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971.
Ovarian hormone deficiency decreases and estrogen (E2) and growth hormone (GH) administrations increase intestinal absorption of calcium (Ca++). However, the underlying mechanisms are uncertain. To examine whether alterations in the binding characteristics of intestinal estrogen receptors (ERs) are involved, we developed and validated methods for simultaneous measurement of intestinal ERs in cytosolic and nuclear fractions and applied these techniques to four groups of female rats: sham-operated, ovariectomized (Ovx), Ovx + 5 micrograms E2/kg b.wt./day and Ovx + 8 mg GH/kg. b.wt./day. All animals were killed on day 21, and mucosal cells harvested from the duodenum for ER determination. The cytosolic and nuclear ERs were 117.2 +/- 2.7 fmol/mg protein and 64.9 +/- 1.2 fmol/mg DNA, respectively, in sham-operated rats and decreased by 16.1% and 17.0% to 98.4 +/- 1.7 fmol/mg protein and 53.8 +/- 1.3 fmol/mg DNA, respectively in Ovx rats (P < .001). E2 therapy prevented completely the decrease in cytosolic and nuclear ERs that occurred in Ovx rat (126.1 +/- 2.9 fmol/mg protein and 68.0 +/- 3.0 fmol/mg DNA, respectively, in the E2-treated group). Similarly, GH administration prevented the decrease in cytosolic and nuclear ERs that resulted from ovariectomy (119.2 +/- 3.2 fmol/mg protein and 63.4 +/- 1.3 fmol/mg DNA, respectively, in the GH-treated group). The Kd of nuclear ER-ligand complex was 2.0 +/- 0.03 nM in sham-operated rats and was slightly modulated by Ovx, E2 and GH (3.3 +/- 0.02, 2.33 +/- 0.09 and 2.23 +/- 0.04 nM, respectively, P < .001), but the Kd of cytosolic ER-ligand complex was not altered by Ovx, E2 or GH. Our findings indicate that E2 deficiency down-regulates, whereas E2 and GH administrations up-regulate intestinal ERs and prevent ovariectomy-induced decrease in receptor binding affinity. We conclude that E2 deficiency, E2 and GH may modulate intestinal Ca++ absorption, in part, by altering the abundance and binding characteristics of intestinal ERs. 相似文献
972.
IS Anand BA Prasad SS Chugh KR Rao DN Cornfield CE Milla N Singh S Singh W Selvamurthy 《Canadian Metallurgical Quarterly》1998,98(22):2441-2445
BACKGROUND: High-altitude pulmonary edema (HAPE) is characterized by pulmonary hypertension, increased pulmonary capillary permeability, and hypoxemia. Treatment is limited to descent to lower altitude and administration of oxygen. METHODS AND RESULTS: We studied the acute effects of inhaled nitric oxide (NO), 50% oxygen, and a mixture of NO plus 50% oxygen on hemodynamics and gas exchange in 14 patients with HAPE. Each gas mixture was given in random order for 30 minutes followed by 30 minutes washout with room air. All patients had severe HAPE as judged by Lake Louise score (6.4+/-0.7), PaO2 (35+/-3. 1 mm Hg), and alveolar to arterial oxygen tension difference (AaDO2) (26+/-3 mm Hg). NO had a selective effect on the pulmonary vasculature and did not alter systemic hemodynamics. Compared with room air, pulmonary vascular resistance fell 36% with NO (P<0.001), 23% with oxygen (P<0.001 versus air, P<0.05 versus NO alone), and 54% with NO plus 50% oxygen (P<0.001 versus air, P<0.005 versus oxygen and versus NO). NO alone improved PaO2 (+14%) and AaDO2 (-31%). Compared with 50% oxygen alone, NO plus 50% oxygen had a greater effect on AaDO2 (-18%) and PaO2 (+21%). CONCLUSIONS: Inhaled NO may have a therapeutic role in the management of HAPE. The combined use of inhaled NO and oxygen has additive effects on pulmonary hemodynamics and even greater effects on gas exchange. These findings indicate that oxygen and NO may act on separate but interactive mechanisms in the pulmonary vasculature. 相似文献
973.
Lobar atrophy is a rare morphologic change of the liver. We describe a 73-year-old woman with mild liver dysfunction and history of Sj?gren's syndrome who had right hepatic lobar atrophy. Serum biochemistry levels were as follows: albumin, 4.5 g/dl; total bilirubin, 1.0 mg/dl; alanine aminotransferase, 25 international units/l; aspartate aminotransferase, 27 international units/l; alkaline phosphatase, 333 international units/l; and gamma-glutamyl transpeptidase, 332 international units/l. Serological data were as follows: rheumatoid factor, 27.9; anti-nuclear antibody, 1:640; and antismooth muscle antibody, 1:80. Viral markers for hepatitis B were all negative. Anti-hepatitis C virus (anti-c-100) was negative. Portal hypertension developed thereafter, and the patient died of hepatic failure at age 76. Postmortem examination revealed autoimmune hepatitis with moderate fibrosis, portal vein thrombus, and complete obstruction of the right hepatic duct due to hepatolithiasis. Terminal hepatic failure resulted from combination of decreased hepatic volume due to the right lobar atrophy, exacerbation of autoimmune hepatitis in the remnant left hepatic lobe, decreased portal venous blood flow due to thrombosis, portal hypertension, and cholangitis with hepatolithiasis. This is the first reported case of hepatic lobar atrophy due to autoimmune hepatitis. From a clinical standpoint, patients with hepatic lobar atrophy, even if asymptomatic, should be followed up with careful attention to progression of liver diseases, portal hypertension, and biliary complications. 相似文献
974.
Protein malnutrition leads to multiple detrimental alterations of host immune responses to mycobacterial infection. In this study, we demonstrated that splenocytes from low-protein (LP) guinea pigs vaccinated 6 weeks previously with attenuated Mycobacterium tuberculosis H37Ra failed to control the accumulation of virulent M. tuberculosis H37Rv in cocultured autologous peritoneal macrophages, despite the fact that they were able to control the accumulation of virulent tubercle bacilli in cocultured syngeneic peritoneal macrophages from normally nourished guinea pigs as successfully as did those from high-protein (HP) counterparts. Vaccine-induced growth control of virulent M. tuberculosis H37Rv in these cocultures appeared to be mediated by CD4 lymphocytes but not CD8 cells. Tuberculin (purified protein derivative [PPD])-induced lymphoproliferation was markedly impaired in vaccinated LP guinea pigs, and the depletion of CD4 lymphocytes significantly decreased lymphocyte proliferation whereas CD8 cell depletion did not. Protein malnutrition also impaired the abilities of cells from vaccinated LP guinea pigs to produce cytokines, including interferon, tumor necrosis factor alpha (TNF-alpha) and transforming growth factor beta (TGF-beta), in response to PPD, despite the demonstration of higher serum levels of TNF-alpha and TGF-beta after an intravenous injection of PPD into LP guinea pigs. In contrast, peritoneal macrophages from protein-malnourished guinea pigs produced a higher level of TGF-beta 4 days after infection in vitro with M. tuberculosis H37Rv than did those from protein adequate controls. These results suggest that dietary protein malnutrition impairs vaccine-induced resistance to M. tuberculosis, in part, by altering the cytokine profile to favor macrophage deactivation. 相似文献
975.
Lymphoma is a common opportunistic complication of immunosuppression. Lymphomas in patients with the acquired immunodeficiency syndrome (AIDS) may broadly be divided into four major types: intermediate- or high-grade systemic lymphoma, primary central nervous system (CNS) lymphoma, Hodgkin's disease (HD) and primary effusion lymphoma. Multiple active regimens have been identified for patients with AIDS-related systemic lymphoma. However, despite high initial complete response rates, most studies have reported a median survival of less than 1 year for these patients, with approximately half of the patients dying from lymphoma and half from opportunistic infections or other AIDS-related complications. The standard therapeutic approach for patients with AIDS-related primary CNS lymphoma is radiotherapy, although recent studies using combinations of chemotherapy with radiotherapy may offer an improvement in therapy for this group of patients who have very poor overall prognosis. Lymphoproliferative disease in patients after solid organ or bone marrow transplantation represents with a spectrum of disorders. No standard approach for therapy in this group of patients has been clearly established. 相似文献
976.
977.
We hypothesized that psychiatrists with high dual-agency potential (military and health maintenance organization [HMO] psychiatrists) were more likely than non-HMO civilian psychiatrists to engage in dual relationships, report pressures to do so, participate in other general boundary-crossing activities, and report associated counter-therapeutic outcomes (boundary violations). Ninety military and 191 demographically matched civilian psychiatrists reported the number of boundary-crossing activities (including dual relationships) and associated counter-therapeutic outcomes in the preceding year with adult patients. Military and HMO psychiatrists reported greater external pressures than non-HMO civilian psychiatrists to engage in dual relationships; however, all three groups were similar in their reported numbers of dual relationships. The reported boundary-crossing activities and dual relationships studied here are not necessarily associated with reported boundary violations. The relative risk of a particular boundary crossing associating with harm to a patient likely depends on the therapeutic context and should be determined on a case-by-case basis. 相似文献
978.
In the present study, a series of branched and partially crosslinked poly(ethylene terephthalate) (PET) samples were prepared by the two‐stage melt polycondensation method, using different amounts of trimethyl trimellitate (TMT) as polyfunctional monomer. The samples were characterised with respect to intrinsic viscosity, density and gel content as well as thermal and mechanical properties. The intrinsic viscosity of the polymers ranged between 0.7 and 1.6 dl g?1 depending on the concentration of the TMT comonomer. When TMT was used at a concentration 0.625 wt% or higher, gel formation was observed. For the sample containing 1.25 wt% TMT, almost half of the polymer was insoluble in phenol–tetrachloroethane mixture, due to extensive crosslinking. The increase of TMT content resulted in a small decrease of crystallinity attributed to branching and crosslinking, both of which restrict the organisation of the polymer chains in the crystal structure. This was reflected directly in the thermal properties of the polymers prepared. Increasing the TMT content decreased the melting point and the heat of fusion. In contrast, cold crystallization and glass transition temperatures were shifted to higher temperatures. Mechanical properties like tensile strength and elongation at break increased with increasing the content in branching agent. However, crosslinking had a negative effect on elongation at break. Copyright © 2003 Society of Chemical Industry 相似文献
979.
DN Reddy PG Reddy W Xue HC Minocha MJ Daley F Blecha 《Canadian Metallurgical Quarterly》1993,37(1):25-38
Three experiments, using 85 crossbred beef calves, were conducted to evaluate the adjuvanticity of single, multiple, and combined doses of recombinant bovine IL-1 beta (rBoIL-1 beta) and recombinant bovine IL-2 (rBoIL-2), with a modified-live bovine herpesvirus-1/parainfluenza-3 (BHV-1/PI-3) virus vaccine and a killed bovine viral diarrhea (BVD) virus vaccine. Cytokines were administered intramuscularly at vaccination but at different injection sites. All cytokine treatments increased non-major histocompatibility complex (MHC)-restricted cytolytic capability of peripheral blood mononuclear cells (PBMC) against virus-infected target cells and serum neutralizing (SN) antibody titers to BHV-1 and BVD virus. Multiple, consecutive injections of rBoIL-2 generally showed the greatest adjuvant effect, and no additive effect was observed when rBoIL-1 beta and rBoIL-2 were administered together. In a challenge experiment, calves were vaccinated with a modified-live BHV-1/PI-3 vaccine and infected with BHV-1 on Day 21. Cytokine-treated calves had higher SN antibody titers to BHV-1 than did the control calves at the time of challenge. Calves that were administered rBoIL-2 on 5 consecutive days shed less BHV-1 and had the highest SN antibody titer to BHV-1 (Day 28). These data suggest that rBoIL-1 beta and rBoIL-2 may be useful immunoadjuvants for bovine respiratory disease virus vaccines. 相似文献
980.
Eighteen male social drinkers underwent four training sessions during which they ingested two colour-coded drinks (red or blue, balanced for drink type); one containing alcohol (aliquots of 0.1 g/kg) and the other placebo (aliquots of orangeade). Following the training sessions, subjects were presented with both drinks, and instructed to choose the drink they felt like consuming and to indicate their preference for their chosen drink over the other drink. In addition, they were instructed to consume the first drink but that all subsequent drinks (total of six drinks), offered at 10-min intervals, were optional. A number of trait characteristics were assessed including alcohol outcome expectancies, drinking habits and personality traits. The acute effects of alcohol on mood was also evaluated by comparing subjective ratings following alcohol and placebo during the training sessions. Of the 18 subjects, 12 chose alcohol at least once ('samplers'), whereas six never chose alcohol ('non-samplers'). Over the three sessions, however, alcohol and placebo were chosen equally. When alcohol was chosen, subjects drank significantly more than when placebo was chosen, which may be consistent with a priming effect of drinking alcohol. The amount of alcohol drunk was seen to correlate with the alcohol expectancy factor 'sociability'. Subjective reports of feeling 'alert', 'clear-headed', 'quick-witted', and 'attentive' all showed a main effect of choosing behaviour (i.e. 'samplers'/'non-samplers'). Further analysis indicated that this effect was due to 'samplers' reporting increased subjective ratings of these mood states following the ingestion of alcohol compared to 'non-samplers'. These increased subjective ratings were also positively correlated with the amount of alcohol consumed by the subjects during the choice procedure. No other relationships were found between the amount of alcohol consumed and any of the other state or trait measures. These data suggest that social drinkers who sample alcohol in a laboratory setting can be primed by alcohol to consume more. The results also indicated that the amount drunk was related to the degree to which subjects expected alcohol to increase sociability and to reports of subjective stimulant effects of alcohol (e.g., 'alert', 'clear-headed', 'quick-witted', and 'attentive'). 相似文献