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951.
This paper describes the morphology and phylogenetic significance of a well-preserved fossil human cranium found near Reilingen, Germany in 1978. The specimen consists of two complete parietals, most of the right temporal, and 70% of the occipital. The specimen displays several features characteristic of early "archaic" Homo sapiens: maximum breadth at the supramastoid crests, roughly pentagonal occipital view, an angular torus, superoinferiorly elongate/ anteroposterior shortened squamous temporal, strong mastoid, and separation of the tympanic and mastoid temporal portions. Other features align the Reilingen cranium with the "classic" Neandertals: developed suprainiac fossa, bilaterally protuberant occipital torus, strong juxtamastoid eminence, a highly convex occipital plane, and lambdoid flattening. This morphology and our cephalometric analysis support the assignment of this specimen to a Stage 2 "pre-Neandertal" group (e.g., Steinheim, Swanscombe, and Atapuerca [SH site]). Following an "Accretion Model" of European hominid evolution, Stage 2 succeeds Stage 1 European "early-pre-Neandertals" (e.g., Mauer and Petralona), and precedes both the Saale-Eem Stage 3 "early Neandertals" (e.g., Biache 1), which present greater platycephaly, a reduced mastoid process, an enlarged juxtamastoid eminence, and true "en-bombe" (parieto-occipital form), and Weichsel Stage 4 "Neandertals" (sensu stricto, i.e., "classic" Neandertals). 相似文献
952.
Alpha-L-fucose is a 6-carbon deoxyhexose that is commonly incorporated into human glycoproteins and glycolipids. It is found at the terminal or preterminal positions of many cell-surface oligosaccharide ligands that mediate cell-recognition and adhesion-signaling pathways. These include such normal events as early embryologic development and blood group recognition and pathologic processes including inflammation, infectious disease recognition, and neoplastic progression. Fucosylated oligosaccharide ligands mediate cell-cell adhesion through binding to cell-surface selectins (calcium-dependent binding proteins) and calcium-dependent interactions with other cell-surface carbohydrate counterligands. A number of fucose-containing "natural ligands" are common to inflammatory and malignant cell processes. We review evidence that alpha-L-fucose is critically important for cell-cell and cell-matrix adhesion in a variety of normal and pathologic processes, particularly neoplasia. Current results suggest that alpha-L-fucose provides the essential structure that enables carbohydrate ligands to bind to selectins and to carbohydrate counterligands and thereby alter cellular homeostasis. 相似文献
953.
The hyperventilation syndrome (HVS), characterised by multiple somatic symptoms induced by inappropriate hyperventilation, constitutes the physiopathological manifestation of a common disorder in general medicine. As a synonym of spasmophilia or tetany, it has the advantage of offering diagnostic criteria, even though the latter are still vaguely defined. But its definition allows for objective measurements: indeed, a decrease in PCO2 during a hyperventilation provoking test and an abnormally low PCO2 rate at rest can be easily quantified. Moreover, the HVS concept offers a treatment which is both structured (respiratory reeducation, psychotherapy and pharmacology) and efficient. Yet, a number of scientific uncertainties still exist. There is no general agreement regarding the criteria which should be taken into account in a hyperventilation provoking test in order to diagnose an hyperventilation syndrome; the specificity of such a test is weak and a placebo can induce as many symptoms as can a HVS. Respiratory reeducation has good results but does not necessarily have an effect on PCO2. Some therapists see in it no more than a mechanism of relaxation and a rational explanation of frightening symptoms. This has led some authors to reject the term "hyperventilation syndrome" and to prefer the expression "chronic hyperventilation of unknown origin". 相似文献
954.
The authors describe a case of traumatic retinal dialysis with retinal detachment from a water balloon slingshot during a "water balloon war." A 31-year-old woman presented with decreased visual acuity in her right eye 2 days after being hit by a water balloon. The visual acuity in the right eye was counting fingers and fundus examination showed subtotal retinal detachment secondary to a superonasal dialysis. The patient underwent a scleral buckling procedure with external drainage, and at 18 months visual acuity was stable at 20/50 with attached retina. Water balloon eye injuries can result in permanent visual loss. More public awareness needs to be created regarding the potential harmful effects of this commonly used "toy." 相似文献
955.
JJ Body 《Canadian Metallurgical Quarterly》1998,19(4):A309-A311
Supportive care is defined as the totality of medical, nursing, psychosocial and rehabilitative support from the onset of the disease until possible fatal outcome, including all active therapeutic phases. This concept is thus quite large and heterogeneous. The term palliative care is reserved for the approach to the terminal patient. Hospital "Palliative Medicine" should be considered as a subspecialty of Internal Medicine and Medical Oncology. In palliative medicine, symptom control, and no longer prolongation of survival, takes a preponderant place to finally become the only goal to reach. In our mind, a Palliative Care Unit is not necessarily the final stay of a patient where spiritual support will be preponderant. One of our essential goals is always that the patient can come back in his family in collaboration with the family doctor, even for a short time. The ideal situation consists in short stays in the Unit to treat an acute complication before the patient is sent back home or to his Residency. Along this line, a very close collaboration with the family doctor is absolutely essential. 相似文献
956.
957.
RP Dirks ST Van Genesen JJ KrUse L Jorissen NH Lubsen 《Canadian Metallurgical Quarterly》1998,66(2):267-269
A pregnant patient at 38 weeks' gestation developed symptoms of local anaesthetic toxicity following intravenous regional anaesthesia (IVRA) for hand surgery, using a standard dose of lignocaine. Reports suggest that a number of factors, both physiological and pharmacological, combine to increase the likelihood of local anaesthetic (LA) toxicity in pregnancy despite employment of a conventional "safe" IVRA technique. It is suggested that for IVRA, pregnant patients are premedicated with a benzodiazepine, the tourniquet time is increased and the concentration of LA is decreased to reduce the risks of LA toxicity. 相似文献
958.
Alexandra?SouchetEmail author Julien?Fontaine Michel?Belin Thierry?Le Mogne Jean-Luc?Loubet Michel?W.?Barsoum 《Tribology Letters》2005,18(3):341-352
We report here on the friction behavior of fine- and coarse-grained Ti3SiC2 against steel and Si3N4 balls. Two successive friction regimes have been identified for both grain sizes and both counterparts. First, Type I regime is characterized by a relatively low (0.1–0.15) friction coefficient, and very little wear. Sliding occurs between a tribofilm on the ball and the Ti3SiC2 plane when against steel. Then, a Type II regime often follows, with increased friction coefficients (0.4–0.5) and significant wear. Compacted wear debris seems to act as a third body resulting in abrasion of the ball, even in the case of Si3N4. The transition between the two regimes occurs at different times, depending on various factors such as grain size, type of pin, and normal load applied. Some experiments under vacuum showed that the atmosphere plays also a major role. The reason for this evolution is not fully clear at that time, but its understanding is of major technological importance given the unusual good properties of this material. 相似文献
959.
OBJECTIVE: To establish a genetic linkage between highly polymorphic microsatellite loci and the disease locus responsible for an autosomal recessive neurodegenerative syndrome that causes posterior column ataxia and retinitis pigmentosa. BACKGROUND: The authors reported previously a genetic syndrome that causes visual impairment, proprioceptive loss, sensory ataxia, and areflexia in affected individuals from a large, inbred family belonging to a sectarian population that has been genetically semi-isolated from mainstream society for several centuries. METHODS: To find the disease locus responsible for this condition, the authors performed a genome-wide search using genetic loci spaced at 10 to 20-cM intervals spanning human chromosomes (chr) 1-22. Pairwise linkage analysis, multipoint linkage analysis, and haplotype reconstruction were used to delineate the candidate region containing the disease gene. RESULTS: After testing 226 loci that covered the entire genome, the authors identified a maximum lod score of 8.94 at a recombination fraction of 0.00 for locus D1S2692. Additional analyses placed the disease gene, AXPC1, in an 8.3-cM interval flanked by markers D1S2692 and D1S414 on chr 1q31-q32. CONCLUSIONS: This study suggests that a single genetic mutation can cause selective degeneration of the posterior columns of the spinal cord and retina. Finding the gene responsible for this syndrome may increase our understanding of the molecular basis of diseases that affect sensory neurons. 相似文献
960.