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Compliance of the lungs and thorax was studied in 65 pregnant women during cesarean section. The measurements were carried out in a group of healthy controls and in patients with preeclampsia. The detected changes indicated increased rigidity of the lungs even in normal pregnancy. Comparison of the results indicates an appreciable increase of rigidity of the lungs in patients with preeclampsia, this permitting us to regard it as a status involving interstitial pulmonary hyperhydration. 相似文献
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JL Grem N McAtee RF Murphy FM Balis E Cullen AP Chen JM Hamilton SM Steinberg M Quinn JM Sorensen SG Arbuck D Lawrence J Pang CJ Allegra 《Canadian Metallurgical Quarterly》1997,3(7):1125-1134
The combination of IFN-alpha-2a (IFN-alpha) and IFN-gamma-1b (IFN-gamma) has been found to produce more than additive cytotoxicity with fluorouracil (5-FU) in HT 29 colon cancer cells due to enhanced DNA-directed effects. We therefore studied the combination of IFN-gamma with IFN-alpha, 5-FU, and leucovorin (LV) in a clinical trial. Fifty-three patients received an initial cycle of 5 million units (MU)/m2 IFN-alpha s.c. on days 1-7 with 500 mg/m2 LV and 370 mg/m2 5-FU i.v. on days 2-6. IFN-gamma was then added once tolerable doses of 5-FU and IFN-alpha were established for each patient. IFN-gamma was administered at one of six dose levels between 0.3-4.8 MU/m2 s.c. on days 1-7. This design permitted comparison of the clinical toxicity and pharmacokinetics of 5-FU in two consecutive cycles in an individual treated with the same doses of 5-FU/LV/IFN-alpha in the absence and presence of IFN-gamma. In 43 matched patient cycles, the addition of IFN-gamma did not seem to worsen gastrointestinal toxicity, and skin toxicity tended to be milder. 5-FU clearance was higher in 14 cycles with IFN-gamma compared to the patient's prior cycle with the same doses of 5-FU/LV/IFN-alpha: 798 +/- 309 versus 601 +/- 250 ml/min/m2 (mean +/- SD; P = 0.04). In these 28 cycles, the median 5-FU clearance was significantly lower in 11 cycles that were complicated by more severe diarrhea: 524 versus 798 ml/min/m2 (grade 2 versus 0-1; P = 0. 0032). Overall, 38% and 26% of patients had grade 3-4 diarrhea and mucositis. Dose reductions of IFN-gamma for chronic fatigue, malaise, or anorexia were ultimately required more frequently with >/=2.4 MU/m2 (P = 0.018), and the maximum tolerated dose of IFN-gamma was considered to be 1.2 MU/m2/ day. Objective responses were seen in 41% of 29 measurable colorectal cancer patients. Compared to our previous experience with 5-FU/LV/IFN-alpha, IFN-gamma and IFN-alpha appeared to have opposite effects on 5-FU clearance. These results suggest that any potential benefit of adding IFN-alpha to 5-FU/LV on this schedule may not depend solely on alterations in 5-FU clearance. 相似文献
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TJ Gan PS Glass ST Howell AT Canada AP Grant B Ginsberg 《Canadian Metallurgical Quarterly》1997,87(4):779-784
BACKGROUND: Subhypnotic doses of propofol possess direct antiemetic properties. The authors sought to determine the plasma concentration of propofol needed to effectively manage postoperative nausea and vomiting. METHODS: Patients aged 18-70 yr who were classified as American Society of Anesthesiologists physical status 1 or 2 and had surgery during general anesthesia were approached for the study. Only patients who had nausea (verbal rating score > 5 on a 0- to 10-point scale), retching, or vomiting in the postanesthetic care unit participated. Propofol was administered to these patients to achieve target plasma concentrations of 100, 200, 400, and 800 ng/ml using a computer-assisted continuous infusion device. Target concentrations were increased every 15 min until patients described at least a 50% reduction in symptoms on the verbal rating score. An arterial blood sample was obtained at each step. The measured plasma propofol concentrations were used to analyze data. Blood pressure, heart and respiratory rates, arterial blood saturation, sedation score, and overall satisfaction with treatment were recorded. RESULTS: Of the 89 patients who consented to the study, 15 patients met entry criteria and were enrolled. Five of these patients also had retching or vomiting when they entered the study. Fourteen patients responded successfully to treatment. One patient did not achieve the required response at plasma concentrations of 830 ng/ml. Hence the success rate for the treatment of postoperative nausea and vomiting was 93%. Among patients who responded, the median plasma concentration associated with an antiemetic response was 343 ng/ml. There was no difference in sedation scores from baseline and no episodes of desaturation. Hemodynamic parameters were stable during the study. CONCLUSIONS: Propofol is generally efficacious in treating postoperative nausea and vomiting at plasma concentrations that do not produce increased sedation. Simulations indicate that to achieve antiemetic plasma propofol concentrations of 343 ng/ml, a bolus dose of 10 mg followed by an infusion of approximately 10 microg x kg(-1) x min(-1) are necessary. 相似文献
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PN Tariot L Schneider AP Porsteinsson 《Canadian Metallurgical Quarterly》1997,101(6):73-6, 81, 84 passim
Treatment of Alzheimer's disease has in the past been limited to empirical trials of psychotropics for relief of behavioral complications. At present, tacrine and doneprezil are the only FDA-approved antidementia agents available. In the very near future, however, other cholinesterases inhibitors (e.g., ENA 713, metrifonate, long-acting physostigmine) are expected to be approved for clinical use. The evidence at this point suggests that they have modest but meaningful clinical effects and possible long-term benefits. Clinical use of the newer agents is likely to be influenced by their side-effect profiles, which consist largely of cholinergic effects, although without the hepatotoxic effects associated with tacrine. To what extent these agents are accepted by patients and physicians remains to be seen. On the one hand, benefits are modest; on the other, these medications are increasingly safe. Continuing research is clarifying the role of cholinergic therapy in relieving behavioral symptoms, as well as the possible side effects on rates of illness progression, institutionalizaton, and even mortality. In the not-too-distant future, physicians can expect to see a variety of medications, now in early stages of development, that are intended to affect cholinergic systems in other ways. Further down the road, a host of mechanism-based therapeutic strategies, which hope to deal with the first cause of this devastating illness, will have been assessed in clinical trials. 相似文献
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