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231.
Anthrax is an acute bacterial infection caused by Bacillus anthracis. Humans become infected under natural conditions by contact with infected animals or contaminated animal products. About 95% of human anthrax is cutaneous and 5% respiratory. Gastrointestinal anthrax is very rare, and has been reported in less than 1% of all cases. Anthrax meningitis is a rare complication of any of the other three forms of disease. We report three rare cases of anthrax (gastrointestinal, oropharyngeal and meningitis) arising from the same source. The three patients were from a single family and were admitted with different clinical pictures after the ingestion of half-cooked meat from a sick sheep. These cases emphasize the need for awareness of anthrax in the differential diagnosis in areas where the disease remains endemic.  相似文献   
232.
BackgroundNurses require a great deal of knowledge to provide a comprehensive and effective nursing care. A number of patterns have been put into place to help nurses acquire this knowledge. The aim of this study was to describe the core variable in the process of using patterns of knowing by nurses in clinical practice.MethodsThe study was conducted in qualitative and grounded theory approach, between April 2018 and January 2020. Semi-structured interviews were used for data collection. All the interviews were transcribed verbatim. Nineteen clinical nurses were interviewed, and eight observation sessions were conducted in different hospital departments. Participants were first selected through purposeful and then theoretical sampling. Data were analyzed and interpreted using constant comparison analysis approach.ResultsThe findings of the study indicated that nurses apply the patterns of knowing in three ways in their clinical practice: “cohesion of patterns of knowing”, “domination of some patterns of knowing” and “elimination of some patterns of knowing”. The core variable of this process is cohesion of patterns of knowing in the domain of flexibility.ConclusionThe findings of the present study indicate that application of patterns of knowing is practiced in a range of nurse flexibility in clinical settings.  相似文献   
233.
Efficient neurotransmitter release at the presynaptic terminal requires docking of synaptic vesicles to the active zone membrane and formation of fusion-competent synaptic vesicles near voltage-gated Ca2+ channels. Rab3-interacting molecule (RIM) is a critical active zone organizer, as it recruits Ca2+ channels and activates synaptic vesicle docking and priming via Munc13-1. However, our knowledge about Munc13-independent contributions of RIM to active zone functions is limited. To identify the functions that are solely mediated by RIM, we used genetic manipulations to control RIM and Munc13-1 activity in cultured hippocampal neurons from mice of either sex and compared synaptic ultrastructure and neurotransmission. We found that RIM modulates synaptic vesicle localization in the proximity of the active zone membrane independent of Munc13-1. In another step, both RIM and Munc13 mediate synaptic vesicle docking and priming. In addition, while the activity of both RIM and Munc13-1 is required for Ca2+-evoked release, RIM uniquely controls neurotransmitter release efficiency. However, activity-dependent augmentation of synaptic vesicle pool size relies exclusively on the action of Munc13s. Based on our results, we extend previous findings and propose a refined model in which RIM and Munc13-1 act in overlapping and independent stages of synaptic vesicle localization and release.SIGNIFICANCE STATEMENT The presynaptic active zone is composed of scaffolding proteins that functionally interact to localize synaptic vesicles to release sites, ensuring neurotransmission. Our current knowledge of the presynaptic active zone function relies on structure-function analysis, which has provided detailed information on the network of interactions and the impact of active zone proteins. Yet, the hierarchical, redundant, or independent cooperation of each active zone protein to synapse functions is not fully understood. Rab3-interacting molecule and Munc13 are the two key functionally interacting active zone proteins. Here, we dissected the distinct actions of Rab3-interacting molecule and Munc13-1 from both ultrastructural and physiological aspects. Our findings provide a more detailed view of how these two presynaptic proteins orchestrate their functions to achieve synaptic transmission.  相似文献   
234.
Traumatic early life stress (ELS) is linked to dopamine (DA) dysregulation which increases the probability of developing psychiatric disorders in adolescence and adulthood. Our prior studies demonstrated that a severe early life stressor, a 24-hr maternal deprivation (MD) in juvenile male rats, could lead to altered DA signaling from the ventral tegmental area (VTA) due to impairment of GABAergic synaptic plasticity (promoting GABAergic long-term depression, LTD) with concomitant changes in the abundance of synaptic regulators including A-kinase anchoring protein (AKAP150). Importantly, these MD-induced synaptic changes in the VTA were accompanied by upregulation of histone deacetylase 2, histone hypoacetylation, and were reversible by HDAC inhibition. Using cell-attached and whole-cell patch clamp recordings, we found that MD stress also increased spontaneous VTA DA neuronal activity and excitability in juvenile male rats without affecting intrinsic excitability. Postsynaptic chemical disruption of AKAP150 and protein kinase A interaction increased VTA DA neuronal excitability in control non-MD rats mimicking the effects of MD on DA cell excitability with similar changes in membrane properties. Interestingly, this disruption decreased MD-induced VTA DA hyperexcitability. This MD-induced DA neuronal hyperexcitability could also be normalized at 24 hr after injection of the class 1 HDAC inhibitor, CI-994. Altogether, our data suggest that AKAP150 plays a critical role in the regulation of VTA DA neuronal excitability and that HDAC-mediated targeting of AKAP150 signaling could normalize VTA DA dysfunction following ELS thereby providing novel therapeutic targets for prevention of later life psychopathology.  相似文献   
235.
At least 50% of infertile couple's problems are related to male factor infertility. This Randomized, Double‐Blind, Placebo‐Controlled Clinical Trial conducted in Urology unit of Infertility Clinic on 60 infertile men. Patients were randomly assigned to one of intervention and placebo (n = 30) groups. Finally, 28 subjects in each group completed the study. Participants in the intervention group took daily 80 mg curcumin nanomicelle and those in the placebo group took daily placebo for 10 weeks. Semen analysis, anthropometric, physical activity assessments, total antioxidant capacity, malondialdehyde, inflammatory factors, and reproductive hormones were measured at the baseline and at the end of the study. At the end of study, statistically significant differences were seen in the total sperm count, sperm concentration, and motility in the intervention group to the control group. In treatment group, the total sperm count, sperm concentration, and motility levels were also statistically increased at the end of study compared to the baseline values. Curcumin nanomicelle supplementation also resulted in a statistically significant improvement in plasma levels of total antioxidant capacity, malondialdehyde, C‐reactive protein, and tumor necrosis factor a in comparison to the placebo. Medical therapy of asthenoteratospermia with curcumin nanomicelle supplement could improve quality of semen parameters. However, further investigation is suggested in this regard.  相似文献   
236.
Previous studies have shown that the presence of hippocampal theta activity is important for learning and memory, and that the medial supramammillary nucleus (mSuM) is involved in the control of the frequency of theta rhythm. It has also been shown that the depression of mSuM activity by chlordiazepoxide causes modest impairment of spatial learning. On the other hand, the lateral supramammillary nucleus (lSum) increases long-term potentiation (LTP) of hippocampal population spikes. However, to our knowledge, no reports exist concerning the role of the supramammillary area (SuM) in passive avoidance (PA) learning. In the present study, rats were chronically implanted with a cannula aimed at SuM and were trained on a step-through PA task. They received intra-SuM injection of lidocaine or saline at the following intervals: 5 min before training, 5, 90, and 360 min after the acquisition trial, or 5 min before the retrieval test. When lidocaine was injected 5 min before training there was no effect on acquisition of PA but retrieval was significantly poorer than the control group injected with saline. Lidocaine injection 5 min after the acquisition trial impaired PA retention, but reversible inactivation of SuM at 90 and 360 min after training and 5 min before the retrieval test showed no significant effect on PA retention. It can be concluded that SuM contributes to PA consolidation at least 5 min after the acquisition trial and that this effect may be accomplished through SuM projections to the septal and/or hippocampal areas participating in the PA memorization processes.  相似文献   
237.
Sixty-three pediatric patients with germ cell tumors are presented with details of symptoms, histological findings, staging, serological markers, treatment, and response to therapy. The primary sites were: ovarian 32, testicular 17, presacral 7, mediastinal 3, intraabdominal 2, vaginal 1, and right inguinal canal 1. These patients were treated with T2 (sequential use of dactinomycin, doxorubicin, vincristine, and cyclophosphamide, with or without radiation), T6 (combination chemotherapy with cyclo-phosphamide, bleomycin, dactinomycin, doxorubicin, methotrexate, vincristine), or VAB treatment protocols (velban, dactinomycin, bleomycin, cisplatin). The cure rate for stage I ovarian and testicular germ cell tumors was 100%; for stage III, all primary sites, 82% and for stage IV, all primary sites, 75%. Histology was prognostic in ovarian tumors of the immature malignant teratoma type; the neural type immature teratoma, grades II and III, had the worst prognosis. Initial debulking surgery in combination with chemotherapy and radiation plays an important role in germ cell tumors. Stages II, III, and IV germ cell tumors require aggressive treatment with surgery, radiation, and chemotherapy. For stage I patients, with primary ovarian malignant tumor, cure with surgery alone can be achieved in 50% of the cases and in testicular tumors in about 70% of the patients. For those with stage I and elevated serological markers, it is feasible to follow these markers and give no treatment until there is evidence of persistent elevation or a rise in titers after an initial fall. In those without elevated serological markers, one should take into consideration the size of the tumor and the histological type before taking the “wait and see” approach. These stage I tumors are highly curable when they first present but, if allowed to recur, chemotherapy may not offer the patient such a favorable response and cure rate.  相似文献   
238.
The canal of Nuck is a remnant of a peritoneal evagination associated with the round ligament in women. Rarely, the canal of Nuck can remain patent allowing for development of cysts. These cysts are difficult to diagnose due to their rare incidence and because they are often mistaken for other causes of inguinal pain in women. This case series of three women presenting with groin or labial masses highlights the role of sonography as the primary imaging modality in the diagnosis of canal of Nuck cysts. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45 :175–178, 2017  相似文献   
239.
Hyaluronic Acid (HA) is a non-sulfated glycosaminoglycan, which is a potential biomarker that could be evaluated in the diagnosis of some cancers. For the first time, a novel label-free electrochemical immunosensor was developed based on modified ITO-PET (indium tin oxide-polyethylene terephthalate) electrodes for the sensitive recognition of hyaluronic acid (HA) in real samples. A disposable ITO-coated PET electrode was modified with gold nanoparticles (AuNPs) to construct a suitable substrate for the efficient immobilization of biotinylated antibodies of HA. Importantly, the encapsulation of biotinylated antibody of HA in KCC1-NH-CS2 was performed successfully, which was another innovative part of this bio-device construction. For determining the immobilization steps and optimization of the biosensor, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques were used. Furthermore, the morphological characterization of each ITO electrode surface was performed by field emission scanning electron microscopy (FESEM). Specific binding of gold nanoparticles supported CTAB to ITO-PET and its bioconjugation with the biotinylated antibody of HA was studied using the electroanalysis of the sensor performance. For the better performance of the antibody to generate an immunocomplex with HA (antigen), its encapsulation was performed, which led to the excellent behavior of the immunosensor. The proposed HA immunosensor indicated excellent reproducibility, high selectivity, and long-term stability. The HA electrochemical immunosensor performed perfectly with a wide determination range (0.078 to 160 ng mL−1) and a low limit of quantification (0.078 ng mL−1) in human plasma samples. It is recommended that the designed biosensor can be used as a diagnostic tool in clinical bioassays in the near future.

Hyaluronic Acid (HA) is a non-sulfated glycosaminoglycan, which is a potential biomarker that could be evaluated in the diagnosis of some cancers.  相似文献   
240.
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