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排序方式: 共有1771条查询结果,搜索用时 15 毫秒
51.
Haim A. Abenhaim Nouf Alrowaily Nicholas Czuzoj-Shulman Andrea R. Spence Stephanie L. Klam 《The journal of maternal-fetal & neonatal medicine》2016,29(22):3596-3601
Objective: Pregnancies among morbidly obese women are associated with serious adverse maternal and neonatal outcomes. Our study objective is to evaluate the effect of bariatric surgery on obstetrical outcomes.Methods: We carried out a retrospective cohort study using the healthcare cost and utilization project – Nationwide Inpatient Sample from 2003 to 2011 comparing outcome of births among women who had undergone bariatric surgery with births among women with morbid obesity. Logistic regression was used to estimate the adjusted effect of bariatric surgery on maternal and newborn outcomes.Results: There were 8 475 831 births during the study period (221 580 (2.6%) in morbidly obese women and 9587 (0.1%) in women with bariatric surgery). Women with bariatric surgery were more likely to be Caucasian and ≥35 years old as compared with morbidly obese women. As compared with women with morbid obesity, women with bariatric surgery had lower rates of hypertensive disorders, premature rupture of membrane, chorioamnionitis, cesarean delivery, instrumental delivery, postpartum hemorrhage, and postpartum infection. Induction of labor, postpartum blood transfusions, venous thromboembolisms, and intrauterine fetal growth restriction were more common in the bariatric surgery group. There were no differences observed in preterm births, fetal deaths, or reported congenital anomalies.Conclusion: In general, women who undergo bariatric surgery have improved pregnancy outcomes as compared with morbidly obese women. However, the bariatric surgery group was more likely to have venous thromboembolisms, to require a blood transfusion, to have their labor induced and to experience fetal growth restriction. 相似文献
52.
The time for reproduction in mammals largely depends on the availability of water and food in their habitat. Therefore, in regions where rains are limited to definite seasons of the year, mammals presumably will restrict their breeding correspondingly. But while mammals living in predictable ecosystems would benefit by timing their season to an ultimate predictable cue, such as photoperiod, in unpredictable ecosystems (e.g., deserts) they will need to use a more proximate signal. We suggest a mechanism by which water shortage (low water content in plants) could act as a proximate cue for ending the reproductive season. The golden spiny mouse (Acomys russatus), a diurnal rodent living in extreme deserts, may face an increased dietary salt content as the summer progresses and the vegetation becomes dry. Under laboratory conditions, increased diet salinity lead to reproductive hiatus in females, notable in imperforated vagina, and a significant decrease in the ovaries, uteri, and body masses. In females treated with vasopressin (VP), a hormone expressed during water stress, the uteri and body masses have decreased significantly, and the ovaries exhibited an increased number of atretic follicles. VP has also led to a significant decrease in relative medullary thickness (RMT) of the kidney. It is thus suggested that VP could act as a modulator linking the reproductive system with water economy in desert rodents, possibly through its act on the energetic pathways. 相似文献
53.
A couple with unexplained infertility was referred for routine IVF and ICSI treatment. Ovulation was induced by the GnRH analogue protocol combined with HMG and HCG. Preparation of denuded oocytes revealed a major disorder of the zona pellucida and abnormal oocytes. During preparation of ova for ICSI, 15 retrieved oocytes were denuded, 14 of which underwent ICSI treatment. Four of the oocytes collapsed and the remaining 10 appeared to have irregular, fragile zona pellucida. Nevertheless, following ICSI, seven low-quality embryos developed, three of which were transferred into the uterus. Two implantations were achieved, but only one embryo resulted in an uneventful pregnancy and delivery by Caesarean section of a normal female neonate with an Apgar score of 10. It is hypothesized that infertility was due to the abnormal oocyte structure and abnormal zona pellucida, which prevented natural conception. This condition was successfully resolved by the ICSI procedure. 相似文献
54.
Levy H Weiss S Altboum Z Schlomovitz J Glinert I Sittner A Shafferman A Kobiler D 《Infection and immunity》2012,80(8):2623-2631
The virulence of Bacillus anthracis, the causative agent of anthrax, stems from its antiphagocytic capsule, encoded by pXO2, and the tripartite toxins encoded by pXO1. The accepted paradigm states that anthrax is both an invasive and toxinogenic disease and that the toxins play major roles in pathogenicity. We tested this assumption by a systematic study of mutants with combined deletions of the pag, lef, and cya genes, encoding protective antigen (PA), lethal factor (LF), and edema factor (EF), respectively. The resulting seven mutants (single, double, and triple) were evaluated following subcutaneous (s.c.) and intranasal (i.n.) inoculation in rabbits and guinea pigs. In the rabbit model, virulence is completely dependent on the presence of PA. Any mutant bearing a pag deletion behaved like a pXO1-cured mutant, exhibiting complete loss of virulence with attenuation indices of over 2,500,000 or 1,250 in the s.c. or i.n. route of infection, respectively. In marked contrast, in guinea pigs, deletion of pag or even of all three toxin components resulted in relatively moderate attenuation, whereas the pXO1-cured bacteria showed complete attenuation. The results indicate that a pXO1-encoded factor(s), other than the toxins, has a major contribution to the virulence mechanism of B. anthracis in the guinea pig model. These unexpected toxin-dependent and toxin-independent manifestations of pathogenicity in different animal models emphasize the importance and need for a comprehensive evaluation of B. anthracis virulence in general and in particular for the design of relevant next-generation anthrax vaccines. 相似文献
55.
Elad Goldberg Haim Ben Zvi Liron Sheena Summer Sofer Ilan Krause Ella H. Sklan Amir Shlomai 《Clinical microbiology and infection》2021,27(6):917.e1-917.e4
ObjectivesThe effectiveness of remdesivir, a Food and Drug Administration-approved drug for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has been repeatedly questioned during the current coronavirus disease 2019 (COVID-19) pandemic. Most of the recently reported studies were randomized controlled multicentre clinical trials. Our goal was to test the efficiency of remdesivir in reducing nasopharyngeal viral load and hospitalization length in a real-life setting in patients admitted to a large tertiary centre in Israel.MethodsA total of 142 COVID-19 patients found to have at least three reported SARS-CoV-2 quantitative RT-PCR tests during hospitalization were selected for this study. Of these, 29 patients received remdesivir, while the remaining non-treated 113 patients served as controls.ResultsAmong the tested parameters, the control and remdesivir groups differed significantly only in the intubation rates. Remdesivir treatment did not significantly affect nasopharyngeal viral load, as determined by comparing the differences between the first and last cycle threshold values of the SARS-CoV-2 quantitative RT-PCR tests performed during hospitalization (cycle threshold 7.07 ± 6.85 vs. 7.08 ± 7.27, p 0.977 in the control and treated groups, respectively). Remdesivir treatment shortened hospitalization length by less than a day compared with non-treated controls and by 3.1 days when non-intubated patients from both groups were compared. These differences, however, were not statistically significant, possibly because of the small size of the remdesivir group.DiscussionRemdesivir was not associated with nasopharyngeal viral load changes, but our study had a significant disease severity baseline imbalance and was not powered to detect viral load or clinical differences. 相似文献
56.
Plate osteosynthesis of the mandibular condyle 总被引:3,自引:0,他引:3
Günter Lauer Dominik Haim Peter Proff Gerd Richter Winnie Pradel Jochen Fanghnel Eckhard Pilling Tomasz Gedrange Ronald Mai 《Annals of anatomy》2007,189(4):412-417
The aim of this study is to evaluate and compare the biomechanical stability of various osteosynthesis materials for mandible condylar-process fractures. On 160 porcine mandibles, four different monocortical plating techniques (40 per group) were investigated. Condyles were fractured at a defined location from the incisure to the posterior border. After correct anatomical reduction the fractures were plated, using four different techniques. Osteosynthesis materials used were the delta plate, the trapezoid plate, the dynamic compression plate and double mini-plates. Each group was subjected to linear loading in lateral to medial, medial to lateral, anterior to posterior and posterior to anterior directions by a universal mechanical testing machine TIRAtest 2720. Yield load, yield displacement were measured for the different plates. Statistically significant differences were noted between the fixation groups in all four directions. Rigid internal fixation with double mini plates showed the best stability in all directions except posterior to anterior. In this direction, the delta-plate resisted the highest loads. In the three other directions, the delta plate was second best with data similar to double miniplates but lower in magnitude. 相似文献
57.
The reduction of artifacts due to metal hip implants in CT-attenuation corrected PET images from hybrid PET/CT scanners 总被引:1,自引:0,他引:1
Kennedy JA Israel O Frenkel A Bar-Shalom R Azhari H 《Medical & biological engineering & computing》2007,45(6):553-562
CT beam hardening artifacts near metal hip implants may erroneously enhance or diminish radiotracer uptake following CT attenuation correction (AC) of PET images. An artifact reduction algorithm (ARA) was developed to reduce metal artifacts in CT-based AC-PET. The algorithm employed a Bayes classifier to identify beam-hardening artifacts, followed by a partial correction of the attenuation map. ARA was implemented on phantom and patient 18F-FDG studies using a clinical PET/CT scanner. In phantom studies ARA successfully removed two artifacts of erroneously elevated uptake near a stainless steel hip prosthesis which were depicted in the standard CT-AC PET. ARA has also identified two targets absent on the scanner PET images. Target-to-background ratios were 1.5-3 times higher for ARA-PET than scanner images. In a patient study, metal artifacts were of lower intensity in ARA-PET as compared to standard images. Potentially, ARA may improve detectability of small lesions located near metal hip implants. 相似文献
58.
The spondylometaphyseal dysplasias are a very heterogeneous group of disorders. Only one has been clearly defined, namely, the spondylometaphyseal dysplasia — Kozlowski type, known also as the common type. This disorder is inherited as an autosomal dominant trait. In this report we describe an Arabic-Moslem kindred with spondylometaphyseal dysplasia, not of the common type, with an autosomal dominant mode of inheritance, indicating further heterogeneity. 相似文献
59.
Solid bony fusion of large joints affected with active chronic infections, is still the most effective surgical solution to establish a useful function of the affected limb. Even with extensive peri-articular bone loss and severe deformities, arthrodesis in a functional position can provide effective stability. The reported fusion rates in such patients are not encouraging however, and secondary amputations have been reported. Compression arthrodesis using an Ilizarov external fixation frame was performed for 17 destroyed feet (14 tibiotalar and 3 subtalar joints) and 6 badly disrupted knees in a series of 20 patients. Evaluation of the results was based on the clinical and radiological joint alignment, achievement of fusion, presence or absence of infection, and functional outcome. One patient after knee joint arthrodesis was lost to follow-up, and two knees had developed a clinically stable fibrous union. Solid fusion was obtained in all other joints. All joints were in anatomical alignment and the patients were fully functional at the time of review. Our experience of using the Ilizarov fixation frame for achieving joint fusion is very rewarding. The results reported hereby justify the further use of this hybrid frame as an effective mechanical method to achieve bony joint fusion without bone grafts, and to ensure a low failure rate. 相似文献
60.
Kennedy JA Israel O Frenkel A Bar-Shalom R Azhari H 《European journal of nuclear medicine and molecular imaging》2007,34(4):517-531
Purpose To improve the PET image quality of a hybrid PET/CT scanner by merging CT borders with PET texture. PET/CT scanners provide
both high-resolution CT images showing anatomical details and PET images of low-resolution physiological information about
radiopharmaceutical uptake. Standard smoothing of noisy PET images may further impair PET resolution, reducing small lesion
detectability.
Methods The CT edge data and the PET texture data were merged using a modified form of an algorithm called HCT (hybrid computed tomography).
In merged PET/CT images, each PET pixel value was estimated by iteratively applying a corrected 2D Taylor expansion to each
of its eight neighbors. The spatial derivative term was used only near anatomical edges provided by the CT. This counts-preserving
algorithm was tested on a special resolution phantom and patient data sets obtained by PET/CT acquisitions.
Results The HCT algorithm provided phantom PET images with sharp borders and improved resolution (≤3 mm as compared to ≥4 mm). HCT
increased the signal to background contrast ratios by an average of 61% (40–89%) while maintaining noise reduction similar
to the Gaussian filtering standard in PET. In the clinical PET images, HCT allowed for an improved delineation of pulmonary
and pelvic lesions and an improved visualization of the brain.
Conclusion A new reconstruction algorithm for merging CT anatomical edge data with functional PET data has been introduced. The algorithm
smoothes noisy PET images while retaining sharper edges at corresponding anatomical borders, resulting in an improvement in
resolution and contrast ratio. 相似文献