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91.
Congenital cranial dysinnervation disorders (CCDDs) are responsible for 1–2% of infant strabismus cases. Insufficient innervation and misinnervation of aberrant nerve fibres lead to motility restrictions and synkinesis. We present the most common CCDDs and explain their pathogenesis and the resulting clinical features. Furthermore, we emphasize essential diagnostic steps and treatment aspects.  相似文献   
92.
A 24-year old woman displayed a coloboma of the right optic nerve with multiple small parapapillary retinochoroidal colobomas. This rare association makes one suspect that the pathogenesis of colobomatous defects of the optic disc area are caused by a faulty closure of the embryonic fissure and an abnormal maturation of the cells of the anlage of the optic nerve head.  相似文献   
93.
In a general review, the authors discuss present knowledge on the main protein on the surface of the normal fibroblast, fibronectin. The peculiarities of this glycoprotein (localisation at the level of the cell surface, importance of thiol groups in the structure and expression of certain of its properties, reduction of the cells transformed by oncogenic viruses) are considered. The relationships which they may present with a plasma protein, cold insoluble globulin, are discussed together with the important role which they seem to play in the phenomena of cell adhesiveness.  相似文献   
94.
Poly(oxyethylene)s with dithioster end groups were obtained from mono- and dihydroxyl terminated commercial polymers by reaction with dimethyl chloroacetamide, subsequent thionation of the amide group, and usual conversion of the thioamides into the dithioesters 14, 15 and 20, 21 . The best results were obtained in the syntheses of the S-carboxymethyl dithioesters ( 15 and 21 ). The resulting reactive poly(oxyethylene)s were grafted upon silica tubes and electrophoresis cells, previously activated by aminopropylsilanization. These graftings result in lowering of the surface potential of the tubes and in suppression of the electro-osmosis flow in an electrophoresis cell tested with a TiO2 standard sample.  相似文献   
95.
The effects of castration and of subsequent androgen administration on fiber size were investigated in several frog skeletal muscles. Four months after castration, cross-sectional cell area decreased by 70% and 14%, respectively, in the flexor carpi radialis and flexor carpi centralis muscles of the forearm and only by 2% in the ileo fibularis muscle of the thigh. Injection of testosterone propionate induced a hypertrophic response that reversed the effects of androgen deprivation; after 6 weeks, complete recovery to the control value was observed in all muscles selected. This sensitivity to the exogenous androgen was not altered by denervation; a similar hypertrophic evolution was seen in the denervated right muscles and in the homologous intact left muscles of the forearms. Using the myosin ATPase reaction, the muscle histochemical patterns were unchanged in all conditions tested. These results suggest that (i) a gradient of sensitivity to androgens exists in different frog muscles; (ii) androgens control the myofiber size but not the nerve-muscle organization as can be seen from the myofibrillar ATPase pattern; and (iii) the androgen sensitivity is not dependent on the motor nerve.  相似文献   
96.
The history of prealbumin dates back to the early forties and may be divided into three parts, based on a chronological and functional approach. The first part--the discovery and the identification of prealbumin--was essentially based on classical protein chemistry methods. The second--the demonstration of prealbumin as a thyroid hormone-binding protein (thyroxine-binding prealbumin)--has greatly benefited from isotopic techniques. The third one--establishing prealbumin as a nutritional marker--was a result of field studies on nutrition. The discovery of the role of prealbumin in retinol binding led to a change in its name, prealbumin becoming transthyretin. Finally, structural studies and mutation analysis of transthyretin in patients with amyloid neuropathy have opened a new area of research.  相似文献   
97.
Antibodies against nerve growth factor (NGF) in sera were detected by enzyme-linked immunosorbent assays (ELISA), by their isolation after passage of sera through NGF immunoadsorbent columns and by their specificity to bind and immunoprecipitate mouse NGF as well as to stain by immunohistochemical methods cellular sites of NGF synthesis. Increased levels of anti-NGF antibodies were found in sera of herpes simplex virus (HSV)-infected patients but not in HSV-inoculated rabbits. As HSV latency is known to be promoted by NGF in vitro, these results may suggest that anti-NGF antibodies modulate the cytokine function of NGF and thus might play a role in HSV infection. The biological function of circulating antibodies against NGF, in general, is now open to future investigation.  相似文献   
98.
The authors assess of three decades of struggle against Bancroftian filariasis in French Polynesia. Wuchereria bancrofti var. pacifica, aperiodic filaria, and Aedes polynesiensis, mosquito with high parasitologic output, set up a cycle very well adapted to the Polynesian environment; after numerous tests, the chemoprophylaxis with diethylcarbamazine (3 mg/kg/half-year) of all the exposed population has been decided, in association with methods of vector-control (use of predatory crustaceans). However, the achievement of this strategy is impeded by economical contingencies and the endemic comes up again particularly in areas close to eradication. Entomological clues show a high transmission over the greater part of French Polynesia.  相似文献   
99.
Twenty four patients who were hospitalized for a suspicion of spondylodiscitis were prospectively evaluated with magnetic resonance imaging (MRI), radiology and radionuclide studies. Fifteen patients had an infectious spondylodiscitis, four had a vertebral degenerative disease, four had a rheumaticus spondylodiscitis, one had a chemical spondylodiscitis. The microbiological examinations and the clinical development bore the diagnosis out. Seven patients underwent Indium 111 scanning. The results of this scanning were correlated with MRI results. The MRI was performed with a 0.35 T whole body superconducting unit using spin echo technique. All patients were studied in the sagittal plane with two pulse sequences and more often with a surface-coil: TR 500 msec./TE 28 msec. and TR 2,000 msec./TE 60 msec. In all cases of true infectious spondylodiscitis the MRI results finding were characteristics. On the image obtained with the TR 500 msec./TE 28 msec., there was a confluent decreased signal intensity from the vertebral bodies and the intervertebral disk space. On the image obtained with TR 2,000 msec./TE 60 msec. there was an increased signal intensity from the vertebral bodies and the intervertebral disk space. The other spondylodiscitis have given a different MRI imaging, it was a confluent decreased signal intensity from the vertebral bodies and the intervertebral disk space on the twice pulse sequences. different images were obtained during the evolution of the infectious: first we observed a modification of the vertebral signal then the typical image that we described then a normal signal of the vertebral bodies with a pathological signal from the intervertebral disk space at last a degenerative intervertebral disk.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
100.
5-Fluorouracil, 5-fluorouridine (FUrd), 5-fluoro-2'-deoxyuridine (FdUrd), 5-fluorocytidine (FCyd), 5-fluoro-2'-deoxycytidine (FdCyd), 5-trifluoro-2'-deoxythymidine (F3dThd), and the 5'-monophosphates and 3',5'-cyclic monophosphates thereof were found to inhibit thymidine kinase-deficient (TK-) mutant strains of herpes simplex virus (HSV) at a much lower concentration than the wild-type (TK+) HSV strains. Other 5-substituted 2'-deoxyuridines that have previously been recognized as potent thymidylate synthase inhibitors behaved in a similar fashion. The activity of FdUrd, FdCyd, F3dThd, and their 3',5'-cyclic monophosphates against TK-HSV was readily reversed by 2'-deoxythymidine (dThd) but not by 2'-deoxyuridine (dUrd). These compounds also inhibited the incorporation of [6-3H]dUrd into DNA at a concentration which was up to 5 orders of magnitude lower than the concentration at which the incorporation of [methyl-3H] dThd was inhibited. Thus, while not being a target for the well established anti-HSV compounds in TK+HSV-infected cells, thymidylate synthase appears to be an important target in TK-HSV-infected cells. In addition to dTMP synthase, TK-HSV-infected cells appear to reveal other therapeutically exploitable targets such as OMP decarboxylase (towards pyrazofurin), CTP synthase (towards carbodine and its cyclopentenyl analogue), dihydrofolate reductase (towards methotrexate), and S-adenosylhomocysteine hydrolase (towards neplanocins).  相似文献   
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