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61.
Transthoracic parametric Doppler (TPD), unlike conventional ultrasonography, measures signals originating from movements of pulmonary blood vessel walls. In this pilot study, we tested TPD in 15 patients diagnosed with pulmonary embolism on computed tomography pulmonary angiography. Results were mapped to the upper, middle, and lower thirds of the right lung. In the lower third, TPD yielded 100% specificity and positive predictive value for acute pulmonary embolism. If validated in a larger series, this rapid bedside technique might obviate the need for computed tomography in specific cases. This could be advantageous in patients who are unstable, in intensive care, or have allergies to iodinated contrast material.  相似文献   
62.
Endometriosis is associated with an increased risk of ovarian cancer. Few studies have also shown increased risk of breast cancer. BRCA1/2 mutations are linked to an increased risk of breast and ovarian cancers but their relation to endometriosis is unknown.  相似文献   
63.
Hemophagocytic lymphohistiocytosis (HLH) is characterized by uncontrolled immune activation and is traditionally associated with inherited gene defects or acquired causes. In addition to abnormalities in cytotoxic granules and lysosomes, various primary immune deficiency disorders (PID) have been identified among patients suffering from HLH. Our purpose was twofold: to better characterize and detail the association between PID and HLH.  相似文献   
64.
Gender-specific differences in the prevalence, incidence, comorbidities, prognosis, severity, risk factors, drug-related aspects and outcomes of various medical conditions are well documented. We present a literature review on the extent to which research in this field has developed over the years, and reveal gaps in gender-sensitive awareness between the clinical portrayal and the translation into gender-specific treatment regimens, guidelines and into gender-oriented preventive strategies and health policies. Subsequently, through the lens of gender, we describe these domains in detail for four selected medical conditions: Asthma, obesity and overweight, chronic kidney disease and coronavirus disease 2019. As some of the key gender differences become more apparent during adolescence, we focus on this developmental stage. Finally, we propose a model which is based on three influential issues: (1) Investigating gender-specific medical profiles of related health conditions, rather than a single disease; (2) The dynamics of gender disparities across developmental stages; and (3) An integrative approach which takes into account additional risk factors (ethnicity, socio-demographic variables, minorities, lifestyle habits etc.). Increasing the awareness of gender-specific medicine in daily practice and in tailored guidelines, already among adolescents, may reduce inequities, facilitate the prediction of future trends and properly address the characteristics and needs of certain subpopulations within each gender.  相似文献   
65.
66.
OBJECTIVES: To determine the safety of pedicle screw fixation in thoracic spine deformity correction. METHODS: One hundred twelve pedicle screws were surgically placed in 25 patients with degenerative, posttraumatic, and Scheuermann kyphosis and idiopathic and neuromuscular scoliosis. Screw position was evaluated using intraoperative and postoperative radiographs and thin-slice computed tomography. RESULTS: Of the total 112 thoracic pedicle screws that were inserted, 98 screws (87.5%) were fully contained within the cortical boundaries of the pedicle. When comparing proximal screws (T1-T8) with distal screws (T9-T12) and convex placed screws with concave ones, a statistically significant difference in screw placement was evident (P < 0.05). More misplaced screws were seen proximally and on the concave side. Of the 14 malpositioned screws, 2 (1.8%) demonstrated aortic abutment. There were no neurologic deficits, vascular injuries, or mechanical failures recorded. CONCLUSIONS: Placement of thoracic pedicle screws is both feasible and safe.  相似文献   
67.
The association between clinical coronary artery disease, cerebrovascular disease, and aortic atherosclerosis has not been examined in the general population. Transesophageal echocardiography was performed in 581 subjects, a random sample of the Olmsted County (Minnesota) population aged >/=45 years, participating in the Stroke Prevention: Assessment of Risk in a Community (SPARC) study. The frequency and severity of atherosclerosis of the thoracic aorta were determined in the population and the association between clinical coronary artery disease, cerebrovascular disease, and aortic atherosclerosis was examined. Previous myocardial infarction, angina pectoris, and coronary artery bypass surgery were significantly associated with aortic atherosclerosis, adjusting for age and gender (p 4-mm thick, ulcerated plaques, or mobile debris), adjusting for age and gender (p <0.05). Age, smoking, pulse pressure, previous myocardial infarction (odds ratio [OR] 4.67; 95% confidence interval [CI] 1.42 to 15.40), and coronary artery bypass surgery (OR 5.12; 95% CI 1.01 to 26.01) were independently associated with aortic atherosclerosis. Among subjects with atherosclerosis, age, smoking, pulse pressure, hypertension treatment, and coronary artery disease (OR 2.50; 95% CI 1.18 to 5.30) were independently associated with complex atherosclerosis. Weak associations were observed between previous ischemic stroke, transient ischemic attack, and aortic atherosclerosis, associations that were not significant after age- and gender-adjustment (p >0.2). Thus, coronary artery disease is strongly associated with aortic atherosclerosis and complex atherosclerosis in the general population. Cerebrovascular disease is weakly associated with aortic atherosclerosis, thereby questioning the overall importance of aortic atherosclerosis in the pathogenesis of cerebrovascular events in the general population.  相似文献   
68.
Wound dressings aim to restore the milieu required for skin regeneration by protecting the wound from environmental threats, including penetration of bacteria, and by maintaining a moist healing environment. A wide variety of wound dressing products targeting various types of wounds and different aspects of the wound healing process are currently available on the market. Ideally, a dressing should be easy to apply and remove, and its design should meet both physical and mechanical requirements; namely water absorbance and transmission rate, handleability and strength. In this article, our novel biodegradable antibiotic-eluting wound dressings are described and the engineering aspects in the design are emphasized. These unique new wound dressings are based on a polyglyconate mesh, coated with a porous Poly(dl-lactic-co-glycolic acid) matrix. They demonstrated excellent mechanical and physical properties and desired release profiles of antibiotic drugs which enable bacterial inhibition. Hence, a new generation of wound dressings is now emerging with clear benefits. These include better protection against infection and reducing the need for frequent dressing changing.  相似文献   
69.
Ligand binding to B-cell receptors (BcRs) on the B-cell surface induces crosslinking and phosphorylation of BCRs by the Src family kinases, followed by initiation of signaling. Although the nature of the earliest events following receptor engagement is currently under intensive investigation, the precise connection between crosslinking and the signaling cascade triggering has thus far remained unclear.Using a novel multiscale, agent-based simulation of B-cell surface dynamics, we present a coherent quantitative analysis of the initial stages of B-cell activation following ligand presentation. The simulation reproduces experimental results of H3 uptake, immunoglobulin secretion, immunoelectron photomicrography and FRET. While merging multiple experimental techniques, the simulation captures all essential events in the first twenty seconds following ligand presentation, and is used to make predictions on subsequent molecular events. We show that B-cell activation is mediated through a positive feedback loop between Lyn and ITAM phosphorylation, but that specificity is achieved through a combination of BcR spatial segregation and BcR selective partitioning within lipid rafts following clustering.  相似文献   
70.
Fifty four women with repeated unsuccessful in vitro fertilization (IVF) cycles due to inadequate ovarian response to stimulation with human menopausal gonadotropins (hMG) participated in this study. They were randomized to receive either gonadotropin releasing hormone agonist (GNRHa), Buserelin, prior to and during induction of ovulation by hMG (Group I—long protocol), or GnRHa starting on the first day of the cycle together with induction of ovulation by hMG (Group II—short protocol). Mean follicular phase serum luteinizing hormone (LH) and progesterone (P) levels were significantly lower in Group I than in Group II (P<0.01). Cancellation rate was significantly lower in Group I than in Group II (P<0.01). The long GNRHa protocol resulted in statistically significant lower cancellation rates, more oocytes per pickup (OPU), more embryos trans-ferred per patient, and a higher pregnancy rate. Significantly more hMG ampoules and more treatments days were required in the long GNRHa protocol. Our data demonstrate that the use of GNRHa prior to and during ovarian stimulation with hMG offers a very good alternative for patients with repetitive unsuccessful IVF cycles due to inadequate response.  相似文献   
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