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991.
AimsAcoustic neuromas are rare, benign intracranial tumours. There are a variety of treatment options, with no clear optimal management strategy and wide variation in treated outcomes. We report the outcomes from a 15 year cohort of patients treated at our centre using fractionated stereotactic radiotherapy (52.5 Gy in 25 fractions).Materials and methodsWe analysed a retrospective case series. Patients were identified from patient records and a retrospective review of case notes and imaging reports was undertaken. We assessed tumour response using RECIST criteria and recorded toxicity. Progression-free survival was estimated using the Kaplan–Meier method. The study was conducted according to the STROBE guidelines.ResultsIn total, 93 patients were identified; 83 patients had follow-up data, with a median follow-up period of 5.7 years. The overall control rate using RECIST criteria was 92%. Data on complications were available for 90 patients, with six (7%) experiencing a reduction in hearing, one (1%) developing trigeminal nerve dysfunction and one (1%) a deterioration in facial nerve function. Other toxicities included four (4%) patients who developed hydrocephalus, requiring the placement of a shunt and one (1%) patient who developed radiation brainstem necrosis. After further evaluation this patient was deemed to have been treated within acceptable dose constraints.ConclusionThese data suggest that a good control rate of acoustic neuromas is achievable using fractionated stereotactic radiotherapy to a dose of 52.5 Gy in 25 fractions. Toxicity is considered acceptable but the episode of radiation brainstem necrosis remains of concern and is the subject of further work.  相似文献   
992.
993.
金厅  陈晓钟 《肿瘤学杂志》2020,26(4):301-308
中国科学院大学附属肿瘤医院近年来就鼻咽癌诊治开展了数十项研究,这些研究大部分是针对Ⅱ期、局部晚期、转移鼻咽癌的治疗干预性研究,其余的是针对预后因素、分期以及放疗毒副反应的研究。全文就这数十项研究作一综述,一方面是对浙江省鼻咽癌学科发展的宣传与肯定,另一方面为临床医师合理制定临床治疗策略提供一些参考,也为扩大国内外鼻咽癌学科的交流和发展提供契机。  相似文献   
994.
Therapeutic proteins are exposed to various potential contact surfaces, particles, and leachables during manufacturing, shipping, storage, and delivery. In this review, we present published examples of interfacial- or leachable-induced aggregation or particle formation, and discuss the mitigation strategies that were successfully utilized. Adsorption to interfaces or interactions with leachables and/or particles in some cases has been reported to cause protein aggregationor particle formation. Identification of the cause(s) of particle formation involving minute amounts of protein over extended periods of time can be challenging. Various formulation strategies such as addition of a nonionic surfactant (e.g., polysorbate) have been demonstrated to effectively mitigate adsorption-induced protein aggregation. However, not all stability problems associated with interfaces or leachables are best resolved by formulation optimization. Detectable leachables do not necessarily have any adverse impact on the protein but control of the leachable source is preferred when there is a concern. In other cases, preventing protein aggregation and particle formation may require manufacturing process and/or equipment changes, use ofcompatible materials at contact interfaces, and so on. This review summarizes approaches that have been used to minimize protein aggregation and particle formation during manufacturing and fill–finish operations, product storage and transportation, anddelivery of protein therapeutics. © 2011 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 100:4158–4170, 2011  相似文献   
995.
Emerging evidence for the early introduction of allergenic foods for the prevention of food allergies, such as peanut allergy in Western populations, has led to the recent publication of guidelines in the USA and Europe recommending early peanut introduction for high‐risk infants with severe eczema or egg allergy. Peanut allergy is, however, much less prevalent in Asia compared to the West. Varying patterns of food allergy are seen even within Asian countries—such as a predominance of wheat allergy in Japan and Thailand and shellfish allergy in Singapore and the Philippines. Customs and traditions, such as diet and infant feeding practices, also differ between Asian populations. Hence, there are unique challenges in adapting guidelines on early allergenic food introduction to the Asian setting. In this paper, we review the evidence and discuss the possible approaches to guide the timely introduction of allergenic food in high‐risk infants in Asia.  相似文献   
996.
The data presented here demonstrate that recombinant human tumour necrosis factor beta (rHuTNF beta; lymphotoxin) is a neutrophil modulator. The lymphokine inhibited the locomotion of neutrophils and augmented the neutrophil oxygen-dependent respiratory burst in response to N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP) and phorbol myristate acetate (PMA), as measured by their capacity to produce chemiluminescence, H2O2 and superoxide. The effects on the respiratory burst occurred at a tenth of the concentration of TNF beta required to inhibit locomotion. After incubation with TNF beta, the neutrophils could be washed without any reduction in their capacity to show augmented responses. The TNF beta enhanced granule enzyme (lysozyme and beta-glucuronidase) release of neutrophils stimulated with cytochalasin B-FMLP.  相似文献   
997.
998.
Summary.  An in vitro orchid protoplast isolation method to study replication kinetics of CymMV and ORSV was developed. This method allows the isolation of viable and raphid-free petal protoplasts from an orchid hybrid, {\it Dendrobium} Sonia (Dendrobium Caesar × Dendrobium Tomie Drake). The optimum field strength for both viral RNA to achieve good efficiency of electroporation was 750 V/cm and the optimum viral RNA concentration required was 1 μg and 4 μg per 2 × 106 protoplasts for CymMV and ORSV, respectively. Autoradiographs of Northern blots depicting the viral genomic and subgenomic RNA in the extracts, referred to as the “Replication Footprint Profiles” (RFP) of specific CymMV/ORSV virus were prepared at different time intervals. Viral RNA synthesis reached a maximum at 18 h for CymMV and 24 h for ORSV. When CymMV and ORSV viral RNA were electroporated into the protoplasts simultaneously, detection signals of both the positive and negative strand viral RNA increased as compared to the singly infected protoplasts. Thus, synergism in replication of CymMV and ORSV was observed in orchid protoplasts. Received November 20, 1997 Accepted February 25, 1998  相似文献   
999.
Invasive aspergillosis is a serious complication in immunocompromised patients. The effects of recombinant human tumor necrosis factor alpha (TNF-α) on antifungal activities of human neutrophils (polymorphonuclear leukocytes [PMNs]), human monocytes (MNCs), and rabbit pulmonary alveolar macrophages (PAMs) against Aspergillus fumigatus were studied. The percentage of PMN-induced hyphal damage was increased after 30 min of incubation of PMNs with 0.1 ng of TNF-α per ml at 37°C (P = 0.043). At 0.1 to 10 ng/ml, TNF-α also increased superoxide anion (O2) produced by PMNs in response to phorbol myristate acetate, N-formylmethionyl leucyl phenylalanine, and unopsonized hyphae (P < 0.01) but did not exert any effect on PMN phagocytosis of conidia in the presence of serum. By comparison, TNF-α induced only a slight increase in O2 production by MNCs in response to phorbol myristate acetate (P = 0.05) and no concomitant increase in the percentage of MNC-induced hyphal damage. Incubation of MNCs with TNF-α at 0.001 to 10 ng/ml for 2 days had no effect on phagocytosis or conidiocidal activity. By contrast, incubation of PAMs with TNF-α at 0.1 to 10 ng/ml for 2 days increased phagocytosis of conidia (P = 0.03). Thus, TNF-α augments the capacity of PMNs to damage Aspergillus hyphae, possibly through enhanced oxidative mechanisms, and increases PAM phagocytic activity against conidia. As such, TNF-α may have an important role in host defense against aspergillosis, and neutralization of its activity may be complicated by increased susceptibility to aspergillosis.  相似文献   
1000.

Objectives

Defective implantation is a mechanism for recurrent pregnancy loss (RPL). We sought to determine whether the serum expression of human relaxin-2 (RLX) is impaired in women with a history of RPL.

Study design

Employing a prospective case-controlled design we studied 20 pregnant women with a history of RPL and 20 age-matched women with no history of RPL (NRPL). We measured serum relaxin-2 levels by ELISA at 6–8, 10–12, 20, and 34 weeks gestation and in cord blood, and maternal uterine artery Doppler resistance index (RI) at ≥10 weeks gestation.

Results

Relaxin rose to a peak at 12 weeks, and gradually declined towards term. At all gestations, women with a history of RPL had lower RLX levels than women without. At 10–12 weeks gestation, uterine artery RI correlated with serum RLX for both RPL and NRPL. In the NRPL group at 10–12 weeks the presence of a notched waveform was associated with higher RLX levels than the absence of a notch (mean 2.1 ng/ml vs. 1.3 ng/ml, P < 0.05) and also at 20 weeks (2.1 ng/ml vs. 0.95 ng/ml, P < 0.05) but no such difference was seen in the RPL group. Umbilical venous RLX was 4-fold higher in the RPL group than the NRPL group.

Conclusion

Women with a history of RPL demonstrate attenuated levels of serum RLX across all pregnancy trimesters. How dysregulated RLX metabolism may contribute to adverse pregnancy outcome in RPL requires further investigation.  相似文献   
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