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Background

Long-acting reversible contraceptives, such as the intrauterine device (IUD), remain underutilised in Pakistan with high discontinuation rates. Based on a 24-month prospective client follow-up (nested within a larger quasi-experimental study), this paper presents the comparison of two intervention models, one using private mid-level providers branded as “Suraj” and the other using community midwives (CMWs) of Maternal Newborn and Child Health Programme, for method continuation among IUD users. Moreover, determinants of IUD continuation and the reasons for discontinuation, and switching behaviour were studied within each arm.

Methods

A total of 1,163 IUD users, 824 from Suraj and 339 from the CMW model, were enrolled in this 24-month prospective client follow-up. Participants were followed-up by female community mobilisers physically every second month to ascertain continued IUD usage and to collect information on associated factors, switching behaviour, reasons for discontinuation, and pregnancy occurrence. The probabilities of IUD continuation and the risk factors for discontinuation were estimated by life table analysis and Cox proportional-hazard techniques, respectively.

Results

The cumulative probabilities of IUD continuation at 24 months in Suraj and CMW models were 82% and 80%, respectively. The difference between the two intervention areas was not significant. The probability distributions of IUD continuation were also similar in both interventions (Log rank test: χ2 = 0.06, df = 1, P = 0.81; Breslow test: χ2 = 0.6, df = 1, P = 0.44). Health concerns (Suraj = 57.1%, CMW = 38.7%) and pregnancy desire (Suraj = 29.3%, CMW = 40.3%) were reported as the most prominent reasons for IUD discontinuation in both intervention arms. IUD discontinuation was significantly associated with place of residence in Suraj and with age (15–25 years) in the CMW model.

Conclusion

CMWs and private providers are equally capable of providing quality IUD services and ensuring higher method continuation. Pakistan’s National Maternal Newborn and Child Health programme should consider training CMWs and providing IUDs through them. Moreover, private sector mid-level providers could be engaged in promoting the use of IUDs.

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Brain Imaging and Behavior - Cognitive impairment is now recognized in a subset of patients with amyotrophic lateral sclerosis (ALS). The objective of the study was to identify group differences...  相似文献   
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The hydrothermal method was used to create dilute magnetic semiconductor nanoparticles of Zn1−xCoxO (x = 0, 0.01, 0.05, 0.09). The effect of cobalt doping on the microstructure, morphological and optical properties of Zn1−xCoxO was also studied and the Co doping to host ZnO was confirmed from XRD and EDX analysis. The structural analysis showed that doping of cobalt into ZnO decreased the crystallinity, but the preferred orientation didn''t change. SEM analysis revealed that the cobalt dopant did not have a strong influence on the shape of the synthesized nanoparticles. No defect-related absorption peaks were observed in the UV-Vis spectra. The crystallinity of the doped samples was improved by high growth temperature and long growth time. Ferromagnetic behavior above room temperature was detected in co-doped ZnO nanoparticles. The ferromagnetic behavior increased with increasing Co (up to x = 0.05) doping. The ferromagnetic behavior declined when the Co content was further increased. Related research shows that doped ZnO nanoparticles have better dielectric, electrical conductivity, and magnetic properties than pure ZnO. This high ferromagnetism is usually a response reported for dilute magnetic semiconductors. These semiconductor nanoparticles were further used to designed spintronic based applications.

The enlarged central part MH loop shows for the Co = 0.09 doped ZnO sample, the ferromagnetic (FM) behavior increased, i.e., a Mr of 0.2412 emu g−1 with a Hc of 85 Oe.  相似文献   
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Background  

Gemstones have been in use as part of alternative and complementary medicine for years. However, our understanding of the perceived healing powers of gemstones is limited. An extensive literature search revealed that there is a dearth of validated information on this subject. This study was therefore undertaken to explore the various aspects of the knowledge, attitudes, and practices of the public towards gemstone therapeutics.  相似文献   
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Guidance of percutaneous pulmonary biopsies with real-time CT fluoroscopy   总被引:5,自引:0,他引:5  
OBJECTIVE: Clinical evaluation of computed tomography (CT) fluoroscopy and comparison with conventional CT guidance for monitoring of percutaneous pulmonary biopsy procedures. METHODS: Twenty CT-guided pulmonary biopsy procedures were conducted. The interventions have prospectively been performed either with CT fluoroscopy or with conventional CT guidance. About 120 kV and 50 mA with a frame-rate of eight images per second were used for CT fluoroscopy. Number of pleural needle passages, procedure times, radiation doses and histologic results were analyzed separately for both methods. RESULTS: Compared with conventional CT guidance, CT fluoroscopy was associated with less pleural needle passages (1.8+/-0.6 vs. 1.1+/-0.3; P=0.003, t-test) and procedure times were shorter than for conventional CT guidance (12.7+/-2.2 min vs. 26.7+/-16.4 min; P=0.02). Analysis of estimated patient related radiation exposure and histologic outcome showed no significant difference between conventional and fluoroscopic CT-guided procedures (P>0.05). CONCLUSION: CT fluoroscopy facilitates guidance of percutaneous pulmonary biopsy procedures. Compared with conventional CT assistance, procedure times are decreased and less pleural needle passages are required. While patient-related radiation exposure is similar, operator-related radiation exposure remains a disadvantage associated with CT fluoroscopy.  相似文献   
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Mycobacterium lepraemurium was cultivated on Ogawa egg-yolk medium and its energy coupling mechanisms were investigated. Cell-free extracts prepared from in vitro-grown cells catalyzed phosphorylation coupled to the oxidation of generated NADH, added NADH, and succinate-yielding ratios of phosphorus moles incorporated into high-energy bonds to oxygen atoms utilized (P/O ratios) of 0.75, 0.52, and 0.36, respectively. Ascorbate oxidation alone or in the presence of tetramethyl-p-phenyline-diamine (TMPD) did not yield any adenosine triphosphate (ATP). However, ascorbate in the presence of added cytochrome c was coupled to ATP synthesis and yielded a P/O ratio of 0.12. The oxidative phosphorylation was uncoupled by all of the uncouplers used without any inhibition of oxygen consumption. ATP generation coupled to NADH oxidation was completely inhibited by the flavoprotein inhibitors, such as rotenone and amytal; these inhibitors had no effect, however, on ATP synthesis associated with succinate oxidation. Antimycin A or 2-n-heptyl-4-hydroxy-quinoline-N-oxide (HQNO) and cyanide inhibited markedly the oxidations of NADH and succinate as well as the coupled ATP generation. The phosphorylation coupled to ascorbate plus cytochrome c was not affected by either of the flavoprotein inhibitors or by antimycin A or HQNO, but was completely inhibited by cyanide. The thiol-bearing agents p-chloromercuribenzoate (PCMB) and N-ethylmaleimide were the potent inhibitors of the phosphorylation associated with the oxidation of NADH and succinate. The results indicate that the three energy-coupling sites are functional in the respiratory chain of in vitro-grown M. lepraemurium.  相似文献   
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