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101.
基于近红外发射光谱的背反射光随时间的ΔBS 得到的SI 为评价指标,采用Box-Behnken 设计研究了果胶用量、均质压力、均质温度对褐色乳饮料稳定性的影响,回归分析得到优化参数为:果胶用量2.8g/L,均质压力21MPa,均质温度42℃。  相似文献   
102.
在反辐射导弹(ARM)对抗有源诱偏问题中,ARM导引头所面临的信号环境非常复杂,很难用某种单一的算法来实现抗诱偏。针对此问题,提出一种分段处理的反辐射被动导引策略。基于对 ARM抗诱偏过程中信号变化特点的分析,整个导引过程分为3个导引段,给出了各段中导引头的任务以及采用的信号处理算法。该策略的主要思想是将一个复杂问题分解为3个相对简单的子问题,具有一定的科学性和可操作性,仿真实验验证了所提策略的有效性和可行性。  相似文献   
103.
Arterial blood pressures were taken by the Doppler ultrasound method in 134 unselected mature neonates (birthweights 2,600-3,900 grams) who were managed in the same manner after birth. Blood pressures were measured at 3-5, 10 and 30 minutes of life and, if indicated, intermittently during the next 24-48 h. Left and right arm pressures were identical or differed by only 1-2 mm Hg. Lower than normal blood pressures were found in 4 groups of infants: those born by cesarean section, those recovering from intrauterine asphyxia, those exposed to maternal anti-hypertensive therapy, and those whose mothers received thiopental within four minutes of delivery. Return of the low pressures to within the normal range was fastest following thiopental induction in the absence of fetal asphyxia and slowest after antihypertensive therapy.  相似文献   
104.
Serine proteases inhibitor with pl-7.3, isolated from potatoe tubers by isoelectric focusing procedure as described previously (V.V. Mosolov et al., Bioorganic Chem., 1, 1449, 1975), was homogeneous under ultracentrifugation, having sedimentation coefficient S20,w 2.8S. Its molecular weight, investigated by sedimentation equilibrium and gel filtration through Sephadex G-100, was found to be 32500 and 31500 respectively. The Stokes radius R and frictional ratio f/fo were found to be 24 A and 1.14. The molecular weight of the inhibitor as determined by sodium dodecylsulfate polyacrylamide electrophoresis was twice as low as determined in ultracentrifuge and by gel filtration procedure. It is suggested that the inhibitor is dimer and consists of two protomers of equal molecular weight.  相似文献   
105.
Changes in sugars and polyols content of fruits and leaves of three cultivar of peach, from fruit set to over maturity, have been studied. Sucrose, glucose, fructose and sorbitol were found both in leaves and in fruits. In fruits, inositol and galactose were also found but only in traces. Redhaven fruits show the greatest total sugars content (sorbitol included) (866 mg/g.d.m.)followed in order by Favorita and Prodigiosa ones (771 and 694 mg/g.d.m.) For Redhaven and Favorita fruits, at harvest matuity, the sugar present in greatest amount was sucrose followed in order by glucose, fructose and sorbitol. On the contrary, in Prodigiosa fruits the order was sucrose, sorbitol, fructose and glucose. In the leaves of three cultivar, the compound present in the greatest amount was sorbitol followed by sucrose, glucose and fructose. The sucrose decrease in leaves during fruit growth could confirm that the disaccharide is the main sugar transported from the leaves to the fruits.  相似文献   
106.
On the basis of own observations of courses the author adopts a definite attitude to the early symptomatology of the rheumatoid arthritis. During the first weeks of the rheumatoid arthritis the following symptoms are found: articular syndromes, more frequently in form of obstinate polyarthralgias, mono-oligoarthritis, accompanied by morning rigidity and accelerated BSR as well as impairment of the general condition. In the majority of the patients only the tentative diagnosis rheumatoid arthritis may be made. After a one to three months' course of the disease the diagnosis becomes more probable. It is above all based on constancy and symmetry, characteristic localisation of the articular process, morning rigidity, radiologically paraarticular loosening of the structure and morphological symptoms of an acute and subacute synovialitis. 6 to 12 months after the beginning of the disease a clinical picture forms which allows to make the diagnosis of a certain or classical rheumatoid arthritis in accordance with the criteria of the ARA. The occurrence of a high activity of multiple affection of the joints (permanent symmetrical polyarthritis including the small joints of the hands and feet), distinctive morning rigidity, high fever and much accelerated BSR, beginning with the first weeks of the disease, speaks for the possibility of the development of an arthrovisceral form of the course of rheumatoid arthritis.  相似文献   
107.
108.
The authors describe relative changes in the blood filling of 46 vascular areas of the body in rats after a moderate and severe blood loss. Moderate blood loss caused redistribution of the blood from the skin of the chest and from the skin of the posterior limbs, the majority of the abdominal and pelvis minor organs, muscular and bone tissues of the abdomen, pelvis minor and extremities into the brain, heart, lungs, kidneys, stomach and into the muscles of the head and neck. In severe blood loss the changes were analogous, but the blood content in the kidneys and the stomach decreased, and there was also a relative elevation of the blood in the muscles and bones of the chest. The intensity of the redistributive reaction in severe blood loss was less than in moderate blood loss.  相似文献   
109.
Studies were carried out to investigate the role of 1,25(OH)2D3 in the skeletal resistance to the calcemic action of parathyroid hormone. The change in serum calcium after the intravenous infusion of 2 U of parathyroid extract (PTE)/kg body wt/hr for eight hours was evaluated in thyroparathyroidectomized (T-PTX) dogs before, and one, two and three days after, induction of uremia by bilateral ureteral ligation (11 dogs) or by bilateral nephrectomy (8 dogs). In another six nephrectomized and T-PTX dogs, 0.68 ug of 1, 25 (OH)2D3/day was given on the day of nephrectomy and for two days thereafter. Serum creatinine in each day of the study was not different among the three groups. The study also included the evaluation of the effect of sham operation (five dogs) and the administration of 1,25 (OH)2D3 to dogs with normal renal function (four dogs) on the calcemic response to PTE, as well as the reproducibility of such a response in the same animal. The results showed that 1) the calcemic response to PTE was markedly impaired after one day of bilateral ureteral ligation or nephrectomy, but the impairment was more severe after nephrectomy; 2) the calcemic response to PTE after two or three days of bilateral ureteral ligation was similar to that seen at one day after nephrectomy; 3) 1, 25 (OH)2D3 partially restored the calcemic response to PTE in the nephrectomized animals to levels similar to those seen after one day of bilateral ureteral ligation; 4) sham operation did not affect the response to PTE, and repeated infusion of PTE produced similar changes in the concentrations of serum calcium. The data indicate that (a) a deficiency of 1,25 (OH)2D3 is at least partly responsible for the skeletal resistance to the calcemic action of PTH in uremia; (b) uremia, per se, may also contribute to this phenomenon; and (c) the kidney after one day of complete bilateral ureteral ligation may still produce 1,25 (OH)2D3, but this ability is compromised after two days of ureteral obstruction.  相似文献   
110.
Circulating plasma progesterone (P) has been quantitatively controlled in the rat "model" through highly specific binding by treatment with anti-P (A-P). Knowing the constant, which characterizes the binding of P to A-P in plasma, sequential assays of circulating A-P and A-P bound total P (Pt) revealed the levels of the biologically active unbound P (Pu). The studies showed that at different stages of gestation the mechanisms through which A-P reduces Pu and terminates pregnancy are the same. However, the doses of AP which effectively reduce Pu and also the critical levels of Pu at which pregnancy terminates are different. The moderate and transient physiologic P-withdrawal (Pw) at midterm permits the continuation of normal gestation, but pregnancy is terminated by a drastic and sustained reduction in Pu. In contrast, when Pu is only slightly and briefly reduced below physiologic levels, pregnancy continues and only retarded conceptus growth signals that Pw occurred. Apparently Pw has to be controlled and measured with "razor's-edge" precision to fully expose and define the regulatory significance of this steroid in the maintenance and termination of pregnancy. Short of this precision, the key regulator of the pregnant uterus will remain buried, as it has been during 40 years, in controversial findings.  相似文献   
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