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21.
J. Román Corona-Rivera Alfredo Corona-Rivera Sylvia E. Totsuka-Sutto Enrique Corona-Rivera 《Clinical genetics》1997,51(4):257-259
Gluteal and lower extremity hypoplasia with ipsilateral toe brachysyndactyly were noted in a 23-year-old woman similarly affected to the only previously reported case of the lower extremity counterpart of Poland sequence. Since no neurological deficit was found, and electromyographic and nerve conduction studies in the affected limb were normal, we propose a vascular origin which would involve the external iliac artery supply analogous to the subclavian artery supply disruption in the upper extremity Poland sequence. 相似文献
22.
Use of the Honan balloon as a compression device for intravitreal triamcinolone acetonide injection.
Obtaining a lower intraocular pressure (IOP) before an intravitreal injection is important to avoid the danger of an immediate increase in IOP. This article describes the use of the Honan balloon to reduce the IOP before an intravitreal triamcinolone acetonide injection instead of the other procedures described in the literature, which may increase the risk of complications. The results of the technique in 19 patients with retinal vein occlusion are reported. Honan balloon was applied at 30 mm Hg for 10 minutes and the injection was then performed no more than 5 minutes after the removal of the Honan balloon. In no more than 10 minutes, this procedure resulted in a significant reduction in IOP. No complications such as central retinal artery occlusion were observed after the injection. 相似文献
23.
Enrique Barbieri 《Optimal control applications & methods.》1994,15(1):35-48
The two-stage synthesis of a multi-input/multi-output optimal proportional-integral (PI) controller is described for linear, time-invariant systems. In the first stage the PI controller is designed by solving a steady state algebraic Riccati equation. As a result, the optimal cost is expressed in terms of the system's constant output set-points. In the second stage the cost is further reduced by optimally selecting the output set-points to minimize a static quadratic performance index subject to linear algebraic constraints. The design framework is applied to a planar redundant robotic manipulator equipped with four joints and mounted at the tip of a long flexible arm. We then address the problem of self-motion control in the presence of vibratory disturbances. 相似文献
24.
25.
Salivary dermal analogue tumors arising in lymph nodes 总被引:3,自引:0,他引:3
Dermal analogue tumor, an unusual type of monomorphic salivary adenoma, occurs in the parotid gland and rarely in other salivary tissues. This report describes three patients with dermal analogue tumors arising from ectopic salivary tissue in lymph nodes. Two tumors appeared in the periparotid lymph nodes and one in the lateral upper cervical region. All of the patients were men, aged 50 to 60 years, who all had a painless neck mass for 1 year or longer. Currently, the patients are free of disease 14, 3, and 2 years, respectively, after surgical excision. Dermal analogue monomorphic adenomas join several other salivary tumors in possible intranodal origin and should not be confused with metastases. 相似文献
26.
Francisco Camacho Juan Ferrando Antonio R. Pichardo Ismael Sotillo Enrique Jorquera 《Pediatric dermatology》1993,10(1):54-57
Abstract: A 20-year-old woman and her 12-year-old brother had hypohidrotic ectodermal dysplasia, cleft lip and palate, midfacial hypoplasia with narrow nose from the nasal bridge to the tip, narrow dysplastic nails, and conical teeth and hypodontia, and hypospadias and hypoplastic uvula in the boy. The woman had major underdevelopment of intellectual capacity. The most important hair anomalies in both siblings were sparse eyebrows, pili torti, and pili canaliculi. Some of the pili canaliculi had two canals (pili bicanaliculi), and the cross section for scanning electron microscopy had a quadrangular aspect. This is the seventh family reported with Rapp-Hodgkin ectodermal dysplasia. 相似文献
27.
Studies on the mechanism of 3-deazaguanine cytotoxicity in L1210-sensitive and -resistant cell lines
Summary 3-Deazaguanine (3-DG), a purine analogue, has unusual antitumor activity against experimental mammary tumor models and a number of other solid tumors. Others have shown that mutant CHO cells deficient in hypoxanthine guanine phosphoribosyl transferase (HGPRTase) or adenine phosphoribosyl transferase (APRTase) are resistant to 3-DG. We developed a L1210 cell line resistant to 3-DG, L1210/3-DG, by subculturing the parent L1210/0 cells in the presence of increasing concentrations of 3-DG. The IC50 was 3.5 M and 620 M for L1210/0 and L1210/3-DG, respectively. Cytotoxicity studies proved the resistance to be stable. Examination of the baseline-specific activity of HGPRTase and APRTase showed that the former was 118-fold lower in L1210/3-DG than in L1210/0, and the latter demonstrated no difference. A 4-h treatment of the cell lines at IC50 doses showed 48% and 23% reductions in IMP dehydrogenase in L1210/0 and L1210/3-DG, respectively. The rate of de novo purine biosynthesis was studied by using [14C]formic acid. Formate flux increased 2-fold in L1210/3DG in concert with the observed deficiency of HGPRTase in the cell line. 3-DG uptake was studied with [14C]-labelled compound. The total radioactivity was 9-fold higher in L1210/0 than in L1210/3-DG at 2 h. Subsequent chromatographic separation of radioactivity showed the 3-DG and 3-deazaguanosine pools of the drug to be equal in both lines. However, 3-DG nucleotide pools at 1 min and 2 h were 2.5-fold and 16-fold lower, respectively, in L1210/3-DG than in L1210/0. 3-DG incorporation studies with radiolabelled drug demonstrated that 3-deazaguanine is incorporated in the acid-insoluble fraction of the cell. These studies conclude that HGPRTase, and not APRTase, is required for the activation of drug. Inhibition of IMP dehydrogenase is partially responsible for antitumor activity of the drug. The incorporation of drug into nucleic acids may be a major mechanism for its antitumor activity. Further studies using a cloned cDNA probe for hypoxanthine guanine phosphoribosyltransferase (HGPRT) demonstrated no change in the DNA arrangements of the L1210/3-DG cell line, and Northern blot analysis showed approximately equal expression of mRNA in both cell lines.Abbreviations used APRTase
adenine phosphoribosyltransferase
- HGPRTase
Hypoxanthine guanine phosphoribosyltransferase
- IMPD
Inosine mono-phosphate dehydrogenase
- PRPP
5-Phosphorylribose-1-pyrophosphate
- AOPCP
, -Methyleneadenosine 5-diphosphate
- NAD
Nicotineamide dinucleotide
- EDTA
Ethylenediamine tetra acetic acid
Presented at annual meeting of American Association of Cancer Research in May, 1986Supported in part by Warner-Lambert Company, Ann Arbor, Michigan 相似文献
28.
The authors describe the different "retentive complexes" proposed by the Akers, Roach and Ney schools and analyse their biomechanical validity. 相似文献
29.
Emilia Lachica Aurelio Luna Enrique Villanueva 《International journal of legal medicine》1989,103(2):111-119
Summary The diagnosis of myocardial infarction requires the use of a group of tests that are very efficient, quick and inexpensive. Another important consideration is the choice of myocardial sampling zones, especially in cases of differential diagnosis between a cardiac injury secondary to a trauma or violent asphyxia and others, secondary to myocardial infarction. The aim of this work was to choose, through discriminant analysis, the most useful zones of cardiac tissue for the quantification of free fatty acids and free carnitine and for the performance of the K/Na quotient, as biochemical parameters for the postmortem diagnosis of myocardial infarction. According to the discriminant analysis performed, seven zones of cardiac tissue are necessary to achieve a differential diagnosis among myocardial infarction, other natural deaths, and violent deaths with a 71.9% efficacy. Greater diagnostic efficacy was found (78.1%) for differentiating between natural deaths and violent deaths.
Offprint requests to: E. Lachica 相似文献
30.