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101.
102.
Anthropogenic and nonanthropogenic (erosion) processes contribute to the continuing presence of asbestos and nonasbestos elongated mineral particles (EMP) of amphibole and serpentine in air and water of urban, rural, and remote environments. The anthropogenic processes include disturbance and deterioration of asbestos-containing materials, mining of amphibole- and serpentine-bearing rock, and disturbance of soils containing amphibole and serpentine. Atmospheric dispersal processes can transport EMP on a global scale. There are many methods of establishing the abundance of EMP in air and water. EMP include cleavage fragments, fibers, asbestos, and other asbestiform minerals, and the methods employed do not critically distinguish among them. The results of most of the protocols are expressed in the common unit of fibers per square centimeter; however, seven different definitions for the term “fiber” are employed and the results are not comparable. The phase-contrast optical method used for occupational monitoring cannot identify particles being measured, and none of the methods distinguish amphibole asbestos from other EMP of amphibole. Measured ambient concentrations of airborne EMP are low, and variance may be high, even for similar environments, yielding data of questionable value for risk assessment. Calculations based on the abundance of amphibole-bearing rock and estimates of asbestos in the conterminous United States suggest that amphibole may be found in 6–10% of the land area; nonanthropogenic erosional processes might produce on the order of 400,000 tons or more of amphibole per year, and approximately 50 g asbestos/km2/yr; and the order of magnitude of the likelihood of encountering rock bearing any type of asbestos is approximately 0.0001.  相似文献   
103.
104.
Patients with failure of infarct-related artery recanalization after thrombolytic therapy have a poor clinical outcome. These patients have been considered for rescue angioplasty 90 min after thrombolytic therapy at the time of emergency catheterization in the course of five Thrombolysis and Angioplasty in Myocardial Infarction (TAMI) trials. The outcome of 776 patients with patent infarct-related vessels after emergency catheterization was analyzed--607 with thrombolysis-mediated patency of the infarct-related vessel and 169 with patency achieved by angioplasty. Baseline characteristics of the thrombolysis and angioplasty patency groups were similar except for a higher acute left ventricular ejection fraction (51.3% versus 48.2%) in the thrombolysis group (p = 0.003). Seven to 10 day left ventricular ejection fraction was higher (52.3% versus 48.1%), infarct zone functional recovery was greater (0.44 versus 0.21 standard deviation/chord, or 18% versus 7%, p = 0.001) and reocclusion was less (11% versus 21%) in the thrombolysis compared with the angioplasty group. Despite these differences, angioplasty patency was associated with the same low in-hospital mortality rate (5.9% versus 4.6%) and long-term mortality rate (3% versus 2%) as thrombolysis patency. Reocclusion adversely affected the mortality rate and ventricular functional recovery. Technical failure of rescue angioplasty was associated with a much higher mortality rate than was technical success (39.1% versus 5.9%). Thrombolysis patency was preferable to angioplasty patency after thrombolytic therapy in acute myocardial infarction, but both were associated with the same low in-hospital and long-term mortality rates, suggesting that rescue angioplasty is beneficial in some patients with failure of infarct-related artery recanalization after thrombolytic therapy.  相似文献   
105.
ABSTRACT

Objectives: Whole blood-derived platelet concentrates can be obtained by the platelet-rich plasma (PRP-PCs) or the buffy-coat (BC-PCs) method. Few studies have shown that BC-PCs display lower in vitro platelet activation, but scarce information exists regarding transfusion efficacy. We have performed a retrospective study assessing platelet transfusion in patients undergoing allogeneic hematopoietic cell transplantation (AHCT) in our clinic, before and after the implementation of BC-PCs.

Methods: We reviewed clinical records corresponding to 70 PRP-PCs and 86 BC-PCs prophylactic transfusions, which were performed to 55 AHCT patients. Transfusion efficacy was assessed by the 24-h post-transfusion corrected count increment (24-h CCI) and bleeding events. Clinical factors affecting transfusion outcome were also investigated.

Results: Clinical characteristics and the total number of platelet transfusions were similar among groups. Mean donor exposure was 5.8 and 5.0 in each single PRP-PCs and BC-PCs transfusion, respectively (p?<?0.01). The 24-h CCI was significantly higher in patients transfused with BC-PCs than in those receiving PRP-PCs (8.3[2.7–13.4] vs. 4.7[1.3–8.1]; p?<?0.01). Independent predictors of poor platelet transfusion response included diagnosis other than acute leukemia (HR 8.30; 95% CI 1.96–35.22; p?=?0.004), splenomegaly (HR 8.75; 95% CI 2.77–27.60; p?<?0.001), graft versus host disease prophylaxis different from cyclosporine A and methotrexate (HR 3.96; 95% CI 1.55–10.14; p?=?0.004) and PRP-PCs transfusion (HR 4.54; 95% CI 1.72–12.01; p?=?0.002). There were no differences between both groups regarding the bleeding events.

Conclusion: In the AHCT setting, we hypothesize that BC-PCs transfusion, when compared to PRP-PCs, results in higher CCI and reduced donor exposure, but provides no significant benefit regarding bleeding outcome.  相似文献   
106.
AIM: Although mucosectomy according to Longo was a real revolution in the treatment of haemorrhoidal disease, Milligan-Morgan haemorrhoidectomy, maintaining the characteristics of a technique which is physiopathologically efficacious and easily performed, is still the procedure of choice in some clinical conditions. The aim of this study was to evaluate which of the two techniques, Milligan-Morgan haemorrhoidectomy and Longo mucoprolapsectomy, could be considered the gold standard in the treatment of haemorrhoidal disease. METHODS: From March 2002 to October 2006, in the VII Department of General Surgery of SUN, we compared two groups of 26 patients each: one treated with Milligan-Morgan haemorrhoidectomy, the other one with Longo mucoprolapsectomy. Among the patients treated with traditional technique, 16 were suffering from grade III haemorrhoids and prolapse, while the other 10 from grade IV haemorrhoids and prolapse. The group treated with stapler was composed of 10 patients affected by grade III haemorrhoids and prolapse, while the other 16 were patients complaining for grade IV haemorrhoids and prolapse. For both groups of patients the follow-up lasted 12 months; they were controlled at 1 week, 1 month, 6 months and 1 year after the operation. RESULTS: The level of pain measured with a visual analogue scale (VAS) was always higher in the group treated with traditional technique. In 69% of the patients treated with stapler and in 59% of those treated with open technique there was the first defecation within postoperative day 2. The return to normal activity was earlier in patients who underwent Longo technique. Among the patients treated with traditional technique, 7.7% had postoperative bleeding, 15.4% at the 6-month control, suffered from anal fissure with associated high pressure of anal sphincter and tenesmus and 7.7% showed a recurrence after 1 year. In the group treated with Longo technique, 11.54% of the patients had a postoperative haemorrhage at the 6-month control, 7.7% showed substenosis, 3.84% of the patients felt tenesmus; in 3.84% of the cases a perianal extra-sphincteric fistula was evident. At 1 year control, 11.54% of the patients showed recurrences. CONCLUSION: The conclusion is drawn that it does not exist any indication for the Longo technique; however, it seems to give the best results in grade III haemorrhoids with prolapse, without sphincteric implications.  相似文献   
107.
Nurse educators often lament there is not enough time to teach all the content students need to learn. Every year, information regarding healthcare increases exponentially. Typically, educators respond by increasing content without removing outdated information resulting in overcrowded courses. Little time is left for meaningful learning of concepts and life-long learning skills to sustain graduates throughout their careers. Reliance on conventional teacher-centered approaches to curriculum development have generated calls from professional organizations for innovative education programs. Innovation begins by shifting focus from massive amounts of content to teaching essential concepts and abilities necessary for today's health care environment. Decreasing the overload of content is imperative when moving from a teaching centered to a learning-centered curricula. Instead of concentrating on rote memorization, students engage in meaningful learning. De-crowding the curriculum can be frustrating because there is no quick fix. The challenge is to consider both faculty philosophical beliefs and assumptions about how students learn. Assumptions and beliefs regarding teaching, learning, essential content, and the learning environment should be clear from the outset. Without considering assumptions and beliefs efforts to de-crowd the curriculum rapidly devolve into a test of wills between faculty members. The authors present an overview of learning-centered education, a systematic method for de-crowding the curriculum, and a discussion of challenges encountered.  相似文献   
108.
The authors report on a case of fibro-leiomyoma of the upper oesophagus. The patient presented dysphagia and oppressive retrosternal pain. Computed tomography and magnetic resonance of the thorax revealed a solid voluminous formation at the level of the posterior upper mediastinum. The US-endoscopy showed that this was a tumour originating from the esophageal wall with macroscopic characteristics of benignity, suggestive of a leiomyoma. The patient was treated by thoracotomy enucleation of the large tumour after sectioning the azygous vein on the same side as the lesion. Histological examination of the surgical resection confirmed that the tumour was a fibro-leiomyoma of the esophagus with a conspicuous vascular component and an interstitial inflammatory focus. The patient now appears to be asymptomatic and illness-free.  相似文献   
109.
Leptospirosis is a zoonosis that affects humans, domestic animals, and wildlife. Carnivores are at the top of the feeding chain, thus being exposed to pathogens through their preys. From June 2004 to April 2007, we analyzed for evidences of contact with 14 serovars of Leptospira interrogans Sensu Lato serum (analyzed by indirect Microscopic Agglutination Test) and urine or kidney samples (analyzed by microscopic observation, immunostaining and culture) collected from 201 wild and domestic carnivores, including 26 free-living Iberian lynx (Lynx pardinus), 33 red foxes (Vulpes vulpes), 33 Egyptian mongooses (Herpestes ichneumon), 25 common genets (Genetta genetta), two Eurasian badgers (Meles meles) and one Eurasian otter (Lutra lutra), and 53 free-roaming cats and 28 rural dogs in protected areas in Andalusia (southern Spain). Twenty-three percent of the animals presented evidences of contact, being the prevalence similar among wild (23.5%) and domestic species (22.2%). Contact with Lesptospira was detected in all the species but the otter. Prevalence was: lynx (11% by bacteriological detection, 32% by serology), fox (0%, 47%), mongoose (5%, 20%), genet (0%, 12%), badger (0%, 50%), cat (20%, 14%), dog (only serology: 36%). Serovar Icterohemorragiae accounted for 2/3 of the cases. Serovar Canicola was detected in half of the positive dogs and one lynx. Other serovars detected were Ballum, Sejro?, and Australis. No macroscopic lesions were observed in necropsied animals that showed evidence of contact with the agent, although histopathologic lesions (chiefly chronic interstitial nephritis) were observed in 7 out of the 11 microscopically analyzed individuals. Thus, L. interrogans may cause previously unrecorded disease in wild carnivores in Spain. Wild and free-roaming carnivores may not act as reservoir of L. interrogans but as a dead-end hosts, though the dog may act as reservoir of serovar Canicola. Carnivores are apparently good sentinels for the epidemiological monitorization of leptospirosis.  相似文献   
110.
PURPOSE: This study was undertaken to assess the diagnostic accuracy of high-resolution ultrasonography (HRUS) in the detection of meniscal cysts. MATERIALS AND METHODS: Over a 2-year period, 1,857 patients underwent magnetic resonance imaging (MRI) of the knee for traumatic or degenerative disorders. All patients with MRI evidence of a meniscal cyst were studied by HRUS. HRUS was also performed on an equal number of patients without MRI evidence of meniscal cyst who were used as a control group. All HRUS examinations were conducted by a radiologist blinded to the MRI findings. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of HRUS were assessed with reference to MRI. All patients underwent surgery, and the resected masses were studied by histological examination. RESULTS: MRI allowed identification of a meniscal cyst in 52 patients. HRUS enabled correct detection of the meniscal cyst in 49/52 cases. In the control group, HRUS excluded the presence of meniscal cysts in all cases. HRUS had a sensitivity, specificity, PPV and NPV of 94.23%, 100%, 100% and 94.54%, respectively, for the detection of meniscal cysts. CONCLUSIONS: HRUS is a fairly reliable technique in the detection, characterisation and differentiation of the different forms of meniscal cyst.  相似文献   
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