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101.
Bevacizumab--current status and future directions. 总被引:13,自引:0,他引:13
Angiogenesis is crucial to tumour initiation, survival and metastasis. Vascular endothelial growth factor (VEGF) is one of the most important pro-angiogenic factors in cancer development. Bevacizumab (a humanised monoclonal antibody against VEGF) has a reasonable safety profile and proven efficacy in a phase III trial in advanced colorectal cancer. Efficacy of Bevacizumab also looks promising in non small cell lung cancer, renal cancer and a variety of other solid tumours. Questions still surround optimal dosing and the appropriate selection of patients who are most likely to benefit. Future trials will address these questions and provide further translational insights. 相似文献
102.
Embryonic germ cells (EGCs) are pluripotent stem cells derived from primordial germ cells (PGCs). PGCs are progenitors of adult gametes, which diverge from the somatic lineage between late embryonic to early fetal development. First derived in the mouse, EGCs have also been derived from human, chicken, and pig. As pluripotent stem cells, EGCs demonstrate long-term self-renewal via clonal expansion in an undifferentiated state, and differentiate in vitro to form embryoid bodies containing cells that represent all three germ layers as well as mixed cell populations of less differentiated progenitors and precursors. This is also demonstrated in vivo by their formation into experimentally induced teratocarcinomas following transplantation. Furthermore, mice, pig, and chicken EGCs have also been shown to contribute to experimentally produced chimeric animals, including germline transmission. Importantly, EGCs demonstrate normal and stable karyotypes as well as normal patterns of genomic imprinting, including X-inactivation. Transplantation studies have begun in a variety of models in hopes of defining their potential use to treat a wide variety of human conditions, including diabetes and urological and neurological disorders. 相似文献
103.
Pregnenolone and its sulphate had concentration-dependent dual actions on gamma-aminobutyric acid (GABAA)-receptor-mediated ileal contractile responses, enhancing at 0.001-1 microM but inhibiting at 10 microM. There was a sinistral shift of the GABA dose-response curve in the presence of 0.01 microM pregnenolone, with a significant potentiation over the lower concentration range of GABA (3-30 microM), whilst 10 microM pregnenolone depressed the curve by 50% without a significant change in the EC50, in a manner resembling non-competitive inhibition with picrotoxin. Pregnenolone and its sulphate evidently have modulatory actions at ileal GABAA-receptor complexes in keeping with those seen using neurochemical studies in the central nervous system. 相似文献
104.
Wever G. K. Althausen T. L. Biskind G. R. Kerr WM. J. 《The American journal of digestive diseases》1935,2(2):93-99
The American Journal of Digestive Diseases - In our patients with acute hepatitis, as a group, the Rose Bengal test was positive in 94 per cent, and the modified glucose tolerance test in 93 per... 相似文献
106.
Forty-two workers from a chemical plant producing inorganic mercury compounds were evaluated for neurologic, nephrotic, and ophthalomogic toxicity. Despite elevated blood and urinary mercury levels, routine clinical testing such as physical examination, blood chemistries, and urinalysis were generally normal. These findings from the routine examination are in contrast to the complaints of neuropsychological symptoms, elevated urinary n-acetyl B-D-glucosaminidase (NAG) levels, decreased motor nerve conduction velocities, and the presence of lenticular opacities on slit-lamp examination that were found, when organ systems known to be affected by mercury were targeted. More sensitive but objective indicators of toxicity need to be included in routine medical screening so as to help diagnose the etiology of neuropsychological symptoms and prevent long-term sequelae in workers exposed to mercury. 相似文献
107.
Lorin E. Kerr MD 《Archives of environmental & occupational health》2013,68(4):579-585
The capacitance respirometer is a new device for measuring respiratory volumes and flow rates. Surface area changes of the abdomen and rib cage during respiration are defected and related to the inspired and expired gas volumes. Except for calibrating, human lung function testing is quickly accomplished and recorded without a mouthpiece, nose clip, or any other type of external attachment. 相似文献
108.
Therese I. Poirier Theresa M. Kerr Stephanie J. Phelps 《American journal of pharmaceutical education》2013,77(2)
Objective. To describe academic progression and retention policies used by US colleges and schools of pharmacy.Methods. Student handbooks on the Web sites of 122 colleges and schools of pharmacy were reviewed between February 2012 and May 2012.Results. Data were available and obtained from 98 (80%) programs. Most used grade point average (GPA) as a criterion for progression, with 66% requiring a minimum GPA of 2.0. Cumulative GPA was the most frequently used criteria for probation. Most handbooks did not address remediation, but 38% noted that a failed course could only be retaken once. The most common criteria for dismissal were the cumulative number of times a student was on probation. The graduation requirements of most programs were a cumulative GPA of 2.0 and completion of the program within 6 years of enrollment. Conclusions. Colleges and schools of pharmacy use various criteria for academic progression and retention and frequently provide incomplete or inadequate information related to probation, progression, and dismissal. Information regarding remediation and academic performance during experiential learning is lacking. A clearinghouse containing institutional data related to progression and retention would assist programs in developing academic policies. The study also highlights the need for ACPE to ensure this information is provided to students. 相似文献
109.
110.
A discussion of functional bowel disturbances is presented, using the term irritable bowel syndrome. Etiologic factors are discussed and a useful classification is proposed. The diagnosis of the irritable bowel syndrome must be made by exclusion as well as by positive features, because identical symptoms are often produced by organic lesions. Psychotherapy and diet, as well as medication, are discussed in connection with treatment. 相似文献