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991.
992.
A HPLC method has been described for simultaneous determination of Losartan potassium and Metolazone in formulation. This method is based on a HPLC separation of the two drugs on the Thermo Hypersil BDS-C(18) (250 mm × 4.6 mm, 5.0 μm) with isocratic conditions and a simple mobile phase containing acetonitrile:water (60:40) at a flow rate of 0.8 mL/min using UV detection at 237 nm. This method has been applied to a marketed formulation without interference of excipients. The linear regression analysis data for the calibration plots showed a good linear relationship over the concentration range of 2-12 μg/mL for Losartan potassium and 0.2-1.2 μg/mL for Metolazone, respectively. The method was validated for precision, robustness and recovery. Statistical analysis showed that the method is repeatable and selective for the estimation of Losartan potassium and Metolazone.  相似文献   
993.

Objective:

Human experimental pain models help to understand the mechanism of the painful conditions and can also be adopted to test analgesic efficacy of drugs. In early phases, the clinical development of new analgesics is hindered due to the lack of reliable tests for the experimental pain models. In the present study, we have developed and validated a simple radiant heat pain model which can be used for future screening of various analgesic agents.

Materials and Methods:

We have standardized the thermal pain model by recording pain threshold and pain tolerance time in seconds at three different intensities and levels in 24 healthy subjects. Reproducibility of the test procedure was evaluated by recording the pain parameters by two observers on three consecutive days. Validity of model was further tested by evaluating the analgesic effect of tramadol.

Results and Conclusions:

Use of radiant heat pain model with high intensity and short level was found to produce low variability with coefficient of variation less than 5%. Interobserver and interperiod reproducibility was very good as shown by Bland - Altman plot; with most of the values within ± 2SD. Tramadol produced statistically significant increase in pain threshold time. The newly developed pain model produces a type of experimental pain which is responsive to analgesic effects of tramadol at clinically relevant doses.KEY WORDS: Healthy subjects, thermal pain model, tramadol  相似文献   
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995.
Poorly differentiated carcinomas of the thyroid have evolved over the past half century into a specific entity in the classification of thyroid carcinomas. The need for a consensus diagnostic criteria has been stressed in view of the wide discrepancies and confusion among pathologists and clinicians. This review attempts to understand the concept, the evolution, clarity and validity of the concepts in poorly differentiated carcinomas of the thyroid.  相似文献   
996.
The use of clinicopathologic features in decision-making in early stage estrogen receptor (ER)-positive breast cancer (BC) may lead to over or under treatment. We investigated the effect of the Oncotype Dx? (ODX) on chemotherapy (CTX) utilization in two cancer centers. 276 cases of node-negative ER-positive BC had ODX between 2005 and 2009. Age at diagnosis, tumor size, grade, and progesterone receptor (PR) status were abstracted from records and provided to two medical oncologists blinded to the ODX score. A recommendation for or against CTX was made based on clinicopathologic characteristics. Median age was 55 years. Mean tumor size was 1.6 cm. The median 10-year Adjuvant! Online (AO) mortality risk was 8. The median Nottingham Prognostic Index (NPI) was 3.3. The median ODX recurrence score was 17. Without knowledge of the ODX, oncologists were more likely to recommend CTX to younger women (P < 0.0001), women with negative PR status (P < 0.0001), higher NPI (P < 0.012), and tumors > 1 cm (P = 0.033). On average, CTX recommended patients had larger tumors (2.0 vs. 1.2 cm) and higher AO 10-year mortality (11.4 vs. 4.4%). ODX resulted in a change in management for 38% of women. Of 188 total patients who did not receive CTX, 71 had a recommendation favoring CTX by an oncologist blinded to the ODX score. In our multi-institutional cohort, the ODX score had a significant impact on the receipt of adjuvant CTX and altered management for 38% of women.  相似文献   
997.
A growing number of young breast cancer survivors consider reproductive health issues, including subsequent fertility and pregnancy, of great importance, but many questions regarding safety remain unanswered. We conducted a comprehensive literature search and review of published articles, control-matched, population-based, and co-operative group reports that addressed various aspects of pregnancy after breast cancer (patients’ expectations, fertility damage, assessment and preservation, maternal and fetal outcome, breast feeding). Overall, available data support pregnancy and breast feeding after breast cancer as safe and feasible for women at low risk of recurrence. This retrospective and population-based evidence is, however, frequently incomplete; usually not representative of the entire population, it can be biased by patients’ related effects or underpowered and is often not controlled for biological factors and risk determinants in the statistical model used. Before making any definitive assumption on this delicate and fundamental aspect of a woman’s life after breast cancer, we should demonstrate without any reasonable doubt that the scattered information available today is scientifically sound. The Breast International Group and North American Breast Cancer Group are planning a global prospective study in young women with endocrine responsive, early breast cancer who desire pregnancy, to assess both patients’ and pregnancy outcomes. The trial will include an observational phase investigating the feasibility and impact of a temporary treatment interruption to allow conception and an experimental phase investigating the optimal duration of the subsequent endocrine treatment after delivery or the last failed attempt to get pregnant.  相似文献   
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999.
1000.
Treatment and reconstruction of oral scar contracture, is always a challenging procedure to restore structure and functions of the oral cavity. We present a case of a patient with limited mouth opening who sustained extensive oral scar contracture with complete adhesion of tongue to floor of mouth following ingestion of caustic soda without his knowledge 4 years back. We performed a surgical release of the scar contractures from buccal mucosa on both sides, along with a release of the tongue from the floor of the mouth, followed by reconstruction of all sites using split skin grafts. Adequate mouth opening and tongue movement was achieved. There was a follow up period of 1 month with excellent mouth opening and tongue function.  相似文献   
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