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101.
Global interconnects have been identified as a serious limitation to chip scaling, due to their latency and power consumption. We demonstrate a scheme to overcome these limitations, based on the utilization of upper-level metals, combined with structured communication architecture. Microwave style transmission lines in upper-level metals allow close-to-velocity-of-light delays if properly dimensioned. As an example, we demonstrate a 480-/spl mu/m-wide and 20-mm-long bus with a capacity of 320 Gb/s in a nearly standard 0.18-/spl mu/m process. The process differs from a standard process only through a somewhat thicker outer metal layer. We further illustrate how "self pre-emphasis" at the launch of a data pulse can be used to double the maximum available data rate over a wire. The proposed techniques are scalable, given that higher level metals are properly dimensioned in future processes.  相似文献   
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103.
High-frequency lasers have been flip-chip mounted on silicon motherboards. Small-signal modulation bandwidths around 24 GHz were obtained. It was shown that the bandwidth was not limited by extrinsic parasitics associated with the mounting scheme. Lasers were passively aligned to single mode fibers in V-grooves with the self-aligning solder bump technique. By passive alignment 50% of maximum coupling efficiency obtained by active alignment was achieved.  相似文献   
104.
The aim of the study was to identify factors of decisive importance for women's motivation to perform breast self-examination (BSE), which could form the basis of an intervention programme. Interviews were conducted in 1994 with 48 women focusing on four different areas: 1) why the women examined did not examine their breasts, 2) the influence of their upbringing, 3) information or education previously received about the method of examination, and 4) other types of self-care. The findings were summarized under the following categories: feelings, experiences, and lifestyle. Anxiety/fear of discovering a lump and faith/trust in one's own ability to perform the examination were dominating factors influencing the practice or non-practice of BSE. However, there was a general need for knowledge, theoretical as well as practical, among the women studied. They also needed help to identify a strategy to enable them to remember to perform the examination. In order to make BSE a habit, education about BSE ought to be provided to girls at school. The important role of nurses in teaching women to examine their breasts themselves and in reminding them to perform the examination was emphasized.  相似文献   
105.
Legislation requires labelling of foods containing allergic ingredients, amongst them celery, mustard and sesame. Here we present robust quantitative and sensitive methods for real-time PCR detection of celery, mustard (Sinapis alba and Brassica sp.) and sesame in food. The development of the DNA-based assays was part of an effort to generate alternative detection methods for allergens for which effective protein-based assays are lacking. The celery and sesame methods were specific for the celery mannitol dehydrogenase gene and the sesame allergen encoding 2S albumin gene, respectively, when tested against a range of plant materials. The mustard method was specific for the allergen encoding sinA gene and its homologues present in different Brassica sp. All primer probe pairs gave high amplification efficiency and sensitivities below approximately ten molecules of purified template DNA. These DNA-based detection methods will constitute supplementary and complementary methods to the traditional protein-based methods. Laboratories may choose different analysis formats depending on the food matrix, the availability of specific tests and the performance characteristics of the tests.  相似文献   
106.
OBJECTIVE: To compare the efficacy and tolerability of mibefradil and amlodipine in patients with uncomplicated mild-to-moderate essential hypertension. DESIGN: A double-blind, randomised, parallel group multicentre trial. METHODS: 239 patients received 50 mg mibefradil or 5 mg amlodipine for 4 weeks, followed by a forced titration to 100 mg mibefradil or 10 mg amlodipine for an additional 8 weeks. Patients then entered a 4-week withdrawal period either on therapy or switched to placebo. RESULTS: Statistically equivalent reductions in trough sitting diastolic blood pressure (SDBP) were observed after 12 weeks of once-daily treatment with 50/100 mg mibefradil (-11.5 +/- 8.2 mm Hg) and 5/10 mg amlodipine (-13.2 +/- 7.9 mm Hg). The number of patients with normalised SDBP (< or = 90 mm Hg) increased 23.3% in the mibefradil group and 19.5% in the amlodipine group (approximately 74% in both groups). Patients on mibefradil or amlodipine during the withdrawal period had significantly larger decreases in SDBP than those on placebo. Patients on mibefradil had a decrease in heart rate of 5.5 bpm. Patients on amlodipine had no change in heart rate; however, cessation of amlodipine was associated with a decrease in heart rate. CONCLUSIONS: Mibefradil was as effective as amlodipine in reducing BP; both compounds were effective treatments of hypertension.  相似文献   
107.
Mechanical loading of the cervical spine during car accidents often lead to a number of neck injury symptoms with the common term Whiplash Associated Disorders (WAD). Several of these symptoms could possibly be explained by injuries to the cervical spinal nerve root region. It was hypothesised that the changes in the inner volume of the cervical spinal canal during neck extension-flexion motion would cause transient pressure changes in the CNS as a result of hydro-dynamic effects, and thereby mechanically load the nerve roots and cause tissue damage. To test the hypothesis, anaesthetised pigs were exposed to experimental neck trauma in the extension, flexion and lateral flexion modes. The severity of the trauma was kept below the level where cervical fractures occur. Transient pressure pulses in the cervical spinal canal were duly recorded. Signs of cell membrane dysfunction were found in the nerve cell bodies of the cervical spinal ganglia. Ganglion injuries may explain some of the symptoms associated with soft-tissue neck injuries in car accidents. When the pig's head was pulled rearward relative to its torso to resemble a rear-end collision situation, it was found that ganglion injuries occurred very early on in the neck motion, at the stage where the motion changes from retraction to extension motion. Ganglion injuries did not occur when pigs were exposed to similar static loading of the neck. This indicates that these injuries are a result of dynamic phenomena and thereby further supports the pressure hypothesis. A Neck Injury Criterion (NIC) based on a theoretical model of the pressure effects was developed. It indicated that it was the differential horizontal acceleration and velocity between the head and the upper torso at the point of maximum neck retraction that determined the risk of ganglion injuries.  相似文献   
108.
109.
The relationship between the level of dehydration (3%, 6%, and 8% body weight) and the preference for water and saline in the rehydration were assessed in rats for 15 h. At the 6% and 8% dehydration levels, rats provided with tap water and 0.9% NaCl solution simultaneously consumed more water than NaCl solution (calculated Na concentration was about 57 mEq/l) within 3 h and then consumed more NaCl solution than water (about 116 mEq/l). The shift of the Na concentration of fluid occurred when about 107% of lost cations and 82% of lost fluid were regained. Urine output and urinary Na output were about 14% of the ingested fluid during the initial 4 h; after that, the output was in amounts almost equal to the ingestion. However, the 3% dehydrated rats consumed almost equal amount of tap water and NaCl solution (about 68 mEq/l) throughout the 15 h. The result indicates that at more than 3% dehydration level, rats initially choose hypotonic NaCl solution, and the volume loss of body fluid is then regained by the consumption of almost isotonic Na solution.  相似文献   
110.
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