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101.
PW Pisters JL Abbruzzese NA Janjan KR Cleary C Charnsangavej MS Goswitz TA Rich I Raijman RA Wolff R Lenzi JE Lee DB Evans 《Canadian Metallurgical Quarterly》1998,16(12):3843-3850
PURPOSE: To evaluate the toxicities, radiographic and pathologic responses, and event-free outcomes with combined modality treatment that involves preoperative rapid-fractionation chemoradiation, pancreaticoduodenectomy, and electron-beam intraoperative radiation therapy (EB-IORT) for patients with resectable pancreatic adenocarcinoma. PATIENTS AND METHODS: Patients with radiographically resectable localized adenocarcinoma of the pancreatic head were entered onto a preoperative protocol that consisted of a 2-week course of fluorouracil (5-FU) 300 mg/m2 daily 5 days per week and concomitant rapid-fractionation radiation 30 Gy, 3 Gy daily 5 days per week. Radiographic restaging was performed 4 weeks after chemoradiation, and patients with localized disease underwent pancreaticoduodenectomy with EB-IORT 10 to 15 Gy. RESULTS: Thirty-five patients were entered onto the study and completed chemoradiation, 34 (97%) as outpatients. Three patients (9%) experienced grade 3 nausea and vomiting; no other grade 3 or 4 toxicities were observed. Of the 27 patients taken to surgery, 20 patients (74%) underwent pancreaticoduodenectomy with EB-IORT. All patients had a less than grade III pathologic response to preoperative chemoradiation. At a median follow-up of 37 months, the 3-year survival rate in patients who underwent combined modality therapy was 23%. CONCLUSION: Combined modality treatment with preoperative rapid-fractionation chemoradiation, pancreaticoduodenectomy, and EB-IORT is associated with minimal toxicity and excellent locoregional control. This represents one approach to maximize the proportion of patients who receive all components of combined modality therapy and avoids the toxicity of pancreaticoduodenectomy in patients found to have metastatic disease at the time of restaging. 相似文献
102.
103.
JL Bowtell GP Leese K Smith PW Watt A Nevill O Rooyackers AJ Wagenmakers MJ Rennie 《Canadian Metallurgical Quarterly》1998,85(5):1744-1752
The aim of this study was to investigate dietary protein-induced changes in whole body leucine turnover and oxidation and in skeletal muscle branched chain 2-oxo acid dehydrogenase (BCOADH) activity, at rest and during exercise. Postabsorptive subjects received a primed constant infusion of L-[1-13C,15N]leucine for 6 h, after previous consumption of a high- (HP; 1.8 g . kg-1 . day-1, n = 8) or a low-protein diet (LP; 0.7 g . kg-1 . day-1, n = 8) for 7 days. The subjects were studied at rest for 2 h, during 2-h exercise at 60% maximum oxygen consumption, then again for 2 h at rest. Exercise induced a doubling of both leucine oxidation from 20 micromol . kg-1 . h-1 and BCOADH percent activation from 7% in all subjects. Leucine oxidation was greater before (+46%) and during (+40%, P < 0.05) the first hour of exercise in subjects consuming the HP rather than the LP diet, but there was no additional change in muscle BCOADH activity. The results suggest that leucine oxidation was increased by previous ingestion of an HP diet, attributable to an increase in leucine availability rather than to a stimulation of the skeletal muscle BCOADH activity. 相似文献
104.
RE Howells CW Redman KK Dhar P Sarhanis C Musgrove PW Jones J Alldersea AA Fryer PR Hoban RC Strange 《Canadian Metallurgical Quarterly》1998,4(10):2439-2445
Epithelial ovarian cancer is generally associated with a poor outcome, although the mechanisms that determine survival and progression-free interval (PFI) are unclear. Data from ovarian tumors showing associations between (a) null genotypes at the glutathione S-transferase GSTM1 and GSTT1 loci and expression of p53 protein and (b) outcome and expression of p53 suggest that polymorphism at these loci is a factor determining outcome. Accordingly, we have studied the association between the GSTM1 null and GSTT1 null genotypes and survival and PFI in 148 women with epithelial ovarian cancer. Although we did not find an association between individual genotypes and outcome, women with both GSTM1 null and GSTT1 null genotypes demonstrated poorer survival (P = 0.001) and reduced PFI (P = 0.003). Thus, no cases with both these genotypes survived past 42 months postdiagnosis. In contrast, 43% of the women without this combination survived beyond this time. Because response to chemotherapy is a major factor determining outcome in ovarian cancer, we also examined the data for associations between the glutathione S-transferase genotypes and response to such treatment. Thus, in 78 patients treated with chemotherapy, the combination of GSTM1 null and GSTT1 null was associated with unresponsiveness to primary chemotherapy (P = 0.004); none of the eight patients with both these genotypes responded, compared with 38 of 70 (54%) of patients with other genotype combinations. The effect of the combination of genotypes on survival and PFI was lost in a multivariate model that included response to chemotherapy as a confounding factor. This suggests that the combination of GSTM1 null/GSTT1 null is associated with outcome because of its influence on response to chemotherapy. These preliminary findings may provide a basis for the selection of patients for treatment with chemotherapeutic agents. 相似文献
105.
WA Ferens WC Davis MJ Hamilton YH Park CF Deobald L Fox G Bohach 《Canadian Metallurgical Quarterly》1998,66(2):573-580
Staphylococcus aureus is a major mastitis-causing pathogen in cattle. The chronic nature of bovine staphylococcal mastitis suggests that some products or components of S. aureus may interfere with the development of protective immunity. One class of molecules that could be involved are superantigens (SAgs). Although a significant number of mastitis isolates produce SAgs, the effect of these molecules on the bovine immune system is unresolved. To determine if immunosuppression caused by SAgs could play a role in pathogenesis, we monitored bovine lymphocytes exposed to staphylococcal enterotoxin C1 (SEC1). Activation of bovine lymphocytes by either SEC1 or concanavalin A (ConA) was influenced by the gammadelta/alphabeta T-cell ratio in the culture. Compared to ConA-induced stimulation, cultures stimulated with SEC1 generated small numbers of CD4+ alphabeta T cells expressing high levels of interleukin-2 receptor alpha chain (IL-2R alpha) and major histocompatibility complex class II (MHCII), suggesting that SAg exposure does not lead to full activation of these cells. This state of partial activation was most pronounced in cultures with a high gammadelta/alphabeta ratio. In contrast, significant numbers of CD8+ alphabeta T cells expressed high levels of IL-2R alpha and MHCII, regardless of the gammadelta/alphabeta ratio and the stimulant used. CD8+ blasts in cultures stimulated with SEC1 also expressed another activation marker, ACT3, previously detected predominantly on thymocytes and CD4+ T cells. Although gammadelta CD2- and CD2+ T cells expressed MHCII and IL-2R alpha following stimulation with SEC1, only a few cells increased to blast size, suggesting that they were only partially activated. The results suggest ways in which SAgs might facilitate immunosuppression that promotes the persistence of bacteria in cattle and contributes to chronic intramammary infection. 相似文献
106.
M. Andrew R. J. Hamilton J. B. Rossell 《European Journal of Lipid Science and Technology》1987,89(1):7-15
The hydrocarbons were extracted and isolated from the surface of both Sinapis arvensis and Brassica napus seeds. The major hydrocarbon of the weed seed was found to be hentriacontane (C31H64) whereas nonacosane (C29H60) was the predominant hydrocarbon in rapeseed. This can be used as a criterion upon which differentiation can be made. Total “wax” extracts of the two seed types were analysed by gas chromatography. The waxy material extracted from the weed seed was found to have a major peak at 3320 Kovats retention indices which was absent in all rapeseed varieties. By studying a series of known composites of rapeseed and wild mustard, the level of wild mustard contamination could be accurately determined down to a level of 1 % using a ratio of two peaks at 2900 and 3320 Kovats retention indices. 相似文献
107.
WC Duckworth CD Saudek A Giobbie-Hurder WG Henderson RR Henry DE Kelley SV Edelman FJ Zieve RA Adler JW Anderson RJ Anderson BP Hamilton TW Donner MS Kirkman NA Morgan 《Canadian Metallurgical Quarterly》1998,21(10):1596-1602
OBJECTIVE: To determine whether implantable insulin pump (IIP) and multiple-dose insulin (MDI) therapy have different effects on cardiovascular risk factors in insulin-requiring patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: A randomized clinical trial was conducted at seven Veterans Affairs medical centers in 121 male patients with type 2 diabetes between the ages of 40 and 69 years receiving at least one injection of insulin per day and with HbA1c, levels of > or =8% at baseline. Weights, blood pressures, insulin use, and glucose monitoring data were obtained at each visit. Lipid levels were obtained at 0, 4, 8, and 12 months, and free and total insulin levels were obtained at 0, 6, and 12 months. All medications being taken were recorded at each visit. RESULTS: No difference in absolute blood pressure, neither systolic nor diastolic, was seen between patients receiving MDI or IIP therapy, but significantly more MDI patients required anti-hypertensive medications. When blood pressure was modeled against weight and time, IIP therapy was significantly better than MDI therapy for systolic blood pressure in patients with BMI <33 and for diastolic blood pressure in patients with BMI >34 kg/m2. Total cholesterol levels decreased in the overall sample, but IIP patients exhibited significantly higher levels than MDI patients. Triglyceride levels increased over time for both groups, with IIP patients having significantly higher levels than patients in the MDI group. BMI was a significant predictor of, and inversely proportional to, HDL cholesterol level. No difference in lipid-lowering drug therapy was seen between the two groups. Free insulin and insulin antibodies tended to decrease in the IIP group as compared with the MDI group. C-peptide levels decreased in both groups. CONCLUSIONS: IIP therapy in insulin-requiring patients with type 2 diabetes has advantages over MDI therapy in decreasing the requirement for antihypertensive therapy and for decreasing total and free insulin and insulin antibodies. Both therapies reduce total cholesterol and C-peptide levels. 相似文献
108.
The activity of alkaline phosphatase (AP) was studied in adults of highly active (HA) and low active (LA) Drosophila melanogaster strains and their F1 hybrids, both under normal conditions and after a heat shock (38 degrees C). Under normal conditions, the HA strain expressed a higher AP activity compared to that in the wild-type strain Canton-S and dominated in respect to this character. The AP activity showed a sexual dimorphism, as it was higher in females of both strains. Heat shock (38 degrees C) induced no alterations in the AP activity of D. melanogaster. 相似文献
109.
BR Babu SJ Zhu AV Ramayya JH Hamilton LK Peker MG Wang TN Ginter J Kormicki WC Ma JD Cole R Aryaeinejad K Butler-Moore YX Dardenne MW Drigert GM Ter-Akopian YT Oganessian JO Rasmussen S Asztalos IY Lee AO Macchiavelli SY Chu KE Gregorich MF Mohar S Prussin MA Stoyer RW Lougheed KJ Moody JF Wild 《Canadian Metallurgical Quarterly》1996,54(2):568-571
110.
Recombinant papillomavirus-like particles have recently been shown to be highly effective for the prevention of papillomavirus infections and associated tumors, and a virus-like particle-based vaccine against the most prevalent HPV causing genital infection in humans will be developed in the near future. Another use of these virus-like particles may lie in gene therapy and DNA immunization. We report here that human papillomavirus-like particles composed of the major capsid protein (L1) of HPV-16 are able to package unrelated plasmid DNA in vitro and then to deliver this foreign DNA to eukaryotic cells with the subsequent expression of the encoded gene. The results indicate higher gene transfer than with DNA alone or with liposome. Virus-like particles are a very promising vehicle for delivering genetic material into target cells. Moreover, the preparation of the gene transfer vehicle is relatively easy. 相似文献