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991.
A study was designed to simulate the repair of an indirect resin composite restoration with conventionally cured resin composite. Two-part specimens were prepared to test the diametral tensile strength of the repair interface between the base material of an indirectly cured resin composite (Herculite XRV) and repairs carried out with three directly cured materials (Herculite XRV, TPH, and Charisma). The repairs were carried out with and without use of the bonding resin for the repair material. The diametral tensile strengths of all repaired specimens were significantly less than those of bulk unrepaired specimens. There were no significant differences between the diametral tensile strengths of repaired blocks when the repair materials were used without bonding resin. The use of an intermediate layer of bonding resin significantly increased the bond strengths obtained when Herculite XRV and TPH were used for repair. There was no significant difference between the strength values of Herculite XRV and TPH, but Charisma exhibited the lowest strengths of repaired specimens. 相似文献
992.
BI Freedman CH Wilson BJ Spray AB Tuttle IM Olorenshaw GM Kammer 《Canadian Metallurgical Quarterly》1997,29(5):729-732
The factors that determine a patient's susceptibility to specific target organ involvement in systemic lupus erythematosus (SLE) remain unknown. Lupus nephritis can be a particularly devastating complication, with an increased mortality and the risk of progressive renal damage resulting in end-stage renal disease (ESRD). This analysis was performed to determine whether renal disease aggregated in select families or was a sporadic complication in patients with SLE. We compared the family history of ESRD in 50 patients with SLE complicated by lupus nephritis with 37 controls who had SLE but lacked nephritis after a mean follow-up duration of more than 11 years. The frequency of relatives with ESRD in the lupus nephritis cases was compared with that in controls using Fisher's exact test (significance at P < or = 0.05). Fifty percent (25) of the 50 lupus nephritis patients were black and 50% (25) white, in contrast to 35% (13) and 65% (24) of the 37 lupus non-nephropathy controls, respectively. A first-, second-, or third-degree relative with ESRD was present in 16% (eight) of the 50 lupus nephritis cases and in 0% of the 37 SLE non-nephropathy controls (P = 0.019, Fisher's exact test, two-tail). Twenty-eight percent (seven) of the 25 black patients with lupus nephritis had relatives with ESRD compared with 0% of the 13 black lupus non-nephritis controls (P = 0.07). Only one of the eight relatives with ESRD had SLE or a collagen vascular disease. Lupus nephritis patients and the non-nephritis controls had similar ages (mean +/- SD: 38.5 +/- 10.0 years v 46.6 +/- 11.8 years; P = 0.28), family sizes (6.27 +/- 2.61 first-degree relatives v 6.35 +/- 3.25 first-degree relatives; P = 0.16), and duration of SLE (9.26 +/- 5.94 years v 11.35 +/- 6.43 years; P = 0.60). Familial clustering of ESRD was observed in black patients with SLE who had nephritis. This was unlikely to be related to differences in patient age, family size, or duration of SLE. This data, coupled with the known familial aggregation of ESRD in blacks with hypertensive and diabetic ESRD, supports the contention that genetic factors contribute to the familial clustering. The presence of relatives with etiologies of ESRD other than SLE suggests that there is an inherited susceptibility to progressive renal failure, independent of the etiology of ESRD. 相似文献
993.
994.
A variable-pressure scanning electron microscope (VP-SEM) equipped with a high-sensitive backscattered electron (BSE) detector of the YAG type was applied to studies of biological tissue samples. The rat kidney and trachea were fixed, dehydrated in ethanol, critical point-dried and examined in the VP-SEM under a specimen chamber pressure of 1 to 150 Pa. The high-resolution surface images of the non-coated specimens were obtained in a low-vacuum (1-20 Pa) environment at an accelerating voltage of 5 kV, while the images at 10-20 kV contained information beneath the surface of the specimens. The observation in the VP-SEM equipped with YAG detector in a low-vacuum (1-20 Pa) environment at low (3-5 kV) accelerating voltages is useful for the three-dimensional analysis of the surface morphology of biological non-coated samples. 相似文献
995.
996.
GD Williams A Numa J Sokol V Tobias BJ Duffy 《Canadian Metallurgical Quarterly》1998,24(10):1089-1092
OBJECTIVES: To investigate the value of extracorporeal circulatory life support (ECLS) in paediatric patients with severe Bordetella pertussis infection. DESIGN: Single case report and a review of the ECLS database. SETTING: Tertiary referral hospital paediatric intensive care unit. PATIENTS AND PARTICIPANTS: A single case report of an infant with B. pertussis infection is described. Despite receiving ECLS, this infant died from overwhelming cardiac and cerebral insults. Outcome for children receiving ECLS registered on the Extracorporeal Life Support Organization database is reviewed. MEASUREMENTS AND RESULTS: The mortality of infants receiving ECLS for B. pertussis infection is high, with only 5 survivors reported among 22 registered cases. The majority of nonsurvivors had evidence of circulatory collapse in addition to severe respiratory failure, and these patients commonly died of hypoxic-ischaemic cerebral insult. These data suggest the existence of a subgroup of patients with respiratory failure only, who may benefit from ECLS, and a larger subgroup who suffer ischaemic cardiac and cerebral insults which are unlikely to be improved by ECLS. CONCLUSIONS: The value of ECLS in patients with B. pertussis infection who present with major cardiac dysfunction is questionable. Such patients almost invariably have a poor outcome despite maximal therapy. 相似文献
997.
JM Schulte BJ Nolt RL Williams CL Spinks JJ Hellsten 《Canadian Metallurgical Quarterly》1998,280(5):439-442
Documentation and measurement of intraoperative cerebral blood flow during various neurosurgical procedures is not only valuable but also very informative. There are various methods by which qualitative and quantitative measurement of blood flow have been developed over the years. The use of perivascular ultrasonic flow more recently is fast gaining popularity. We describe the technique, principle and application of ultrasonic perivascular micro-flow probe quantitative measurement of selective vessel flow in neurosurgery. 相似文献
998.
BJ Bolwell M Kalaycio M Goormastic R Dannley SW Andresen A Lichtin B Overmoyer B Pohlman 《Canadian Metallurgical Quarterly》1997,20(9):761-765
A major limitation of ABMT for relapsed/refractory Hodgkin's disease is disease recurrence post-transplantation. We retrospectively reviewed 68 patients undergoing ABMT from January 1987 to June 1993. All received a uniform preparatory regimen (CBV). The median patient age was 30; 75% received prior radiation therapy and all patients received prior chemotherapy. Thirty-one percent presented at the time of transplantation with tumor masses larger than 10 cm. Sixty-two percent received autologous marrow alone and 38% PBPC with or without autologous bone marrow. Overall and progression-free survival are 43 and 36% at 5 years. Median follow-up for survivors is 59 months. Multivariate analysis revealed that tumor bulk was the most powerful poor prognostic factor for both survival and progression-free survival. Those transplanted with non-bulky tumors had an overall survival and progression-free survival of 52 and 44%, respectively, compared to those transplanted with bulky tumors who had an overall survival and progression-free survival of 22 and 16% (P = 0.03 and P = 0.04, respectively). Twenty-seven patients have relapsed. Four relapsed more than 2 years after ABMT. Four of the 27 patients who have relapsed remain alive, two without evidence of disease. The time after transplant to relapse was prognostically important, with no patients who relapsed within 6 months of ABMT still being alive, compared with 25% of patients who relapsed 7 or more months after ABMT who are still alive. We conclude that salvage therapy for relapse after ABMT is appropriate, as some patients may achieve prolonged survival. The time from transplant to relapse is an important survival predictor. 相似文献
999.
Treatment of urinary incontinence in homebound older adults: interface between research and practice
S Engberg BJ McDowell N Donovan I Brodak E Weber 《Canadian Metallurgical Quarterly》1997,43(10):18-22, 24-6
Urinary incontinence is one of the most common problems afflicting older adults and a major contributor to healthcare costs for homebound older individuals. The authors conducted a randomized controlled clinical study examining the effectiveness of biofeedback-assisted pelvic floor muscle training and prompted voiding in treating urinary incontinence in homebound older adults. This article briefly describes the assessment and treatment protocols utilized during this study and describes their subsequent application to clinical practice within a large urban home health agency. 相似文献
1000.
The symptoms of temporomandibular dysfunction (TMD), reported by 705 female university students of Riyadh, Saudi Arabia, are analysed. The population is representative of the educated class of Saudi Arabia. The most frequently reported symptoms were jaw feeling tired (34.5%), awareness of uncomfortable bite (31.3%), pain in front of the ear (22.4%) and discomfort upon wide opening (22.4%). The frequency of subjective reactions was, pain interferes with activity (42%), disturbed sleep (40.6%), taking of medication (27.8%) and pain being frustrating or depressing (26.8%). Some interesting relationships were found between the reported symptoms and marital status, residence and college of education. These findings are similar to those reported in a Bedouin community in Egypt, but lower than that in a Saudi Arabian population attending dental clinics, Saudi male dental students and high school students. 相似文献