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921.
EG Waters 《Canadian Metallurgical Quarterly》1977,50(5):511-517
A series is presented of 830 patients in whom elective appendectomy was performed at the time of laparotomy for other intraabdominal disease. Special emphasis is given to 490 such procedures among 1042 patients with abdominal hysterectomy, an incidence of 47%. This increases to 57% by exclusion of patients with previous appendectomy. The contraindications to elective appendectomy are discussed, as well as its morbidity, mortality, and complications. The author concludes that an elective appendectomy should be performed with abdominal and pelvic surgery whenever the opportunity is presented, provided that the procedure is not prohibited by the contraindications discussed. 相似文献
922.
923.
MJ Montes CG Tortosa C Borja AC Abadía F González-Gómez C Ruiz EG Olivares 《Canadian Metallurgical Quarterly》1995,34(3):188-194
PROBLEM: Although several studies have demonstrated that decidual stromal cells (DSC) can secrete cytokines in culture, none of these studies documented the purity of the cultures. Since other cells of the decidua, such as macrophages and epithelial cells, also produce cytokines, it is important to ensure purity of the culture so that cytokine production can be ascribed with confidence to DSC. METHOD: DSC from early human pregnancies were highly purified and maintained in culture. Basal secretion by these cells of IL-6, together with other cytokines considered critical for pregnancy (IL-1 beta, TNF alpha and IFN gamma), was measured with immunological techniques. RESULTS: We found that DSC in culture produce insignificant quantities of IL-1 beta, TNF alpha and IFN gamma, but appreciable amounts of IL-6. The production of this later cytokine was, however, inhibited by the effect of progesterone. CONCLUSIONS: Basal production of IL-6 by DSC may be involved in physiological functions at the maternal-fetal interface. Nevertheless, the secretion of this cytokine is regulated by progesterone, probably to prevent excessive production of this cytokine from triggering an inflammatory response that might compromise pregnancy. 相似文献
924.
J Riedlberger C Amsler M Doser U Straumann P Tru?l D Bailey S Barlag U Gastaldi R Landua C Sabev KD Duch M Heel H Kalinowsky F Kayser E Klempt B May O Schreiber P Weidenauer M Ziegler W Dahme F Feld-Dahme U Schaefer WR Wodrich S Ahmad JC Bizot B Delcourt J Jeanjean H Nguyen N Prevot EG Auld DA Axen KL Erdman B Howard R Howard BL White M Comyn G Beer GM Marshall LP Robertson M Botlo C Laa H Vonach 《Canadian Metallurgical Quarterly》1989,40(6):2717-2731
925.
JA Bonner WL McGinnis PJ Stella RF Marschke JA Sloan EG Shaw JA Mailliard ET Creagan RK Ahuja PA Johnson 《Canadian Metallurgical Quarterly》1998,82(6):1037-1048
BACKGROUND: A three-arm Phase III randomized trial was performed to compare response rates, time to local or distant progression, and survival for patients with unresectable (Stage IIIA or IIIB) nonsmall cell lung carcinoma treated with standard fractionated thoracic radiotherapy (SFTRT) versus accelerated hyperfractionated thoracic radiotherapy (AHTRT) with or without combination etoposide and cisplatin chemotherapy. METHODS: This trial was initiated in 1992 by the North Central Cancer Treatment Group. Patients with Stage IIIA or IIIB nonsmall cell lung carcinoma were eligible. They were randomly assigned to either SFTRT (6000 centigray [cGy] in 30 fractions) or AHTRT (150 cGy twice daily to a total dose of 6000 cGy, with a 2-week break after the initial 3000 cGy); the AHTRT was given alone or with concomitant cisplatin (30 mg/m2, Days 1-3 and 28-30) and etoposide (100 mg/m2, Days 1-3 and 28-30). RESULTS: A total of 110 patients were entered on study. Eleven patients were declared ineligible or off study on the day of study entry. This analysis was confined to the 99 eligible patients. This article reports mature follow-up, because more than 80% of the patients have died. The median follow-up of living patients was 2.5 years. There were suggestions of improvement in the rates of freedom from local recurrence and survival for patients treated with AHTRT (with or without chemotherapy) as opposed to SFTRT (P = 0.06 and P = 0.10, respectively). The improvement in survival associated with AHTRT (with or without chemotherapy) was statistically significant for the subgroup of patients with nonsquamous cell carcinoma after adjustment for other potentially confounding factors (P = 0.02). No differences in freedom from systemic progression or survival were found in a comparison of AHTRT with chemotherapy and AHTRT without chemotherapy. CONCLUSIONS: These results suggest that treatment of Stage IIIA or IIIB nonsmall cell lung carcinoma with AHTRT with or without chemotherapy may improve freedom from local progression and survival as compared with SFTRT, especially for patients with nonsquamous cell carcinoma. The statistical powers to detect the observed differences in median time to local progression and survival were approximately 55% and 35%, respectively. Therefore, further investigation comparing SFTRT with AHTRT is warranted. 相似文献
926.
LD Mastrandrea EM Kasperek EG Niles CM Pickart 《Canadian Metallurgical Quarterly》1998,37(27):9784-9792
The mammalian ubiquitin conjugating enzyme known as E2-25K catalyzes the synthesis of polyubiquitin chains linked exclusively through K48-G76 isopeptide bonds. The properties of truncated and chimeric forms of E2-25K suggest that the polyubiquitin chain synthesis activity of this E2 depends on specific interactions between its conserved 150-residue core domain and its unique 50-residue tail domain [Haldeman, M. T., Xia, G., Kasperek, E. M., and Pickart, C. M. (1997) Biochemistry 36, 10526-10537]. In the present study, we provide strong support for this model by showing that a point mutation in the core domain (S86Y) mimics the effect of deleting the entire tail domain: the ability to form an E2 approximately ubiquitin thiol ester is intact, while conjugation activity is severely inhibited (>/=100-fold reduction in kcat/Km). The properties of E2-25K enzymes carrying the S86Y mutation indicate that this mutation strengthens the interaction between the core and tail domains: both free and ubiquitin-bound forms of S86Y-25K are completely resistant to tryptic cleavage at K164 in the tail domain, whereas wild-type enzyme is rapidly cleaved at this site. Other properties of S86Y-26K suggest that the active site of this mutant enzyme is more occluded than the active site of the wild-type enzyme. (1) Free S86Y-25K is alkylated by iodoacetamide 2-fold more slowly than the wild-type enzyme. (2) In assays of E2 approximately ubiquitin thiol ester formation, S86Y-25K shows a 4-fold reduced affinity for E1. (3) The ubiquitin thiol ester adduct of S86Y-25K undergoes (uncatalyzed) reaction with dithiothreitol 3-fold more slowly than the wild-type thiol ester adduct. One model to accommodate these findings postulates that an enhanced interaction between the core and tail domains, induced by the S86Y mutation, causes a steric blockade at the active site which prevents access of the incoming ubiquitin acceptor to the thiol ester bond. Consistent with this model, the S86Y mutation inhibits ubiquitin transfer to macromolecular acceptors (ubiquitin and polylysine) more strongly than transfer to small-molecule acceptors (free lysine and short peptides). These results suggest that unique residues proximal to E2 active sites may influence specific function by mediating intramolecular interactions. 相似文献