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51.
RN Shain JM Piper ER Newton ST Perdue R Ramos JD Champion FA Guerra 《Canadian Metallurgical Quarterly》1999,340(2):93-100
Using annual bite-wing radiographs, the incidence and progression of approximal caries (4d-7m) were assessed longitudinally in teenagers and adolescents whose treatment had been based on remineralizing rather than restorative strategies. A closed cohort of 536 children initially was followed from 11 to 22 years of age. The scoring system was: 0 = no visible radiolucency; 1-2 = radiolucency in the enamel up to the enamel-dentin border; 3 = radiolucency with a broken enamel-dentin border but with no obvious progression in the dentin; 4 = radiolucency with obvious spread in the outer half of the dentin, and 5 = radiolucency in the inner half of the dentin. Caries rates were estimated as the number of new lesions/100 tooth surface-years, and the Kaplan-Meier estimate was used to calculate the cumulative survival time of each approximal surface. Three events were used: the transitions from states 0 to 2, 2 to 4 and 3 to 4. The results showed a considerable variation between the surfaces in both caries rates and survival time. For all surfaces combined, the median caries rate from state 0 to 2 was 3.9 new lesions/100 tooth surface-years; from state 2 to 4, the rate was 5.4, and from state 3 to 4 it was 20.3. Of the sound surfaces (state 0), 75% survived 6.3 years without reaching state 2. Given state 2, 75% survived 4.8 years without reaching the outer half of the dentin (state 4), while given a lesion at the enamel-dentin border (state 3), 75% survived 1.3 years without doing the same. The median survival time of lesions from state 3 to 4 was 3.1 years. The group with DMFSappr>1 at the age of 11-12 years had a risk of new approximal enamel lesions (state 0-2) that was 2.5 times greater than that of the group with DMFSappr = 0-1. 相似文献
52.
In a household survey in Guinea-Bissau, 319 episodes of diarrhea in children were followed by interviews every second day with the aim of investigating perceived morbidity and subsequent actions taken. The majority of the mothers had good knowledge of oral rehydration salts (ORS). However, only 58% of the episodes were treated with ORS and the amount given was insufficient. Mothers with no knowledge of ORS did not use it during the observed attack of diarrhea regardless of contact with a health center, which suggests that maternal knowledge is an important determinant of whether health personnel provide ORS. Children with diarrhea considered to be caused by teething were less likely to receive ORS in the acute phase (risk ratio = 0.6, 95% confidence interval [CI] = 0.5-0.9). Univariate analyses showed that the use of ORS was related to number of reported symptoms, the mother being the care taker, consultations, previous use of ORS, good knowledge of ORS, and having ORS sachets at home. Multivariate Cox regression analyses showed that the presence of ORS sachets at home at the onset of diarrhea was the strongest predictor of use (hazard ratio = 3.3, 95% CI = 1.9-3.6). Improved health education should focus more on the quantity of ORS needed, early signs of dehydration, treatment of teething diarrhea, and breast feeding, and address mothers who have no prior knowledge of ORS. Management of diarrhea may be improved by a more liberal distribution of ORS sachets. 相似文献
53.
ER Righini R Alvisi S Bortolazzi E Marangoni G Gritti 《Canadian Metallurgical Quarterly》1998,64(9):399-407
In the cranio-facial region the giant-cell reparative granuloma (GCRG) is a typical lesion of the maxillary bones. Because giant-cell reparative granuloma is not strictly a granuloma, clinically and histologically, many authors prefer call it giant-cell lesion (GCL). A review of the literature have along with our experiences is reported. Authors present 17 patients with giant-cell lesion and their results, treated at the Maxillo-Facial Department of Parma. Clinical, radiographic and pathologic features were evaluated and differential diagnosis was considered, showing the real great difficulty in differential diagnosis also and especially for surgical treatment. 相似文献
54.
ER Floyd 《Canadian Metallurgical Quarterly》1986,34(10):3246-3249
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56.
The type and distribution of keratins (K) in malignant tumors of eyelids were examined immunohistochemically to understand the pathomechanism of intercellular interactions. All of the tumor cells in the basal cell carcinoma were positive for K14, which is specific for basal cells, whereas all of them were negative for K10, which is specific for suprabasal layers in stratified squamous epithelia. These findings suggest that basal cell carcinoma may consist of uniform, basal cell-like tumor cells. On the other hand, the squamous cell carcinoma and sebaceous carcinoma, which were positive for either K14 or K10 to varying extent, may consist of various tumor cells with different types and degrees of differentiation. In these tumors, K14 was frequently detected throughout the border cells of the tumor mass. Apoptotic bodies were detected at the region where this continuous distribution of K14 was interrupted. These findings may help to clarify the pathomechanism of the interactions between the tumor cells and stromal cells. 相似文献
57.
58.
ER Moxon 《Canadian Metallurgical Quarterly》1997,350(9086):1240-1244
Genetics, cell biology, and whole-genome sequencing of pathogens have changed dramatically the opportunities to investigate the epidemiology, pathogenesis, diagnosis, and control of microbial diseases. For example, recombinant DNA and PCR are powerful tools used to isolate genes whose role in pathogenicity can be investigated in biologically relevant virulence assays. Vaccines that target one or more of these genes can then be developed. Complete genome sequences of microbes provide an inventory of the genes encoding every virulence factor and potential immunogen. Candidate vaccines can be selected and developed using various approaches, including the recent innovation of immunisation with nucleic acids. Although many successful vaccines have been and will continue to be developed through empirical approaches, molecular microbiology provides a rational basis for discovery, development, and implementation of safer, more effective and, potentially cheaper vaccines. 相似文献
59.
KM Egan MJ Stampfer BA Rosner D Trichopoulos PA Newcomb A Trentham-Dietz MP Longnecker R Mittendorf ER Greenberg WC Willett 《Canadian Metallurgical Quarterly》1998,7(5):359-364
For the study of the relationship of the pelviureteric system of one kidney to that of the contralateral one, bilateral cutaneous ureterostomy was performed in 14 dogs. The renal pelvis (RP) and ureter (U) of one side were distended separately with a balloon filled with saline in increments of 1 and 0.25 ml, respectively, and the pressure response of the contralateral RP and U was recorded. The test was repeated after anesthetization of the RP and U. RP distension with 1 ml of saline effected a pressure rise (P < 0.05) in the ipsilateral RP but no pressure response in the ipsilateral U or the contralateral RP or U (P > 0.05). RP distension with 2, 3, and 4 ml of saline induced a significant pressure rise in the ipsi- and contralateral RP but not in the ureters. Ureteric distension produced a pressure elevation (P < 0.05) on the ipsilateral U but had no effect on the contralateral U (P > 0.05) or on either of the renal pelves (P > 0.05). Distension of the anesthetized RP or U effected no pressure response in any of the ipsi- or contralateral RPs or Us. In conclusion, distension of the RP with large volumes led to an increase in pressure in the contralateral RP but not in the U. A reflex relationship is postulated to exist between the two renal pelves and to be mediated through a reflex we call the reno-renal pelvic reflex. It seems that this reflex acts to allow either of the kidneys to share an extra load of the other one by increasing the contractile activity of the RP, thus assumedly assisting the regulation of urine flow. 相似文献
60.
LJ Shaw ED Peterson LK Shaw KL Kesler ER DeLong FE Harrell LH Muhlbaier DB Mark 《Canadian Metallurgical Quarterly》1998,98(16):1622-1630
BACKGROUND: Exercise testing is useful in the assessment of symptomatic patients for diagnosis of significant or extensive coronary disease and to predict their future risk of cardiac events. The Duke treadmill score (DTS) is a composite index that was designed to provide survival estimates based on results from the exercise test, including ST-segment depression, chest pain, and exercise duration. However, its usefulness for providing diagnostic estimates has yet to be determined. METHODS AND RESULTS: A logistic regression model was used to predict significant (>/=75% stenosis) and severe (3-vessel or left main) coronary artery disease, and a Cox regression analysis was used to predict cardiac survival. After adjustment for baseline clinical risk, the DTS was effectively diagnostic for significant (P<0.0001) and severe (P<0.0001) coronary artery disease. For low-risk patients (score >/=+5), 60% had no coronary stenosis >/=75% and 16% had single-vessel >/=75% stenosis. By comparison, 74% of high-risk patients (score <-11) had 3-vessel or left main coronary disease. Five-year mortality was 3%, 10%, and 35% for low-, moderate-, and high-risk DTS groups (P<0.0001). CONCLUSIONS: The composite DTS provides accurate diagnostic and prognostic information for the evaluation of symptomatic patients evaluated for clinically suspected ischemic heart disease. 相似文献