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61.
Renal transplantation in adults with thrombotic thrombocytopenic purpura/haemolytic-uraemic syndrome
PJ Conlon DC Brennan WW Pfaf WF Finn T Gehr RR Bollinger SR Smith 《Canadian Metallurgical Quarterly》1996,11(9):1810-1814
BACKGROUND: Thrombotic thrombocytopenic purpura/haemolytic-uraemic syndrome (TTP/HUS) is a rare cause of renal failure in adults. There is little data concerning the outcome of adult patients who receive a renal transplant for TTP/HUS: METHODS: We have carried out a survey of 22 transplant centres in the USA to determine the outcome of patients who developed ESRD from TTP/HUS and latter received a renal transplant. RESULTS: Twelve of the 22 centres responded to our inquiry. Seven centres had not transplanted any patients with TTP/HUS, and five centres had transplanted a total of 24 grafts in 17 patients with TTP/HUS: Thirty-three per cent of patients demonstrated definite clinical and pathological evidence of recurrence of TTP/HUS: An additional 16% of patients demonstrated pathological evidence of possible recurrence of TTP/HUS in the absence of clinical manifestations. The overall 1-year graft survival rate was 42% and the 2-year graft survival rate was 35%. In our experience recurrence TTP/HUS was associated with universal graft failure. Although cyclosporin A does occasionally cause a thrombotic angiopathy in patients with no history of TTP/HUS, we found no evidence that it should be avoided in patients with a previous history of ESRD from TTP/HUS who subsequently receive a renal transplant. CONCLUSIONS: TTP/HUS frequently recurres in adults who receive a renal transplant, with a 2-year graft survival rate of 35%. 相似文献
62.
MJ Greenberger RM Strieter SL Kunkel JM Danforth LL Laichalk DC McGillicuddy TJ Standiford 《Canadian Metallurgical Quarterly》1996,173(1):159-165
The role of macrophage inflammatory protein-2 (MIP-2) in bacterial pneumonia was characterized. Mice were challenged with Klebsiella pneumoniae intratracheally, and organs were harvested at 8, 24, and 48 h. Inoculation with K. pneumoniae resulted in the time-dependent expression of MIP-2 mRNA and protein within the lung, which was maximal 48 h after inoculation. Mice were then passively immunized with rabbit anti-murine MIP-2 serum intraperitoneally 2 h before administration of K. pneumoniae. Treatment with anti-MIP-2 serum resulted in a 60% decrease in lung neutrophil (PMNL) influx and a significant increase in K. pneumoniae colony-forming units in both lung and liver homogenates. Finally, treatment with anti-MIP-2 serum decreased early (48-72 h) but not late (after 72 h) survival in animals with Klebsiella pneumonia. This study indicates that MIP-2 is produced during Klebsiella pneumonia and inhibition of MIP-2 bioactivity in vivo results in decreased PMNL influx and lung bacterial clearance in murine Klebsiella pneumonia. MIP-2 is produced during Klebsiella pneumonia and inhibition of MIP-2 bioactivity in vivo results in decreased PMNL influx and lung bacterial clearance in murine Klebsiella pneumonia. 相似文献
63.
JW Cohen AC Monheit KM Beauregard SB Cohen DC Lefkowitz DE Potter JP Sommers AK Taylor RH Arnett 《Canadian Metallurgical Quarterly》1996,33(4):373-389
This article describes the Medical Expenditure Panel Survey (MEPS), the third in a series of nationally representative surveys of medical care use and expenditures sponsored by the Agency for Health Care Policy and Research. The MEPS is designed to provide extensive data on the types of health care services American use, how frequently they use them, how much is paid for the services, and who pays for them. It also will provide information on the types and costs of private health insurance available to the U.S. population. The survey is unparalleled in its degree of detail, as well as its ability to link medical care use, payments, and health insurance coverage to specific survey respondents and their families. It allows analysts to examine how individual and family characteristics, including the characteristics of their health insurance, affect medical care use and spending. This article discusses each of the MEPS components, focusing on design enhancements that have been made since the survey was last conducted nearly a decade ago. 相似文献
64.
GK Bejjani B Sullivan E Salas-Lopez J Abello DC Wright A Jurjus LN Sekhar 《Canadian Metallurgical Quarterly》1998,43(4):842-52; discussion 852-3
INTRODUCTION: The infratemporal fossa (ITF) gives passage to most major cerebral vessels and cranial nerves. Dissection of the ITF is essential in many of the lateral cranial base approaches and in exposure of the high cervical internal carotid artery (ICA). We reviewed the surgical anatomy of this region. METHODS: Direct foraminal measurements were made in seven dry skulls (14 sides), and the relationship of these foramina to each other and various landmarks were determined. Ten ITF dissections were performed using a preauricular subtemporal-infratemporal approach. Preliminary dissections of the extracranial great vessels and structures larger than 1 cm were performed using standard macroscopic surgical techniques. Dissection of all structures less than 1 cm was conducted using microsurgical techniques and instruments, including the operating microscope. The anatomic relationships of the muscles, nerves, arteries, and veins were carefully recorded, with special emphasis regarding the relationship of these structures to the styloid diaphragm. The dissection was purely extradural. RESULTS: The styloid diaphragm was identified in all specimens. It divides the ITF into the prestyloid region and the retrostyloid region. The prestyloid region contains the parotid gland and associated structures, including the facial nerve and external carotid artery. The retrostyloid region contains major vascular structures (ICA, internal jugular vein) and the initial exocranial portion of the lower Cranial Nerves IX through XII. Landmarks were identified for the different cranial nerves. The bifurcation of the main trunk of the facial nerve was an average of 21 mm medial to the cartilaginous pointer and an average of 31 mm medial to the tragus of the ear. The glossopharyngeal nerve was found posterior and lateral to stylopharyngeus muscle in nine cases and medial in only one. The vagus nerve was consistently found in the angle formed posteriorly by the ICA and the internal jugular vein. The spinal accessory nerve crossed anterior to the internal jugular vein in five cases and posterior in another five cases. It could be located as it entered the medial surface of the sternocleidomastoid muscle 28 mm (mean) below the mastoid tip. The hypoglossal nerve was most consistently identified as it crossed under the sternocleidomastoid branch of the occipital artery 25 mm posterior to the angle of the mandible and 52 mm anterior and inferior to the mastoid tip. CONCLUSION: The styloid diaphragm divides the ITF into prestyloid and retrostyloid regions and covers the high cervical ICA. Using landmarks for the exocranial portion of the lower cranial nerves is useful it identifying them and avoiding injury during approaches to the high cervical ICA, the upper cervical spine, and the ITF. 相似文献
65.
A high-speed imaging technique was used to investigate the effects of inhibitors and activators of protein kinase C (PKC) on the [Ca2+]i transients and contraction of fura-2 loaded rat ventricular cardiac myocytes. The amplitude of the [Ca2+]i transient was reduced following treatment with 100 nM phorbol 12,13-dibutyrate (PDBu), whereas the PKC inhibitors staurosporine (0.5 microM) and calphostin C (10 microM) increased [Ca2+]i transient amplitude, elevated basal [Ca2+]i and slowed the decay of the [Ca2+]i transient. These changes were paralleled by similar alterations in the rate and extent of cell shortening. The activity of nitrendipine-sensitive Ca2+ channels was monitored indirectly as the rate of Mn2+ quench of cytosolic fura-2 in electrically-paced cells. PDBu reduced Mn2+ influx by six-fold, whereas staurosporine and calphostin C increased the influx rate by eight-fold and seven-fold over basal quench, respectively. The caffeine releasable Ca2+ pool was reduced in the presence of PDBu and increased transiently in presence of staurosporine. The effects of PKC activation and inhibition on sarcoplasmic reticulum Ca2+ content may be secondary to alterations of sarcolemmal Ca2+ influx. However, the PKC inhibitors also decreased the rate of sarcoplasmic reticulum Ca2+ uptake in permeabilized myocytes, suggesting that a direct effect of PKC on the sarcoplasmic reticulum may contribute to the prolongation of the [Ca2+]i transient under these conditions. The present work demonstrates that basal PKC activity has a potent depressant effect, mediated primarily through inhibition of sarcolemmal Ca2+ influx, which may play a key role in setting the basal tone of cardiac muscle. 相似文献
66.
DC Broering JR Izbicki C Bloechle R Maas CF Eisenberger CE Broelsch 《Canadian Metallurgical Quarterly》1998,69(8):877-879
Twenty-seven painful knee replacements were evaluated arthroscopically. The diagnostic and therapeutic value of these arthroscopic procedures was studied retrospectively. In 5 of the 27 cases, the arthroscopy revealed no diagnosis for the pain. Some form of arthroscopic treatment was performed in 20 cases; in 6 of these 20 cases, however, the treatment did not reduce the pain. Based on these findings, we conclude that the indications for arthroscopic evaluation and treatment of painful knee prostheses are limited. 相似文献
67.
J Bukh CL Apgar R Engle S Govindarajan PA Hegerich R Tellier DC Wong R Elkins MC Kew 《Canadian Metallurgical Quarterly》1998,178(4):1193-1197
Six major genotypes (genotypes 1-6) of hepatitis C virus (HCV) have been identified. These genetic variants are being transmitted to chimpanzees, the only recognized animal model for the study of HCV. Genotype 5a (strain SA13), a variant found primarily in South Africa, has been transmitted to chimpanzees for the first time. Experimental infection of 2 chimpanzees was characterized by early appearance of viremia and peak virus titers of 10(5)-10(6) genome equivalents/mL. The HCV infection was resolved by week 15 after inoculation in 1 chimpanzee and persisted in the other. Both chimpanzees became anti-HCV-positive by week 14 after inoculation. Both chimpanzees developed viral hepatitis. The infectivity titer of a genotype 5a challenge pool prepared from the first passage of HCV in a chimpanzee was approximately 10(4) infectious doses/mL. Finally, sequence analysis of strain SA13 confirmed that genotype 5a is genetically distinct from other genotypes of HCV. 相似文献
68.
69.
The maturational status of Adelta and C-fibers in the fetal rat spinal cord was examined using formalin-induced c-fos expression as a marker for neuronal activities. Awake 19-, 20-, and 21-day fetuses (FD) were injected ex utero with 5 microl of 10% formalin either into the ventral aspect of the forepaw or the hindpaw. FD 19 fetuses showed little response to the injection, but with increasing age, the fetuses exhibited more specific behaviors following injury of the paw. By FD 21, fetuses treated with formalin injection showed body curls and twitches, mouth opening, face wiping, and withdrawal of the injected paw. The anatomical data paralleled that of behavior; FD 19 animals expressed a small number of Fos labeled nuclei following the formalin injection that was not statistically different from control animals. The formalin-induced increase in Fos staining was first observed at FD 20 with a large increase in the number of Fos labeled cell occurring between FD 20 and 21. By FD 21, the pattern of Fos stained nuclei resembled that found in neonatal rats. There was constitutive bilateral staining in all untreated, saline and formalin injected fetuses that is unique to prenatal animals. Formalin treated fetuses showed constitutive level of staining in addition to the increase in the c-fos expression caused by formalin. We have thus demonstrated that, as indexed both by behavioral response and by Fos immunoreactivity, rat fetuses are capable of transmitting and responding to noxious input before birth. 相似文献
70.
MP Saunders AJ Salisbury KJ O'Byrne L Long RM Whitehouse DC Talbot EB Mawer AL Harris 《Canadian Metallurgical Quarterly》1997,82(12):4044-4048
The treatment of cancer patients with conventional chemotherapy is sometimes associated with severe systemic toxicity and only a minimal survival benefit. Because of this, new less toxic and more efficacious treatments have been sought. 8-Chloro-cAMP (8-Cl-cAMP) is one of a new generation of anticancer drugs that act at the level of signal transduction. In preclinical models, 8-Cl-cAMP modulates protein kinase A (PKA) leading to growth inhibition and increased differentiation of cancer cells. 8-Cl-cAMP was given to 16 patients with advanced cancer as an infusion via an indwelling subclavian venous catheter. We showed that 8-Cl-cAMP had a parathyroid hormone-like effect leading to increased synthesis of renal 1,25-dihydroxyvitamin D [up to 14 times the baseline value, median 3.6 times; P = 0.00001 (Student's paired t test)]. This produced the dose-limiting toxicity of reversible hypercalcemia that could not be controlled by the administration of either pamidronate or dexamethasone. The treatment was otherwise well tolerated, and other cAMP-dependent pathways (cortisol and TSH) were not affected, emphasizing the marked differences between organs in their sensitivity to this cAMP analog. Our results have shown that 8-Cl-cAMP is biologically active, and it is feasible that if the hypercalcemia can be controlled, then this drug may have a role as a single agent, or as a short infusion between cycles of chemotherapy. 相似文献