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More than 700,000 people have a stroke each year in the United States. A diagnosis of stroke formerly elicited a nihilistic approach, but this has substantially changed in the last decade. Currently, time is brain, and it is important for all disciplines to work together to initiate acute stroke protocols in the emergency department and identify patients within the therapeutic time window for thrombolytic and neuroprotective therapies. Evolving protocols, management, and nursing care all have important implications during the acute phase of ischemic stroke. Patient and family education on risk reduction must also be addressed by the entire healthcare team.  相似文献   
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Uroscopy in the 21st century: high-field NMR spectroscopy   总被引:1,自引:1,他引:0  
From the experiments described, it can be seen that there are different research approaches that can be taken and these are summarized in Table 1. Whereas much scientific research is principally hypothesis led, there remains, nevertheless, an important place for exploratory research. High resolution NMR can measure, directly and simultaneously, a wide range of endogenous metabolites in biological fluids and has the unique capability of providing structural information on the metabolites detected. It has proved to be a powerful research tool with which to study inherited metabolic diseases, renal disease, drug metabolism, and toxicity, and can be used to monitor the effects of drug therapy. For instance, by using a library of experimental toxins one can map the metabolic profile of site-specific nephron injury. With this approach in man one could eventually take an unknown disease such as Balkan nephropathy and predict the initial site of tubular injury, the mode of injury and therefore the kind of toxin capable of producing that injury. NMR spectroscopic techniques are still advancing rapidly, with ever increasing sensitivity and sophistication of NMR pulse sequences to enhance structural elucidation in complex mixtures. Given the advances in directly coupled HPLC-NMR and even HPLC-NMR-mass spectroscopy it is likely that these technologies in conjunction with pattern recognition will make major contribution to our understanding of renal processes and provide new diagnostic insights in the 21st century.   相似文献   
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The effect of the relative affinity (Ka) on the antitumor efficacy of monoclonal antibodies (MAbs) has been questioned. It has previously been shown in experimental models that the use of MAbs with higher relative Kas manifests itself in a higher percentage of injected dose of MAb bound to tumor. On the other hand, mathematical models have proposed that the use of higher affinity MAbs may be disadvantageous for antitumor effects, since higher Ka MAbs would bind more antigen and prevent penetration of MAb through tumor. To test this hypothesis, three MAbs reacting to the human pancarcinoma antigen TAG-72 were used as radioimmunoconjugates for therapeutic efficacy versus the LS-174T human colon carcinoma xenograft. MAbs B72.3, CC49, and CC83 have all been shown by depletion studies to react to the same molecule and to all react with overlapping epitopes. While the relative Ka of B72.3 is 2.5 x 10(9) M-1, the relative Kas of CC49 and CC83 are 16.2 and 27.7 x 10(9) M-1, respectively. Each MAb was radiolabeled with 131I, and each radioimmunoconjugate was assayed at five dose levels for therapeutic efficacy using the human xenograft model. The results of these studies demonstrate substantial therapeutic advantage of the higher affinity MAbs CC49 and CC83 versus B72.3 at every dose level. While 500 microCi of B72.3 were required to reduce tumor growth in only a minority of tumor-bearing animals, the use of the same amount or less of the radioimmunoconjugates of CC49 or CC83 resulted in strong antitumor effects in 80 to 100% of tumor-bearing animals. Thus, stronger antitumor effects were seen using as little as 2.5- to 3-fold less of the higher Ka immunoconjugates CC49 and CC83 as compared with B72.3. While we acknowledge the potential disadvantages of higher Ka MAbs in some situations, at least the experimental studies and model system described here show that a distinct therapeutic advantage exists with the use of higher affinity immunoconjugates.  相似文献   
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Background  

Correct diagnosis in psychiatry may be improved by novel diagnostic procedures. Computerized Decision Support Systems (CDSS) are suggested to be able to improve diagnostic procedures, but some studies indicate possible problems. Therefore, it could be important to investigate CDSS systems with regard to their feasibility to improve diagnostic procedures as well as to save time.  相似文献   
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Strategies for controlling cat fleas, Ctenocephalidesfelisfelis (Bouché), have undergone dramatic changes in the past 5 yr. With the advent of on-animal treatments with residual activity the potential for the development of insecticide resistance increases. A larval bioassay was developed to determine the baseline susceptibility of field-collected strains of cat fleas to imidacloprid. All four laboratory strains tested showed a similar level of susceptibility to imidacloprid. Advantages of this bioassay are that smaller numbers of fleas are required because flea eggs are collected for the test. Insect growth regulators and other novel insecticides can also be evaluated. Using a discriminating dose, the detection of reduced susceptibility in field strains can be determined with as few as 40 eggs.  相似文献   
8.
Kosaki overgrowth syndrome is a recently described syndrome characterized by distinctive facial features, brain white matter lesions, and developmental delay. Germline activating heterozygous PDGFRB mutations have been reported in this condition. Systemic connective tissue‐type findings have been described in some individuals. We describe a 19‐year‐old Caucasian female with a history of hydrocephalus, Dandy–Walker malformation, cervical spine arachnoid cyst, progressive scoliosis, and overgrowth. Her physical exam included distinctive craniofacial dysmorphism, as well as soft and hyperextensible skin. Cardiovascular imaging during adolescence revealed saccular aneurysms in both coronary artery systems and subtle tortuosity of the cervical vertebral arteries. Exome sequencing trio analysis identified a de novo previously reported pathogenic variant in PDGFRB, c.1696T>C (p.[Trp566Arg]). Further functional studies included platelet‐derived growth factor cellular metabolic pathway activity that confirmed the variant causes a constitutive activation of the PI3K‐AKT pathway. This is the first report to characterize the activating nature of this PDGFRB variant. We also highlight the connective tissue findings seen in Kosaki overgrowth syndrome and recommend baseline echocardiographic evaluation in all individuals with this condition with particular emphasis on coronary arteries.  相似文献   
9.
Stress and disease: the concept after 50 years   总被引:1,自引:0,他引:1  
Although there is no generally accepted definition of 'a state of stress' in biological or social systems, biologists and social and behavioral scientists continue to use the term. They communicate meaningfully by describing and measuring sources of stress and their observed effects on living organisms, without attempting to define the intervening variables. Biologists and medical scientists tend to be concerned with sources of stress that are concrete and observable, and can otherwise be considered as 'causes' of illness and injury; social and behavioral sciences tend to be concerned with sources of stress that represent information that arises from outside the person and is mediated by higher centers of the central nervous system. It is clear that such "psychological stresses" can lead to alterations of internal functions down to the biochemical level, and that they are potential 'causes' of disease; but they do not usually act independently of other mechanisms. The central thesis of the stress theory of disease, as elaborated by Cannon and Selye, appears to have been thoroughly established. Disease can be regarded as a phenomenon that occurs when an agent or condition threatens to destroy the dynamic steady state upon which the integrity of the organism depends; and the manifestations of disease appear to be, in large measure, manifestations of the organism's efforts to adapt to, and to contain, threats to its integrity. In this sense, all diseases are to some extent disorders of adaptation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Cystic hypersecretory carcinoma (CHC) is a rare variant of intraductal carcinoma. A CHC in a 50-year-old woman was excised and processed for light and electron microscopy and immunohistochemistry. The tumor had a marked cystic appearance. The walls of the cysts consisted of epithelial and myoepithelial cells and a well-developed basement membrane. The epithelial cells contained well-developed rough-surfaced endoplasmatic reticulum and Golgi apparatus. Secretory granules were not detected, with the exception of a few mucus-producing cells. The secretion was predominantly homogenous, reminiscent of thyroid colloid, and demonstrated distinct PAS positivity. The cells displayed a strong labeling with epithelial membrane antigen (EMA) and EMA-positive structures were observed within the intraluminal secretion, too. Some of these were stained by alcian blue. In addition, the colloid-like material was admixed with mucus showing a filamentous internal structure and lipid droplets resulting in some heterogenity of the secretion. Intraductal micropapillary proliferation in some of the cysts and adjacent nondistended ducts was a further defining feature of the tumor. Steroid hormone receptor and Ki-67 proliferation marker immuno his Tochemistry showed scattered positivity among the tumor cells. These results are in agreement with previous observations and further clarify the nature of this low-grade in situ cancer.  相似文献   
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