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91.
This 2 × 2 factorial design experiment was conducted to compare the performance of spring-calving Holstein dairy cows (HOL, n = 34) with Swedish Red × Jersey/Holstein crossbred (SR × J/HOL, n = 34) dairy cows within low and medium concentrate input grassland-based dairy systems. The experiment commenced when cows calved and encompassed 1 full lactation. Cows were offered diets containing grass silage and concentrates [70:30 dry matter (DM) ratio, and 40:60 DM ratio, for low and medium, respectively] until turnout, grazed grass plus either 1.0 or 4.0 kg of concentrate/d during the grazing period (low and medium, respectively), and grass silage and concentrates (85:15 DM ratio, and 70:30 DM ratio, for low and medium, respectively) from rehousing and until drying off. No significant genotype × system interactions were present for any of the feed intake or full-lactation milk production data examined. Full-lactation concentrate DM intakes were 769 and 1,902 kg/cow for the low and medium systems, respectively, whereas HOL cows had a higher total DM intake than SR × J/HOL cows in early lactation, but not in late lactation. Although HOL cows had a higher lactation milk yield than SR × J/HOL cows, the latter produced milk with a higher fat and protein content, and thus fat plus protein yield was unaffected by genotype. Milk produced by the SR × J/HOL cows had a higher degree of saturation of fatty acids than milk produced by the HOL cows, and the somatic cell score of milk produced by the former was also higher. Throughout the lactation, HOL cows were on average 30 kg heavier than SR × J/HOL cows, whereas the SR × J/HOL cows had a higher body condition score than the HOL cows. Holstein cows had a higher incidence of mastitis and ovarian dysfunction that SR × J/HOL cows.  相似文献   
92.
A study was made of the energy used in production of standard, white, sliced bread in three UK bakeries. The production chain studied covered all stages from receipt of flour at the bakery to arrival of bread at the retail outlet: primary energy use from all sources averaged 6.99 MJ kg-1 bread. In the complete production system for standard bread, including wheat growing, flour milling, baking and retailing, primary energy consumption was 14.8 MJ kg-1 bread and the energy subsidy (primary energy input: food energy output) for the system was 1.49. Primary energy used in home baking was dependent on the degree of loading of the oven and varied from 4.24–16.05 MJ kg-1 bread baked in a gas oven and from 10.84–54.76 MJ kg-1 bread baked in an electric oven. In comparison with mashed potato, roast beef and reheated canned corn, standard bread showed the lowest energy subsidy by a factor of at least five. The energy subsidy for standard bread production was only one-seventh of the figure which applies to the food system as a whole. The findings suggest that bread is the most energy efficient staple food product of an industrialised food production system.  相似文献   
93.
A method for affinity chromatography of plasma and platelet factor XIII has been developed, based on known structural characteristics of these molecules. Plasma factor XIII is composed of a and b subunits which are held together by noncovalent interactions; platelet factor XIII has only a subunits. a subunit contains free sulfhydryl groups, while in b subunit all the cystines form disulfide bonds. The affinity gel is an organomercurial agarose with p-chloromercuribenzoate as the reactive group. Both the zymogen and activated forms of a subunit reversibly bind to the ligand by forming covalent mercaptide bonds and are eluted by reducing agents. b subunit does not bind to the affinity gel and is held to it only through interaction with a subunit. Affinity chromatography can be used to purify plasma and platelet factor XIII and to study interactions of the subunits. Experiments on the affinity chromatography of purified plasma factor XIII in several stages of activation agree with earlier observations that activation is a two-step procedure in which b subunit is not quantitatively released from the complex until the final stage of activation by Ca2+.  相似文献   
94.
Lactate dehydrogenase (LDH), malate dehydrogenase, and alpha-esterase were studied electrophoretically in a total of 99 semen samples obtained from normal, vasectomized, oligospermic, and infertile males. The enzymatic patterns were compared with total sperm count and percentage sperm motility. Lactate dehydrogenase X was absent in semen samples from oligospermic as well as vasectomized males. An extra LDH band (between the second and third LDH bands) was detectable in samples which had a low sperm count but higher motility (80 to 90%). This extra band was absent in samples with higher sperm count regardless of the level of percentage motility, suggesting that the extra band possibly may be related to motility factors of low sperm count but not normal sperm count. The fastest moving alpha-esterase bands were absent in samples from oligospermic or vasectomized males. These bands were also absent in samples from infertile patients having a very low sperm count. It is not clear whether the fast-moving esterase bands are related to sperm count or possible differences in hormonal levels of individuals with low or zero sperm count samples. The patterns of malate dehydrogenase did not differ in individuals with zero, low, or normal sperm count.  相似文献   
95.
To determine whether chromosome analysis could facilitate the diagnosis of malignant pleural effusions, we examined chromosomes in effusions from 104 unselected patients. An effusion was regarded as malignant if at least three of 30 metaphase cells were hyperdiploid or contained a marker chromosome. Results were compared with standard cytologic diagnoses. All 22 benign effusions were diagnosed correctly by cytologic examination, but one nosed correctly by cytologic examination, but one (acute rheumatoid lung disease) was misclassified as positive by chromosome criteria. Of the 82 malignant effusions, 53 (65 per cent) were diagnosed correctly by cytologic tests, as compared with 58 (71 per cent) by chromosome analysis (P greater than 0.2). Among patients with malignant neoplasms, 13 had leukemia or lymphoma; only four of these (31 per cent) were diagnosed by cytologic tests as compared with 11 (85 per cent) by chromosome analysis (P less than 0.01). The combination of standard cytologic and chromosome analyses correctly identified 83 per cent of the neoplasms, a result significantly better than that with either technic alone (P less than 0.01).  相似文献   
96.
A family is described in which the mother and 2 of the 5 children had Felty's syndrome, a pattern of inheritance suggesting a dominant defect and one which has not previously been reported. The family is also of interest in that the other sib had rheumatoid arthritis.  相似文献   
97.
Several methods of damaging red blood cells (RBCs) for splenic imaging were compared to determine the optimum approach. The RBCs from donor animals were labeled with 99mTcO4- and damaged by heat, excess acid citrate dextrose (ACD), excess Sn(II) ion, or the sulfhydryl inhibitors N-ethylmaleimide (NEM) or p-hydroxymercuribenzoate (PMB). The organ distributions of undamaged and damaged RBCs were determined in rats, and splenic imaging studies were performed in rabbits. Splenic deposition and spleen-to-liver ratios with heat- or sulfhydryl-damaged 99mTc-RBCs were significantly greater (p less than 0.001) than the values obtained using ACD or Sn(II) ion. Heat-damaging produces good splenic localization of 99mTc-RBCs but requires rigidly controlled incubation conditions. NEM-damaging provides an excellent and predictable alternative approach.  相似文献   
98.
A prospective study was performed to determine the incidence of group B streptococci cultured from the cervix in a series of obstetric clinic patients at St. Margaret's Hospital. Cultures were taken during each trimester and planted to both a blood agar plate and a selective broth medium. Of a total of 812 cultures, 18 were positive, an over-all incidence of 2.2 per cent. During the first, second, and third trimesters, 2.2 per cent, 2.5 per cent, and 1.9 per cent of cultures were positive, respectively. Women with positive cultures were treated with a 10 day course of oral penicillin or a suitable alternative; four of 16 had persistent positive cultures at the end of the first treatment period, three of these four responded to a second course of antibiotics, and the remaining patient responded after a third treatment course. The total number of positive cultures by selective broth was 24, compared to nine in blood agar, indicating a 2.7-fold increase in pickup by the selective broth.  相似文献   
99.
Randomly assigned 15 volunteer and 15 nonvolunteer undergraduates to 1 of 2 conditions. In the choice condition, Ss were led to believe that they had a choice between 2 hypothetical relaxation treatments that both they and another S would receive. Ss in the 2nd condition were denied the choice of treatment, receiving the treatment chosen by another S. All Ss, regardless of choice, actually received the same taped relaxation treatment. As predicted, volunteers who were given a choice between treatments significantly valued the treatment more and reported the treatment to be significantly more effective than volunteers who had no choice. Nonvolunteers, viewing choice as less important than volunteers, were not significantly affected by the subsequent responsibility manipulation. Whereas volunteering may be a reliable source of bias, the degree to which the volunteer feels responsible for the success of the outcome appears to predict the direction of the bias. Findings are relevant to both the clinician and to clinical outcome research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
Investigated the influence of confederates' verbal evaluations of psychological test data on clinical psychology graduate students' evaluations. 30 clinical psychology graduate students rated 8 artificially constructed Rorschach protocols by means of a Q sort and a diagnosis checklist. One half of the Ss verbally rated the protocols after 3 confederates who posed as graduate students had purportedly rated them; the other half rated the protocols after 2 confederates who posed as graduate students and one as a PhD clinical psychologist had purportedly rated them. The confederates' evaluations varied from being not discrepant to highly discrepant with the actual diagnoses of the protocols. Ss' evaluations on both dependent measures were influenced by the confederates' prior evaluations, especially when the confederate was designated as having higher status. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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