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1.
Background: The Tubu are nomadic people who live in remote parts of the central Sahara, primarily in the Tibesti massif(Chad), and in both Northeastern Niger and Southern Libya. All of these areas are close to become conflict zones. However, no data about the Tubu’s health and sanitary status are currently available, which would be of major concern if humanitarian interventions would become required.Methods: In 1970, the "Mission Anthropologique Belge au Niger"(MABN) investigated a Tubu tribe named Broaya that lived at Seguedine and Djado on the northeastern rim of the Tenere desert. One hundred fifty-one adult volunteers answered an oral questionnaire and underwent a medical examination, followed by the collection of blood thin films and samples of urine and stool. The environmental fauna of medical importance was also studied.Results: Albeit 43 year-old, these results have not been previously published. The estimated age of death for fathers was approximately 56 years, and that for mothers was 60 years. On average, each married woman had had 4.7 children. The overall perinatal mortality rate was 232 ‰, the overall infant mortality rate was 153 ‰, and the overall child mortality rate was 99 ‰. The mean height was 164.1 cm and 157.4 cm, the mean weight was 50.1 kg and 47.9kg, and the mean blood pressure was 131/78 mm Hg and 127/75 mm Hg for males and females, respectively. The physical examination found 6 cases of blindness(4.0%). Five subjects presented with an elevated blood pressure(3.3%), and 5(3.3%) displayed an abnormal thoracic auscultation evocative of tuberculosis or of an acute lung infection. The abdominal examination and renal palpation found 5 large masses(3.3%), and 2 subjects had a palpable enlarged spleen(1.3%). The blood thin films were fixed in methanol and subsequently examined in Toulouse. The search for blood parasites was negative. The urine samples were centrifuged and then microscopically examined in the field. No blood-fluke eggs were found. The stool samples were mixed with a pre  相似文献   
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The nonelastolytic proteases trypsin and chymotrypsin were administered to hamsters 24 hours after intratracheal injection of elastase. Severity of the disease, extent of degradation and resynthesis, new cross-link formation, and the levels of the enzyme lysyl oxidase, which mediates the cross-link formation, were compared with the same parameters measured in hamsters with experimental emphysema induced by elastase alone. Increases in mean linear intercept indicated that a more severe form of the disease was produced. Although elastin degradation after 1 week was similar in both groups, resynthesis of the elastin destroyed by the elastolytic insult was significantly impaired in the animals injected sequentially with elastase and trypsin or chymotrypsin. Formation of new elastin as monitored by 14C-lysine incorporation into the elastin specific cross-links desmosine and isodesmosine was reduced approximately 40%, although there was no significant difference in the levels of lysyl oxidase activity. It is suggested that the most likely mechanism compatible with the recorded observations involves destruction of the microfibrillar component of the elastic fiber by trypsin or chymotrypsin, resulting in the absence of the requisite template for resynthesis of the pulmonary elastin.  相似文献   
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Background:

Undergraduate surgery is at an important crossroads. Many departments report significant difficulties delivering effective teaching. Our student feedback indicated a dated surgical curriculum lacking structure, quality and uniformity. We report on a new ”blended” approach employing a combination of professional DVDs, case based discussions, online material and traditional bedside teaching designed to provide structure, standardization, and equality of learning .

Methods:

Year 4 students who had undertaken the new course and year 5 students who had participated in the traditional teaching programme were compared. Students completed a 20 item questionnaire about their experiences of the surgical teaching programme.

Results:

One hundred and seventy-one year 4 (70%) and148 year 5 students (66%) responded. Domains relating to “Overall Satisfaction with the course”, “Approval of innovative teaching methods and interactivity” and “Satisfaction with the clarity of course information” showed improvements when comparing the new and old programmes. However bedside teaching was not rated as highly in the new programme (p<0.05).

Conclusion:

This blended approach has resulted in improved student understanding and engagement. The apparent compromise of bedside teaching may be a reflection of higher expectations. We believe that a similar blended approach has the potential to re-invigorate surgical teaching elsewhere.  相似文献   
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It has been shown that learning a new skill leads to structural changes in the brain. However, it is unclear whether it is the acquisition or continuous practicing of the skill that causes this effect and whether brain connectivity of patients with schizophrenia can benefit from such practice. We examined the effect of 6 months exercise on a stationary bicycle on the brain in patients with schizophrenia and healthy controls. Biking is an endemic skill in the Netherlands and thus offers an ideal situation to disentangle the effects of learning vs practice. The 33 participating patients with schizophrenia and 48 healthy individuals were assigned to either one of two conditions, ie, physical exercise or life-as-usual, balanced for diagnosis. Diffusion tensor imaging brain scans were made prior to and after intervention. We demonstrate that irrespective of diagnosis regular physical exercise of an overlearned skill, such as bicycling, significantly increases the integrity, especially of motor functioning related, white matter fiber tracts whereas life-as-usual leads to a decrease in fiber integrity. Our findings imply that exercise of an overlearned physical skill improves brain connectivity in patients and healthy individuals. This has important implications for understanding the effect of fitness programs on the brain in both healthy subjects and patients with schizophrenia. Moreover, the outcome may even apply to the nonphysical realm.Key words: physical exercise, schizophrenia, diffusion tensor imaging, connectivity, longitudinal, fractional anisotropy  相似文献   
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Rheumatic diseases are multisystem conditions that predominantly affect the musculoskeletal system, leading to soft tissue and articular damage. Historically, medical therapy was able to slow, but not prevent, erosion and joint destruction, resulting in the frequent need for orthopedic procedures to maintain function and minimize pain. However, the widespread use of disease-modifying anti-rheumatic drugs (DMARDs) and biologic therapy over the last twenty years has resulted in a dramatic decrease in the incidence of musculoskeletal damage and impairment among these patients. This review will discuss changing patterns of orthopedic surgery among patients with rheumatic diseases, focusing on rheumatoid arthritis and systemic lupus erythematosus.  相似文献   
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In 2014, the vast majority of published biomedical research is still hidden behind paywalls rather than open access. For more than a decade, similar restrictions over other digitally available content have engendered illegal activity. Music file sharing became rampant in the late 1990s as communities formed around new ways to share. The frequency and scale of cyber-attacks against commercial and government interests has increased dramatically. Massive troves of classified government documents have become public through the actions of a few. Yet we have not seen significant growth in the illegal sharing of peer-reviewed academic articles. Should we truly expect that biomedical publishing is somehow at less risk than other content-generating industries? What of the larger threat—a “Biblioleaks” event—a database breach and public leak of the substantial archives of biomedical literature? As the expectation that all research should be available to everyone becomes the norm for a younger generation of researchers and the broader community, the motivations for such a leak are likely to grow. We explore the feasibility and consequences of a Biblioleaks event for researchers, journals, publishers, and the broader communities of doctors and the patients they serve.  相似文献   
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IntroductionThe Royal College of Surgeons of England (RCS) has issued guidance regarding the use of reoperation rates in the revalidation of UK-based orthopaedic surgeons. Currently, little has been published concerning acceptable rates of reoperation following primary surgical management of orthopaedic trauma, particularly with reference to revalidation.MethodsA retrospective review was conducted of patients undergoing clearly defined reoperations following primary surgical management of trauma between 1 January 2010 and 31 December 2011. A full case note review was undertaken to establish the demographics, clinical course and context of reoperation. A review of the imaging was performed to establish whether the procedure performed was in line with accepted trauma practice and whether the technical execution was acceptable.ResultsA total of 3,688 patients underwent primary procedures within the time period studied while 70 (1.90%, 99% CI: 1.39–2.55) required an unplanned reoperation. Thirty-nine (56%) of these patients were male. The mean age of patients was 56 years (range: 18–98 years) and there was a median time to reoperation of 50 days (IQR: 13–154 days). Potentially avoidable reoperations occurred in 41 patients (58.6%, 99% CI: 43.2–72.6). This was largely due to technical errors (40 patients, 57.1%, 99% CI: 41.8–71.3), representing 1.11% (99% CI: 0.73–1.64) of the total trauma workload. Within RCS guidelines, 28-day reoperation rates for hip, wrist and ankle fractures were 1.4% (99% CI: 0.5–3.3), 3.5% (99% CI: 0.8%–12.1) and 1.86% (99% CI: 0.4–6.6) respectively.ConclusionsWe present novel work that has established baseline reoperation rates for index procedures required for revalidation of orthopaedic surgeons.  相似文献   
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