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891.
AG Gon?alves LC Campos TA Gomes J Rodrigues V Sperandio TS Whittam LR Trabulsi 《Canadian Metallurgical Quarterly》1997,65(6):2034-2040
A total of 110 Escherichia coli strains of serogroup O119 were examined for the presence of virulence properties characteristic of enteropathogenic E. coli (EPEC). Three virulence patterns were distinguished based on the detection of a chromosomal gene mediating intimate attachment (eaeA) and plasmid DNA involved in localized adherence (EAF and bfpA). The first pattern, represented by strains which hybridized with three gene probes, was the most common (68%) and, with a single exception, included only O119:H6 strains. Of these strains, 90% showed a typical localized adherence (LA) pattern in HEp-2 cells and 96% were positive for intimate attachment in a fluorescent-actin staining test with a 3-h incubation period. The second pattern was represented by strains which hybridized with the eaeA gene only. Most (89.5%) of these strains showed the LA phenotype but only after 6 h of incubation (LA-like phenotype). The third pattern consisted of strains which were positive for eaeA and bfpA but did not hybridize with the EAF probe. Most (80%) of these strains exhibited the LA-like phenotype. Analysis of several eaeA+ bfpA+ strains for the expression of the pilin subunit (BfpA) of the bundle-forming pili demonstrated that all LA strains expressed BfpA whereas the LA-like strains did not. The study of the clonal relationships, carried out by multilocus enzyme electrophoresis in 79 representative strains, defined 11 distinct electrophoretic types (ETs). ET1 included 66% of the strains, most of which displayed the eaeA+ bfpA+ EAF+ pattern and were serotyped as O119:H6 or O119:H-. The remaining 10 ETs were each represented by no more than five strains and, with the exception of ET8, included strains of a single serotype. The genetic relatedness of the ETs revealed two main clusters, with most strains in cluster A having the eaeA+ bfpA+ EAF+ combination and a O119:H6 serotype. Cluster B was represented by atypical EPEC strains with only the eaeA+ and the eaeA+ bfpA+ virulence pattern. 相似文献
892.
Factors associated with the utilization of traditional Chinese medicine in a small town in Hong Kong
The practice of Traditional Chinese Medicine (TCM) is largely unregulated in Hong Kong. Yet, as previous studies have shown, a sizable segment of the population consults TCM practitioners for health problems. This paper uses health care utilization data from a telephone health survey of 847 adult subjects in Tai Po District who had suffered from acute illness in the past month, to examine the profile of TCM users in the District. Women, older residents, unemployed workers, low skill laborers, current smokers and subjects dissatisfied with the quality of private sector clinics were significantly more likely to consult TCM practitioners. 相似文献
893.
Two cases of Kikuchi disease showed variable nodal enhancing features, including homogeneous enhancement and focal or extensive nodal necrosis on contrast-enhanced CT scans. At MR imaging, the area of central necrosis was isointense or hypointense on T1-weighted images and had a lower signal than nonnecrotic areas on T2-weighted images. The CT appearance of Kikuchi disease can be variable and can mimic not only lymphoma but various nodal diseases with nodal necrosis, including metastasis and tuberculosis. 相似文献
894.
OBJECTIVE: To provide long-term follow-up information on a large series of patients with choroidal osteoma. METHODS: Review of patients with a diagnosis of choroidal osteoma who had been examined at the Bascom Palmer Eye Institute, Miami, Fla, or known to one of us (J.D.M.G.). Information was obtained from hospital medical records or by a questionnaire sent to referring ophthalmologists. Life-table analysis was used to study the loss of vision and development of choroidal neovascularization. RESULTS: We followed up 36 patients, 31 (89%) were female, mean age, 21 years (range, 5-54 years) for a mean of 10 years (range, 2-22 years). Growth was observed for 9 (41%) of 22 well-documented osteomas. The probability of loss of visual acuity to 20/200 or worse was 58% by 10 years and 62% by 20 years. The probability of developing choroidal neovascularization was 47% by 10 years and 56% by 20 years. Successful treatment of the choroidal neovascularization with laser photocoagulation was performed for 5 (25%) of 20 patients. CONCLUSIONS: Most patients with choroidal osteomas maintain good vision in at least 1 eye, but they have a high risk of developing choroidal neovascularization. When this occurs, only a minority can be successfully treated with laser photocoagulation. 相似文献
895.
J Reith HS J?rgensen H Nakayama HO Raaschou TS Olsen 《Canadian Metallurgical Quarterly》1998,160(50):7266-7269
The aim of the study was to determine the relationships between seizures during the early phase of stroke (early seizures, ES) and stroke outcome, and to identify predictors of ES. The study was prospective, consecutive and community-based, and included 1197 patients with acute stroke. We determined the number and type of seizures, initial stroke severity, infarct size, mortality, and outcome in survivors. Stroke severity was measured on admission, weekly, and at discharge using the Scandinavian Stroke Scale (SSS). Multiple logistic and linear regression outcome analyses included relevant confounders and potential predictors. Fifty patients (4.2%) had seizures within 14 days of the stroke. In the multivariate analyses, only initial stroke severity was related to ES. For each 10-point increase in stroke severity (SSS score), the relative risk of ES increased by a factor of 1.65 (95% confidence interval, 1.4 to 1.9) (p < 0.0001). ES did not influence the risk of death during hospital stay (p = 0.56). In survivors, ES was related to a better outcome, equivalent to an improvement in SSS score of 5.7 points (SE [b] = 1.8; p = 0.002). The decisive factor of ES was initial stroke severity. ES per se was not related to mortality. Surprisingly, in survivors, ES predicted a better outcome. We explain this finding by a relatively larger ischaemic penumbra in patients who have ES after a stroke. 相似文献
896.
JH Vos TS van den Ingh FC Ramaekers RF Molenbeek M de Neijs FN van Mil D Ivanyi 《Canadian Metallurgical Quarterly》1993,30(4):352-361
Eight canine tumors originating from specific glandular structures in the anal region, as well as metastatic tumor tissue of two of these cases (case Nos. 7, 8), were immunohistochemically analyzed using various monoclonal antibodies (MoAbs) directed against human keratin types, vimentin, neurofilament proteins, and alpha-smooth muscle actin. These tumors also were stained for the broad-spectrum neuroendocrine markers neuron-specific enolase (NSE) and synaptophysin. In histologically normal canine anal structures, alpha-smooth muscle actin and NSE antibodies stained basally localized (probably myoepithelial) cells in the anal glands and the anal sac glands. NSE staining also was present in a limited number of luminal cells in both anal glands and anal sac glands. Synaptophysin labeling was not observed in any of these glandular structures. Histologically, the tumors were differentiated into well- and moderately differentiated perianal gland tumors (n = 5) and carcinomas without perianal gland differentiation (n = 3), corresponding to the so-called apocrine carcinomas of the anal region. Immunohistochemically, the perianal gland tumors could be differentiated from the carcinomas by marked differences in staining pattern with the various keratin MoAbs, particularly MoAbs directed against human keratin types 7 and 18. The keratin-staining characteristics of the carcinomas suggest a glandular luminal cell origin. Metastases of the carcinomas showed loss of some keratin-staining characteristics as compared with the primary tumor. Staining for NSE was only observed in solitary cells and small cell clusters in the carcinomas and their metastases, whereas the alpha-smooth muscle actin antibody did not react with the carcinoma cells. None of the tumors stained for neurofilament proteins or synaptophysin. An unequivocal neuroendocrine nature of the carcinomas could not be substantiated by our immunohistochemical study, although the presence of a population of neuroendocrine cells within these neoplasms seems likely. Because the immunohistochemical features of the carcinomas with respect to various keratin MoAbs and NSE are similar to those of the anal glands and the anal sac glands, both these glands might be considered as site of origin of these carcinomas. 相似文献
897.
898.
T Hendler R Gross E Goshen M Faibel S Hirshmann TS Zwass L Grunhaus J Zohar 《Canadian Metallurgical Quarterly》1997,133(9):337-42, 416
The common structural and functional brain imaging techniques are described from a practical, clinical point of view. The clinical indications for brain imaging in psychiatry are reviewed in relation to the specific limitations and advantages of each technique. The clinical applications of computerized tomography (CT), magnetic resonance imaging (MRI) and single photon emission computerized tomography (SPECT) are discussed in relation to the differential diagnosis between organic and functional psychiatric disorders. In a 55-year-old man with late onset of behavioral changes but without neurological signs the application of structural brain imaging (CT and MRI) in case management was demonstrated. The imaging findings involved the differential diagnosis between depression and focal brain lesions. In a 38-year-old man with personality changes and depression following a traumatic brain injury, time interval repeated functional brain imaging (SPECT) was used. Brain imaging reflected improvement in clinical status following treatment and was able to differentiate between reversible and permanent traumatic brain injuries. The superior yield of time interval repeated functional imaging in diagnosis and management of postconcussion syndrome is discussed. 相似文献
899.
BACKGROUND: Smooth muscle hamartoma is an uncommon lesion. Diagnosis is usually made at birth in infants presenting a plaque with minimal or no infiltration and covered with long dark hairs. Congenital forms with multiple plaques are rarely reported. CASE REPORT: A 5-day-old infant (normal pregnancy and delivery) had plaques localized on the buttocks, the left thigh, leg and shoulder and the right ankle. The plaques were minimally infiltrative and covered with long black hairs. Histology examination showed hyperplastic smooth muscle bundles with varying orientation. The diagnosis was smooth muscle hamartoma. The rest of the clinical examination was normal. CONCLUSION: This case of congenital smooth muscle hamartoma showed a particular form with partially regressive multiple plaques. 相似文献
900.