BACKGROUND AND OBJECTIVE: In patients with unilateral or bilateral loss with high length (more than 10cm) and with different etiologies, ileal substitution is good alternative when other procedures are not suitable. The objective of this study was to survey the effects and complications of ileal substitution for urethral loss. CASES: Sixteen patients were operated in urologic ward of Shahid Labbafinejad hospital with ileal substitution for urethral loss during 1994-1999. Twelve patients were male and four were female with mean age 28 years (3-47 years). Etiology was complications of surgery and ureterscopy in 11 and T.B in 2 and ureteral avulsion in one due to trauma. Follow up was 9-60 months and 3 patients missed follow up. Pre. op sonography, I.V.P. and D.T.P.A isotope scan in all patients revealed severe hydronephrosis in 11 patients. Post.op sonography and scan showed much improvement of kidney function. In 2 patients, hydronephrosis persisted that nephrectomy was performed. CONCLUSION: In cases with high ureteral loss which other procedures like uretero-ureterostomy or transuretero ureterostomy or autotransplant or kidney descending or Boari-Flap cannot be done, ileal substitution is good alternative with low complication

YBa2-xKxCu3O7-8 compound with x = 0, 0.1, 0.15, 0.2, 0.3, 0.5, 0.8, 1 was prepared. The samples were characterized by XRD, Tc, oxygen content and room temperature thermopower measurements. The results shows that by increasing the potassium, the samples go to the underdoped regime. This is due to the depletion of oxygen from the samples. By post annealing of the sample with x = 0.2 and Tc = 78 K in oxygen, the Tc increased up to 93 K which means it is possible to put back the oxygens into the structure.

If a country's domestic currency fails to perform its functions, foreign currency substitution occurs. This phenomenon is common in developing countries and is influenced by various economic and political factors. The main objective of this research is to estimate the relationship between exchange rate overshooting and currency substitution in Iran. We first use the Kamin & Ericsson method (2003) to evaluate the amount of circulating foreign currency and currency substitution within the Iranian economy, using annual data from 1979 to 2020. Then, we apply the ARDL method to estimate the impact of exchange rate overshooting on currency substitution. The long-term results indicate that exchange rate overshooting consistently increases currency substitution in Iran. Conversely, gross domestic product negatively affects currency substitution, while war and sanctions moderate this effect. Furthermore, the impact of war is greater than that of sanctions. According to the error correction coefficient (-0.92), it takes about 13 months to reach long-term equilibrium. Understanding the relationship between currency substitution and overshooting helps policymakers design better strategies for managing exchange rates and monetary policy.

Using the currency substitution theory, this paper attempts to identify the determinants of currency substitution degree in Iran. The hypotheses of this paper are: 1-In Iranian economy the trend of currency substitution has been ascending. 2-There is a direct relationship between the degree of currency substitution and domestic inflation rate of the country (CPI). 3-The degree of currency substitution has an indirect relationship with the foreign exchange rate in the parallel market. 4- The degree of currency substitution in Iran has a direct relationship with GDP. The results reveal that the first and second hypotheses were verified and the third and fourth ones assumed not to be valid. Despite the reduction in the volume of dollar in some years, the trend of currency substitution has been increasing.

Objective: Silicon is an effective element in bone biomineralization; hence Si-substituted hydroxyapatite can be a relevant bioceramic as bone materials substitution.Materials and Methods: Stoichiometric hydroxyapatite (HA) and Si-substituted hydroxyapatite (Si-HA) with different contents of Si substitution were synthesized successfully by a hydrothermal method using Ca(NO3)2, (NH4)3PO4 or (NH4)2HPO4 and Si(OCH2CH3)4 (TEOS) as starting materials.Results: Crystalline Phases, chemical composition, microstructure and morphology of synthesized powders were investigated using X-ray diffraction (XRD), Fourier transform IR spectroscopy (FTIR), inductively coupled plasma AES (ICP-AES) and scanning electron microscopy (SEM) techniques. The results proved silicon substitution in hydroxyapatite structure and revealed that the substitution of phosphate groups by silicate groups caused some OH- loss to maintain charge balance and the lattice parameters slightly changed with respect to stoichiometric HA.Conclusion: Si-incorporation reduces the crystallites size of Si-HA and crystallinity, thus the solubility of Si-HA powders increases, and as a result Si- substitution has improved bioactivity behavior of HA. Based on in-vitro tests; soaking and incubating the specimens in simulated body fluid (SBF) and MTT assays (Dimethylthiazol assay), Si-substituted hydroxyapatite is more bioactive than pure hydroxyapatite.

Methadone is widely being used for opioid substitution therapy. However, the administration of methadone to opioid dependent individual is frequently accompanied by withdrawal syndrome and chemical dependency develops. Other than that, it is also difficult to retain patients in the treatment programme making their retention rates are decreasing over time. This article is written to higlights the potential use of prophetic medicines, Nigella sativa, as a supplement for opioid dependent receiving methadone. It focuses on the potential role of N. sativa and its major active compound, Thymoquinone (TQ) as a calcium channel blocking agent to reduce withdrawal syndrome and opioid dependency.