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911.
We have investigated the effects of some interleukins, such as interleukin (IL) 4, IL7, stem cell factor (SCF) and insulin-like growth factor (IGF-1), known to be involved in human lymphopoiesis, on proliferation, clonal growth and differentiation of cells from two acute lymphoblastic leukemia (ALL) derived pre-B cell lines, that is, Nalm 1, Nalm 6 and purified blasts from 37 childhood ALL. IL4 did not display any promoting activity, an inhibitory effect being observed in two patients. IL7 showed an heterogeneous responsiveness, not related to immunophenotype or cytogenetic features, proliferation and clonal growth being observed in a minority of ALL. In other patients no or even inhibitory effects on proliferation were observed. In one case this inhibition of DNA synthesis was accompanied by maturation of the cells, as demonstrated by the induced expression of surface immunoglobulins (slg); other IL7 treated samples failed to express slg, but showed a decreased expression of terminal deoxynucleotidyl transferase and cALL antigen, suggesting that the cells have a potential of limited maturation by IL7. SCF, known to synergize with IL7 in the most primitive stages of normal B cell development, did not enhance the IL7 response in B cell precursor ALL. Finally IGF-1 failed to induce a proliferative response and clonal growth in BCP ALL either alone or in combination with IL7.  相似文献   
912.
Although there is a recent increase in the use of the isolated pancreatic islets of the rat in the transplantation and functional studies, there has been no detailed quantitative assessment on the size and cellular constituents of islets after the isolation procedure. The present work was undertaken to study the size classes of the isolated islets and the morphometry of their cellular populations. Islets of the rat pancreas were isolated by using the intraductal collagenase digestion technique, the most commonly used procedure for the isolation of pancreatic islets. Different endocrine cells of the isolated islets were stained by immunoperoxidase staining techniques. The distribution of the cellular constituents of the isolated islets was similar to that of the intact islets of the normal pancreas; A, D, and PP cells were peripherally arranged around the centrally located B cells. However, morphometric quantitative study showed that the percent volume and percent number of A, D, and PP cells of the isolated islets were lower than those of the corresponding intact ones. Further, the mean true diameter of the isolated islets was lower than that of the intact ones. These data indicate loss of islet cells during the process of isolation. Most of the lost cells were from the periphery of islets. This may provide an explanation for the incomplete metabolic control and recurrence of hyperglycemia encountered after isolated islet transplantation in the treatment of diabetes mellitus. It seems that further refinements of the isolation techniques are necessary to obtain islet tissue with total cellular integrity, before a complete success in transplantation could be achieved.  相似文献   
913.
Soluble mitochondrial F1 and F1 in complex with the natural ATPase inhibitor protein (F1-IP) catalyze the spontaneous synthesis of [gamma-32P]ATP from medium [32P]phosphate and enzyme-bound ADP when incubated in media with dimethylsulfoxide (Me2SO); under these conditions, the synthesized [gamma-32P]ATP is not released into the media, it remains tightly bound to the enzymes [Gómez-Puyou, A., Tuena de Gómez-Puyou, M. & de Meis, L. (1986) Eur. J. Biochem. 159, 133-140]. Some of the characteristics of the synthesized [gamma-32P]ATP were studied in F1 and F1-IP (ATPase activities of 70 and 1-3 micromol x min(-1) x mg(-1), respectively). In Me2SO media, gamma-phosphate of synthesized ATP in F1 or F1-IP exchanges with medium phosphate. From the rates of the exchange reaction, the half-times for hydrolysis of the synthesized ATP in F1 and F1-IP were calculated: 45 min and 58 min for F1 and F1-IP, respectively. The course that synthesized [gamma-32P]ATP follows after dilution of the Me2SO synthetic mixture with aqueous buffer was determined. After dilution, the half-life of synthesized ATP in F1 was less than 1 min. In F1-IP, ATP was also hydrolyzed, but at significantly lower rates. In F1-IP, dilution also produced release of the synthesized [gamma-32P]ATP. This was assayed by the accessibility of [gamma-32P]ATP to hexokinase. About 25% of [gamma-32P]ATP synthesized in F1-IP, but not in F1, was released into the media after dilution with aqueous buffer that contained 20 mM phosphate. Release of tightly bound ATP required the binding energy of phosphate and solvation of F1-IP, however, the particular kinetics of F1-IP were also central for medium ATP synthesis in the absence of electrochemical H+ gradients.  相似文献   
914.
BACKGROUND: The aim of this retrospective study is to analyze the short and long term results of two different surgical treatments in patients with subclavian lesions: common carotid-subclavian artery bypass (CSB) versus transposition of subclavian artery on the common carotid artery (SCT). METHODS: From 1981 until 1995, 40 non randomized patients with symptomatic subclavian steal underwent 20 CSBs and 20 SCTs. Risk factor rates were equally balanced in the two groups. Surgery was carried out routinely under general anesthesia, with electroencephalic continuous monitoring. Patency of revascularization was assessed by physical examination, brachial blood pressure determinations, ultrasound sonography and angiography whenever recurrence of symptoms developed or when the function of repair was in doubt. Patients were examined every year. In Spring 1996 (range 9-189 mos, average 7 years) a general clinical-instrumental follow-up was performed. RESULTS: In the short term (<30 days) mortality was 5%: one death (5%) for pulmonary embolism in a patient with CSB and one for myocardial infarction in a patient with SCT. The early thrombosis rate was 5% (1 CSB and 1 common carotid artery distal to a patent SCT). During follow-up 10 patients (25%) died and 6 were lost. The six-year actuarial patency rate was 100% for SCT and 66% for CSB. Moreover there were 3 thromboses of the vertebral artery homolateral to patent CSBs. CONCLUSIONS: In conclusions SCT should be considered the surgical technical choice for the treatment of proximal subclavian artery lesions.  相似文献   
915.
Cardiodilatin (CDD)/atrial natriuretic peptide (ANP) is a 28-amino acid peptide hormone known to be synthesized in the heart of a large number of different vertebrates. It plays an important role in the regulation of blood pressure and natriuresis/diuresis. Since the cardiovascular system of the horse has to meet the highest requirements concerning its physiological performance, we intended to characterize the cardiodilatin/atrial natriuretic peptide system of this species. By means of immunohistochemistry and immunoelectron microscopy, we precisely identified auricular cardiocytes as the loci of CDD/ANP synthesis. Using aortic smooth muscle relaxation assay and CDD/ANP-ELISA, we succeeded in isolating the biologically active prohormone. We subsequently cloned the equine cDNA of the CDD/ANP precursor protein and deduced its primary sequence. The entire precursor protein is in good agreement with the CDD/ANP prohormones of other mammals. The deduced theoretical average Mr of equine CDD/ANP-1-126 is 13,764, corresponding to the molecular weight of purified peptide determined by ESI-MS. Our findings suggest that equine CDD/ANP is produced in auricular cardiocytes and the predominant storage form of CDD/ANP in the auricle is the prohormone CDD/ANP-1-126.  相似文献   
916.
SKOR, a K+ channel identified in Arabidopsis, displays the typical hydrophobic core of the Shaker channel superfamily, a cyclic nucleotide-binding domain, and an ankyrin domain. Expression in Xenopus oocytes identified SKOR as the first member of the Shaker family in plants to be endowed with outwardly rectifying properties. SKOR expression is localized in root stelar tissues. A knockout mutant shows both lower shoot K+ content and lower xylem sap K+ concentration, indicating that SKOR is involved in K+ release into the xylem sap toward the shoots. SKOR expression is strongly inhibited by the stress phytohormone abscisic acid, supporting the hypothesis that control of K+ translocation toward the shoots is part of the plant response to water stress.  相似文献   
917.
Antidepressant-induced adverse sexual effects are becoming more frequently reported by patients who require pharmacotherapy. A MED-LINE search was conducted to generate articles reporting such events. We report here on the sexual side effects associated with tricyclics, monoamine oxidase inhibitors including moclobemide, selective serotonin reuptake inhibitors, bupropion, and on the newer antidepressants venlafaxine and nefazadone. We conclude that adverse sexual effects are an increasingly important side effect of antidepressant medications, and patients must be routinely asked about their occurrence.  相似文献   
918.
Adhesions have been suggested as a possible cause of chronic abdominal pain, but the reports of their etiological role conflict. Lysis of adhesions has been proposed as the therapeutic modality of choice, although the reports of success are controversial. The aim our prospective study was to determine whether laparoscopic adhesiolysis ameliorates chronic abdominal pain in patients with abdominal adhesions. Forty-one patients with chronic abdominal pain lasting for more than 6 months, but with no abnormal findings other than adhesions found at laparoscopy, underwent laparoscopic adhesiolysis. 37 patients (90.2%) were available for follow-up after a median time interval of 18 months (range: 12-41 months). Twenty-two patients (59.4%) were free from abdominal pain and 9 (24.3%) patients reported significant amelioration of their pain. Six (16.2%) patients had no amelioration. In conclusion the laparoscopy is an effective tool for the evaluation of patients with chronic abdominal pain, and laparoscopic adhesiolysis cures of ameliorates chronic abdominal pain in more than 80% of patients.  相似文献   
919.
Saksenaea vasiformis, a zygomycete belonging to the order Mucorales, is a rare cause of zygomycosis with 17 cases documented world-wide. It usually infects the immunocompromised or traumatized and has a high mortality rate. Because of its failure to sporulate under normal laboratory conditions it may be difficult to identify. We describe here an unusual case report of Saksenaea vasiformis with sporulation and identification within a week using a modified sporulation technique.  相似文献   
920.
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