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71.
ML Hawkins JJ Wynn DC Schmacht RS Medeiros TR Gadacz 《Canadian Metallurgical Quarterly》1998,64(6):552-6; discussion 556-7
Changes in the management of trauma over the past few years are significantly affecting postgraduate surgical education, with the lack of operative trauma experience being a major concern in some programs. This problem is accentuated in residency programs that obtain their trauma caseload primarily from blunt injury. Our experience over the past 6 years confirms that the growing trend toward nonoperative management of blunt liver and spleen injuries in adults is likely to exacerbate this problem. Blunt trauma admissions to our Level I trauma center increased from 2888 from 1991 through 1993 (group A) to 3587 from 1994 through 1996 (group B). Liver and/or splenic injuries occurred with equal frequency in both groups. Whereas diagnostic peritoneal lavage was used in 26 per cent of group A, its use dropped to 2 per cent in group B as abdominal computerized tomography was used more frequently to evaluate these patients. Nonoperative management increased from 10 per cent of group A to 54 per cent of group B. As a result, therapeutic laparotomies dropped from 85 in group A (58% of patients with liver/splenic injuries) to 74 (35%) in group B and nontherapeutic laparotomies from 48 (33%) to 23 (11%). While the evolution in the management of blunt liver and splenic injuries has resulted in the avoidance of nontherapeutic laparotomies, the operative caseload available to surgical housestaff has been adversely affected. Although the Residency Review Committee has stressed the importance of the critical care management of these patients, the criteria used to evaluate the number of trauma cases in postgraduate surgical education may need to be revised. 相似文献
72.
RD Howard RS Martens SA Innis JM Drnevich J Hale 《Canadian Metallurgical Quarterly》1998,55(5):1151-1163
A sexual size dimorphism usually occurs when size-dependent reproductive advantages exist in only one sex. Studies on Japanese medaka, Oryzias latipes, have demonstrated reproductive size advantages in females but not in males, even though males and females are similar in body size. We conducted mate-choice and mate-copying tests in which a female could first associate with, then mate with, either a large (>/=1 sd+X standard length) or a small male (=1 sd-X standard length). Large males obtained a mating advantage in both tests, and both mate choice and mate competition influenced their mating success. In the majority of trials, females associated with large males. Association preferences of females corresponded to their mating preferences when mate competition between males was weak; however, when mate competition was strong, large males obtained almost every mating regardless of female association preference. Preference for large males may provide females with a reproductive advantage if males mate multiply because small males become sperm-depleted sooner than large males. We found no indication that females copied the mating decisions of other females. Repeatability of female mating preference was low, not because females mated at random with respect to male size, but because most females consistently preferred large males. We also conducted mating tests at four density levels and found that large males maintained their mating advantage relative to small males at all densities. Thus, male and female medaka may be similar in body size because large size provides a fecundity advantage for females, as demonstrated in previous studies, and large size provides a mating advantage for males, as demonstrated in our study. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour. 相似文献
73.
Competence as communication skills and as skilled practice of asepsis were studied by observing four nurses while interacting with patients and performing intravenous procedures. Nurses were observed using sterile equipment for methods of intravenous therapy. Asepsis is performed frequently, but through misunderstanding in the learning of asepsis or improper model learning the nurses may establish incorrect routines. When performing procedures, unexpected factors can distract both the expert and the inexperienced, resulting in a failure to apply basic aseptic techniques. The nurses showed an interest in the patient by listening and giving responses. Nurses may control interactions with the patient by using undesirable communication skills which include incomplete sentences, incomplete explanations and closed questions. Asked to evaluate their own behavior, the nurses did not estimate whether or not the appropriate skills were applied in observed situations. To improve the quality of nursing care performance it is recommended to further develop and apply skill training programs. 相似文献
74.
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76.
RS Miller DA Weatherford D Stein MM Crane M Stein 《Canadian Metallurgical Quarterly》1994,37(3):442-445
Using capillary videomicroscopy of the nail fold, the frequency of cold-induced vasospasm and capillary hemodynamic parameters were studied after application of cold in 50 patients with primary fibromyalgia, 50 patients with chronic low back pain, and 50 healthy controls. Cold-induced vasospasm was detected in 38% of the patients with fibromyalgia. In this group it was significantly more frequent than in the patients with chronic low back pain (20%, p < 0.05) and healthy subjects (8%, p < 0.001). In the fibromyalgia group, the magnitude of vasospasm as measured by the capillary blood flow deceleration after cold application correlated negatively with the pain intensity as measured by pain score (r = -0.3839, p < 0.01). No differences in clinical appearance were found between patients with and without cold-induced vasospasm in both the fibromyalgia and low back pain group. 相似文献
77.
RS Hogg AE Weber KJ Craib AH Anis MV O'Shaughnessy MT Schechter JS Montaner 《Canadian Metallurgical Quarterly》1998,12(16):2203-2209
OBJECTIVE: To estimate the potential direct cost of making triple combination antiretroviral therapy widely available to HIV-positive adults and children living in countries throughout the world. METHODS: For each country, antiretroviral costs were obtained by multiplying the annual cost of triple antiretroviral therapy by the estimated number of HIV-positive persons accessing therapy. Per capita antiretroviral costs were computed by dividing the antiretroviral costs by the country's total population. The potential economic burden was calculated by dividing per capita antiretroviral costs by the gross national product (GNP) per capita. All values are expressed in 1997 US dollars. RESULTS: The potential cost of making triple combination antiretroviral therapy available to HIV-positive individuals throughout the world was estimated to be over US$ 65.8 billion. By far the greatest financial burden was on sub-Saharan Africa. The highest per capita drug cost in this region would be incurred in the subregions of Southern Africa (US$ 149) followed by East Africa (US$ 116), Middle Africa (US$ 44), and West Africa (US$ 42). In the Americas, subregional data indicated the highest per capita drug cost would be in the Latin Caribbean (US$ 22), followed by the Caribbean (US$ 17), Andean Area (US$ 7), the Southern Cone (US$ 6), North America (US$ 6), and Central American Isthmus (US$ 5). In Asia and Europe the percentage of the GNP necessary to finance drug therapy was less than 1% in most countries examined. CONCLUSION: Our results demonstrate that the cost of making combination antiretroviral therapy available worldwide would be exceedingly high, especially in countries with limited financial resources. 相似文献
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79.
J Deckert AM Torres SM Hwang AJ Kastaniotis RS Zitomer 《Canadian Metallurgical Quarterly》1998,150(4):1429-1441
Aerobic repression of the hypoxic genes of Saccharomyces cerevisiae is mediated by the DNA-binding protein Rox1 and the Tup1/Ssn6 general repression complex. To determine the DNA sequence requirements for repression, we carried out a mutational analysis of the consensus Rox1-binding site and an analysis of the arrangement of the Rox1 sites into operators in the hypoxic ANB1 gene. We found that single base pair substitutions in the consensus sequence resulted in lower affinities for Rox1, and the decreased affinity of Rox1 for mutant sites correlated with the ability of these sites to repress expression of the hypoxic ANB1 gene. In addition, there was a general but not complete correlation between the strength of repression of a given hypoxic gene and the compliance of the Rox1 sites in that gene to the consensus sequence. An analysis of the ANB1 operators revealed that the two Rox1 sites within an operator acted synergistically in vivo, but that Rox1 did not bind cooperatively in vitro, suggesting the presence of a higher order repression complex in the cell. In addition, the spacing or helical phasing of the Rox1 sites was not important in repression. The differential repression by the two operators of the ANB1 gene was found to be due partly to the location of the operators and partly to the sequences between the two Rox1-binding sites in each. Finally, while Rox1 repression requires the Tup1/Ssn6 general repression complex and this complex has been proposed to require the aminoterminal regions of histones H3 and H4 for full repression of a number of genes, we found that these regions were dispensable for ANB1 repression and the repression of two other hypoxic genes. 相似文献
80.
IuG Suchkov IV Khudiakov EN Emel''ianenko MI Levi VI Pushkareva IIu Suchko VIu Litvin EV Kulesh RS Zotova AL Gintsburg 《Canadian Metallurgical Quarterly》1997,17(4):42-46
The purpose of this study was to find criteria characteristic for patients in need of care and social services. The criteria should serve as a guideline for patients and staff to facilitate care planning before discharge. The sample consisted of 49 patients, born before 1925, in need of emergency inpatient treatment, admitted to medical- or orthopaedic wards. Data of the patient's self care needs were collected by interviews, assessment of self care status and need of treatment. The patients could be divided into three groups depending on type of discharge. Group A (n = 27) discharged home, group B (n = 7) discharged to geriatric clinic and group C (n = 15) discharged and in need of further care and social services. Criteria indicating the patients further assistance from the community were in group C (medical- and orthopaedic wards) deficit in daily living activities and locomotion. Group B had an increased need of support from the physiotherapist and the occupational therapist, in locomotion as well as daily living activities The physician's assessment showed that the criteria behind the decision "no further medical treatment appropriate" and "ready for discharge" were not related to medical impairment but to lack of self care, need of care, rehabilitation and social services. 相似文献