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61.
A near infrared spectroscopic method was developed to determine drug content in a 20% (wt/wt) ibuprofen and spray-dried hydous
lactose blend. A blending profile was obtained after blending for 0.5, 1, 3, 5, 10, and 20 minutes. Stream sampling was used
to collect about 20 blend samples at each of the blending times from a laboratory scale V-blender. The samples collected were
used to develop a near infrared calibration model. The calibration model was then used to determine the drug content of unknown
samples from 2 validation blends. The validation blends were not included in the calibration model; they were used to evaluate
the effectiveness of the calibration model. A total of 45 samples from the 2 validation blends were predicted by the near
infrared calibration model and then analyzed by a validated UV spectrophotometric method. The root mean square error of prediction
for the first validation blend was 5.69 mg/g and 3.30 mg/g for the samples from the second blend. A paired t test at the 95%
confidence level did not indicate any differences between the drug content predicted by the near infrared spectroscopy (NIRS)
method and the validated UV method for the 2 blends. The results show that the NIRS method could be developed while the blending
profile is generated and used to thoroughly characterize a new formulation during development by analyzing a large number
of samples. The new formulation could be transferred to a manufacturing plant with an NIRS method to facilitate blend uniformity
analysis. 相似文献
62.
Image processing,diagnostic information extraction and quantitative assessment in pathology 总被引:1,自引:1,他引:0
Santinelli A Mazzucchelli R Colanzi P Tinca A Montironi R 《Journal of cellular and molecular medicine》2002,6(1):93-106
As we enter the information age we hold strong beliefs in the benefits of digital technology applied to pathology: numerical representation offers objectivity . Digital knowledge may indeed lead to significant information discovery, and, processing systems might be designed to allow a true evolution of capabilities. Questions arise whether the methodology underlying quantitative analysis provides the information that we need and whether it is appropriate for some of the problems encountered in diagnostic and prognostic histopathology. While one certainly would not dispute the value of statistical procedures, the clinical needs call for individual patient targeted prognosis. 相似文献
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64.
Maria Antonietta Stazi Rodolfo Cotichini Valeria Patriarca Sonia Brescianini Corrado Fagnani Cristina D'Ippolito Stefania Cannoni Giovanni Ristori Marco Salvetti 《Twin research》2002,5(5):382-386
The unique opportunity given by the "fiscal code", an alphanumeric identification with demographic information on any single person residing in Italy, introduced in 1976 by the Ministry of Finance, allowed a database of all potential Italian twins to be created. This database contains up to now name, surname, date and place of birth and home address of about 1,300,000 "possible twins". Even though we estimated an excess of 40% of pseudo-twins, this still is the world's largest twin population ever collected. The database of possible twins is currently used in population-based studies on multiple sclerosis, Alzheimer's disease, celiac disease, and type 1 diabetes. A system is currently being developed for linking the database with data from mortality and cancer registries. In 2001, the Italian Government, through the Ministry of Health, financed a broad national research program on twin studies, including the establishment of a national twin registry. Among all the possible twins, a sample of 500,000 individuals are going to be contacted and we expect to enrol around 120,000 real twin pairs in a formal Twin Registry. According to available financial resources, a sub sample of the enrolled population will be asked to donate DNA. A biological bank from twins will be then implemented, guaranteeing information on future etiological questions regarding genetic and modifiable factors for physical impairment and disability, cancers, cardiovascular diseases and other age related chronic illnesses. 相似文献
65.
The adaptor protein APS is a substrate of the insulin receptor and couples receptor activation with phosphorylation of Cbl to facilitate glucose uptake. The interaction with the activated insulin receptor is mediated by the Src homology 2 (SH2) domain of APS. Here, we present the crystal structure of the APS SH2 domain in complex with the phosphorylated tyrosine kinase domain of the insulin receptor. The structure reveals a novel dimeric configuration of the APS SH2 domain, wherein the C-terminal half of each protomer is structurally divergent from conventional, monomeric SH2 domains. The APS SH2 dimer engages two kinase molecules, with pTyr-1158 of the kinase activation loop bound in the canonical phosphotyrosine binding pocket of the SH2 domain and a second phosphotyrosine, pTyr-1162, coordinated by two lysine residues in beta strand D. This structure provides a molecular visualization of one of the initial downstream recruitment events following insulin activation of its dimeric receptor. 相似文献
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67.
Ungerfeld R Suárez G Carbajal B Silva L Laca M Forsberg M Rubianes E 《Theriogenology》2003,60(1):35-45
The "ram effect" (RE) is an inexpensive technique that allows farmers to obtain out-of-season lambs. Five hundred and ninety-six Corriedale ewes were used in three experiments to determine the effectiveness of different medroxyprogesterone (MAP) treatments associated with the ram effect during the nonbreeding season. The aim of the first experiment was to evaluate the effectiveness of short-term (6-day) MAP priming. We obtained similar results in estrus incidence and fertility after using MAP sponges for 6, 9, and 13 days. In the second experiment, we compared the effect of sponges containing 20, 40, or 60 mg of MAP used in 6-day priming. Estrous behavior and fertility were not affected by dosage. In the third experiment, 2.5mg of MAP was administered in single treatments 0, 1, 3, or 5 days before the introduction of the rams. Medroxyprogesterone administration 1, 3, or 5 days before the introduction of the rams concentrated estrus in ewes 17 to 20 days later. 相似文献
68.
Concha MI Molina S Oyarzún C Villanueva J Amthauer R 《Fish & shellfish immunology》2003,14(3):259-273
Antimicrobial proteins and peptides play an important role in the primary defence of epithelial barriers in vertebrates and invertebrates. Here we report the detection of the apolipoproteins A-I and A-II in the epidermis and epidermal mucus of the carp (Cyprinus carpio L.) by immunohistochemistry and Western blot analysis. Both apolipoproteins are major constituents of high density lipoprotein and have been shown to display antiviral and antimicrobial activity in mammals. Therefore the aim of this study was to evaluate if they could be part of the innate immune system of teleost fish. A cDNA clone containing most of the coding region for carp apoA-I was isolated and used as a probe to demonstrate the expression of apoA-I gene in the skin. In addition, mucus apoA-I was shown to be associated to small particles that could correspond to nascent HDL. Finally, affinity purified plasma HDL displayed bactericidal activity in vitro against a non-pathogenic Escherichia coli strain, suggesting a defensive role for HDL and its associated proteins in the carp epidermis and mucus. 相似文献
69.
The ubiquitin-like hPLIC proteins can associate with proteasomes, and hPLIC overexpression can specifically interfere with ubiquitin-mediated proteolysis (Kleijnen et al., 2000). Because the hPLIC proteins can also interact with certain E3 ubiquitin protein ligases, they may provide a link between the ubiquitination and proteasomal degradation machineries. The amino-terminal ubiquitin-like (ubl) domain is a proteasome-binding domain. Herein, we report that there is a second proteasome-binding domain in hPLIC-2: the carboxyl-terminal ubiquitin-associated (uba) domain. Coimmunoprecipitation experiments of wild-type and mutant hPLIC proteins revealed that the ubl and uba domains each contribute independently to hPLIC-2-proteasome binding. There is specificity for the interaction of the hPLIC-2 uba domain with proteasomes, because uba domains from several other proteins failed to bind proteasomes. Furthermore, the binding of uba domains to polyubiquitinated proteins does not seem to be sufficient for the proteasome binding. Finally, the uba domain is necessary for the ability of full-length hPLIC-2 to interfere with the ubiquitin-mediated proteolysis of p53. The PLIC uba domain has been reported to bind and affect the functions of proteins such as GABAA receptor and presenilins. It is possible that the function of these proteins may be regulated or mediated through proteasomal degradation pathways. 相似文献
70.