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61.
The process of “adaptive suckling” has evolved appropriate to the needs of different mammal species. It is related to the maturity of the newborn, nutritional requirements, the number of offspring, the need for sensory stimulation, etc. Examples are given of the following species—the echidna, the kangaroo, the blue whale and.the seal. Its relevance to modern man is discussed.  相似文献   
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An isolated avulsion fracture of the lesser tuberosity is an uncommon injury. We present five cases in adolescent athletes which demonstrate the radiographic, ultrasound, and MR appearances of this injury. Clinically and radiologically, the diagnosis can be difficult. In a setting of trauma, careful review of the imaging studies can lead to early diagnosis and appropriate treatment.  相似文献   
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We report here the affinity and antibacterial activity of a structurally similar class of neomycin dimers. The affinity of the dimer library for rRNA was established by using a screen that measures the displacement of fluorescein-neomycin (F-neo) probe from RNA. A rapid growth inhibition assay using a single drug concentration was used to examine the antibacterial activity. The structure-activity relationship data were then rapidly analyzed using a two-dimensional ribosomal binding-bacterial inhibition plot analysis.  相似文献   
67.
Assembly effectors are small molecules that induce inappropriate virus capsid assembly to antiviral effect. To identify attributes of hepatitis B virus (HBV) assembly effectors, assembly reaction products (normal capsid, noncapsid polymer, intermediates, and free dimeric core protein) were quantified in the presence of three experimental effectors: HAP12, HAP13, and AT-130. Effectors bound stoichiometrically to capsid protein polymers, but not free protein. Thermodynamic and kinetic effects, not aberrant assembly, correlate with maximal antiviral activity.  相似文献   
68.
The ERBB receptors are a family of heterodimerization partners capable of driving transformation and metastasis. While the therapeutic targeting of single receptors has proven efficacious, optimal targeting of this receptor family should target all oncogenic members simultaneously. The juxtamembrane domains of ERBB1, ERBB2, and ERBB3 are highly conserved and control various aspects of ERBB-dependent biology. In an effort to block those functions, we have targeted this domain with decoy peptides synthesized in tandem with a cell-penetrating peptide, termed EJ1. Treatment with EJ1 induces cell death, promotes the formation of inactive ERBB multimers, and results in simultaneous reduction of ERBB1, ERBB2, and ERBB3 activation. Treatment also results in the activation of myosin light chain–dependent cell blebbing while inactivating CaMKII signaling, coincident with the induction of cell death. EJ1 also directly translocates to mitochondria, correlating with a loss of mitochondrial membrane potential and production of reactive oxygen species. Finally, treatment of a mouse model of breast cancer with EJ1 results in the inhibition of tumor growth and metastasis without associated toxicities in normal cells. Overall, these data demonstrate that a portion of the ERBB jxm domain, when used as an intracellular decoy, can inhibit tumor growth and metastasis, representing a novel anticancer therapeutic.  相似文献   
69.
Background Post hoc analyses assessed the prognostic and predictive value of baseline alpha-fetoprotein (AFP), as well as clinical outcomes by AFP response or progression, during treatment in two placebo-controlled trials (REACH, REACH-2).Methods Serum AFP was measured at baseline and every three cycles. The prognostic and predictive value of baseline AFP was assessed by Cox regression models and Subpopulation Treatment Effect Pattern Plot method. Associations between AFP (≥ 20% increase) and radiographic progression and efficacy were assessed.Results Baseline AFP was confirmed as a continuous (REACH, REACH-2; p < 0.0001) and dichotomous (≥400 vs. <400 ng/ml; REACH, p < 0.01) prognostic factor, and was predictive for ramucirumab survival benefit in REACH (p = 0.0042 continuous; p < 0.0001 dichotomous). Time to AFP (hazard ratio [HR] 0.513; p < 0.0001) and radiographic (HR 0.549; p < 0.0001) progression favoured ramucirumab. Association between AFP and radiographic progression was shown for up to 6 (odds ratio [OR] 5.1; p < 0.0001) and 6–12 weeks (OR 1.8; p = 0.0065). AFP response was higher with ramucirumab vs. placebo (p < 0.0001). Survival was longer in patients with an AFP response than patients without (13.6 vs. 5.6 months, HR 0.451; 95% confidence interval, 0.354–0.574; p < 0.0001).Conclusions AFP is an important prognostic factor and a predictive biomarker for ramucirumab survival benefit. AFP ≥ 400 ng/ml is an appropriate selection criterion for ramucirumab.Clinical Trial Registration ClinicalTrials.gov, REACH (NCT01140347) and REACH-2 (NCT02435433).Subject terms: Oncology, Biomarkers  相似文献   
70.
There has been a sharp rise of reported handheld laser-induced maculopathy (HLIM) cases over the past decade, a concerning trend that may continue due to unregulated online access to high power lasers. Though HLIM has distinct clinical features, not uncommonly it may masquerade as other retinal disorders. It is critical therefore to recognise the clinical and multimodal imaging characteristics of this important and potentially devastating condition. As HLIM patients are typically young, unique issues need to be considered, such as delayed presentation, difficult history, poor compliance and behavioural or psychiatric comorbidity. This article will review the clinical and diagnostic features of laser injury, with a special emphasis on the multimodal retinal findings. In addition, we present a unique case of HLIM, resembling the presentation of a placoid disease variant and illustrating choroidal ischaemia using advanced retinal imaging, that offers further insight into the mechanisms of laser injury and its complications. The issues addressed in this review aim to increase recognition of an increasingly important and trending condition with potentially profound visual complications.Subject terms: Retinal diseases, Paediatrics, Trauma  相似文献   
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