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971.
Seventy-two recent-onset injection drug users and 241 non-injection drug users were recruited in Quetta and Lahore, Pakistan, in 2003. Trained interviewers administered questionnaires regarding drug use behaviors and perceived changes in drug cost/supply. Logistic regression identified independent correlates of recent-onset injection. In Lahore, a perceived increase in drug cost was associated with higher odds of recent-onset injection, with no association in Quetta. Recent-onset injection was also associated with family history of drug use, group drug use, and sharing snorting/chasing tools. Changes in perception of the drug supply may be associated with recent-onset injection drug use. Familial/social influences were also associated with recent-onset injection, suggesting peer-led interventions could discourage transition to injection drug use.  相似文献   
972.
973.
This is the report of a 6 months old boy presenting with a firm, solitary mass on the temporal region, associated with lysis of local bone. Investigations lead to a diagnosis of infantile myofibromatosis (IM). Wide local excision was performed. At one year follow-up, no recurrence was noted.  相似文献   
974.
Acardiac twinning is a severe and rare complication of monochorionic placentation. The acardiac twin does not survive while mortality of the normal twin is about 50-70% as the normal twin has to provide circulation not only for itself but also for acardiac twin. Proper timing of the delivery is of prime importance to the survival of the normal fetus for which emphasis is placed on close sonographic monitoring for early antenatal diagnosis. This series describes three such cases, which are now termed Twin Reversed Arterial Perfusion (TRAP) sequence.  相似文献   
975.
Objective: To determine the postoperative analgesic effect of Tramadol when given with caudally administered Bupivacaine in children undergoing inguinoscrotal surgeries. Study Design: Quasi-experimental study. Place and Duration of Study: Department of Anaesthesia, Dow University of Health Sciences and Civil Hospital Karachi, from July 2005 to March 2006. Patients and Methods: A total of 60 children, undergoing inguinoscrotal surgeries, aged from 1 to 12 years, ASA 1 and 2, were included. The patients were divided into two equal groups. The group given Bupivacaine with Tramadol was called 'group BT' and the group which was given only Bupivacaine was labeled as 'group B'. Group BT was given 0.25%,0.8 ml/kg Bupivacaine and Tramadol 2 mg/kg while the other group B was given 0.25%, 0.8 ml/kg Bupivacaine through caudal route after induction of general anesthesia. No other analgesic was given intraoperatively. The postoperative pain was evaluated by using visual analogue scale/Ocher's face scale/CHEOPS and sedation was assessed by 5 points sedation score at immediate postoperative period 1, 2,3,4,6, 12 and 24 hours. Supplemental analgesia in the form of paracetamol suppositories and syrup Ibuprofen was given accordingly. SaO2, pulse, blood pressure, and motor block were monitored in all the patients. Results: Addition of Tramadol with Bupivacaine resulted in meaningfully increased postoperative analgesic period (16.06 +/- 4.04 hours). No other side effects like respiratory depression, pruritus, urinary retention were found in both the groups except for nausea and vomiting. The demand for supplemental analgesia was more in the patients belonging to B group than BT group. The sedation scores were similar in both the groups. Conclusion: The use of Tramadol as an additive with local anesthetics can prolong the postoperative analgesic period when administered caudally. Its use is safe in children.  相似文献   
976.
A 25 years old lady with vaginal atresia, secondary to a mismanaged spontaneous vaginal delivery, underwent vaginoplasty using human amnion. The amnion was kept in its place using a 60cc syringe as a mould. For the next three months, dilatation by soft mould was followed by regular intercourse. Alongwith the restoration of normal coital function, she also conceived and was delivered by planned caesarean section at 38 weeks.  相似文献   
977.
The role of NMDA receptors in the induction of long-term potentiation (LTP) and long-term depression (LTD) is well established but which particular NR2 subunits are involved in these plasticity processes is still a matter of controversy. We have studied the effects of subtype selective NMDA receptor antagonists on LTP induced by high frequency stimulation (100 Hz for 1s) and LTD induced by low frequency stimulation (1 Hz for 15 min) in the CA1 region of hippocampal slices from 14 day old Wistar rats. Against recombinant receptors in HEK293 cells NVP-AAM077 (NVP) was approximately 14-fold selective for NR2A vs NR2B receptors, whilst Ro 25-6981 (Ro) was highly selective for NR2B receptors. On NMDA receptor-mediated EPSCs from Schaffer collaterals in CA1 neurones, NVP and Ro both reduced the amplitude but differentially affected the time constant of decay. The data are compatible with the selective effect of NVP (0.1 microM) and Ro (4 microM) on native NR2A and NBR2B receptors, respectively. NVP reduced both LTP and LTD whereas Ro reduced only LTP. Thus, LTP was reduced by 63% at 0.1 microM NVP and almost completely at 0.4 microM whereas 5 microM Ro reduced LTP by 45%. These data are consistent with a role for both NR2A and NR2B in the induction of LTP, under our experimental conditions. In comparison, LTD was unaffected by Ro (5 microM) even in the presence of a glutamate uptake inhibitor threo-beta-benzylaspartic acid (TBOA) to increase the concentration of glutamate at NR2B containing receptors. NVP (0.2-0.4 microM), however, produced a concentration dependent inhibition of LTD which was complete at 0.4 microM. The lack of effect of 0.1 microM NVP on LTD contrasts with its marked effect on LTP and raises the possibility that different NVP-sensitive NR2 subunit-containing NMDA receptors are required for LTP and LTD in this preparation.  相似文献   
978.
BACKGROUND: To assess injection practices and to test interventions aimed at reducing unsafe injections in developing countries, cluster surveys and cluster randomized trials are needed. The design of cluster-based studies requires estimates of intraclass correlation coefficients that have to be obtained from previous studies. This study presents such estimates. METHODS: Data were derived from a cross-sectional study of injection use and health seeking in Pakistan that used 34 clusters to select 1150 study subjects aged > or =3 months. We analysed variance to separate its components. RESULTS: Most of intraclass correlation coefficients were in the range of 0.01-0.05. For proportion of injections received during last 3 months, mean number of injections received and health seeking during the past 3 months the intraclass correlation coefficients were 0.02, 0.04 and 0.02, respectively. CONCLUSION: These estimates can be useful in designing cluster surveys and cluster randomized trials for injection safety in Pakistan and other developing countries.  相似文献   
979.
980.
In this work, the 3D proton dose profile is calculated in a homogenous water phantom using a Monte Carlo application developed with the Geant4 toolkit. The effect of the ridge filter material (for SOBP widths of 6, 9 and 12cm) on the homogeneity of the dose distribution, secondary neutron production and beam efficiency are investigated in a single ring wobbling irradiation system. The energy spectrum of secondary neutrons per primary proton at various locations around the phantom surface is calculated. The simulation revealed that most of the produced neutrons are released at slight angles which enable them to reach the patient and consequently to be hazardous. Also, the homogeneity of the dose distribution at the proximal edge of spread out Bragg peak (SOBP) field is deteriorated due to the scattering of protons in the ridge filter. It is found that for reducing the above mentioned destructive effects, usage of a PMMA ridge filter is better than Al one. For a similar value of 9cm water equivalent thickness, beam widening radius of Al at isocenter is twice of PMMA. Furthermore, for uniform irradiation of the target, the beam efficiency of the system for Al is less than of PMMA and also regarding to the secondary neutron production PMMA is a better choice.  相似文献   
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