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91.
INTRODUCTION: The different occurrence of Suicide depending on the rural/urban environment, as well as the interaction of this variable with others such as sex and age has given rise to a large quantity of investigations over the world. It was necessary to carry out in Spain an updated study of these characteristics. OBJECTIVE AND METHODS: Our purpose is to work with the raw data referred to suicide in the two last Spanish Census years. 4,619 records of suicide are requested and obtained from the Spanish National Statistics Institute registered in the years 1981 and 1991. Adjusted rates by rural/urban environment, sex and age are established and compared to each other. RESULTS AND CONCLUSIONS: Suicide rate in Spain is always higher in the cities that in the country, no matter be sex or the age group. However, there appears to be no continuous relationship between Suicide and the environment variable, since the large cities seem to confer a certain prevention. On the other hand, the feminine urban suicidal behaviour is becoming quantitatively more and more similar to those of men.  相似文献   
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Studies on the pathobiology of chronic (long-term) hepatitis B virus (HBV) infection and in vitro drug testing have been hampered by the lack of appropriate systems for culturing susceptible cells chronically infected with HBV. Most of the in vitro studies of HBV replication have been performed with HBV genome-transduced cell lines. In this system, viral production is mainly the result of chromosomal replication. In an in vitro infection system, owing to medium refreshment (which leads to the removal of infectious particles necessary for the perpetuation of infection) and to trypsinization for cell passages, it is difficult, if not impossible, to maintain chronic HBV infection, despite the use of susceptible cells. To circumvent these unfavourable factors for chronic HBV infection in vitro, we cultured microcarrier-attached immortalized human hepatocytes, infected with HBV, in molecularporous (MW 12,000-14,000) membrane (dialysis) bags for a duration of 2 months. HBV covalently-closed-circular (ccc) DNA, HBV precore/core and X mRNAs were detected in the cells cultured in this system following infection until the end of the experiment (day 58), while in classical culture conditions (monolayer), markers of HBV replication were also detected. Production of hepatitis B surface antigen (HBsAg) and HBV DNA was detected and their levels in culture medium (collected at the end of experiments from the molecularporous membrane bags) were increased 2.86- and 3.28-fold respectively. Using Southern blot analysis, HBV replicative intermediates could also be demonstrated throughout the experiments. However, integrated HBV DNA was not present. In contrast, HBV ccc DNA, HBV precore/core and X mRNAs, and replicative intermediates were not demonstrable in FTO 2B rat hepatoma cells infected in the same manner in parallel experiments. This in vitro infection system, using susceptible, immortalized human hepatocytes, therefore provides a new tool for studying the long-term effect of HBV infection, mainly involving episomal replication in hepatocytes, and for drug testing.  相似文献   
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In this paper, epidemiological distribution and trend on injuries of Chinese population are described, and at the same time, characters and proportion of injuries to the total deaths are analyzed according to data in National Disease Surveillance Point system (DSP). Some important injuries and variance in population by different sexes, age groups and places are analyzed in detail. The death rate on suicide of Chinese population is high, reaching 19.58/10(5). The rate of suicide among females is higher than males, especially in female population of 20-34 age group, proportion is 46.70% to female total suicide. Rate of suicide of old people is also very high, population of over 60 years olds. It counts 29.72% to the total. The death rate due to transportation is going up, from 9.82/10(5) in 1991 to 14.32/10(5) in 1995, with an annual average incseasing ratio 7.84%. Drowning is the major cause of injuries for children of 0-14 years old, proportion of their death is 56.56% to the total death of drowning, 46.48% among them is children of 1-4 years old.  相似文献   
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Glucagon-like peptide 2 (GLP-2) is a 33-aa proglucagon-derived peptide produced by intestinal enteroendocrine cells. GLP-2 stimulates intestinal growth and up-regulates villus height in the small intestine, concomitant with increased crypt cell proliferation and decreased enterocyte apoptosis. Moreover, GLP-2 prevents intestinal hypoplasia resulting from total parenteral nutrition. However, the mechanism underlying these actions has remained unclear. Here we report the cloning and characterization of cDNAs encoding rat and human GLP-2 receptors (GLP-2R), a G protein-coupled receptor superfamily member expressed in the gut and closely related to the glucagon and GLP-1 receptors. The human GLP-2R gene maps to chromosome 17p13.3. Cells expressing the GLP-2R responded to GLP-2, but not GLP-1 or related peptides, with increased cAMP production (EC50 = 0.58 nM) and displayed saturable high-affinity radioligand binding (Kd = 0.57 nM), which could be displaced by synthetic rat GLP-2 (Ki = 0.06 nM). GLP-2 analogs that activated GLP-2R signal transduction in vitro displayed intestinotrophic activity in vivo. These results strongly suggest that GLP-2, like glucagon and GLP-1, exerts its actions through a distinct and specific novel receptor expressed in its principal target tissue, the gastrointestinal tract.  相似文献   
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Preclinical studies were designed to investigate the feasibility and safety of recombinant adenoviruses transduced into the hepatic artery of nonhuman primates. The vectors used are recombinant adenoviruses deleted in E1 and contain either a temperature-sensitive mutation in the E2a gene, which encodes a defective DNA-binding protein at nonpermissive temperatures, or a deletion of the E4 region, including open reading frame (ORF) 6. Six 8- to 10-kg baboons underwent femoral artery cannulation, and angiographic techniques were used to introduce vector selectively into either a portion of the right lobe of the liver via a branch of the right hepatic artery or the common hepatic artery. Necropsies were performed at 4, 29, or 61 days. Serial sequential liver biopsies were performed in the baboons that survived 29 or 61 days. In the 2 baboons with vector transduction into the right hepatic artery, X-Gal histochemical analysis of the liver showed evidence of quantitatively increased gene transfer in the targeted lobe; however, gene transfer was present throughout the liver. Quantitative analysis of histopathology showed that portal inflammation was present throughout both livers transduced with the highest dose of vector. No differences were seen in the level of portal inflammation in targeted and untargeted lobes despite the observed qualitative and quantitative differences in gene expression. Southern blot analysis of total cellular DNA isolated from targeted and nontargeted lobes showed similar levels of viral DNA throughout the liver. Polymerase chain reaction (PCR) analysis was able to detect viral DNA sequence in gonads and brain as well as many other tissues in baboons treated with high-dose vector. In baboons treated with lower doses of an E1-E4 deleted vector expressing the human ornithine transcarbamylase (OTC) gene, DNA was detectable by nested PCR in liver but not gonads at days 29 and 61. The data suggest that intraarterial administration of recombinant adenoviral E1-E4 deleted vector is feasible and safe. At high doses of vector, widespread dissemination of vector DNA is seen. At low doses, hepatic gene transfer is not associated with vector DNA dissemination to gonads.  相似文献   
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Patients with disabling, persistent somatization pose significant challenges in clinical management. This study describes 92 patients treated on an inpatient psychosomatic medicine unit for persistent somatization. The most important factor in defining clinically significant subgroups of these patients was mood. Compared with depressed somatizing patients, nondepressed somatizing patients had chronic illnesses of early onset, had symptoms that were not correlated with current life stressors, and were generally unresponsive to treatment. There were few clinical predictors of treatment outcome apart from the duration of symptoms, the presence of mood disturbance, and a history of stable interpersonal relationships.  相似文献   
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