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21.
Granulosa Cell Tumors (GCT) constitutes 1.5% to 3.5% of all primary ovarian neoplasms. They may be solid, cystic or both. Unilocular cystic GCT are very rare. We report here a case of 32 years female with unicystic GCT in which the distinction from follicular cyst was difficult and was made by carefully examining the lining of the cyst,which showed occasional multiple layers of granulosa cells with a few Call-Exner bodies.  相似文献   
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This study is concerned with the determination of an optimal appointment schedule in an outpatient-inpatient hospital system where the inpatient exams can be cancelled based on certain rules while the outpatient exams cannot be cancelled. Stochastic programming models were formulated and solved to tackle the stochasticity in the procedure durations and patient arrival patterns. The first model, a two-stage stochastic programming model, is formulated to optimize the slot size. The second model further optimizes the inpatient block (IPB) placement and slot size simultaneously. A computational method is developed to solve the second optimization problem. A case study is conducted using the data from Magnetic Resonance Imaging (MRI) centers of Lahey Hospital and Medical Center (LHMC). The current schedule and the schedules obtained from the optimization models are evaluated and compared using simulation based on FlexSim Healthcare. Results indicate that the overall weighted cost can be reduced by 11.6% by optimizing the slot size and can be further reduced by an additional 12.6% by optimizing slot size and IPB placement simultaneously. Three commonly used sequencing rules (IPBEG, OPBEG, and a variant of ALTER rule) were also evaluated. The results showed that when optimization tools are not available, ALTER variant which evenly distributes the IPBs across the day has the best performance. Sensitivity analysis of weights for patient waiting time, machine idle time and exam cancellations further supports the superiority of ALTER variant sequencing rules compared to the other sequencing methods. A Pareto frontier was also developed and presented between patient waiting time and machine idle time to enable medical centers with different priorities to obtain solutions that accurately reflect their respective optimal tradeoffs. An extended optimization model was also developed to incorporate the emergency patient arrivals. The optimal schedules from the extended model show only minor differences compared to those from the original model, thus proving the robustness of the scheduling solutions obtained from our optimal models against the impacts of emergency patient arrivals.

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Research Objectives: To develop population-based estimates of estrogen replacement therapy use rates in 1995 among women over age 65 living in the community; to estimate the impact of socioeconomic and health characteristics on estrogen use. Method: Estimates are based on a large, nationally representative sample of Medicare beneficiaries; detailed self-report data were merged with Medicare claims. Results: Overall, 13.1% of women reported use of estrogen replacement therapy in 1995. Estrogen users were more likely to be white, age 65–74, with private insurance, high income, history of osteoporosis and heart problems, no history of breast cancer, and a patient of gynecologists. Conclusions: Estrogen use was substantially lower among the socioeconomically disadvantaged, controlling for medical history variables, suggesting considerable inequity in access to estrogen replacement therapy treatment.  相似文献   
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The case is reported of a 37-year-old woman who complained of a gradually progressive mass in the left medial canthus area of one year's duration associated with epiphora. Although the clinical and investigative observations were suggestive of an acquired lacrimal sac cyst, the diagnosis was clinched by the operative and histopathological findings. Excision of the cyst along with dacryocystorhinostomy provided complete cure for this patient.  相似文献   
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The clinical evolution and histological features of skin lesions in a 14-year-old boy were characteristic of self-healing juvenile cutaneous mucinosis. They were (a) early age of onset with fever, (b) plaque lesion over the nape of the neck and thigh, (c) nodular lesions over the scalp, face and periarticular regions and (d) spontaneous resolution.  相似文献   
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Juvenile starry flounder (Platichthys stellatus) and rock sole (Lepidopsetta bilineata) were force-fed 56 Ci each of 1-3H-naphthalene dissolved in salmon oil. Values for radioactivity associated with naphthalene and the metabolite fraction were determined for various tissues and body fluids. Results show that these pleuronectids extensively metabolize dietary naphthalene. The rates of decline in naphthalene concentrations (expressed as disintegrations per minute per milligram of dry tissue) were greater than the rates of decline in metabolite concentrations (dpm/mg) in liver, blood, and skin; therefore, relative proportion of metabolites to naphthalene increased with time and at 168 hr after the initiation of the naphthalene-exposure, more than half of the total radioactivity in both species of fish was associated with the metabolites.Profiles of metabolites in liver, skin, and bile were obtained using thin-layer chromatography. 1,2-Dihydro-1,2-dihydroxynaphthalene constituted 38.7 and 39.7%, respectively, of the total extracted metabolites in livers of the naphthalene-exposed rock sole and starry flounder at 24 hr, whereas the bile from both species contained primarily (>90%) conjugates. From 24 to 168 hr, a significant (P < 0.05) decrease in the proportion of the dihydrodiol derivative and a concomitant increase in the proportion of conjugates—specifically, sulfate/glucoside fraction-were observed with livers of both rock sole and starry flounder. No significant change occurred in the spectrum of biliary metabolites with time. The pattern of metabolites in skin of both species was qualitatively similar to that in liver; however, the proportion of the dihydrodiol was greater in skin than in liver at 24 hr.When naphthalene (56Ci) dissolved in salmon oil was administered to starry flounder via intraperitoneal injection, the extent of biotransformation was less than after dietary exposure. Moreover, metabolites in the livers of the fish in the injection study were predominantly (76.7% of total extracted metabolites) non-conjugates at 24 hr. Once again, from 24 to 168 hr, an increase in the proportion of the sulfate/glucoside fraction and a concomitant decrease in the proportion of the dihydrodiol was observed with liver.These studies demonstrate that the extent of biotransformation of naphthalene and the types of metabolites remaining in tissues (e.g., liver) of flatfish are greatly influenced by both the mode of exposure and the time elapsed after the exposure is initiated. It appears therefore, that different exposures (e.g., in water, food, or sediment) of pleuronectids to polycyclic aromatic hydrocarbons may result in different degrees of alteration in genetic material because of variability in accumulation of non-conjugated metabolites, some of which are implicated in covalent binding with DNA in terrestrial mammals.  相似文献   
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Angiotensin converting enzyme (ACE) inhibitors and dihydropyridine calcium antagonists are well established and widely used as monotherapy in patients with mild to moderate essential hypertension. Earlier studies combining short acting drugs from these classes require multiple dosing and were associated with poor compliance. Availability of longer acting compounds allows once daily administration to avoid the inconvenience of a multiple daily dose. It was decided to perform a randomised double blind, crossover study with the long acting calcium channel blocker amlodipine and the long acting ACE inhibitor lisinopril, given either alone or in combination in essential hypertension. Twenty four patients with diastolic blood pressure (DBP) between 95 and 104 mm Hg received amlodipine 2.5 mg and 5 mg, lisinopril 5 mg and 10 mg, and their combination as per a prior randomisation schedule. Supine and standing blood pressure and heart rate were recorded at weekly intervals. Higher doses of both the drugs individually or in combination were used if the target supine DBP below 90 mm Hg was not achieved. There was a significant additional blood pressure lowering effect with the combination when compared either with amlodipine or lisinopril alone. Five mg amlodipine and 10 mg lisinopril monotherapy achieved the target blood pressure in 71% and 72% patients respectively. The combination of 2.5 mg amlodipine with 5 mg lisinopril produced a much more significant lowering of blood pressure in a higher percentage of patients than that with an individual low dose.  相似文献   
29.
Incomplete hypospadiac urethral duplication with posterior urethral valves   总被引:2,自引:0,他引:2  
Urethral duplication (UD) is an uncommon malformation. Obstruction rarely occurs in hypospadiac UD. We describe two children with incomplete hypospadiac UD in association with posterior urethral valves, a combination not previously recognised. The embryonic significance of this anomaly is discussed. Accepted: 30 September 1997  相似文献   
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