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151.
Eighty patients underwent open-heart surgery from March 1990 to March 1993. We used combined aortic root (antegrade)/coronary sinus (retrograde) perfusion for cardioplegia delivery as a means of myocardial protection. The special retroplegia cannula was introduced to the coronary sinus (CS) in 67 patients by the transatrial (blind intubation) after one cannula cava insertion; the CS was cannulated under direct vision by right atriotomy after bicaval cannulation in 13 patients. Varied and prolonged cardiac procedures were done using cooled crystalloid cardioplegia (4 centigrades + potassium) except in one patient with severe ventricular damage in whom warm blood cardioplegia was infused. There was no CS or cardiac vein damage or disruption. There was no A-V blockade. The CS was intubated easily in all cases and cardioplegia solution readily infused. Coronary sinus pressure never exceeded 40 mm Hg. Overall hospital mortality (30 days postoperative) was 3.75% (3 cases). Sepsis was the cause of death in 2 patients and stroke in one. Inotropes were used in few cases as a means of renal protection. We conclude that the combined antegrade/retrograde cardioplegia delivery can be used routinely in most patients undergoing open-heart surgery. 相似文献
152.
R Lagos P Herrera A Sepúlveda A Mu?oz C Benavente I Bravo T Lamberg 《Canadian Metallurgical Quarterly》1996,124(10):1211-1218
BACKGROUND: Urinary tract infections in children are associated with functional and anatomical abnormalities of the urinary tract, they tend to recur and can cause permanent kidney damage. AIM: To study in children with urinary tract infections, microbiological factors associated to recurrence, functional and anatomical abnormalities of the urinary tract. PATIENTS AND METHODS: A prospective sample of children was incorporated into a follow-up protocol after their first episode of bacteriologically-demonstrated urinary tract infection. In all patients an abdominal ultrasound examination and a mictional urethrocystography were done and the presence of fimbriae was studied in isolated strains of Escherichia coli. RESULTS: Two hundred fifteen cases bad an adequate adherence to the study protocol, 190 caused by E coli. Fimbriated E coli strains were isolated with greater frequency from children with pyelonephritis than from those with a low urinary tract infection (50 and 28% respectively). The absence of fimbriae in E coli strains was associated with a higher risk of recurrent infections (odds ratio = 3, confidence intervals = 2-9.2) and an abnormal urethrocystography (odds ratio = 3, confidence intervals = 1.1-10.2). CONCLUSIONS: These data are consistent with foreign reports and support the need to study adhesins in E coli strains isolated from children with urinary tract infections. 相似文献
153.
FJ Rupérez C Barbas M Castro S Martínez E Herrera 《Canadian Metallurgical Quarterly》1998,823(1-2):483-487
A method for vitamin E (alpha-tocopherol) measurement in rat adipose tissue and mammary gland has been developed and validated. Tissues were homogenized in ethanol-water (1:1) and extracted with n-hexane. Vitamin K1 was used as internal standard. Separation was performed by HPLC with methanol-water (96.5:3.5) as eluent in a Nucleosil C18 column (15 x 0.46 cm) at 40 degrees C. Detection was by fluorescence with excitation at 295 nm and emission at 350 nm for vitamin E and at 330 and 440 nm for vitamin K1. Standards and tissue extracts were checked for linearity giving correlation coefficients over 0.99 in a range of concentrations from 0.56 to 4.51 nmol/g in adipose tissue and from 2.18 to 17.4 nmol/g in mammary gland tissue. Intra-assay precision (R.S.D.) varied between 3 and 4%, whereas inter-assay precision was between 8 and 9%. Recoveries ranged between 95 +/- 3% and 98 +/- 11% for the two tissues, respectively. Vitamin E was measured in rats that had previously received one oral dose of this vitamin. Whereas vitamin E content in adipose tissue did not differ between late-pregnant and virgin rats, it was significantly higher in mammary gland of pregnant rats, and this difference could be related to the enhanced lipoprotein lipase activity in this group. 相似文献
154.
Ismael Herrera 《Advances in Engineering Software》1995,24(1-3):43-56
The author's algebraic theory of boundary value problems has permitted systematizing Trefftz method and expanding its scope. The concept of TH-completeness has played a key role for such developments. This paper is devoted to revise the present state of these matters. Starting from the basic concepts of the algebraic theory, Green-Herrera formulas are presented and Localized Adjoint Method (LAM) derived. Then the classical Trefftz method is shown to be a particular case of LAM. This leads to a natural generalization of Trefftz method and a special class of domain decomposition methods: Trefftz-Herrera domain decomposition. 相似文献
155.
156.
Daniel S. Mitchell Walter R. Rogers William R. Herrera Walter G. Switzer 《Fire Safety Journal》1978,1(3):187-197
Thirty Long-Evans rats served in each of six experiments to determine the time-course of behavioral incapacitation during exposure to full-scale combustion of household furnishings. Three experiments involved furniture constructed of natural-fiber materials, and three experiments involved furniture dominated by synthetic polymers. Groups of rats, previously trained to stable levels of performance on three tasks (rotorod, operant shock-avoidance, and a jump/escape test), were exposed to combustion products at three locations in a full-scale burn facility. Animals were removed from the exposure environment when they reached each of three operationally defined stages of behavioral incapacitation. Measures of time-to-incapacitation revealed that a given degree of behavioral dysfunction occurred 3 to 5 times sooner during exposure to the combustion of polymeric as compared to natural-fiber furnishings. Temperature, hydrocarbons, carbon dioxide, and oxides of nitrogen were the most frequent statistically significant correlates of time to behavioral incapacitation in polymeric fires; carbon monoxide, carbon dioxide, and total hydrocarbon concentration were the most frequent statistically significant correlates of behavioral dysfunction in natural-fiber fires. Animals that survived the first 24-hour interval after exposure showed no evidence of lasting behavioral incapacitation. 相似文献
157.
The easy and economic way of designing diets with differrent protein contents is pointed out. It was studied the effect of diets with 27%, 18%, 9%, 4,5% and 0% of proteins on body weight, liver weight and liver protein content through their administration to white 21 day old rats for 7 or 14 days. An effect of dietetic protein deficit on one out of these variables was evidenced. 相似文献
158.
Juan M. Martínez Moreno C. Gómez Herrera E. Márquez Delgado C. Janer Del Valle L. Duran Hidalgo 《Journal of the American Oil Chemists' Society》1960,37(11):582-587
Expressed olive juice contains emulsified globules of olive oil. Electron photomicrographs of these globules show a rough
membrane protecting them against coalescence. Some features of the membranes, such as the existence of “poles” and deposited
microcrystals, are disclosed by the photographs and by electron diffraction patterns. Heavy metals appear to concentrate in
the membranes and not in the aqueous medium.
Presented at the 50th annual spring meeting, American Oil Chemists' Society, New Orleans, La., April 20–22, 1959. 相似文献
159.
JM Serletti SL Moran GS Orlando T O'Connor HR Herrera 《Canadian Metallurgical Quarterly》1998,102(6):1947-1953
The incidence of free-flap failure is reported at 4 to 5 percent. Often, these failures are attributed to postoperative venous thrombosis with salvage rates reported at 42 percent. The use of thrombolytics has been effective in laboratory protocols; however, there have been only case reports to substantiate their use in humans. In this study, we establish a protocol for the administration of urokinase for postoperative venous thrombosis. Upon clinical evidence of venous thrombosis, all patients were urgently returned to the operating room, where the venous anastomosis was resected and a new venous anastomosis was performed. A solution of 250,000 units of urokinase was then infused over 30 minutes through a 25-gauge butterfly inserted into the recipient artery just proximal to the arterial anastomosis. Patients were continued on a daily aspirin (325 mg). More than 600 free flaps have been performed by our group since 1990. In that group of patients, five were diagnosed with postoperative venous thrombosis. Flaps consisted of four radial forearm flaps and one free transverse rectus abdominis muscle flap. All patients were diagnosed late based upon significant changes within the flap. Thromboses were clinically apparent on postoperative days 1 through 6, with an average of 3.6 days. All five patients received urokinase as described. The average age of the patients treated was 43. There were no postoperative hematomas, blood transfusions, or bleeding complications. There were no allergic or anaphylactic reactions to the urokinase. All flaps survived (100 percent) with a mean follow-up of 27 months. The use of urokinase as described in our protocol has been an effective thrombolytic, capable of reversing clinically advanced venous thrombosis when combined with repeated venous anastomosis. We believe this protocol provides a viable option for the treatment of postoperative venous thrombosis. 相似文献
160.
RR Lozano-Salazar MF Herrera F Vargas-Vorácková X López-Karpovitch 《Canadian Metallurgical Quarterly》1998,176(4):366-369
Erythrokeratodermia variabilis (EKV, OMIM 133200) is an autosomal dominant genodermatosis with considerable intra- and interfamilial variability. It has a disfiguring phenotype characterized by the independent occurrence of two morphologic features: transient figurate red patches and localized or generalized hyperkeratosis. Both features can be triggered by external factors such as trauma to the skin. After initial linkage to the RH locus on 1p, EKV was mapped to an interval of 2.6 cM on 1p34-p35, and a candidate gene (GJA4) encoding the gap junction protein alpha-4 (connexin 31, Cx31) was excluded by sequence analysis. Evidence in mouse suggesting that the EKV region harbours a cluster of epidermally expressed connexin genes led us to characterize the human homologues of GJB3 (encoding Cx31) and GJB5 (encoding Cx31.1). GJB3, GJB5 and GJA4 were localized to a 1.1-Mb YAC in the candidate interval. We detected heterozygous missense mutations in GJB3 in four EKV families leading to substitution of a conserved glycine by charged residues (G12R and G12D), or change of a cysteine (C86S). These mutations are predicted to interfere with normal Cx31 structure and function, possibly due to a dominant inhibitory effect. Our results implicate Cx31 in the pathogenesis of EKV, and provide evidence that intercellular communication mediated by Cx31 is crucial for epidermal differentiation and response to external factors. 相似文献