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Pharmaceutical Research - Fluid-bed coating processes make it possible to manufacture pharmaceutical products with tuneable properties. The choice of polymer type and coating thickness provides...  相似文献   
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Background contextSpondylodesis in the operative management of lumbar spine diseases has been the subject of numerous studies over several decades. The posterolateral fusion (PLF) with pedicle screw fixation is a commonly used procedure.PurposeTo determine whether the addition of bone marrow concentrate (BMC) to allograft bone increases fusion rate after instrumented posterior lumbar fusion.Study designThe study was prospective, randomized, controlled, and blinded.MethodsEighty patients with degenerative disease of the lumbar spine underwent instrumented lumbar or lumbosacral PLF (22 men, 58 women; body mass index less than 35 for a good visualization of the PLF in the X-rays). In 40 cases, the PLF was done with spongious allograft chips alone (Group I, age 62.7 years in average, range 47–77 years, level of fusion 1–2). In another 40 cases, spongious allograft chips were mixed with BMC (Group II, age 58.5 years in average, range 42–80, level of fusion 1–3), including the mesenchymal stem cells (MSCs). Patients were scheduled for anteroposterior and lateral radiographs 12 and 24 months after the surgery and for computed tomography scanning 24 months after the surgery. Fusion status and the degree of mineralization of the fusion mass were evaluated separately by two radiologists blinded to patient group affiliation. The bony mass was judged as fused if there was uninterrupted bridging of well-mineralized bone between the transverse processes or sacrum, with trabeculation indicating bone maturation on least at one side of the spines.ResultsIn Group I at 12 months, the bone graft mass was assessed in X-rays as fused in no cases (0%) and at 24 months in four cases (10%). In Group II, 6 cases (15%) achieved fusion at 12 months and 14 cases (35%) at 24 months. The statistically significant difference between both groups was proven for complete fusion at both 12 (p=.041) and 24 months (p=.011). Computed tomography scans showed that 16 cases (40%) in Group I and 32 cases (80%) in Group II had evidence of at least unilateral continuous bridging bone between neighboring vertebrae at 24 months (p<.05).ConclusionsWe have confirmed the hypothesis that the autologous BMC together with the allograft is a better alternative for PLF than the allograft alone. The use of autologous MSCs in form of BMC in combination with allograft is an effective option to enhance the PLF healing.  相似文献   
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The study examined differences in Greek and Greek‐American diets and disease patterns related to migration within the Mediterranean and from the Mediterranean to the United States. Data reported here discuss changes in food patterns and health‐related characteristics of two populations, both originating from the Greek island of Chios, residing either in Athens, Greece, or urban centers in the United States. Food consumption and medical history questionnaires were mailed to 2652 Chians residing in Athens, New York, and the San Francisco Bay region of California. A total of 381 usable responses were obtained; 79% of both the Chian Greek and the Chian Greek American sample were first generation emigrants. Food consumption data were analyzed as monthly frequencies of 49 food items and categories using factor analysis and discriminate analysis. Associations between location of residence and disease prevalence were examined using maximum‐likelihood logit analysis; results were controlled for age, Body Mass Index, physical activity, smoking habit, and socio‐economic status. After controlling for these potential confounders, as well as for presence of the conditions of elevated serum cholesterol, hypertension, and diabetes, Chian American men were identified at higher risk for cardiovascular disease (CVD) than their Athenian counterparts (p < 0.06). This difference in risk for CVD may be related to more frequent use of oils and fats other than olive oil, and less frequent use of olive oil. Among women, diabetes exhibited a positive association with Chian women residing in Athens (p < 0.09), which may be explained by a less frequent use of foods rich in complex carbohydrates by Athenian women than by their American counterparts.  相似文献   
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We studied the diversity of the photosynthetic microscopic epilithon overgrowing the concrete walls of a cooling tower of the power plant at Be?chatów, central Poland. Epilithon samples were collected from the open upper part of concrete walls of a cooling tower in March 2006 and examined in labs as dried material in September 2006, and again in March 2011. The aerophytic assemblages were strongly dominated by a nostocalean cyanobacterium, Scytonema myochrous C. Agardh ex Bornet et Flahault. Other cyanobacteria and algae occurred very sporadically and in low abundance. The trichome morphology of S. myochrous growing directly on the tower differs considerably from that of lab-cultured ones. Trichomes from field material were very long, conspicuously sheathed and dark brown, with relatively sparse ramification and with cylindrical cells and heterocytes. Trichomes cultivated in the laboratory were shorter and thicker, with thin, hyaline sheaths which were not layered; they were frequently ramified, and the cells and heterocytes were discoid. Besides Scytonema myochrous, the first revitalized cyanobacteria growing in laboratory conditions included Nostoc sp., Leptolyngbya gracillima (Zopf ex Hansgirg) Anagnostidis et Komárek, and Gloeothece rupestris (Lyngbye) Bornet in Witrock et Nordstedt.  相似文献   
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A new nematode species, Philometra genypteri sp. n. (Philometridae), is described from male and female specimens found in the ovary of red cusk-eel, Genypterus chilensis (Guichenot) (Ophidiidae, Ophidiiformes), from the eastern South Pacific Ocean off the coast of northern Chile. Based on light and scanning electron microscopy examination, the new species differs from most other gonad-infecting Philometra spp. in the length of spicules (126–135 μm), a gubernaculum with dorsal lamella-like structures on its distal end, and the number and arrangement of genital papillae in the male. From a few congeneric, gonad-infecting species with unknown males, it can be distinguished by some morphological and biometrical features found in gravid female (absence of caudal projections, length of first-stage larvae or oesophagus, moderately developed anterior oesophageal inflation) and by the host type (fish family) and geographical distribution. P. genypteri is the first philometrid species reported from a fish belonging to the order Ophidiiformes and the second nominal species of Philometra recorded from marine fishes of the eastern South Pacific.  相似文献   
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Our previous studies revealed a considerably high level of chromosomal polymorphism in wild silkmoths, Samia cynthia ssp. (Lepidoptera: Saturniidae). Geographical populations of this species complex differ in chromosome numbers and show derived sex chromosome systems including Z0/ZZ in S. cynthia ricini (2n?=?27/28; Vietnam), neo-Wneo-Z/neo-Zneo-Z in S. cynthia walkeri (2n?=?26/26; Sapporo, Hokkaido) and neo-WZ1Z2/Z1Z1Z2Z2 in S. cynthia subsp. indet. (2n?=?25/26; Nagano, Honshu). In this study, we collected specimens of S. cynthia pryeri in Japanese islands Kyushu, Shikoku and Honshu, with an ancestral-like karyotype of 2n?=?28 in both sexes and a WZ/ZZ sex chromosome system, except for one population, in which females have lost the W chromosome. However, the S. cynthia pryeri W chromosome showed a very unusual morphology: It was composed of a highly heterochromatic body, which remained condensed throughout the whole cell cycle and of a euchromatin-like “tail.” We examined molecular composition of the W and neo-W chromosomes in S. cynthia subspecies by comparative genomic hybridisation and fluorescence in situ hybridisation with W chromosome painting probes prepared from laser-microdissected W chromatin of S. cynthia pryeri. These methods revealed that the molecular composition of highly heterochromatic part of the S. cynthia pryeri W chromosome is very different and lacks homology in the genomes of other subspecies, whereas the euchromatin-like part of the W chromosome corresponds to a heterochromatic part of the neo-W chromosomes in S. cynthia walkeri and S. cynthia subsp. indet. Our findings suggest that the curious WZ system of S. cynthia pryeri may represent an ancestral state of the Samia species complex but do not exclude an alternative hypothesis of its derived origin.  相似文献   
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BackgroundThe purpose of this study was to evaluate the influence of both bundles of the anterior cruciate ligament (ACL) on knee stability, anterior–posterior translation (APT) and internal (IR) and external (ER) rotation in cadaveric knees using a computer navigation system.MethodsThe APT, IR, and ER of the knees were recorded in the intact condition, the anterolateral bundle (AM) or the posterolateral bundle (PL) deficit condition and in the ACL-deficient condition. The KT-1000 arthrometer was used for APT evaluation. The measurement of rotational movements was done using a rollimeter. All tests were performed at 30°, 60° and 90° of flexion.ResultsAt 30° of flexion: In the intact knee APT was 5.8 mm, IR 12.1°, ER 10.1°. After the AM was cut, the APT increased to 9.1 mm, IR to 13.9° and ER to 12.6°. After the PL was cut, the APT was 6.4 mm, IR 13.1° and ER 10.6°. After the AM and PL were cut, the APT was 10.8 mm, IR 15.7° and the ER was 12.9° on average.ConclusionsThe AM has a greater impact on the APT than the PL in all knee joint flexion angles. The PL does not resist the rotational stability more than the AM. The rotational stability is better controlled by both bundles of ACL as compared to one bundle of the ACL.Clinical RelevanceThis study acknowledges the fact that the both bundles of the ACL are importants for AP and rotational stability of the knee joint.  相似文献   
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The numerical simulation of the Korotkoff sounds is realized by a 14 segment hemodynamic model of the cardiovascular system developed in the Institute of Thermomechanics, Czech Academy of Sciences. The cardiovascular system is modeled by four segments of the pulsating heart and by 10 vascular segments of pulmonary and systemic circuits connected with the heart in series. To better understand the generation of Korotkoff sounds the systemic arterial flow is studied in detail by a distributed parameter model. The analysis of self-excited oscillations in a collapsible tube (i.e., the systemic artery) is based on a one-dimensional model where the effect of expected flow separation is replaced by the change of viscous friction along the tube.  相似文献   
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