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31.
The area under the liver was dissected in 27 human autopsy specimens to search for lymph nodes in the fissures. Nodes were present in all instances. They were in the transverse fissure, posterior to the portal vein, posterior to pars transversus of the left portal vein and associated with the left hepatic artery. The size varied from 2 millimeters to 2 centimeters. Each node was histologically confirmed. Nodes were infrequent and small on the right. Nodes were not found between the portal vein, hepatic artery and bile ducts in the fissures. Nodes were found outside the fissures in the fascia between the bile duct and hepatic artery. Occlusion of the portal vein and hepatic artery could be expected before occlusion of the bile duct. Node enlargement in the transverse fissure is anticipated as a rare cause of jaundice. 相似文献
32.
33.
The validation of otological care in the previous quarter century has been based, by and large, on short-term follow-up information. The rapid variation in procedures introduced during this period indicates that there may be need for further consideration. Analyses based on relatively short duration have led the "acceptance" of a variety of diagnostic and treatment methods which have proven disappointing in some cases. To help avoid this invalid "acceptance," a review of patients with significant follow-up may result in a more critical evaluation of future procedural changes. This presentation will be in four parts: 1. History of the office structure. 2. Discussion of five long-term patients that illustrates and supports certain otological concepts. 3. A review of surgical care for chronic suppurative otitis media in 1968. 4. A review of patients treated for serous otitis media with myringotomy and tubal insertion in 1968. 相似文献
34.
1. The biosynthesis of cholesterol was studied, by using various precursors, in rats subjected to several dietary regimes. 2. The use of 3H2O as a substrate to demonstrate differences in cholesterogenesis under various conditions was validated by using rats fed on cholesterol or cholestyramine. Cholesterol feeding resulted in decreased cholesterogenesis, whereas cholestyramine caused an increase. 3. With acetate as precursor, the biosynthesis of both digitonin-precipitable sterol and fatty acids was increased in vitro in response to a meal. 4. In rats fed ad libitum, hepatic cholesterogenesis was increased at midnight relative to mid-morning as measured by using acetate precursor in vitro. However, no such difference was found by using 3H2O in vivo. 5. The lipogenic response was measured in meal-fed rats by using 3H2O or octanoate in vivo. In contrast with findings with acetate in vitro, no postprandial stimulation of cholesterogenesis was seen with either 3H2O or octanoate as precursor, whereas fatty acid biosynthesis from either substrate was increased. 6. These findings are discussed with respect to current theories about the circadian rhythm of cholesterogenesis. Such theories are based on experiments using isolated enzyme measurements or non-physiological precursors such as acetate. 7. It is considered that results obtained with 3H2O give an accurate representation of cholesterogenesis under various conditions, and it is therefore suggested that hepatic cholesterogenesis in rats is not subjected to the same degree of diurnal rhythm as has previously been believed. 相似文献
35.
There are suggestions in the literature that vinyl chloride (VC) acts as a lung irritant. Respiratory questionnaires and lung function tests were administered to 174 chemical (VC) workers, 81 polyvinyl chloride (PVC) workers, 72 former VC workers, and 136 rubber workers, and 68 maintenance workers with exposure to VC, PVC, and rubber. Except for small airways obstruction associated with rubber, increased respiratory symptoms and decreased pulmonary function were not associated with working in chemicals, plastics, or rubber. Some increases in baseline pulmonary function were associated with VC exposure. Acute reductions in pulmonary function were observed in smokers working in chemicals, plastics, and rubber. Heavier cigarette smokers over 40 years of age had the most adversely affected respiratory system. Work was not associated with chronic respiratory effects, but all exposure groups experienced some acute respiratory insult. 相似文献
36.
RJ Howard 《Canadian Metallurgical Quarterly》1976,72(3):317-323
Two patients, ages 7 and 17, with unresectable obstructions within the left ventricular cavity, have been managed by interposing a conduit bearing a porcine aortic valve between the apex of the left ventricle and the infra-renal abdominal aorta. The younger child had idiopathic hypertrophic subaortic stenosis (IHSS) recognized in infancy. At the age of three, a right ventricular myomectomy and a trans-aortic left ventricular myotomy were performed. Symptoms were progressive with congestive failure, diaphoresis, syncope , and angina pectoris. Following construction of a second left ventricular outflow tract with relief of intraventricular obstruction, the patient has become asymptomatic. The second patient has fibrous tunnel obstruction of the left ventricular outflow tracting providing a 100 mm Hg gradient. Fibrous tissue was resected in part through the transaortic route, and a second outflow tract was constructed. A postoperative cardiac catheterization revealed an obliteration of the previous intraventricular gradients and an equal distribution of left ventricular output through the two available outflow tracts. She remains asymptomatic. 相似文献
37.
Partial purification of rabbit aorta contracting substance-releasing factor and inhibition of its activity by anti-inflammatory steroids 总被引:1,自引:0,他引:1
Rabbit aorta contracting substance-releasing factor (RCS-RF) is found in perfusates from guinea pig lungs during anaphylaxis. It has been identified as a small peptide which releases arachidonic acid from lung tissue, thus generating prostaglandin endoperoxides and tbromboxanes and causing bronchocconstriction. Anti-inflammatory steroids block the release of arachidonate by RCS-RF. In this activity their relative potency is very similar to their relative anti-inflammatory potency, suggesting that the two actions may be related. 相似文献
38.
The simple sequential scheme for the extraction and classification of dyes from 1–2–cm lengths of polyacrylonitrile fibres reported by Beattie et al., J. S. D. C, 95 (1979) 295, is revised to avoid misclassification of some basic dyes. 相似文献
39.
Granular S, finely-ground S, iron sulphate and aluminium sulphate were added at two rates to the surface (0–6 cm) of a soil and acidification and leaching of nutrients were measured over 12 months in a laboratory study. Iron and aluminium sulphate both rapidly lowered soil pH in the top 0–6 cm of the soil. There was little difference in soil pH after 3 and 12 months reaction of these two amendments. In contrast, for granular S and finely-ground S there were clear decreases in soil pH between 3 and 12 months reaction with the soil. Finely-ground S was oxidized in the soil faster than granular S and therefore had a more acidifying effect. The top 0–6 cm of the soil was acidified by all the agents used but the deeper soil was less affected. The only treatments which lowered the pH of the 12–18 cm layer below pH 6 were the high rates of iron and aluminium sulphate. Soil acidification resulted in a decrease in exchangeable Ca, Mg and K, an increase in exchangeable Al and a decrease in effective CEC in the acidified soil layers.At both levels of addition, total ionic strength of percolates from the soil followed the order: aluminium sulphate = iron sulphate > finely gound S > granular S > control and was higher at the higher rate of addition. The pH values of percolates followed the order: control > granular S > finely ground S > iron sulphate = aluminium sulphate and were lower at the higher rate of addition. For the amended soils there was a very close relationship between the pattern and total amounts of SO
4
2-
and Ca2+ leached.It was concluded that granular S is not an effective acidifying agent since it is oxidized very slowly in the soil and that acidfying agents should be incorporated to the depth that acidification is required. 相似文献
40.
RJ Biggar ME Taylor JV Neel B Hjelle PH Levine FL Black GM Shaw PM Sharp BH Hahn 《Canadian Metallurgical Quarterly》1996,216(1):165-173
The human T-lymphotropic virus type II (HTLV-II) is found in many New World Indian groups in North and South America and may have entered the New World from Asia with the earliest migration of ancestral Amerindians over 15,000 years ago. To characterize the phylogenetic relationships of HTLV-II strains infecting geographically diverse Indian populations, we used polymerase chain reaction to amplify HTLV-II sequences from lymphocytes of seropositive Amerindians from Brazil (Kraho, Kayapo, and Kaxuyana), Panama (Guaymi), and the United States (the Navajo and Pueblo tribes of the southwestern states and the Seminoles of Florida). Sequence analysis of a 780-base pair fragment (located between the env gene and the second exons of tax/rex) revealed that Amerindian viruses clustered in the same two genetic subtypes (IIa and IIb) previously identified for viruses from intravenous drug users. Most infected North and Central American Indians had subtype IIb, while HTLV-II infected members of three remote Amazonian tribes clustered as a distinct group within subtype IIa. These findings suggest that the ancestral Amerindians migrating to the New World brought at least two genetic subtypes, IIa and IIb. Because HTLV-II strains from Amazonian Indians form a distinct group within subtype HTLV-IIa, these Brazilian tribes are unlikely to be the source of IIa viruses in North American drug users. Finally, the near identity of viral sequences from geographically diverse populations indicate that HTLV-II is a very ancient virus of man. 相似文献