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BACKGROUND: Blood requirements for Head and Neck surgical procedures have not been studied carefully. In order to set up an autotransfusion program, the blood loss and transfusion requirements should be known precisely. METHODS: The blood bank database was used to determine which Head and Neck procedures required blood transfusion during the previous 5 years. A list of 10 transfusion-associated operations was established, the records of all patients who underwent these procedures during a 5-year period were reviewed, and average the blood loss and number of units transfused determined. RESULTS: All procedures were for cancer resection. The operations were classified in 3 groups according to their transfusion probability: high (> 80%), low (< 5%) and moderate. For the moderate transfusion group, age, preoperative hemoglobin, and past medical history of cardiac and pulmonary disease were associated with higher incidence of transfusion. An average delay of 3 weeks was found between the diagnosis and the actual surgery. CONCLUSION: The transfusion requirements of Head and Neck surgical procedures could be safely met by an autotransfusion protocol, given the average delay of 3 weeks between diagnosis and surgery.  相似文献   
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A method for aligning cadaver knee specimens to a mechanical testing rig and determining local anatomical coordinate systems using landmarks identifiable on plane X-rays is introduced. Three sequential rotational alignments arc used to position the femur and tibia relative to the coordinate system of the testing mechanism. To validate this methodology five independent observers aligned the same knee specimen. The maximum error in the alignment orientations of the tibia and femur was 2.2 from the mean. These small misalignments produced variations of up to 4.7 in tibio-femoral rotations measured during knee flexion. Kinematic measurements of 15 specimens aligned using this procedure indicate that knee alignment is reproducible and physiologically relevant.  相似文献   
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An inhibitory neurotransmitter in mature brain, gamma-aminobutyric acid (GABA) also appears to be excitatory early in development. The mechanisms underlying this shift are not well understood. In vitro studies have suggested that Na-K-Cl cotransport may have a role in modulating immature neuronal and oligodendrocyte responses to the neurotransmitter GABA. An in vivo developmental study would test this view. Therefore, we examined the expression of the BSC2 isoform of the Na-K-2Cl cotransporter in the postnatal developing rat brain. A comparison of sections from developing rat brains by in situ hybridization revealed a well-delineated temporal and spatial pattern of first increasing and then diminishing cotransporter expression. Na-K-2Cl mRNA expression in the cerebral cortex and hippocampus was highest in the first week of postnatal life and then diminished from postnatal day (PND) 14 to adult. Cotransporter signal in white-matter tracts of the cerebrum, cerebellum, peaked at PND 14. Expression was detected in cerebellar progenitor cells of the external granular layer, in internal granular layer cells at least as early as PND 7, and in Purkinje cells beginning at PND 14. Double-labeling immunofluorescence of brain sections with anti-BSC2 antibody and cell type-specific antibodies confirmed expression of the cotransporter gene product in neurons and oligodendrocytes in the white matter in a pattern similar to that determined by in situ hybridization. The temporal pattern of expression of the Na-K-2Cl cotransporter in the postnatal rat brain supports the hypothesis that the cotransporter is the mechanism of intracellular Cl- accumulation in immature neurons and oligodendrocytes.  相似文献   
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We analyzed somatic mutation and loss of heterozygosity (LOH) in the serine/threonine kinase 11 (STK11)/Peutz-Jeghers syndrome gene in 49 colorectal tumors in three different stages of a dysplasia-carcinoma sequence. We detected LOH in 10 of 19 (52.6%) informative colorectal cancers at loci D19S886 and/or D19S883, but no LOH was observed in 25 informative adenomas. We detected a total of 9 somatic mutations [7 of 13 (53.8%) left-sided colon cancers and 2 of 7 (28.6%) left-sided adenomas with high-grade dysplasia], but no mutations were detected in right-sided colon tumors. Of the nine mutations, one was a frameshift mutation (the same mutation detected in Peutz-Jeghers syndrome family previously), and the other eight were missense mutations. This results indicate that STK11 is a tumor suppressor gene and that genetic changes of STK11 play an important role in left-sided colon cancer carcinogenesis.  相似文献   
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OBJECTIVE: The aim of this study is to compare patients with schizophrenia with their relatives and the general public in their attitudes towards schizophrenic psychotic symptoms. METHOD: We used a case vignette depicting a person with typical schizophrenic psychotic symptoms and compared the attitudes of 44 inpatients and 47 outpatients with schizophrenia, 48 of their relatives and 43 members of the general public. We also compared the attitudes of patients with schizophrenia to their own symptoms and the symptoms described in the vignette. RESULTS: Subjects from the general public tended not to recognise psychotic symptoms as features of mental illness and tended not to consider drug treatment and hospitalisation as required. Sex, education level as well as previous contact with the mentally ill were found to be significant determinants of attitude. The levels of symptom awareness in patients with schizophrenia and their relatives are higher but still relatively low. In addition, we found that patients with schizophrenia who correctly appraised psychotic symptoms in another person were also aware of their own mental symptoms and need of treatment. CONCLUSIONS: The level of recognition of psychotic symptoms and awareness of a need for treatment are low in the general public, as well as in patients with schizophrenia and their relatives. These findings are discussed in relation to the assessment of insight in patients and a need for psychoeducational programs for each group.  相似文献   
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The purpose of this study was to determine the Hgb response to a therapeutic trial of iron in infants with anemia compared to those with low-normal hemoglobin values. Hgb was determined in 1.128 one-year-old infants. The 278 infants (25%) who had an Hgb less than 11.5 gm/dl were given a three-month oral course of ferrous sulfate (3 mg iron/kg/day); the regimen was satisfactorily completed by 188 infants. Of the 75 infants whose initial capillary Hgb was in the anemic range (Hgb less than 11.0 gm/dl), 45% had an increase in venous Hgb greater than or equal to 1.0 gm/dl. Of the 113 infants with initial capillary values in the low-normal range (11.0 to 11.4 gm/dl), 28% had greater than or equal to 1.0 gm/dl Hgb response. Despite the lower rate of response in the low-normal group, almost half of the infants with a greater than or equal to 1 gm/dl response would have been missed by using the generally accepted cutoff value of 11 gm/dl for a therapeutic trial. Because of the low cost and simplicity of a therapeutic trial, we favor including the low-normal Hgb group for a therapeutic trial of iron in order to avoid missing iron-responsive individuals among groups of infants with a similarly high prevalence of iron deficiency anemia.  相似文献   
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Dialkyl phosphites react with acenaphthenequinone 1 and aceanthrenequinone 2 to give the respective α-hydroxyphosphonates 3a – c and 5a – c . Structural reasonings, based on chemical reactions and spectral data, are presented.  相似文献   
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