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931.
ObjectivesTo investigate the effects of prior treatment and determine the predictors of a 12-month treatment response of romosozumab (ROMO) in 148 patients with postmenopausal osteoporosis.MethodsIn this prospective, observational, and multicenter study, treatment naïve patients (Naïve; n = 50) or patients previously treated with bisphosphonates (BP; n = 37) or denosumab (DMAb; n = 45) or teriparatide (TPTD; n = 16) (mean age, 75.0 years; T-scores of the lumbar spine [LS] ?3.2 and total hip [TH] ?2.6) were switched to ROMO due to insufficient effects of prior treatment. Bone mineral density (BMD) and serum bone turnover markers were evaluated for 12 months.ResultsAt 12 months, changes in LS BMD were Naïve (18.2%), BP (10.2%), DMAb (6.4%), and TPTD (11.2%) (P < 0.001 between groups) and changes in TH BMD were Naïve (5.6%), BP (3.3%), DMAb (0.6%), and TPTD (4.4%) (P < 0.01 between groups), respectively. In all groups, the LS BMD significantly increased from baseline at 6 and 12 months, although only the DMAb group failed to obtain a significant increase in TH BMD during 12-month treatment. Mean values of N-terminal type I procollagen propeptide (PINP; μg/L) from baseline → 1 month → 12 months were Naïve (67.9 → 134.1 → 51.0), BP (32. 2 → 81.7 → 40.9), DMAb (30.4 → 56.2 → 75.3), and TPTD (97.4 → 105.1 → 37.1), and those of isoform 5b of tartrate-resistant acid phosphatase (TRACP-5b; mU/dL) were Naïve (500.4 → 283.8 → 267.1), BP (273.4 → 203.1 → 242.0), DMAb (220.3 → 246.1 → 304.8), and TPTD (446.6 → 305.1 → 235.7), respectively. Multiple regression analysis revealed that the significant predictors of BMD change at 12 months were difference of prior treatment (r = ?2.8, P < 0.001) and value of PINP at 1 month (r = 0.04, P < 0.01) for LS, and difference of prior treatment (r = ?1.3, P < 0.05) and percentage change of TRACP-5b at 1 month (r = ?0.06, P < 0.05) for TH.ConclusionsThe early effects of ROMO on LS and TH BMD increase at 12 months were significantly affected by the difference of prior treatment and are predicted by the early change in bone turnover markers.  相似文献   
932.
933.
BackgroundHolmium laser enucleation of the prostate (HoLEP) has been a widely utilized minimally invasive surgical procedure for benign prostate hyperplasia. The current study aimed to compare surgical outcomes and King’s Health Questionnaire (KHQ) assessment scores following HoLEP between younger men and those aged ≥75 years.MethodsThis prospective single-center study compared perioperative complications, postoperative urinary conditions, and KHQ scores (nine categories) between men aged ≥75 years (group A) and men aged <75 years (group B) before and 1, 3, and 6 months after surgery.ResultsA total of 100 patients were included for analysis (group A, n=38 and group B, n=62). No differences in patient backgrounds, perioperative complications, such as perioperative decrease in hemoglobin, postoperative fever, postoperative indwelling catheterization duration, or postoperative hospitalization duration, and KHQ were observed between both groups. Both groups showed significantly better International Prostate Symptom Scores, quality of life, maximum urinary flow rate, and postvoid residual volume 1, 3, and 6 months after HoLEP compared to their respective preoperative levels (P<0.01). Regarding KHQ categories, both groups showed significantly better general health perceptions, impact on life, emotions, and sleep/energy 1 month after HoLEP; role limitations, physical limitations, and social limitations 3 months after HoLEP; and personal relationships and incontinence severity measures 6 months after HoLEP compared to their respective preoperative levels (P<0.05).ConclusionsHoLEP could be safe and effective even for men aged ≥75 years, comparing complications, urinary condition, and KHQ scores.  相似文献   
934.
935.
936.
Sorex araneus and Sorex granarius are sibling species within the Sorex araneus group with karyotypes composed of almost identical chromosome arms. S. granarius has a largely acrocentric karyotype, while, in S. araneus, various of these acrocentrics have combined together by Robertsonian (Rb) fusions to form metacentrics, with the numbers and types of metacentrics differing between chromosomal races. Our studies on telomeric sequences in S. araneus and S. granarius revealed differences between chromosomes and between species. In S. araneus (the Novosibirsk race), hybridization signals were present on the telomeres of all the chromosomes after FISH with a PCR-generated telomeric probe. In addition, hybridization signals were observed at high frequencies in the pericentric regions of some but not all metacentrics formed by Rb fusion. There were fewer signals on those metacentrics formed earlier in the evolution of S. araneus. This suggests that S. araneus chromosomes retain at least some telomeric repeats during Rb fusion, but that these repeats are lost or modified over time. These results are critical for the interpretation of the well-studied hybrid zones between chromosomal races of S. araneus, given that Rb fission has been postulated in such hybrid zones and that the likelihood of Rb fission will relate to presence/absence of telomeric sequences at the centromeres of metacentrics. In S. granarius, there were strong signals at the proximal (centromeric) telomeres of the acrocentrics after FISH with a DNA telomeric probe. FISH with a PNA telomeric probe on S. granarius acrocentrics showed that the proximal telomeres were 213 kb on average, while the length of the distal telomeres was 3.8 kb on average. Two-colour FISH, using a telomeric DNA probe and a microdissected probe generated from the pericentric regions of the S. granarius chromosomes a and b, revealed regions on distinct chromatin fibres where telomeric and microdissected probes were colocalized or localized sequentially. The proximal telomeres of S. granarius are highly unusual both in their large size and their heterogeneous structure relative to the telomeres of other mammals.  相似文献   
937.
In many organisms completion of the first meiotic cell division depends on the correct assembly and disassembly of the synaptonemal complex (SC). This is a structure discovered a little over 50 years ago, which is formed by the close association of axes of homologous sister chromatid pairs. Its structure varies between organisms, although it retains a common tripartite organization in species as evolutionarily distant as budding yeast and humans. In mammals it is essential for crossover formation and completion of meiosis. Components of the mammalian SC have been identified only in the last 15 years, and mouse genetic approaches have started revealing the importance for this structure only in the past 5 years. Here we discuss the progress that has been made in the field of the mammalian SC and what approaches could be considered for its further study.  相似文献   
938.
We present a modeling framework designed for patient-specific computational hemodynamics to be performed in the context of large-scale studies. The framework takes advantage of the integration of image processing, geometric analysis and mesh generation techniques, with an accent on full automation and high-level interaction. Image segmentation is performed using implicit deformable models taking advantage of a novel approach for selective initialization of vascular branches, as well as of a strategy for the segmentation of small vessels. A robust definition of centerlines provides objective geometric criteria for the automation of surface editing and mesh generation. The framework is available as part of an open-source effort, the Vascular Modeling Toolkit, a first step towards the sharing of tools and data which will be necessary for computational hemodynamics to play a role in evidence-based medicine.  相似文献   
939.
Embryo transfer (ET) is the last stage of extracorporal fertilization during which the embryo is placed in the uterine cavity with a medium-filled catheter 2–3 days after in vitro fertilization. While fertilization in the laboratory occurs at very high rates (>:90%), the overall success of the procedure (i.e., take home baby) is still very low (<25%) and assumed to be mainly due to implantation failure. A computational model was developed to simulate ET within the uterine cavity by a fluid-filled catheter inserted into a two-dimensional channel with oscillating walls. The results showed that the speed at which the embryos are injected from the catheter dominates the procedure and controls the velocity of their transport within the uterine cavity. ET at excessively high injection speeds may lead to ectopic pregnancies, while uterine peristalsis affects transverse dispersion only during injection at low injection speeds. The presence of the catheter within the uterus does not affect flow patterns downstream of its tip. The potential risks to implantation failure due to mechanical factors involved in the ET processes are discussed. © 2003 Biomedical Engineering Society. PAC2003: 8719-j, 8710+e  相似文献   
940.
Materials are distributed throughout the body of mammals by fractal networks of branching tubes. Based on the scaling laws of the fractal structure, the vascular tree is reduced to an equivalent one-dimensional, tube model. A dispersion–convection partial differential equation with constant coefficients describes the heterogeneous concentration profile of an intravascular tracer in the vascular tree. A simple model for the mammalian circulatory system is built in entirely physiological terms consisting of a ring shaped, one-dimensional tube which corresponds to the arterial, venular, and pulmonary trees, successively. The model incorporates the blood flow heterogeneity of the mammalian circulatory system. Model predictions are fitted to published concentration-time data of indocyanine green injected in humans and dogs. Close agreement was found with parameter values within the expected physiological range. © 2003 Biomedical Engineering Society. PAC2003: 8710+e, 8719Hh, 8719Uv  相似文献   
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