention were graded for venous stenosis, thrombus burden, and collateralization on a 5-point scale. Collateralization was classified as high-grade (9 extremities) or low-grade (28 extremities) based on grading of the venograms at presentation.

Results

Primary technical success rate for endovascular treatment was 100%. Eighty-six percent of patients (32 of 37) underwent thrombolysis, 91% (34 of 37) underwent mechanical thrombectomy, and 83% (30 of 37) underwent balloon angioplasty. Overall primary patency rate was 50% at 12 months. The repeat intervention rate within 12 months was significantly higher for extremities with high- vs low-grade collateralization (89% vs 43%; P = .016). There was a significant decrease in the median grade of collateral severity after initial intervention (2 vs 1; P = .044) and 1 day postoperatively (2 vs 1; P = .040) vs the venogram at presentation.

Conclusions

Severity of venous collateralization on the venogram at presentation of patients with PSS does not appear to affect success of endovascular therapy but may predict long-term patency of affected extremities. Patients in this cohort with severe collateralization on presentation were more likely to need repeat intervention.  相似文献   
108.
OBJECTIVE: To compare the efficacy of two dose and single dose measles vaccination in a community setting. DESIGN: Two community ICDS blocks with populations of 8990 and 8550 children below 12 years of age were selected. Block A had 1560 children between 9 mo to 1 year of age and Block B had 1380 children between the age of 9 mo to 1 year. METHODS: All eligible children between 9 mo to 1 year of age were given measles vaccination in October 1994. Only the children in Group A were given a second dose of measles (as MMR) in April 1995; six months after the first dose. A survey was undertaken from January 1996 to April 1996 to clinically evaluate the number of cases of measles in both these blocks. RESULTS: In Block A 3 children developed measles, whereas in Block B, there were 16 cases of measles (p < 0.01). All other parameters in both groups, e.g., cold chain maintenance were similar. CONCLUSION: This study supports the superiority of two dose measles vaccination given at an interval of 6 months over a single dose measles in a community setting.  相似文献   
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110.
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