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391.
Before the 1950s effective medical interventions were not available and epidemiological transition in developing countries was mostly initiated by the introduction of mains water, sewage systems and personal hygiene. Nowadays, effective medical interventions such as vaccination programmes, medication and vitamin supplements might aid a swift transition. We recorded mortality among a research population of 18850 in Garu-Tempane district of Ghana from 2002 to 2005. We calculated the expected mortality based on the population structure in 2002 and compared the life expectancy of the region with other countries depending on their gross domestic product (GDP). Mortality in the age group 0-9 years was 8.1 per 1000 person-years and in the age group 10-19 years it was 4.1 per 1000 person-years. Cumulative survival probability up to age 20 years amounted to 89% and was far higher than expected. Observed and expected mortality in old age were similar. The life expectancy at birth was 59 years and much higher than the region's per capita annual income of US$100 would predict. We conclude that the population is in epidemiological transition. It shows that an epidemiological transition can be accelerated with low-cost interventions.  相似文献   
392.
OBJECT: The aim of this study was to determine prognostic factors for outcome after transsphenoidal hypophysectomy in dogs with pituitary-dependent hyperadrenocorticism (PDH). METHODS: One veterinary neurosurgeon performed transsphenoidal hypophysectomies in 181 dogs with PDH over a 12-year period. Survival analysis was performed with the Kaplan-Meier method. Prognostic factors were analyzed with the univariate Cox proportional hazard analysis followed by stepwise multivariate analysis. The log-rank test was used to assess disease-free fractions in three groups categorized according to early postoperative urinary corticoid/creatinine (C/C) ratios. RESULTS: Multivariate analysis revealed that old age, large pituitary size, and high preoperative concentrations of plasma adrenocorticotropic hormone were associated with an increased risk of PDH-related death. In addition, large pituitary size, thick sphenoid bone, high C/C ratio, and high concentration of plasma alpha-melanocyte-stimulating hormone (alpha-MSH) before surgery were associated with an increased risk of disease recurrence in the dogs that went into remission after hypophysectomy. Disease-free fractions were significantly higher in dogs with postoperative urinary C/C ratios in the lower normal range (< 5 x 10(-6)) than in dogs with postoperative C/C ratios in the upper normal range (5-10 x 10(-6)). CONCLUSIONS: The results of this study indicate that pituitary size, sphenoid bone thickness, plasma alpha-MSH concentration, and preoperative level of urinary cortisol excretion are predictors of long-term remission after transsphenoidal hypophysectomy for PDH in dogs. Urinary C/C ratios measured 6 to 10 weeks after surgery can be used as a guide for predicting the risk of tumor recurrence.  相似文献   
393.
Objective: Gender differences exist in the prevalence and psychiatric comorbidity of major depressive disorder (MDD). This study investigates whether familiality of MDD contributes to observed gender differences in comorbidity. Method: Familial (f‐MDD) and non‐familial (nf‐MDD) MDD cases from a population sample were assessed for comorbid dysthymia, anxiety disorders and alcohol‐related disorders using the Composite International Diagnostic Interview (CIDI). Logistic regression analyses were performed to examine the effect of f‐MDD on gender differences in comorbidity, adjusted for confounders. Results: Women with f‐MDD reported significantly more comorbid dysthymia and generalized anxiety disorder (GAD) than their male counterparts; women with nf‐MDD reported significantly more comorbid simple phobias and agoraphobia than their male counterparts. Gender differences in comorbid panic disorder and alcohol‐related disorders occurred independently of the familial load. Adjustment for age of onset, severity and recurrence of MDD did not change these results. Conclusion: Models to explain comorbidity patterns of MDD differ by gender. Familiality of MDD should be taken into account.  相似文献   
394.
L1 elements are autonomous retrotransposons that can cause hereditary diseases. We have previously identified a full-length L1 insertion in the CHM (choroideremia) gene of a patient with choroideremia, an X-linked progressive eye disease. Because this L1 element, designated L1(CHM), contains two 3'-transductions, we were able to delineate a retrotransposition path in which a precursor L1 on chromosome 10p15 or 18p11 retrotransposed to chromosome 6p21 and subsequently to the CHM gene on chromosome Xq21. A cell culture retrotransposition assay showed that L1(CHM) is one of the most active L1 elements in the human genome. Most importantly, analysis of genomic DNA from the CHM patient's relatives indicated somatic and germ-line mosaicism for the L1 insertion in his mother. These findings provide evidence that L1 retrotransposition can occur very early in human embryonic development.  相似文献   
395.
Injuries to the intervertebral disc caused by degeneration or trauma often lead to tearing of the annulus fibrosus (AF) and extrusion of the nucleus pulposus (NP). This can compress nerves and cause lower back pain. In this study, the characteristics of poly(d,l-lactide-co-trimethylene carbonate) networks with shape-memory properties have been evaluated in order to prepare biodegradable AF closure devices that can be implanted minimally invasively. Four different macromers with (d,l-lactide) to trimethylene carbonate (DLLA:TMC) molar ratios of 80:20, 70:30, 60:40 and 40:60 with terminal methacrylate groups and molecular weights of approximately 30 kg mol−1 were used to prepare the networks by photo-crosslinking. The mechanical properties of the samples and their shape-memory properties were determined at temperatures of 0 °C and 40 °C by tensile tests- and cyclic, thermo-mechanical measurements. At 40 °C all networks showed rubber-like behavior and were flexible with elastic modulus values of 1.7–2.5 MPa, which is in the range of the modulus values of human annulus fibrosus tissue. The shape-memory characteristics of the networks were excellent with values of the shape-fixity and the shape-recovery ratio higher than 98 and 95%, respectively. The switching temperatures were between 10 and 39 °C. In vitro culture and qualitative immunocytochemistry of human annulus fibrosus cells on shape-memory films with DLLA:TMC molar ratios of 60:40 showed very good ability of the networks to support the adhesion and growth of human AF cells. When the polymer network films were coated by adsorption of fibronectin, cell attachment, cell spreading, and extracellular matrix production was further improved. Annulus fibrosus closure devices were prepared from these AF cell-compatible materials by photo-polymerizing the reactive precursors in a mold. Insertion of the multifunctional implant in the disc of a cadaveric canine spine showed that these shape-memory devices could be implanted through a small slit and to some extent deploy self-sufficiently within the disc cavity.  相似文献   
396.
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