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1.
The tetrasaccharides GalNAcß1-4[NeuAc2-3]Galß1-4Glc and GalNAcß1-4[NeuAc2-3]Galß1-4GlcNAc were synthesised by enzymic transfer of GalNAc from UDP-GalNAc to 3-sialyllactose (NeuAc2-3Galß1-4Glc) and 3-sialyl-N-acetyllactosamine (NeuAc2-3Galß1-4GlcNAc). The structures of the products were established by methylation and1H-500 MHz NMR spectroscopy. In Sda serological tests the product formed with 3-sialyl-N-acetyllactosamine was highly active whereas that formed with 3-sialyllactose had only weak activity.  相似文献   
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Catecholamines induce net salt and water movements in duck red cells incubated in isotonic solutions. The rate of this response is approximately three times greater than a comparable effect observed in 400 mosmol hypertonic solutions in the absence of hormone (W.F. Schmidt and T. J. McManus. 1977 a.J. Gen. Physiol. 70:59-79. Otherwise, these two systems share a great many similarities. In both cases, net water and salt movements have a marked dependence on external cation concentrations, are sensitive to furosemide and insensitive to ouabain, and allow the substitution of rubidium for external potassium. In the presence of ouabain, but the absence of external potassium (or rubidium), a furosemide-sensitive net extrusion of sodium against a large electrochemical gradient can be demonstrated. When norepinephrine-treated cells are incubated with ouabain and sufficient external sodium, the furosemide-sensitive, unidirectional influxes of both sodium and rubidium are half- maximally saturated at similar rubidium concentrations; with saturating external rubidium, the same fluxes are half-maximal at comparable levels of external sodium. In the absence of sodium, a catecholamine-stimulated, furosemide-sensitive influx of rubidium persists. In the absence of rubidium, a similar but smaller component of sodium influx can be seen. We interpret these results in terms of a cotransport model for sodium plus potassium which is activated by hypertonicity or norepinephrine. When either ion is absent from the incubation medium, the system promotes an exchange-diffusion type of movement of the co-ion into the cells. In the absence of external potassium, net movement of potassium out of the cell leads to a coupled extrusion of sodium against its electrochemical gradient.  相似文献   
3.
Summary A mixture of 1-naphthylacetic acid and 6-benzylaminopurine was found to be an effective substitute for the rhizome apex of attached rhizomes, when the plants were not at anthesis. The same mixture was not effective, however, when the plants were at anthesis. The same growth-regulators applied to the apical end of detached multi-node rhizome fragments did not maintain correlative inhibition unless growth-regulators were simultaneously applied to the basal end. Various interactions between apical and basal applications are discussed with regard to their role as a parental factor in apical dominance.Abbreviations NAA 1-naphthyl acetic acid - BAP 6-benzylaminopurine - ABA abcisic acid - IAA indole-3-acetic acid  相似文献   
4.
Here, we describe a fast, easy-to-use, and sensitive method to profile in-depth structural micro-heterogeneity, including intricate N-glycosylation profiles, of monoclonal antibodies at the native intact protein level by means of mass spectrometry using a recently introduced modified Orbitrap Exactive Plus mass spectrometer. We demonstrate the versatility of our method to probe structural micro-heterogeneity by describing the analysis of three types of molecules: (1) a non-covalently bound IgG4 hinge deleted full-antibody in equilibrium with its half-antibody, (2) IgG4 mutants exhibiting highly complex glycosylation profiles, and (3) antibody-drug conjugates. Using the modified instrument, we obtain baseline separation and accurate mass determination of all different proteoforms that may be induced, for example, by glycosylation, drug loading and partial peptide backbone-truncation. We show that our method can handle highly complex glycosylation profiles, identifying more than 20 different glycoforms per monoclonal antibody preparation and more than 30 proteoforms on a single highly purified antibody. In analyzing antibody-drug conjugates, our method also easily identifies and quantifies more than 15 structurally different proteoforms that may result from the collective differences in drug loading and glycosylation. The method presented here will aid in the comprehensive analytical and functional characterization of protein micro-heterogeneity, which is crucial for successful development and manufacturing of therapeutic antibodies  相似文献   
5.
Newer agents and procedures give urologists more options in treating patients who have urinary incontinence related to such etiologies as an ineffective sphincter, detrusor hypersensitivity, obstruction, or a combination of these. Abolition of the involuntary contractions characteristic of detrusor instability can be accomplished pharmacologically or surgically. First-line anticholinergic agents are tolterodine and oxybutynin XL, given orally. Alternatively, intravesical administration provides a high concentration of drug, such as capsaicin or resiniferatoxin, at the detrusor muscle level. However, this commits the patient to intermittent self-catheterization. Surgery is reserved for those who have failed prolonged trials of conservative therapies. For patients with intractable urge incontinence, urologists have the new technique of sacral nerve stimulation.  相似文献   
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Stress urinary incontinence (SUI) involves involuntary leakage of urine in response to abdominal pressure caused by activities such as sneezing and coughing. The condition affects millions of women worldwide, causing physical discomfort as well as social distress and even social isolation. Until recently, SUI was approached by clinicians as a purely anatomic problem requiring behavioral or surgical therapy. Over the past several years, extensive basic and clinical research in the field of neurourology has enhanced our understanding of the complex neural circuitry regulating normal function of the lower urinary tract. As a result, novel concepts have emerged regarding possible neurologic dysfunctions that might underlie the development of SUI, as well as potential novel strategies for pharmacologic therapy. This article reviews the normal neurophysiologic control of lower urinary tract function and considers potential pharmacologic approaches to correcting SUI.  相似文献   
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At the University of Pittsburgh School of Medicine, our experience with urethrolysis over the past several years offered a unique opportunity to assess outcomes after delayed time to urethrolysis. We observed a highly suggestive association between prolonged time to urethrolysis and a greater likelihood of persistent bladder dysfunction. If this observation is corroborated by other studies, it would be prudent to lower our threshold of clinical suspicion to detect bladder outlet obstruction. Videourodynamics testing can be invaluable for making the distinction between outlet obstruction versus de novo urge incontinence. Here, we briefly review the literature on urethrolysis and present the urethrolysis technique utilized at our institution. The article concludes with several challenging and controversial clinical judgment questions asked ofDr Leng by Dr Chancellor.  相似文献   
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