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91.
92.
BACKGROUND: Lack of information about the effect of insurance coverage on the demand for and use of smoking-cessation services has prevented widescale adoption of coverage for such services. METHODS: In a longitudinal, natural experiment, we compared the use and cost effectiveness of three forms of coverage with those of a standard form of coverage for smoking-cessation services that included a behavioral program and nicotine-replacement therapy. The study involved seven employers and a total of 90,005 adult enrollees. The standard plan offered 50 percent coverage of the behavioral program and full coverage of nicotine-replacement therapy. The other plans offered 50 percent coverage of both the behavioral program and nicotine-replacement therapy (reduced coverage), full coverage of the behavioral program and 50 percent coverage of nicotine-replacement therapy (flipped coverage), or full coverage of both the behavioral program and nicotine-replacement therapy. RESULTS: Estimated annual rates of use of smoking-cessation services ranged from 2.4 percent (among smokers with reduced coverage) to 10 percent (among those with full coverage). Smoking-cessation rates ranged from 28 percent (among users with full coverage) to 38 percent (among those with standard coverage). The estimated percentage of all smokers who would quit smoking per year as a result of using the services ranged from 0.7 percent (with reduced coverage) to 2.8 percent (with full coverage). The average cost to the health plan per user who quit smoking ranged from $797 (with standard coverage) to $1,171 (with full coverage). The annual cost per smoker ranged from $6 (with reduced coverage) to $33 (with full coverage). The annual cost per enrollee ranged from $0.89 (with reduced coverage) to $4.92 (with full coverage). CONCLUSIONS: Use of smoking-cessation services varies according to the extent of coverage, with the highest rates of use among smokers with full coverage. Although the rate of smoking cessation among the benefit users with full coverage was lower than the rates among users with plans requiring copayments, the effect on the overall prevalence of smoking was greater with full coverage than with the cost-sharing plans.  相似文献   
93.
The operation of a microwave cryogenic sapphire resonator oscillator presenting an exceptional frequency stability for long integration times has been demonstrated. Based on a very simple design the 11.5 GHz oscillator presents a fractional frequency instability lower than 6/spl times/10/sup -14/ over one day.  相似文献   
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95.
The divalent cation selective ionophores A23187 and ionomycin were compared for their effects on the Ca2+ contents, nucleotide contents, and protein synthetic rates of several types of cultured cells. Both ionophores reduced amino acid incorporation by approximately 85% at low concentrations (50-300 nmol/L) in cultured mammalian cells without reducing ATP or GTP contents. At these concentrations A23187 and ionomycin each promoted substantial Ca2+ efflux, whereas at higher concentrations a large influx of the cation was observed. Ca2+ influx occurred at lower ionophore concentrations and to greater extents in C6 glioma and P3X63Ag8 myeloma than in GH3 pituitary cells. The ATP and GTP contents of the cells and their ability to adhere to growth surfaces declined sharply at ionophore concentrations producing increased Ca2+ influx. Prominent reductions of nucleotide contents occurred in EGTA-containing media that were further accentuated by extracellular Ca2+. Ionomycin produced more Ca2+ influx and nucleotide decline than comparable concentrations of A23187. The inhibition of amino acid incorporation and mobilization of cell-associated Ca2+ by ionomycin were readily reversed in GH3 cells by fatty acid-free bovine serum albumin, whereas the effects of A23187 were only partially reversed. Amino acid incorporation was further suppressed by ionophore concentrations depleting nucleotide contents. Mitochondrial uncouplers potentiated Ca2+ accumulation in response to both ionophores. At cytotoxic concentrations Lubrol PX abolished protein synthesis but did not cause Ca2+ influx. Nucleotide depletion at high ionophore concentrations is proposed to result from increased plasmalemmal Ca2+-ATPase activity and dissipation of mitochondrial proton gradients and to cause intracellular Ca2+ accumulation. Increased Ca2+ contents in response to Ca2+ ionophores are proposed as an indicator of ionophore-induced cytotoxicity.  相似文献   
96.
Some developments in the Computer Science Department at the University of Manchester that influenced its growth from a premodern engineering-oriented department to a large, complex department with a range of interdisciplinary research activities that span most aspects of computer science are outlined. The changes in patterns of research output, recruitment of academic staff, and sources of research funding are discussed. It is argued that the Department became what can be considered to be a modern research-oriented enterprise, widening the scope of its research, its connections with industry and other academic departments, and its interdisciplinary research because of internal policies as well as external influences, such as government policy  相似文献   
97.
We report a case of short stature associated with high circulating levels of insulin-like growth factor (IGF)-binding protein-1 (IGFBP-10 and low levels of IGF-II responsive to pharmacological treatment with GH. Our patient suffered severe growth failure from birth (2.06 SD below the mean for normal full-term boys, and 5.2 and 7.3 SD below the mean at 5 and 10 months). Studies carried out before referral to our pediatric unit included normal 46,XY karyotype and normal encephalic imaging. Other endocrine and metabolic alterations and other systemic diseases were excluded. At 1.7 yr of age (length, 6.1 SD; weight, 4.6 SD; head circumference, 1.4 SD below the mean, respectively) the patient was referred to our pediatric unit. The baseline GH concentration was 31 microg/L, and the peak after an arginine load was 59.6 microg/L. In the same samples GH bioactivity was nearly superimposable (RIA/Nb2 bioactivity ratio = 0.9). Fasting insulin and glucose concentrations were 7.4 microU/mL and 65 mg/dL, respectively, both normally responsive to an oral glucose load. GH insensitivity was excluded by a basal IGF-I concentration (64 ng/mL) in the normal range for 0- to 5-yr-old boys and its increase after 2 IU/day hGH administration for 4 days. IGFBP-3 (0.5 microg/mL) was slightly reduced, whereas IGFBP-1 (2218 and 1515 ng/mL in two different basal samples) was well above the normal values for age and was suppressible by GH (maximum suppression, -77% at 84 h) and glucose load (maximum suppression, -46% at 150 min). The basal IGF-II concentration was below the normal range (86 ng/mL), whereas IGFBP-2 was normal (258 ng/mL). Analysis of the promoter region of IGFBP-1 and IGF-II failed to find major alterations. Neutral gel filtration of serum showed that almost all IGF-I activity was in the 35- to 45-kDa complex, coincident with IGFBP-1 peak, while the 150-kDa complex was absent, although the acid-labile subunit was normally represented. At 2.86 yr (height, 65.8 cm; height SD score, -7.3; height velocity SD score, -5) the patient underwent treatment with 7 IU/week human GH; after 4 months, the patient's height was 68.5 cm (height SD score, -6.9) corresponding to a growth velocity of 8.3 cm/yr (0.3 height velocity SD score). IGFBP-1 was reduced (216 ng/mL), although still in the high range, whereas IGF-I (71 ng/mL), IGFBP-3 (0.62 microg/mL), and IGF-II (111 ng/mL) were only slightly increased. The IGF-I profile showed activity in the 150-kDa region. In conclusion, we speculate that the increased IGFBP-1 values found in this patient produce 1) inhibition of IGF-I biological activity and, therefore, a resistance to IGF-I not due to a receptor defect for this hormone; 2) inhibition of formation of the circulating 150-kDa ternary complex and, therefore, an accelerated clearance rate of IGF peptides; 3) inhibition of the feedback action on GH, leading to increased GH levels, which could suggest the diagnosis of GH insensitivity syndrome; and 4) inhibition of body growth.  相似文献   
98.
99.
OBJECTIVES: This study investigated the value of sestamibi scintigraphy in assessing residual ischemia after anterior myocardial infarction. BACKGROUND: Serial imaging with sestamibi, the uptake and retention of which correlate with regional myocardial blood flow and viability, has been used to estimate salvaged myocardium and risk area after acute infarction. We recently documented that recovery of perfusion and contraction in the infarcted area may continue well after the subacute phase, suggesting myocardial hibernation. Some underestimation of viability in the setting of hibernating myocardium by sestamibi imaging has been reported. METHODS: We studied 58 patients in stable condition after Q wave anterior infarction. Regional perfusion and function were quantitatively assessed by sestamibi tomography and two-dimensional echocardiography at 4 to 6 weeks and at 7 months after infarction. In sestamibi polar maps, abnormal areas with tracer uptake > 2.5 SD below our reference values were computed at rest and after symptom-limited exercise. On two-dimensional echocardiography the ejection fraction and extent of rest wall motion abnormalities were assessed by a computerized system. All patients had coronary angiography between the two studies. RESULTS: At 7 months the extent of rest sestamibi defect was significantly reduced in 40 patients (69%, group 1) and unchanged in 18 (31%, group 2). Rest wall motion abnormalities and ventricular ejection fraction significantly improved in group 1 but not in group 2. Underlying coronary disease, patency of the infarct-related vessel and rest sestamibi defect extent at 5 weeks were comparable between the two groups. At 7 months, an increase in the reversible (stress-rest defect) tracer defect was observed in group 1 (p < 0.05) despite a smaller stress-induced hypoperfusion (p < 0.05). Reversible sestamibi defects and stress hypoperfusion were unchanged in group 2. In 38 (95%) of 40 group 1 patients, the area showing reversible sestamibi defects at 7 months matched the area showing fixed hypoperfusion at 5 weeks. CONCLUSIONS: The reduction in the rest tracer uptake defect that can occur late after infarction may affect the assessment of ischemic burden by sestamibi imaging early after anterior myocardial infarction.  相似文献   
100.
Eighty children who in the first 2 years of life had signs and symptoms relating to a cerebral neoplasm were studied over an 18-year period (1970-1987), the mean follow-up being 8.2 years. In each case age at onset, clinical presentation, tumor location and pathological diagnosis, extent of surgical resection, postoperative mortality, adjuvant therapy length of survival and quality of life were assessed. Supratentorial tumors (59%) were more common than infratentorial. The most frequent clinical presenting feature (70%) was increased intracranial pressure. Sixty-three patients (79%) were operated on and in all of these cases a histological diagnosis was obtained. Astrocytomas (41%) and medulloblastomas (20%) were the most common oncotypes. Surgical mortality was 17.4% and the 5-year survival rate was 54%. Quality of life was assessed for all long-term surviving patients using a specifically designed protocol. Normal physical and intellectual performances were found in 46% of cases, and all together 75% of the patients had sufficient autonomy in daily life. The prognosis is more closely related to tumor location and type of treatment than to histological diagnosis or age at onset.  相似文献   
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