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961.
962.
The purpose of this experimental pilot study was to determine the short- and long-term efficacy of directed verbal prompts and positive reinforcement on the level of eating independence (LEI) of elderly nursing home patients with dementia. Twenty-four subjects from a dementia unit were randomly selected and randomly assigned to three experimental groups and three control groups. The LEI scale was used to measure eating frequency and task performance at six consecutive meals during pretest and posttests, T2 and T3. During the treatment phase, which consisted of nine consecutive meals, prompts were administered to each experimental group and positive reinforcement was given when a subject completed eating tasks. Short-term effects were assessed on 2 consecutive days following treatment (T2) and long-term effects on 2 consecutive days, 7 days following treatment. Significant differences were found in eating performance but not in frequency. Experimental groups retained treatment at both posttests. The dementia diagnosis should not preclude the possibility that eating skills may be reacquired.  相似文献   
963.
OBJECTIVE: To compare the calculations of left ventricular mass according to thick-wall [American Society of Echocardiography (ASE) and Penn convention] and thin-wall (Wikstrand formula) models. METHODS: We have reexamined the data from the cross-sectional study on the general population sample of Vobarno and from a prospective longitudinal study of hypertensive patients assessing the prognostic significance of changes in left ventricular mass during a follow-up period of 10 years on average (Brescia population). RESULTS: For the Vobarno and Brescia populations, we found a close relationship between values of left ventricular mass calculated by using a thin-wall ellipsoidal model (Wikstrand formula) and those calculated using a thick-wall model with Penn convention or ASE left ventricle measurements (r = 0.99, for both the Vobarno and Brescia populations). Highest values of Penn left ventricle mass were slightly underestimated by use of the thin-wall formula. The numbers of nonfatal cardiovascular events and the relative risks, evaluated by Cox proportional hazard models for 151 patients seen at follow-up did not differ for patients with persistence of left ventricular hypertrophy (LVH), those with regression of LVH, and those with normal left ventricle mass, both at baseline and at follow-up, when these different ways of measuring left ventricle mass and partition values for LVH were used. CONCLUSIONS: The calculation of left ventricle mass according to the ASE recommendations or to the Penn convention, both of which are based on the assumption that the left ventricle can be represented by a prolate ellipsoid with both the internal and external long axes twice the short axis, produces results similar to those obtained using an alternate formula for the calculation of left ventricle mass, considering wall thickness constant around the ellipsoidal cavity. The cardiovascular risk stratification, in relation both to baseline left ventricular mass and to its change during long-term antihypertensive treatment, does not differ significantly among the results of these three different calculations.  相似文献   
964.
While vertebrate hemoglobins typically are tetrameric and show highly regulated and cooperative ligand binding, little is known of the evolution of these properties. We are studying the structural and functional properties of the hemoglobins from Caudina arenicola, an echinoderm. The echinoderms are in the lineage most closely related to the vertebrates to express hemoglobin. C. arenicola has three sets of red cells, in the water vascular system, the coelomic cavity, and in an intestinal vein. Each of these expresses a distinct array of globins. The hemoglobins are cooperative and exhibit unusual ligand-linked associative properties, being dimeric when oxygenated and forming tetramers and higher aggregates on deoxygenation. The major coelomic hemoglobins have been subjected to a detailed examination by a combination of ligand binding analyses and protein and DNA sequencing, as well as X-ray crystallography. Two typical globin introns were identified, along with a unique intron that bisects an N-terminal extension of the globin from the remainder of the gene. X-ray crystallographic analysis shows that the subunit interfaces of C. arenicola hemoglobins differ radically from those of vertebrate hemoglobins and indeed from some other invertebrate hemoglobins, but closely resemble the packing arrangements found in a clam hemoglobin (Scapharca). However, the residues implicated in cooperativity in these two types of hemoglobins differ substantially.  相似文献   
965.
BACKGROUND: The Texas Medication Algorithm Project (TMAP), a public-academic collaborative effort, is a 3-phase project to develop, implement, and evaluate medication treatment algorithms for public sector patients with schizophrenia, major depressive disorders, or bipolar disorders. DISCUSSION: This paper, the first in a series describing the activities of the TMAP, focuses on the various definitions and reasons why guidelines have gained popularity. Also discussed are their strengths, the limitations of the various methods used to develop them, and potential barriers to their implementation.  相似文献   
966.
The treatment of instability of the multiply reoperated knee is a complex problem. The causes for failure are numerous and include repeated trauma, insufficient fixation and non-anatomic placement of the graft, inadequate replacement material, isolated anterior cruciate ligament (ACL) reconstruction in complex knee instability or the use of a ligament prosthesis. With every surgical procedure, however, the anatomical and technical conditions become worse. Problems like degenerative changes, joint stiffness and gait abnormalities occur and often become a more focal point than the instability itself. The purpose of this paper is to present the problems and the dilemma of instability of the multiply reoperated knee and the possible solutions. Between 1976 and 1996, a total of 1752 ACL reconstructions were carried out in Munich and Hannover. Of these, 228 (13%) were revision, mostly of failed ACL reconstructions performed elsewhere. Since 1989, we have chosen the severest cases from this group (more than three operations on the same knee) for this study. Seventeen patients were investigated who had undergone up to 25 operations. The mean number of operations was 7. All primary operations were performed in other hospitals. In 10 cases only the ACL reconstruction was performed as a final procedure, mostly in combination with other procedures like medial meniscus replacement, extra-articular stabilization or arthrolysis. In the other cases operations such as osteotomies, arthrodesis or amputation were necessary. The results present the main dilemma in instability of the multiply reoperated knee since they were not successful in all patients. Finally, 15 patients report still having instability, pain or swelling in isolation or in combination. Nine patients were satisfied with their subjective results. Even after the socalled definitive procedures, certain complications arose. The main goal in the treatment of instability of the multiply reoperated knee is to avoid a series of operations, hospitalization and history of illness. General revision surgery for the entire complaint is not the aim of the treatment. The specific problem of the patient should be extracted from the complex situation, and this should be solved with the most limited procedure possible only.  相似文献   
967.
1. Mechanical forces associated with blood flow play important roles in the acute control of vascular tone, the regulation of arterial structure and remodelling and the localization of atherosclerotic plaque. Uraemia is a proatherogenic process and is expected to be associated with impaired vascular reactivity.2. To study this, 12 male Wistar rats were rendered uraemic by five-sixths nephrectomy and 12 control rats were sham operated simultaneously. After 8 weeks a tail-cuff systolic blood pressure was recorded, blood samples were taken and the animals killed. Isolated femoral arteries were dissected and mounted on a pressure myograph and myogenic tone was assessed over a range of intravascular pressures from 40 to 160 mmHg. Histologically the arteries were comparatively examined for gross morphology, calcification and deposition of collagen.3.Biochemically the serum urea and creatinine were greater in the uraemic compared with the control rats (urea: 23.5+/-6 mmol/l and 6.8+/-01 mmol/l respectively, P not significant; creatinine: 130.7+/-13 mmol/l and 70.3+/-5 mmol/l respectively, P<0.01) but systolic blood pressure was the same in both groups (control, 97+/-1 mmHg; uraemic, 98+/-2 mmHg), compatible with mild uraemia.4. Myogenic tone was significantly greater in uraemic vessels (7.3+/-1.8% versus 2.3+/-0. 4% in control, P=0.01). The actual vessel lumen diameter was also smaller in pressurized uraemic vessels compared with control vessels (471+/-30 microm versus 604+/-33 microm, P<0.01) after equilibration in physiological salt solution. However, when incubated in calcium-free physiological salt solution, the passive internal diameter was similar in uraemic vessels (538+/-25 microm compared with 595+/-31 microm in control). Histologically, there were no differences between the two groups.5. We conclude that some aspects of vascular reactivity are altered in mild experimental uraemia as shown by a reduced internal lumen diameter and increased myogenic tone. Furthermore, these changes are apparent in the absence of hypertension and precede structural changes.  相似文献   
968.
969.
970.
Recent studies suggest that local levels of sympathetic nervous activity influence the growth of prostatic tissue. In several epidemiological studies, resting heart rate, an indicator of overall sympathetic activity, was positively associated with all noncardiovascular and cancer death among men. However, no previous analyses have focused on the specific relationship of heart rate to prostate cancer mortality. We studied 22,380 men enrolled in the Chicago Heart Association cohort from 1967-1973, who had heart rate (HR) determined by electrocardiogram. Mean length of follow-up (for mortality) was 19.2 years. We computed age-adjusted rates for prostate cancer death by variable of interest and fitted proportional hazards models to estimate relative risks (RRs) adjusted for potential confounders. In a model controlling for age, body mass index, blood pressure, serum cholesterol, smoking, postload plasma glucose, and years of education, the RR for a 10 beat/min higher HR was 1.26 (95% confidence interval = 1.04-1.51). Age-adjusted RRs across higher quintiles for HR were 1.00, 1.55, 1.85, 2.18, and 2.69 (P trend = 0.006). Survival curves indicated that the elevated risk was not confined to the early years of follow-up. Because little is known about factors that determine risk of prostate cancer death, these results could prove important even if due to an unmeasured etiological factor other than heart rate itself. The results are consistent with the hypothesis that local neurotrophic factors associated with sympathetic activity influence the progression of prostate cancer  相似文献   
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