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141.
We studied the possible participation of endothelin-1 (ET-1) in the pathogenesis of renal damage in glycerol-induced acute renal failure (ARF). Cortical mRNA expression of ET-1 increased, peaking at 10 hr postinjury, but this did not occur in the medulla, plasma concentration and urinary excretion of ET-1 also increased in this model. There was no change in ETA receptor mRNA, whereas the ETB receptor tended to be down-regulated in the kidney after glycerol administration. In situ hybridization study demonstrated that elevated expression of prepro ET-1 was predominantly localized in cells in the proximal tubules of the nephritic kidney. The administration (30-3 mg/kg) of S-0139, (+)-disodium 27-[(E)-3-[2-[(E)-3-carboxylatoacryloylamino]-5-hydroxyphenl ]acrylayl oxy]-3-oxoolean-12-en-28-oate, an ETA selective antagonist, after initiation of insult offered dose-dependent prevention against ARF, demonstrating preventing of renal function impairment and mortality. These findings indicate that ET-1 participates in the pathogenesis of acute tubular injury in glycerol-induced ARF and that ETA antagonist may be useful in the treatment of some types of human ARF.  相似文献   
142.
A crossover clinical trial was carried out to compare the effectiveness and safety of granisetron alone (40 micrograms/kg) with that from a combination of granisetron plus methylprednisolone (MPL, 10 mg/kg) for control of emesis and vomiting induced by anticancer drugs in children with cancer. Complete control of emesis and vomiting were achieved in 95% (19/20 cases) of patients receiving the combination compared to 85% (17/20 cases) of patients receiving granisetron alone. There were no clinical toxicities or side effects in either treatment group. These data indicated that the combination of granisetron plus MPL was superior for control of emesis and vomiting in children receiving cytostatic anticancer drugs.  相似文献   
143.
144.
We describe a surgical technique for replacing the hip joint capsule using synthetic mesh after oncological resections of the proximal femur that resulted in gross intraoperative instability of the prosthetic reconstruction. The results of its use in 13 patients, 6 of whom also had pelvic resections, are described. These patients were selected from a total group of 88 patients undergoing proximal femoral replacement, 75 of whom did not require capsular replacement (none of these 75 patients have experienced dislocation). In the group requiring capsular reconstruction, 1 of 4 patients with bipolar hemiarthroplasty and 4 of 9 patients with total hip replacements experienced dislocation after operation. Of the dislocated total hip replacements, 1 remains chronically dislocated, and 3 were successfully stabilized by open reduction with further capsular augmentation. Given that the resections involved removal of most of the soft tissues stabilizing the hip joint, we believe that the technique of capsular reconstruction is useful in this difficult group of patients.  相似文献   
145.
The purpose of our study is to see whether vaginal and cervical pH are helpful to screen for bacterial vaginosis and cervicitis during pregnancy. One hundred and seven pregnant women underwent prospectively both vaginal pH and cervical pH measurement and screening for microbial infections of the lower genital tracts at 10, 20 and 30 gestational week between February 1993 and August 1993. The value of vaginal pH significantly elevated in bacterial vaginosis (P < 0.05). Vaginal pH values also significantly elevated in patients who had had sexual intercourse 2 days before the dates of examinations (P < 0.01). Cervical pH value exhibited no significant change in bacterial vaginosis and cervicitis. Vaginal pH is a valid indicator for screening of bacterial vaginosis during pregnancy. However, vaginal pH might be influenced by the presence of semen. Cervical pH is not a useful parameter for screening of cervicitis during pregnancy.  相似文献   
146.
Concentrations of cortisol, corticosterone and cortisone in the plasma and adrenal glands, liver glycogen and plasma glucose of foetal, newborn and mother guinea-pigs were estimated during the last 6 days of pregnancy and throughout the first 24 h post partum. At the same time progesterone was measured in the plasma of the mother. During the prepartum rise in foetal plasma cortisol levels and liver glycogen, no significant change in the foetal adrenal cortisol content was observed. The plasma and adrenal cortisol concentrations of the mother were much higher than those observed in the foetus and increased significantly before parturition. In the mother as in the foetus, cortisone and corticosterone represent only a small percentage of corticosteroids compared with cortisol. These results indicate that the autonomous capacity of foetal adrenals, inhibited by maternal secretions before term, appears suddenly at birth.  相似文献   
147.
148.
The direct synthesis of gasoline-range iso-paraffins from synthesis gas (CO + H2, syngas) via a modified Fischer–Tropsch (FT) reaction was intensively studied under a wide range of reaction conditions by the combination of Co/SiO2 and Pd/beta in a consecutive dual reactor system. Results indicate that high selectivity of gasoline-range iso-paraffins (iso-paraffins relative to C4+ hydrocarbons was about 80%) could be achieved with the presence of Pd/beta catalyst in the lower reactor. Moreover, the performance of the Pd/beta catalyst for the titled reaction and the product composition can be significantly regulated by independently changing the reaction conditions such as catalyst amount, reaction temperature, and hydrogen partial pressure in the lower reactor. It was found that the Pd/beta catalyst used in this work was very active and stable even at a reaction temperature as low as 503 K. With the increase of hydrogen partial pressure in the lower reactor, the long-term stability of the Pd/beta catalyst was significantly enhanced.  相似文献   
149.
Efficient conversion of dimethyl ether (DME) into liquefied petroleum gas (LPG) with a hybrid catalyst is a novel method for semi-indirect synthesis of LPG fuel from syngas. The hybrid catalysts consisting of zeolite and hydrogenation catalyst were investigated in a fixed bed reactor. Experimental results demonstrated that the hybrid catalyst consisting of (Pd/SiO2) and USY efficiently converted DME into LPG and restrained decomposition of DME into CO and H2. With that catalyst, the one through conversion of DME reached about 100%, almost no CO and CO2 were produced and selectivity for LPG was more than 65%.  相似文献   
150.
1. The depressor response to sodium nitroprusside (SNP) and the pressor response to Nomega-nitro-L-arginine methyl ester (L-NAME) were investigated in anaesthetized and ganglion-blocked 6 week old (young) and 20 week old (adult) spontaneously hypertensive rats (SHR), and the results were compared with those in age-matched normotensive Wistar-Kyoto (WKY) rats. 2. SNP produced a dose-dependent decrease of the mean blood pressure (BP) in both strains, and no differences in vascular sensitivity to SNP were observed between the strains. 3. L-NAME caused dose-dependent pressor responses in both strains. The sensitivity and the maximal response to L-NAME in SHR were significantly greater than those in age-matched WKY (P< 0.05 or 0.01; t-test, 13 d.f. in both ages). However, there were no significant differences in the responses between ages in each strain. 4. Acute reduction of BP induced by 7-O-ethylfangchinoline did not affect the responses to SNP and L-NAME in the adult SHR. 5. These results indicate that a greater amount of NO is tonically released in SHR and that its contribution to BP control is greater in SHR than in WKY, whereas vascular sensitivity to NO does not differ between the strains. In addition, acute changes in BP do not affect the degree of dependency on NO for BP control.  相似文献   
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