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1.
2400-year solar cycle ascertained by us in the long-term series of various natural characteristics (e.g. the radiocarbon content in samples of well-known ages, oscillations of the sea and ocean levels etc.) includes three parts roughly equal in duration: a phase of high activity, a phase of depression and a phase of moderate activity. In climate oscillations, which are connected with this cycle, the next phenomena are established: a little climatic optimum, a little Ice Age, and a temperate climate epoch.  相似文献   
2.
Jet injection can be used to introduce genes into the cells of differentiated tissues of living animals and organ cultures. When a solution of plasmid DNA is jet injected into a selected tissue or organ, cells lying in or near the path of the jet injection are transfected with the DNA and the introduced gene(s) are expressed. Since there is minimal morbidity from each jet injection, multiple injections can be performed at the same or nearby sites. Both mRNA and protein expression from transfected genes can be quantitated using standard methods. In addition, the technique is an efficient means of DNA immunization. Methodology for using jet injection to transfer plasmid DNA into the cells of skin, fat, mammary gland, and muscle are described.  相似文献   
3.
The results of clinical and laboratory studies on the use of augmentin in severe purulent complications after neurosurgical operations are presented. The laboratory studies carried out with the use of an automatic system Cobas Bact (Roch) showed that the numbers of the augmentin resistant strains of Staphylococcus and Enterobacteriaceae among the pathogens were 47 and an average of 64.5%, respectively. Gram-negative bacteria resistant to augmentin were 1.5 to 2 times less frequent than those resistant to amoxycillin. Still, they were much more frequent than those resistant to cefotaxime and ceftriaxone. Clinical efficacy of augmentin was studied in treatment of 39 patients with various affections of the brain such as tumors, trauma, vascular malformations and inflammatory processes. The postoperative complications were represented by meningitis, pneumonia, sepsis and their associations. The use of augmentin in the severe intra- and extracranial complications was favourable in 82.1% of the cases.  相似文献   
4.
Hemostasis of 100 patients with severe diphtheria infection was studied throughout the disease. The patients were found to have marked procoagulant, anticoagulant and fibrinolytic disorders. Antithrombogenic activity of the vascular wall was also abnormal. The above impairments correlated with the symptoms severity and are interpreted as DIC syndrome which ran subclinically or as hemorrhagic syndrome. The majority of the patients underwent a hyperhypocoagulant phase of DIC syndrome.  相似文献   
5.
BACKGROUND: This study examined the results of surgical treatment of leiomyosarcoma of the esophagus. METHODS: Between January 1920 and December 1996, 17 patients (9 men and 8 women) with leiomyosarcoma of the esophagus were treated surgically at the Mayo Clinic. Median age was 58 years and ranged from 26 to 76 years. Symptoms included dysphagia in 11 patients (64.7%) and odynophagia in 6 (35.3%). The tumor was located in the middle third of the esophagus in 10 patients (58.8%) and in the cervical esophagus in 7 (41.2%). Procedures performed included esophagogastrectomy in 9 patients (Ivor Lewis in 5, left thoracoabdominal in 3, and transhiatal in 1), enucleation in 3, transgastric excision in 1, and exploration without resection in 4. RESULTS: The procedure was considered curative in 11 patients (64.7%). There was one operative death (mortality, 5.9%). Complications occurred in 3 patients (17.6%) and included anastomotic leak in 2 and bleeding requiring reoperation in 1. Growth pattern was infiltrating in 7, polypoid in 5, and intramural in 5. Histologically, the tumor was grade 1 in 6 patients, grade 2 in 2, grade 3 in 7, and grade 4 in 2. The tumor was postsurgically classified as stage I in 2 patients, stage IIA in 7, stage IIB in 1, stage IIIA in 5, stage IV in 1, and unknown in 1. Six patients (35.3%) received adjuvant treatment. Follow-up was complete in 16 patients (94.1%) and ranged from 1 to 182 months (median, 48 months). Five- and 10-year actuarial survivals were 47.0% and 31.0%, respectively. Seven patients (41.2%) are currently alive (median survival, 72 months); all underwent curative resection. Factors affecting survival included completeness of resection, growth pattern, postsurgical stage, tumor grade, and tumor location (p < 0.05). CONCLUSIONS: We conclude that leiomyosarcoma of the esophagus is rare. Complete resection provides long-term survival.  相似文献   
6.
OBJECTIVE: To determine whether maintenance therapy can be discontinued safety in patients with quiescent cytomegalovirus retinitis (CMVR) and increased CD4+ counts after treatment with highly active antiretroviral therapy (HAART). DESIGN: A prospective observational case series. PARTICIPANTS: Eight human immunodeficiency virus (HIV)-positive patients with quiescent CMVR who were taking HAART and had CD4+ counts above 100 cells/microliter elected to discontinue anti-CMV maintenance treatment. INTERVENTION: Biweekly-to-monthly indirect ophthalmoscopy and fundus photographs, monthly-to-quarterly CD4+ counts, and quarterly HIV viral loads were ordered. MAIN OUTCOME MEASURES: Twelve previously affected eyes were examined for evidence of recurrent retinitis, which was defined as any retinal whitening, border opacification, or expansion of areas of retinal pigment epithelial (RPE) atrophy greater than 750 microns. Four previously unaffected fellow eyes were observed for new CMVR. RESULTS: There was no reactivation or progression of retinitis in any patient during the mean follow-up interval of 11.4 months (range, 3-16 months). No previously unaffected eye developed CMVR. CD4+ remained elevated in all patients (range, 70-725; mean, 255). The HIV viral load ranged from undetectable to 139,000 copies. CONCLUSION: Discontinuation of maintenance therapy may be considered in patients with HAART-induced elevated CD4+ counts above 100 cells/microliter, prolonged relapse-free intervals during the reconstitution period before CD4+ counts rise above 100 cells/microliter, and completely quiescent retinitis characterized by RPE scarring only. Reduced risks of drug toxicity and drug-resistant organisms are potential benefits. Close observation for evidence of recurrent retinitis is indicated.  相似文献   
7.
Overview of Fine-Scale Piezoelectric Ceramic/Polymer Composite Processing   总被引:2,自引:0,他引:2  
In the past two decades, piezoelectric ceramic/polymer composites with different connectivities have been developed for transducer applications such as hydrophones, biomedical imaging, nondestructive testing, and air imaging. Recently, much attention has been given to fine-scale piezoelectric ceramic/polymer composites. These composites allow higher operating frequencies, and thus increased resolution, in medical imaging transducers. In this review, methods for processing fine-scale piezoelectric ceramic/polymer composites are discussed. The current capabilities, strengths, and weaknesses of each method are compared. The importance of spatial scale in composite performance is also reviewed. Several of the processing methods have demonstrated composites with fine-scale ceramic phases (<50 μm), and others have potential to form composites with a ceramic scale of under 20 μm.  相似文献   
8.
The anodic behaviour of copper was investigated in ethanol solution containing LiClO4, LiCl electrolyte and water. The type of electrolyte and the water content influences the mechanism of the anodic process and the formation of anodic products. In LiClO4 electrolyte the dissolution of copper is related to the oxidation of Cu(I) to Cu(II). In solutions of LiCl the etching of copper begins with the creation of soluble complexes of Cu(I) with chloride ions and solvent molecules. At potentials above 0.4 V the formation of alkoxides was observed in both solutions, characterized by a yellow tint. On the other hand, above 0.8 V (i.e. above the equilibrium potential of alcohol oxidation) copper dissolution is accompanied by the formation of a blue colloidal suspension of Cu (II) copper salt. Anodic etching of copper in solutions containing 3% H2O at potentials higher than 0.4 V leads to the formation of colloidal suspension of copper oxide nanoparticles.  相似文献   
9.
We describe the origins of fuzzy-trace theory, including Piagetian, interference, information-processing, and judgment and decision-making influences. The contrasting properties of gist and verbatim memory serve as its foundation and, in recent models of spontaneous and implanted false memories, explain seemingly contradictory developmental trends, such as reverse developmental findings, differential time courses for true and false memories, and conflicting effects of trace strength. However, approaches that integrate fuzzy-trace theory with neurological, social, emotional, and motivational perspectives are needed. A method for accomplishing this integration, using the recent models, is introduced and new research that spans these perspectives is discussed. Relations to other contemporary theories, especially source-monitoring and dual-process theories, are also explained. We conclude by rejecting the notion that spontaneous false memories are actually "true" and distinguish gist and verbatim senses of the term "true" that have different consequences in real life.  相似文献   
10.
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