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991.
KS Kornman A Crane HY Wang FS di Giovine MG Newman FW Pirk TG Wilson FL Higginbottom GW Duff 《Canadian Metallurgical Quarterly》1997,24(1):72-77
OBJECTIVE: To determine whether it is possible to predict the presence of bladder outlet obstruction (BOO) by non-invasive clinical variables in patients with lower urinary tract symptoms (LUTS) suggestive of BOO. PATIENTS AND METHODS: Patients with LUTS suggestive of BOO were entered into a prospective protocol evaluating the International Prostate Symptom Score (IPSS), prostate size, non-invasive uroflow, post-void residual urine volume (PVR) and a pressure flow study. Only patients with a maximum flow rate (Qmax) of < or = 15 mL/s and an IPSS > or = 7 were included. The study comprised 253 patients; the degree of obstruction was correlated to several non-invasive clinical variables. Subsequently nomograms were developed by multiple logistic regression analysis to obtain the probability of BOO in patients with LUTS. RESULTS: Prostate volume, Qmax, PVR and voided volume correlated significantly with the degree of BOO rated according to the linear passive urethral resistance relation (linPURR). In contrast, there was no such correlation for the IPSS and the quality-of-life question of the IPSS. The percentage of patients with BOO defined by a linPURR of 3-6 decreased from 85% in those with a Qmax of 0-5 mL/s to 60% (Qmax 6-10 mL/s) and 44% (Qmax 11-15 mL/s). In parallel, the percentage of patients with BOO increased from 53% of those with a prostate volume of < or = 50 mL, to 79% of those with prostates of 51-100 mL and 75% of those > 100 mL. Based on Qmax, PVR and prostate volume, nomograms were established by multiple logistic regression analysis for the probability of BOO in patients with LUTS. CONCLUSION: The nomograms presented herein should help the clinician to identify patients with LUTS who should undergo pressure flow studies before surgical intervention to detect the presence of obstruction and in whom these studies can be safely spared. 相似文献
992.
JS Kim NL Müller CS Park DA Lynch LS Newman P Grenier CJ Herold 《Canadian Metallurgical Quarterly》1997,21(2):306-311
PURPOSE: Our goal was to measure normal bronchial to accompanying pulmonary arterial diameter ratios and normal bronchial wall thickness on thin section CT at high altitude and at sea level. METHOD: Seventeen normal, healthy, nonsmoking subjects living at 1,600 m altitude and 16 living at sea level underwent thin section CT (1.5 to 2.0 mm collimation). All images were photographed at window levels of -450 and -700 HU and window width of 1,500-1,600 HU. Internal diameters of the segmental and subsegmental bronchi were measured and compared with the diameter of the adjacent pulmonary artery. Bronchial wall thickness of each bronchus was measured. Only bronchi and arteries seen in cross section and within 1 mm from each other were included in the analysis. RESULTS: Four hundred sixty-seven bronchi (215 at high altitude, 252 at sea level) were assessed. At window level of -450 HU, the bronchoarterial ratio was 0.76 +/- 0.14 (mean +/- SD) at altitude and 0.62 +/- 0.13 at sea level (p < 0.001). Bronchial wall thickness measured 0.92 +/- 0.09 mm (mean +/- SD) at altitude and 1.12 +/- 0.19 mm at sea level (p < 0.001). At window level of -700 HU, there was an artifactual decrease in the bronchoarterial diameter ratios and an increase in bronchial wall thickness. CONCLUSION: Bronchoarterial ratio increases and bronchial wall thickness decreases with altitude. These findings are presumably related to hypoxic bronchodilatation and vasoconstriction. 相似文献
993.
ME Brier H Bays R Sloan DJ Stalker I Welshman GR Aronoff 《Canadian Metallurgical Quarterly》1997,29(6):907-911
There is considerable controversy about the distal clearance margin that needs to be maintained beyond the extent of a rectal tumor in order to reduce the risk of local recurrence. We investigated the rate of local recurrence, distant metastases and survival in 87 patients who had undergone radical restorative resection of the rectum for cancer and had been followed up for a median period of over 6 years, and we analyzed the statistical relation (log-rank test for trend) with the length of the distal margin. The distal margin length was divided into three categories: 1 cm, 2 cm, and > or = 3 cm. No significant correlation was found between the length of the distal clearance margin and the oncologic outcome. Taken together, our data suggest that if the resection line distally falls on healthy tissue, there is no need to resect additional rectum in order to achieve a better outcome. 相似文献
994.
SM Walpole A Nicolaou GR Howell A Whittaker DR Bentley MT Ross JR Yates D Trump 《Canadian Metallurgical Quarterly》1997,44(3):300-308
Treatment of a skeletodental Class II vertical growth problem, combined with a severe arch length deficiency in both arches, presents a challenging orthodontic problem. This is the case report of a small-statured, 11-year, 10-month-old boy with a history of juvenile chronic arthritis and marked mandibular retrognathia who was treated with first premolar extractions in both arches. Unexpected favorable growth, with significant decrease of the mandibular plane angle over a long treatment period, provided a very satisfactory result. [This case report was presented to the American Board of Orthodontics in partial fulfillment of the requirements for the certification process.] 相似文献
995.
TE Rohan TG Hislop GR Howe RP Gallagher CZ Teh P Ghadirian 《Canadian Metallurgical Quarterly》1997,6(4):382-388
The relationship between cigarette smoking and risk of prostate cancer was examined in a case-control study conducted in Ontario and British Columbia, Canada. In each centre, cases were men with a histologically confirmed diagnosis of adenocarcinoma of the prostate notified to the provincial cancer registry. In Ontario, controls were selected randomly from assessment lists maintained by the Ontario Ministry of Revenue and were frequency matched to the cases on age. In British Columbia, controls were also frequency matched to the cases on age and were selected randomly from a roster maintained by the Medical Services Plan of British Columbia. The study in Ontario was conducted between April 1990 and April 1992, and that in British Columbia was conducted between January 1989 and December 1991. In all, the study included 408 cases (207 in Ontario and 201 in British Columbia) and 407 controls (207 in Toronto and 200 in British Columbia (one case was unmatched). Overall, there was little variation in risk of prostate cancer with pack-years of cigarette consumption (filter and non-filter cigarettes combined), and there was no evidence for an effect confined to filter or non-filter cigarettes. There was some evidence for a positive association with non-filter cigarettes in British Columbia, but on formal testing for heterogeneity, this finding was not inconsistent with the absence of an association in Ontario. There was also little variation in risk by years since first smoked or (for ex-smokers) by years since quitting. These data provide little support for an association between cigarette smoking and prostate cancer risk. 相似文献
996.
Cervical and uterine varices with thrombosis were observed at the necropsy of a virgin 16-year-old Peruvian Paso that had previous episodes of hemorrhage from the uterus. Practitioners and pathologists should be alert to the possibility of ruptured varices in mares with hemorrhage into the uterus or from the vulva. 相似文献
997.
Ultrasound scans were used to study 23 cases of abdominal contusion in children, between January 1992 and December 1993. Thirteen boys and 10 girls were studied. They were all aged between 4 and 14 years, with a mean age of 6 years. The main causes of their injuries were road accidents (12 cases) and play (11 cases). Ultrasound scans were normal in 6 patients and pathological in 17 patients. The most frequently observed injuries were visceral effects (12 cases), almost always associated with hemoperitoneum. In three cases, hemoperitoneum was detected in the absence of visceral effects. The spleen (4 cases) and the liver (4 cases) were the most frequently injured organs. The other injuries detected included renal hematoma, bladder rupture and parietal hematoma. Diagnosis on the basis of ultrasound scans was found to be incorrect in three cases where diagnosis was repeated after the scan. One case involved a blocked perforation of the rectum, one a benign cyst and the other a mesenteric cyst. Despite these misdiagnoses, ultrasound scanning is a highly sensitive and specific method for examination of contusions in children. It is very useful and often sufficient for accurate diagnosis, particularly in units with only modest technical support. 相似文献
998.
Hydromyelia is a dilation of the spinal cord central canal. In man this may be due to congenital malformations such as Dandy-Walker syndrome and Chiari malformations or may be acquired as result of infection, trauma or neoplasia. In dogs hydromyelia may be accidentally diagnosed during routine cisterna magna myelography. Hydromyelia, and its possible etiology, may be confirmed by means of computed tomography or magnetic resonance imaging. Three dogs with hydromyelia due to differing etiologies are described. 相似文献
999.
Bultler Stephen F.; Budman Simon H.; Goldman Risa J.; Newman Frederick J.; Beckley Kristen E.; Trottier Deborah; Cacciola John S. 《Canadian Metallurgical Quarterly》2001,15(1):4
The Addiction Severity Index—Multimedia Version (ASI–MV) is a CD-ROM-based simulation of the interview-administered Addiction Severity Index (ASI). Clients in treatment (N ?=?202) self-administered the ASI–MV to examine the test–retest reliability, criterion validity, and convergent–discriminant validity of the ASI–MV. Excellent test–retest reliability was observed for composite scores and severity ratings. Criterion validity, tested against the interviewer-administered ASI, was good for the composite scores. For severity ratings, variable agreement was observed between the ASI–MV and each interviewer, suggesting poor interrater reliability among interviewers. This conclusion was bolstered by a finding of superior convergent–discriminant validity for both composite scores and severity ratings compared to the standard ASI. The ASI–MV is a viable alternative to the expensive and potentially unreliable interviewer-administered version. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Tamoxifen is an antiestrogen drug widely utilized for the adjuvant hormonal treatment of breast carcinoma. Its use in the primary prophylaxis of this disease is currently being proposed. Although the drug has few side effects, its precise action on breast tissue that has not undergone neoplastic transformation has not been fully elucidated. This prospective, randomized study assessed the estrogen activity of tamoxifen on the mammary gland epithelium of premenopausal patients using a quantitative analysis of mammary epithelium lysosome identified by the cytochemical technique of GOMORI for acid phosphatase and by light microscopy. Tamoxifen significantly increased the number of lysosomes only during the secretory phase of the menstrual cycle. We concluded that the early effect of the drug on normal mammary tissue is synergistic with the effect of estrogen during the premenopausal period. 相似文献