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941.
5- and 6-O-(Fluoresceinylmethyl)hydroxylamine (OFMHA, 5a, b) were prepared from the corresponding bis-pivaloyl-protected hydroxymethylfluoresceins (1a, b) in 50-70% yield. The hydroxylamine derivatives reacted smoothly with the abasic sites present in acid/heat stressed calf thymus DNA. 相似文献
942.
LE Ramirez MI Machado PG Maywald A Matos E Chiari EL Silva 《Canadian Metallurgical Quarterly》1998,31(1):99-102
Coccidiomycosis is a fungal infection that primarily causes pulmonary disease. Extrapulmonary dissemination can occur to the musculoskeletal system with the knee joint most frequently involved. This case report describes a patient with coccidiomycosis whose initial presentation was of a popliteal cyst. The need for aggressive surgical and antibiotic treatment to eradicate this infection is discussed. Coccidiomycosis should be considered in a differential diagnosis of patients with popliteal cysts without other obvious etiologies. 相似文献
943.
OBJECTIVE: To identify the vascular supply and resorption/formation activity of the humerus of pigeons. DESIGN: Pigeons were injected with the fluorochrome label oxytetracycline and, 5 days later, with the label calcein. 5 days after administration of the second fluorochrome, a wing from each bird was infused with a microparticle barium solution immediately after euthanasia and the chosen humerus was prepared for angiography while the opposite was prepared for histomorphometry. ANIMALS: 17 nine-month-old pigeons, consisting of 9 male and 8 female birds. PROCEDURE: At euthanasia, 1 wing was chosen for infusion and the barium solution was injected through a catheter in the brachiocephalic artery. Both humeruses were harvested. The infused humerus was decalcified, radiographed, and sectioned for H&E staining. The opposite humerus was sectioned and measured by use of a morphometric analyzing system to determine cross-sectional area, endosteal and periosteal perimeters, and percentage of perimeter containing a single and/or double label. RESULTS: All pigeons had an intramedullary arterial supply. The bones had a quiescent appearance histologically, consisting principally of lamellar bone with few osteospecialized cells, resorption surfaces, or osteons. Less than 10% of either the periosteal or endosteal surface acquired a fluorochrome label. CONCLUSIONS: The intramedullary vascular supply of the humerus is similar in structure to the vascular supply to mammalian bones. The humerus is, however, a quiescent bone in the sexually mature pigeon, with little remodeling activity present. CLINICAL RELEVANCE: The intramedullary blood supply may have an important role in the healing of humeral fractures in avian species. 相似文献
944.
Clones of an African cassava mosaic virus isolate originating from Nigeria (ACMV-NOg) were shown to be infectious to cassava by biolistic inoculation. The production of pseudorecombinants between ACMV-NOg and clones of an ACMV isolate originating from Kenya (ACMV-K) indicated that the lack of infectivity of ACMV-K to cassava was due to defect(s) in the DNA B genomic component; this component encodes two proteins involved in cell-to-cell movement. This is the first demonstration of infectivity of a cloned geminivirus to cassava and conclusively proves that ACMV is the causative agent of cassava mosaic disease. The potential uses of infectious ACMV clones and the means by which to introduce them into cassava are discussed. 相似文献
945.
RD Hughes N Nicolaou PG Langley AJ Ellis JA Wendon R Williams 《Canadian Metallurgical Quarterly》1998,22(10):854-858
Multiple organ failure frequently occurs in patients with acute liver failure, and this has been associated with increased cytokine production. Treatment by hemoperfusion with an extracorporeal liver assist device (ELAD) containing human liver-derived cells was performed in 12 patients with acute liver failure. Over the first 6 h, there were significant increases in plasma tumor necrosis factor alpha (TNFalpha; from 114+/-54 pg/ml [mean+/-SEM] to 236+/-161 pg/ml, p < 0.05) and interleukin (IL)-6 (260+/-121 pg/ml to 445+/-149 pg/ml, p < 0.05) but not in interferon gamma (IFNgamma). A similar pattern with a small peak increase was observed for complement C5b-9 complex. Plasma C-reactive protein (CRP) and thrombin antithrombin (TAT) III complex showed small peaks after 24 h of ELAD hemoperfusion. No such changes were seen in 12 control patients with acute liver failure who were treated with intensive care alone. These transitory effects, without changes in blood pressure, are likely to be due to the contact of the blood with the dialyzer membrane. There was no evidence of the clearance of cytokines by the ELAD. 相似文献
946.
Summary The process of preparing and publishing the Indian Standards is very elaborate and aims at having opinions from research institutions,
users, manufacturers and service organisations. This should ensure that the standards are quoted and followed extensively.
However, this is not seen to happen atleast in NDT field. Need to have an open debate as to what are the courses of user’s
indifference to IS standards is emphasised.
Various probable reasons are examined in the paper with examples from IS and other standards. The more likely of the causes
seen to be that (i) the user prefers a format of a comprehensive code which guides him about acceptance levels and other related
aspects, (ii) more faith in background database behind the foreign standards and (iii) causeless indifference. The lesser
important reasons are also discussed. Certain suggestions are made about the publication format. 相似文献
947.
PG Burkard 《Canadian Metallurgical Quarterly》1998,2(4):398-409
In the past two decades, there have been tremendous changes in the understanding and therapy of acid-peptic diseases. Currently there are many new and effective approaches to the treatment of dyspeptic symptoms and the ulcerative and erosive diseases of the upper gastrointestinal tract. Application of an appropriate therapeutic strategy requires understanding of the pathophysiology of the disease process as well as the pharmacology of the available medications. In general, medications to neutralize gastric acid or suppress acid secretion are selected relative to the severity of the acid-mediated injury. Antacids are ideal for suppression of sporadic symptoms. H2-receptor antagonists are useful for the treatment of dyspepsia or uncomplicated ulcers. For the most severe injuries, proton pump inhibitors provide both relief of symptoms and healing of damaged mucosa. 相似文献
948.
R Hertan PG Farnworth KL Fitzsimmons DM Robertson 《Canadian Metallurgical Quarterly》1999,140(1):6-12
BACKGROUND AND OBJECTIVE: The clinical picture, response to therapy, and prognosis of women with diffuse malignant peritoneal mesotheliomas (DMPM) are ill defined. The purpose of this study is to report on the clinical picture, response to therapy, and survival of women with DMPM. METHODS: The study is a retrospective review of 15 women with the confirmed pathologic diagnosis of DMPM treated between 1964 and 1996. Survival curves were constructed according to the Kaplan-Meier method. The effect of different factors on survival was studied using the log-rank test. Two-tailed P values < 0.05 were considered significant. RESULTS: Clinical features included abdominal distension (11/15, 73%), abdominal pain (6/15, 40%), ascites (9/15, 60%), abdominal or pelvic masses (14/15, 93%), elevated CA-125 (4/4, 100%), thrombocytosis (4/ 15, 27%), and thrombo-embolic manifestations (3/15, 20%). The response rate to all first-line chemotherapy regimens was 30%. The response rate to paclitaxel/cisplatin was 66.7% and the toxicity was tolerable. The median survival of all patients was 12.5 months. Patients who underwent cytoreductive surgery survived longer than those who underwent biopsy only (median survival 13.5 vs. 6.0 months, P = 0.24). Patients who received chemotherapy survived significantly longer than those who did not receive chemotherapy (29.0 vs. 1.0 months, P = 0.03). Patients who responded to first-line chemotherapy survived significantly longer than those who did not respond (P = 0.04). CONCLUSIONS: Cytoreductive surgery and chemotherapy, especially with paclitaxel and cisplatin, might be of benefit in women with DMPM. 相似文献
949.
Facial paralysis is a potentially devastating disorder with numerous implications. Multiple entities must be considered in its etiology, and recent advances in microbiology, radiographic imaging, electrodiagnostic testing, and microsurgery have provided great insight into the pathophysiology, diagnosis, treatment, and rehabilitation of the facial nerve. Recent DNA PCR testing has shed new insight into the potential cause for Bell's palsy. This article focuses on the evaluation, differential diagnosis, medical treatment, and rehabilitation of facial nerve pathology with primary emphasis on facial paralysis. Surgical management is also discussed, including reanimation of the paralyzed face. 相似文献
950.