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101.
This longitudinal study of adolescents from a Nova Scotia coastal town examined whether change in self-reported depressive symptoms could be predicted from adolescents' concurrent and prior reports of anxiety symptoms and risk behaviors. Questionnaires were completed by 131 youths (80 females, 51 males; aged 12–17 yrs) in their classrooms 2 years apart. Results show that adolescents' concurrent reports of involvement in risk behaviors were linked to an increase in depressive symptoms only when they also were high on anxiety symptoms. Prior involvement in risk behaviors, but not prior anxiety symptoms, also predicted an increase in depressive symptoms. The importance of evaluating covariation among multiple types of symptoms and targeting the positive and negative consequences of risk behaviors adolescents is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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BW Ziegelaar JH Fitton AB Clayton ST Platten J Steer TV Chirila 《Canadian Metallurgical Quarterly》1998,9(8):849-862
We examined the regulation of collagenase production by the monocyte/macrophage THP-1 cell line when these cells were exposed to poly(2-hydroxyethyl methacrylate) (PHEMA) hydrogel surfaces with different chemistries and morphologies. Tissue culture modified polystyrene (TCP), used as a control surface, induced the maximum collagenase response. Copolymer hydrogels containing 2-ethoxyethyl methacrylate (EMA) or methyl methacrylate (MMA) also induced a high response, while PHEMA hydrogels induced a low level response and the phosphorylated hydrogel induced no response. This pattern was altered when the morphology of the hydrogels was changed to that of a sponge. The overall enzyme response to the sponge hydrogels was lower than that to the homogeneous hydrogels. Sponges containing EMA and MMA produced low level response relative to the TCP control. PHEMA and phosphorylated sponges produced little and no response respectively. The dramatically reduced enzyme response to phosphorylated surfaces was not a consequence of cell death, and may be a phenomenon related to changes in cell surface charge. 相似文献
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RK Valicenti LG Gomella M Ismail SG Mullholland RO Petersen BW Corn 《Canadian Metallurgical Quarterly》1998,82(10):1909-1914
BACKGROUND: The authors evaluated the effect of postoperative radiation therapy on freedom from biochemical failure (bNED) in men with prostate carcinoma who had pathologic seminal vesicle invasion after radical prostatectomy and negative pelvic lymph node dissection (pT3cN0). METHODS: Between 1989 and 1995, 375 men underwent radical prostatectomy at Thomas Jefferson University Hospital. Fifty-three men (13%) had pT3cN0 prostate carcinoma and were the subject of this analysis. Men in whom prostate specific antigen (PSA) could not be detected were deemed free of biochemical failure. RESULTS: Of the 53 men with pT3cN0 prostate carcinoma, 18 had an elevated PSA immediately after surgery and received salvage radiation therapy (RT). The 3-year bNED rate for this group was only 38%. At 3 months, PSA could not be detected in the other 35 men. Fifteen of those 35 men underwent early adjuvant RT, and the other 20 were observed for biochemical failure. The 3-year bNED rate for the 15 patients treated with immediate adjuvant RT was 86%, compared with 48% for the 20 men who were observed (P = 0.01). CONCLUSIONS: These data suggest that early adjuvant RT for men with pT3cN0 prostate carcinoma and no detectable PSA postoperatively reduces the likelihood of future biochemical failure. Men with pT3cN0 prostate carcinoma and a persistently elevated postoperative PSA level are less likely to benefit from RT and should be considered for systemic therapy. 相似文献
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TA Millward CW Heizmann BW Sch?fer BA Hemmings 《Canadian Metallurgical Quarterly》1998,17(20):5913-5922
Ndr is a nuclear serine/threonine protein kinase that belongs to a subfamily of kinases identified as being critical for the regulation of cell division and cell morphology. The regulatory mechanisms that control Ndr activity have not been characterized previously. In this paper, we present evidence that Ndr is regulated by EF-hand calcium-binding proteins of the S100 family, in response to changes in the intracellular calcium concentration. In vitro, S100B binds directly to and activates Ndr in a Ca2+-dependent manner. Moreover, Ndr is recovered from cell lysates in anti-S100B immunoprecipitates. The region of Ndr responsible for interaction with Ca2+/S100B is a basic/hydrophobic motif within the N-terminal regulatory domain of Ndr, and activation of Ndr by Ca2+/S100B is inhibited by a synthetic peptide derived from this region. In cultured cells, Ndr is rapidly activated following treatment with Ca2+ ionophore, and this activation is dependent upon the identified Ca2+/S100B-binding domain. Finally, Ndr activity is inhibited by W-7 in melanoma cells overexpressing S100B, but is unaffected by W-7 in melanoma cells that lack S100B. These results suggest that Ndr is regulated at least in part by changes in the intracellular calcium concentration, through binding of S100 proteins to its N-terminal regulatory domain. 相似文献
106.
Diabetic ulcers are the most common foot injuries leading to lower extremity amputation. Family physicians have a pivotal role in the prevention or early diagnosis of diabetic foot complications. Management of the diabetic foot requires a thorough knowledge of the major risk factors for amputation, frequent routine evaluation and meticulous preventive maintenance. The most common risk factors for ulcer formation include diabetic neuropathy, structural foot deformity and peripheral arterial occlusive disease. A careful physical examination, buttressed by monofilament testing for neuropathy and noninvasive testing for arterial insufficiency, can identify patients at risk for foot ulcers and appropriately classify patients who already have ulcers or other diabetic foot complications. Patient education regarding foot hygiene, nail care and proper footwear is crucial to reducing the risk of an injury that can lead to ulcer formation. Adherence to a systematic regimen of diagnosis and classification can improve communication between family physicians and diabetes subspecialists and facilitate appropriate treatment of complications. This team approach may ultimately lead to a reduction in lower extremity amputations related to diabetes. 相似文献
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Heavily cold-rolled sheet material of 99.9 pct purity Ag has been recrystallized at varying temperatures to give average grain diameters,l, in the range between 1 and 60 μ. For this material, the yield stress, flow stress at several strain values, and fracture stress follow the Hall-Petch relation: $$\sigma _\varepsilon = \sigma o_\varepsilon + k_\varepsilon l^{ - 1/2} $$ whereσ ε is the flow stress at a particular value of strain, ε, ands o ε andk ε are the experimental constants appropriate to a particular strain value. The range in grain size obtained for this material was sufficiently large to determine that silver can be appreciably strengthened by grain size refinement and that several other relations previously suggested to relate the stress and grain size could be discounted. The finest grain sizes were measured from replicas of etched specimens as viewed with the electron microscope. It is proposed that this type of grain size strengthening may be responsible for the exceptional strength which occurs in certain films of silver fabricated by vapor deposition techniques. 相似文献
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