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991.
992.
OBJECTIVE: Usually it is not possible to study the initial systemic response in patients with acute pancreatitis in the first hours after onset of the disease. We used postendoscopic retrograde pancreatography (ERP) pancreatitis as a model to study cytokine and anticytokine release in the early phase of human acute pancreatitis. METHODS: Post-ERP pancreatitis was defined as a threefold increase in serum amylase and at least two of the following clinical symptoms: abdominal pain, nausea, vomiting or peritonism 24 h after ERP. Serum levels of pro-inflammatory cytokines interleukin-1beta (IL-1beta), interleukin-6 (IL-6), interleukin-8 (IL-8), tumour necrosis factor alpha (TNF), as well as endogenous antagonistic mediators of the systemic inflammatory response such as soluble tumour necrosis factor alpha receptors p55 (TNFR p55) and p75 (TNFR p75), and IL-1-receptor antagonist (IL-1-RA) and interleukin-2-receptor (IL-2R) as indicators of lymphocyte activation were measured before and 0, 1, 4, 12, 24 and 48 h after ERP. In nine patients with acute post-ERP pancreatitis, these parameters were monitored daily until C-reactive protein (CRP) was within normal ranges and were compared to patients without pancreatitis after ERP. RESULTS: IL-1beta was not detectable in five patients with and four patients without post-ERP pancreatitis. The values of the remaining patients in both groups were lower than 3.9 pg/ml. IL-8 and IL-1-RA serum concentrations peaked 12 h after ERP (132.9 and 3245.0 pg/ml respectively) compared to patients without post-ERP pancreatitis (25.8 and 389.9 pg/ml respectively). The IL-6 concentration increased to 81.6 pg/ml (8.0 pg/ml in control patients) 24 h after ERP, while the peak values for CRP were measured 72 h after ERP (164.0 versus 7.7 mg/l). IL-2R content was maximally elevated 144 h after ERP (688.8 versus 255.9 U/ml), while concentrations of TNF and its receptors showed no significant change over time. CONCLUSION: The initial response of the cytokine network to damage of the human pancreas leading to acute pancreatitis includes the release of IL-8 and the IL-1 antagonist IL-1-RA, while IL-1beta is not found in the systemic circulation. The TNF system does not seem to be involved as indicated by the lack of detectable changes in TNF and the soluble TNFR p55 and p75 serum concentrations. Lymphocyte activation as indicated by elevated IL-2R levels occurred days after the initial trauma. Even mild post-ERP pancreatitis leads to significant systemic release of cytokines and their biological counterparts. 相似文献
993.
F Tranquart S Arsene AS Aubert-Urena I Desbois C Audrerie C Rossazza L Pourcelot 《Canadian Metallurgical Quarterly》1998,26(3):119-124
Critical issues in diagnosis and treatment of pituitary disease are surveyed. The most relevant clinical aspects of hyperprolactinemia, acromegaly, Cushing's disease, secondary hyperthyroidism, syndrome of inappropriate ADH secretion, panhypopituitarism, growth hormone deficiency, gonadotropin deficiency, ACTH deficiency, TSH deficiency, and diabetes insipidus are discussed. Diagnostic and therapeutic issues in the approach to pituitary adenomas, craniopharyngiomas and pituitary apoplexy are analyzed. 相似文献
994.
BW Walsh LH Kuller RA Wild S Paul M Farmer JB Lawrence AS Shah PW Anderson 《Canadian Metallurgical Quarterly》1998,279(18):1445-1451
CONTEXT: Raloxifene is a selective estrogen receptor modulator that has estrogen-agonistic effects on bone and estrogen-antagonistic effects on breast and uterus. OBJECTIVE: To identify the effects of raloxifene on markers of cardiovascular risk in postmenopausal women, and to compare them with those induced by hormone replacement therapy (HRT). DESIGN: Double-blind, randomized, parallel trial. SETTING: Eight sites in the United States. PARTICIPANTS: 390 healthy postmenopausal women recruited by advertisement. INTERVENTION: Participants were randomized to receive 1 of 4 treatments: raloxifene, 60 mg/d; raloxifene, 120 mg/d; HRT (conjugated equine estrogen, 0.625 mg/d, and medroxyprogesterone acetate, 2.5 mg/d); or placebo. MAIN OUTCOME MEASURES: Change and percent change from baseline of lipid levels and coagulation parameters after 3 months and 6 months of treatment. RESULTS: At the last visit completed, compared with placebo, both dosages of raloxifene significantly lowered low-density lipoprotein cholesterol (LDL-C) by 12% (P < .001), similar to the 14% reduction with HRT (P < .001). Both dosages of raloxifene significantly lowered lipoprotein(a) by 7% to 8% (P < .001), less than the 19% decrease with HRT (P<.001). Raloxifene increased high-density lipoprotein-2 cholesterol (HDL2-C) by 15% to 17% (P < .05), less than the 33% increase with HRT (P < .001). Raloxifene did not significantly change high-density lipoprotein cholesterol (HDL-C), triglycerides, or plasminogen activator inhibitor-1 (PAI-1); whereas HRT increased HDL-C by 11% and triglycerides by 20%, and decreased PAI-1 by 29% (for all, P < .001). Raloxifene significantly lowered fibrinogen by 12% to 14% (P < .001), unlike HRT, which had no effect. Neither treatment changed fibrinopeptide A or prothrombin fragment 1 and 2. CONCLUSIONS: Raloxifene favorably alters biochemical markers of cardiovascular risk by decreasing LDL-C, fibrinogen, and lipoprotein(a), and by increasing HDL2-C without raising triglycerides. In contrast to HRT, raloxifene had no effect on HDL-C and PAI-1, and a lesser effect on HDL2-C and lipoprotein(a). Further clinical trials are necessary to determine whether these favorable biochemical effects are associated with protection against cardiovascular disease. 相似文献
995.
Sarcoidosis is a common multisystem disorder characterized by noncaseating epithelial granulomata, with osseous involvement typically seen in 5% of patients. While the lace-like or cystic pattern frequently seen in radiographs of the phalanges is well appreciated, sclerotic lesions of the spine are uncommon. We review a case of sarcoidosis of the cervical spine with sclerotic changes that mimicked blastic metastatic disease. 相似文献
996.
997.
998.
A Claris-Appiani G Ardissino AS Tirelli V Daccò C Corbetta L Guidi E Moretto BM Assael F Sereni 《Canadian Metallurgical Quarterly》1998,18(5):359-366
A mechanism of mate selection in humans is proposed and elaborated. It is further proposed that this mechanism constitutes one of the important factors for stability and the necessary longevity of the procreational dyad and therefore the procreational success of humans as a species. The concepts and mechanisms of assortative mating (homogamy) and that of complementarity of temperaments of the mates (heterogamy) which guide such selections are described, the relationships between the two are explored, and finally their possible early developmental origins are proposed. Evidence from a small study of 20 married couples' responses in temperament tests is offered as well as some illustrative case histories all pointing to those mechanisms. The argument is based mainly on principles of evolutionary psychology. 相似文献
999.
AS el-Madhun RJ Cox A Seime O S?vik LR Haaheim 《Canadian Metallurgical Quarterly》1998,16(2-3):156-160
Diabetes patients suffer frequent complications and some excess mortality after influenza virus infection. Despite widespread agreement that diabetic patients should be routinely vaccinated against influenza, some reports claim that diabetics have a poor immune response to influenza vaccine. We have performed a pilot study to examine the humoral immune response of juvenile diabetics and matched healthy controls vaccinated with inactivated trivalent influenza vaccine. By enzyme-linked immunospot assay we found that both groups had comparable magnitude and kinetics of influenza-specific antibody secreting cell response. The influenza-specific antibody response in both serum and oral fluid were similar for both groups, and also showing a kinetic profile in accordance with our earlier data for healthy adults. Our study did not detect a difference in the humoral immune response between juvenile diabetics and healthy controls. 相似文献
1000.
AS Krasilnikov IG Panyutin GM Samadashwily R Cox YS Lazurkin SM Mirkin 《Canadian Metallurgical Quarterly》1997,25(7):1339-1346
Pyrimidine/purine/purine triplexes are known to inhibit DNA polymerization. Here we have studied the mechanisms of this inhibition by comparing the efficiency of Vent DNA polymerase on triplex- and duplex-containing templates at different temperatures, Mg2+concentrations and time intervals with the thermal stability of the corresponding structures. Our results show that triplexes can only be by-passed at temperatures where thermal denaturation initiates, while duplexes, in contrast, are overcome at temperatures where they are quite stable. These results show that DNA polymerase cannot untangle triplex regions within DNA templates and seems to entirely depend on their thermal fluctuations. The high stability of triplexes at physiological temperatures and ambient conditions make them a barrier to polymerization. 相似文献