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91.
A series of pyrrolidine-based tartrate diamides having selective tumor necrosis factor-α converting enzyme (TACE) inhibitory activity was selected for the three-dimensional quantitative structure–activity relationship (3D-QSAR) studies. Total 76 compounds were selected by considering a high deviation in the biological activity and structural variations. The quality and predictive power of 3D-QSAR, comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) models for the atom-based, centroid/atom-based, data-based alignments were performed. Various models were developed with the help of these alignments. The best model was developed with data-based alignment. The optimal predictive CoMFA model was obtained with cross-validated r 2 = 0.53 with six component, non-cross-validated r 2 = 0.94, standard error of estimates 0.23, F-value = 121.98 and optimal CoMSIA model was obtained with cross-validated r 2 = 0.53 with five components, non-cross-validated r 2 = 0.93, standard error of estimates = 0.24 and F-value = 138.83. These models also showed the best test set prediction with predictive r 2 value of 0.65 and 0.73, respectively. Thus, on the basis of predictive power COMSIA model appeared to be the best one. The statistical parameters from these models indicate that the data are being well fitted and also have high predictive ability. Moreover, the resulting 3D-CoMFA/CoMSIA contour maps provide useful guidance for designing of highly active TACE inhibitors.  相似文献   
92.

Background

People forget much of what they learn, therefore students could benefit from learning strategies that yield long-lasting knowledge. Yet surprisingly, little is known about how longterm retention is most efficiently mastered. We studied the value of teacher made in class tests as learning aids and compared two types of teacher-made tests (multiple choice and short-answer tests) with a no test (control) to determine their value as aids to retention learning.

Method

The study was conducted on two separate batches of medical undergraduate students. This study compared two types of tests [multiple choice questions (MCQs) and short answer questions (SAQs)] with a no test (control) group. The investigation involved initial testing at the end of the lecture (post instruction), followed by an unannounced delayed retention test on the same material three weeks later. The unannounced delayed test comprising of MCQs and SAQs on the same material was given three weeks later to all the three groups.

Results

In batch I, the MCQ group had a higher mean delayed retention score of 10.97, followed by the SAQ group (8.42) and the control group (6.71). Analysis of variance (ANOVA) test and least significance difference (LSD) post hoc test revealed statistically significant difference between the means of the three groups. Similar results were obtained for batch II

Conclusion

Classroom testing has a positive effect on retention learning; both short-answer and multiple-choice tests being more effective than no test in promoting delayed retention learning, however, multiple-choice tests are better.  相似文献   
93.
Efficacy and safety of 2 herbal products--E-MA-H at 2 dose levels, low (HLD) and high (HHD), and E-MA-HP (HP) capsules--versus placebo (PL) was evaluated in subjects with male sexual dysfunction. Males aged 21-60 with erectile dysfunction, premature ejaculation, or other form of sexual dysfunction were studied in this triple-blind, randomized, placebo-controlled, parallel-groups trial. Subjects received any one of the following 4 interventions: E-MA-H 2 capsules at night (HLD) for 60 days; E-MA-H 2 capsules twice daily for 30 days, followed by 2 capsules at night for 30 days (HHD); E-MA-HP (HP) 2 capsules twice daily for 60 days; or placebo (PL) 2 capsules twice daily for 60 days. All dosage regimens were standardized to 2 capsules twice daily by using 2 matching placebo capsules as the morning dose for HLD and on days 31-60 for HHD. Efficacy outcome measures were the international index of erectile function; index for premature ejaculation; erectile dysfunction inventory of treatment satisfaction; subjects' and investigators' global assessment. Safety was assessed through adverse events; hematology; blood chemistry. Of 148 subjects enrolled, 1 was excluded from analysis; data on the intention-to-treat population of 147 (PL = 36, HLD = 38, HHD = 37, HP = 36) were analyzed. There was a significant (P < 0.01) increase in the total international index of erectile function score (mean ± SEM) in subjects receiving HLD (16.28 ± 1.39), HHD (15.40 ± 1.22), and HP (18.55 ± 1.36) compared with PL (6.83 ± 1.52). The same pattern was seen with increase in index for premature ejaculation scores: HLD (9.68 ± 1.17), HHD (10.27 ± 1.05), HP (11.36 ± 1.20) versus PL (3.77 ± 1.04). There was no significant difference in effect among the active treatment groups. The incidence of adverse events was similar in all the groups. Laboratory evaluations did not show any clinically significant abnormality in any of the groups. Treatment with HLD, HHD, and HP is well tolerated, and more effective than placebo (P < 0.01), in subjects with erectile dysfunction, premature ejaculation, and other forms of sexual dysfunction.  相似文献   
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95.

Background:

In women, cancer of the breast is one of the most common incident cancer and cause of death from cancer. Anthropometric factors of weight, height, and body mass index (BMI) have been associated with breast cancer risk.

Objectives:

To study the association of overweight and obesity with breast cancer in India.

Materials and Methods:

A hospital-based matched case-control study was conducted. Three hundred and twenty newly diagnosed breast cancer patients and three hundred and twenty normal healthy individuals constituted the study population. The subjects in the control group were matched individually with the patients for their age ±2 years and socioeconomic status. Anthropometric measurements of weight and height were recorded utilizing the standard equipments and methodology. The paired ‘t’ test and univariate logistic regression analysis were carried out.

Results:

It was observed that the patients had a statistically higher mean weight, body mass index, and mid upper arm circumference as compared to the controls. It was observed that the risk of breast cancer increased with increasing levels of BMI. Overweight and obese women had Odd''s redio of 1.06 and 2.27, respectively, as compared to women with normal weight.

Conclusions:

The results of the present study revealed a strong association of overweight and obesity with breast cancer in the Indian population.  相似文献   
96.

Introduction

Surgical repair of the tympanic membrane, termed a type one tympanoplasty is a tried and tested treatment modality. Overlay or underlay technique of tympanoplasty is common. Sandwich tympanoplasty is the combined overlay and underlay grafting of tympanic membrane.

Objective

To describe and evaluate the modified sandwich graft (mediolateral graft) tympanoplasty using temporalis fascia and areolar fascia. To compare the clinical and audiological outcome of modified sandwich tympanoplasty with underlay tympanoplasty.

Methods

A total of 88 patients of chronic otitis media were studied. 48 patients (Group A) underwent type one tympanoplasty with modified sandwich graft. Temporalis fascia was underlaid and the areolar fascia was overlaid. 48 patients (Group B) underwent type one tympanoplasty with underlay technique. We assessed the healing and hearing results.

Results

Successful graft take up was accomplished in 47 patients (97.9%) in Group A and in 40 patients (83.3%) Group B. The average Air-Bone gap closure achieved in Group A was 24.4 ± 1.7 dB while in Group B; it was 22.5 ± 3.5 dB. Statistically significant difference was found in graft healing rate. Difference in hearing improvement was not statistically significant.

Conclusion

Double layered graft with drum-malleus as a ‘meat’ of sandwich maintains a perfect balance between sufficient stability and adequate acoustic sensitivity.  相似文献   
97.
Early-stage non-small cell lung cancer (NSCLC) is on the rise due to the implementation of screening guidelines for patients at risk for developing lung cancer. It is anticipated that as the US population continues to age, there will be a higher percentage of medically inoperable early-stage lung cancer patients. For this reason, noninvasive ablative therapies are necessary. Stereotactic body radiation therapy (SBRT) is an effective modality in addressing early-stage NSCLC. SBRT consists of high-dose radiation delivered over 3–5 treatments. Several randomized trials comparing surgery to SBRT in early-stage operable patients have unfortunately closed early due to poor accrual. However, a recent pooled analysis from 2 randomized trials (StereoTActic Radiotherapy and Radiosurgery Or Surgery for operable Early-stage non–small cell Lung cancer) comparing surgery to SBRT did show comparable local control and overall survival rates between surgery and SBRT, offering a very effective, noninvasive modality for older adult patients with early-stage NSCLC. In this review, we summarize the role of SBRT in early-stage NSCLC, in particularly applied to the older adult population.  相似文献   
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