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排序方式: 共有4516条查询结果,搜索用时 15 毫秒
991.
992.
BM Stiles DB Drake AJ Gear FH Watkins RF Edlich 《Canadian Metallurgical Quarterly》1997,15(5):669-671
In complex dislocations of the metacarpophalangeal joint, the volar plate is separated from the proximal phalanx and the metacarpal head is entrapped within surrounding tissue structures. These complex dislocations must be managed by open surgical reduction to reduce the dislocation and realign the volar plate. A 58-year-old male presented to the emergency department with a complex dislocation of the metacarpophalangeal joint of the left little finger, which was successfully treated by open reduction in the operating room. The indications for open reduction of metacarpophalangeal joint dislocations are reviewed. 相似文献
993.
994.
DL Flynn DP Becker VM Dilworth MK Highkin PJ Hippenmeyer KA Houseman LM Levine M Li AE Moormann A Rankin MV Toth CI Villamil AJ Wittwer BC Holwerda 《Canadian Metallurgical Quarterly》1997,15(1):3-15
This paper is a review of the literature on the possible association between osteoporosis and oral bone loss, with an emphasis on radiological studies. Such an association was first suggested in 1960. Subsequent histomorphometric and microradiographic studies showed that after the age of 50 there was a marked increase in the cortical porosity of the mandible, with this increase being greater in the alveolar bone than the mandibular body; and that with this increase in porosity, there was a concomitant decrease in bone mass, which appeared to be more pronounced in females than in males, with the loss in bone mineral content estimated to be 1.5% per year in females and 0.9% in males. These studies also demonstrated a considerable amount of variation in the amounts of cortical and trabecular bone within and among individuals. Subsequent clinical studies reported associations between the bone densities of jaws and (1) metacarpals, (2) forearm bones, (3) vertebrae and (4) femurs. These studies indicated that women had lower mandibular bone mineral content (BMC) than men and that age-related loss of bone was more pronounced in women after the age of 50 years than in men of the same age, as was the case for the rest of the body. It was suggested that systemic factors responsible for osteoporotic bone loss may combine with local factors (periodontal diseases) to increase rates of periodontal alveolar bone loss. Although not all studies found associations between osteoporosis and oral bone loss, the conclusion of this review is that such an association exists; yet additional longitudinal investigations are needed to confirm this, and before the implications of this association could be fully utilized in clinical dentistry, inexpensive methods must be developed for sensitive and specific measures of oral bone loss. 相似文献
995.
AJ Lodge A Undar CW Daggett TM Runge JH Calhoon RM Ungerleider 《Canadian Metallurgical Quarterly》1997,63(5):1243-1250
BACKGROUND: Pulsatile perfusion systems have been proposed as a means of improving end-organ perfusion during and after cardiopulmonary bypass. Few attempts have been made to study this issue in an infant model. METHODS: Neonatal piglets were subjected to nonpulsatile (n = 6) or pulsatile (n = 7) cardiopulmonary bypass and 60 minutes of circulatory arrest. Cerebral, renal, and myocardial blood flow measurements were obtained at baseline, on bypass before and after circulatory arrest, and after bypass. RESULTS: Cerebral blood flow did not differ between groups at any time and was diminished equally in both groups after circulatory arrest. Renal blood flow was diminished in both groups during bypass but was significantly better in the pulsatile group than in the nonpulsatile group prior to, but not after, circulatory arrest. Myocardial blood flow was maintained at or above baseline in the pulsatile group throughout the study, but in the nonpulsatile group, it was significantly lower than baseline during CPB prior to circulatory arrest and lower compared with baseline and with the pulsatile group 60 minutes after CPB. CONCLUSIONS: Pulsatile bypass does not improve recovery of cerebral blood flow after circulatory arrest, may improve renal perfusion during bypass but does not improve its recovery after ischemia, and may have beneficial effects on myocardial blood flow during bypass and after ischemia compared with nonpulsatile bypass in this infant model. 相似文献
996.
Strategies have been developed to characterize tumor antigens recognized by cytolytic T lymphocytes (CTL). We use a genetic approach based on the transfection of HLA genes and cDNA libraries in COS cells to isolate the gene producing the antigenic peptide. The tumor-specific expression of this gene can be evaluated by cDNA synthesis and quantitative PCR amplification. Transfection of fragments of the isolated gene allows the identification of the region encoding the antigenic peptide. Peptides are synthesized and tested for their ability to sensitize target cells to lysis by the CTL. 相似文献
997.
Earlier studies by other investigators have shown that S-adenosylmethionine (SAM) has the capacity to attenuate liver injury in experimental animals. In a recent study in this laboratory, it was shown that when supplemental dietary betaine was given to control and ethanol-fed rats at the level of 0.50% (W/V), SAM levels were doubled in the livers of control animals and increased fivefold in livers of ethanol-fed rats. The increased levels of SAM in the livers of ethanol-fed animals protected the livers from fatty infiltration due to ethanol feeding. In this study, an attempt was made to determine the minimum level of dietary betaine that protects against the fatty infiltration. Levels of betaine at 0.05%, 0.10%, 0.25%, and 0.50% in semiliquid control and alcohol diets were tested in rats for 30 days. When hepatic betaine, SAM, and triglyceride levels were determined, it was demonstrated that only the dietary level of betaine at 0.50% supplied enough hepatic betaine to generate the level of SAM that was required to protect against the alcoholic steatosis resulting from the dietary ethanol. These results suggest that betaine, when given in sufficient amounts, may be a promising therapeutic agent in the treatment of liver disease. 相似文献
998.
SS Phillips DB Baird VV Joshi AJ Rosenberg EO Janosko 《Canadian Metallurgical Quarterly》1997,17(3):497-502
We report a case of Crohn's disease with involvement of the foreskin in a 12-year-old boy. One year previously, on the basis of clinical features (diarrhea with blood, perianal fissures) and histologic examination, a diagnosis of Crohn's disease was made. Subsequently, he developed phimosis and balanitis and underwent circumcision. Sections submitted from the foreskin revealed noncaseating granulomatous inflammation consistent with Crohn's disease. Crohn's disease with involvement of the genitalia is unusual. Only 26 cases including our case have been reported in the scientific literature. We have analyzed these cases with emphasis on gender, age, clinical features, duration of Crohn's disease, and probable mode of spread to the genitalia. Careful examination of sections from genital lesions, including those submitted from the foreskin, is essential to detect small isolated granulomas that may then lead to the diagnosis of inflammatory bowel disease. 相似文献
999.
AJ de Beaufort JA Langermans AM Matze-van der Lans PS Hiemstra JM Vossen R van Furth 《Canadian Metallurgical Quarterly》1997,46(6):597-600
The binding and opsonic properties of C-reactive protein (CRP) for various species of bacteria were investigated. CRP bound more avidly to killed than to live Streptococcus pneumoniae, the binding varying among various serotypes; CRP hardly bound to a number of other bacterial species studied. CRP enhanced complement-dependent phagocytosis of live S. pneumoniae by granulocytes but did not enhance the phagocytosis of live Staphylococcus aureus or group B streptococci. We suppose that CRP may serve as an opsonin for killed bacteria and bacterial debris but is probably not an important opsonin for live bacteria other than S. pneumoniae. 相似文献
1000.