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721.
OBJECTIVES: This study sought to evaluate the association of drug use with disability in a representative sample of the US household population. METHODS: The use of illicit drugs and alcohol reported by respondents in the 1991 National Household Survey on Drug Abuse who identified themselves as "disabled, unable to work" was compared with respondents without disabilities. RESULTS: Among younger adults (18-24 years), persons with disabilities were more likely than those without disabilities to report that they had used heroin (adjusted odds ratio [OR] = 6.89; 95% confidence interval [CI] = 1.35, 35.1) or crack cocaine (OR = 6.38; 95% CI = 1.05, 38.6). Among older adults (35 years and older), persons with disabilities were more likely to report the use of sedatives (OR = 2.46; 95% CI = 1.21, 4.94) or tranquilizers (OR = 2.18: 95% CI = 1.08; 4.42) not medically prescribed. CONCLUSIONS: These results suggest that use of illicit drugs is a potentially serious problem among persons with disabilities and requires both research and clinical attention. 相似文献
722.
SF Cleary 《Canadian Metallurgical Quarterly》1993,54(4):178-185
In vitro studies of effects of low-frequency (LF) electromagnetic (EM) fields have revealed a variety of sensitive cell-physiologic end-points. Effects have been reported on (1) DNA, RNA, and protein synthesis; (2) cell proliferation; (3) cation fluxes and binding; (4) immune responses; and (5) membrane signal transduction (i.e., hormones, enzymes, and neuro-transmitters). Typically such effects occurred as a result of short-term exposure of cells to EM at frequencies of 100 Hz or less and at low field intensities. The dependency on frequency or modulation, as well as the apparent weak cellular interaction of these LF EM fields, lacks theoretic explanation. It has not been determined whether effects are induced by electric or magnetic fields. Confounding interpretation of the results are phenomena such as (1) transient or time-delayed responses; (2) modulation- and intensity-specific effects, referred to as modulation or intensity "windows;" and (3) general lack of dose- (or dose-rate) response data or EM field thresholds. Consequently, although it is well-established that LF EM fields affect biological systems in vitro, use of these data to assess human health effects is limited. This paper reviews selected published reports of LF EM fields on in vitro systems. Where possible, relevance of the findings to occupational exposures will be assessed, principally by considering the consistency of in vitro and in vivo EM exposure effects and comparison of EM field intensities that affect in vitro systems with occupational EM exposure intensities. Finally, suggestions will be made for the direction of future in vitro research of direct pertinence to potential occupational exposure problems. 相似文献
723.
NM Lakkis SF Nagueh NS Kleiman D Killip ZX He MS Verani R Roberts WH Spencer 《Canadian Metallurgical Quarterly》1998,98(17):1750-1755
BACKGROUND: Left ventricular outflow tract (LVOT) obstruction is frequently responsible for symptoms in hypertrophic obstructive cardiomyopathy (HOCM). Medical therapy is often not sufficient to control these symptoms, and surgical myotomy-myomectomy is required. METHODS AND RESULTS: We enrolled 33 symptomatic patients with HOCM and obstruction (>/=40 mm Hg gradient at rest or >/=60 mm Hg dobutamine-provoked). By contrast echocardiography, the bulging septum was localized and infarcted by injection of 2 to 5 mL of absolute ethanol into the septal artery(ies) supplying the hypertrophied area. Baseline echocardiograms with Doppler, myocardial perfusion tomograms, and treadmill exercise or pharmacological testing were compared with those at 6 weeks and 6 months. The mean rise in creatine kinase was 1964+/-796 U. All patients experienced symptomatic relief; NYHA class decreased from 3. 0+/-0.5 to 0.9+/-0.6 (P<0.001). Exercise time increased from 286+/-193 to 421+/-181 seconds (P=0.03). The resting and dobutamine-provoked gradient decreased from 49+/-33 and 96+/-34 mm Hg to 9+/-19 (P<0.001) and 24+/-31 mm Hg (P<0.001), respectively. Echocardiograms repeated at 6 weeks after the procedure showed a 28% reduction in septal thickness and 17% reduction in left ventricular mass. Myocardial perfusion imaging showed a "septal amputation pattern," with scarring in the upper and middle septal areas. Complete heart block developed in 11 patients, who then required permanent pacemaker implantation. CONCLUSIONS: Echocardiography-guided ethanol septal reduction in patients with HOCM is a safe, minimally invasive procedure that provides symptomatic relief with improved hemodynamic and left ventricular parameters. 相似文献
724.
Infection in a peripheral vascular prosthesis continues to be a serious complication in arterial reconstructive surgery and threatens the patient with loss of either limb or life. Infection rates at major centers are now low, ranging from 1 to 6 percent; however, limb loss and mortality rates for this complication range from 25 to 75 percent depending on the location of the graft and the extent of the infection. The use of muscle flaps in the management of acute wounds, infection-prone wounds, exposed orthopedic hardware, and osteomyelitis is now commonplace. Transposed muscle has been shown to be well-vascularized tissue that improves healing time and decreases local wound bacterial counts. After considering the preceding facts, we used muscle flaps for coverage of infected peripheral vascular prostheses in a highly select group of patients. These patients were "end of the line," and last-ditch efforts were made to salvage life or limb. Twenty-four infected vascular grafts in 20 patients have been analyzed. Ages ranged from 52 to 87 years. All patients had grade 3, stage I, II, or III peripheral graft infections, as previously defined by Szilagyi and modified by vonDongen. Aortofemoral reconstruction was the most common initial bypass procedure (14), followed by femoral popliteal (6), axillofemoral (2), iliofemoral (1), and subclavian/subclavian bypass (1). Staphylococcus aureus was the most common infecting organism. Muscles used for coverage were the rectus femoris (13), the sartorius (9), the rectus abdominis (1), and the pectoralis major (1). The graft material was composed of Dacron in 16 instances and polytetrafluoroethylene in 8.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
725.
We report a rational synthesis of maghemite (γ-Fe2O3) short-nanotubes (SNTs) by a convenient hydrothermal method and subsequent annealing process. The structure, shape, and magnetic
properties of the SNTs were investigated. Room-temperature and low-temperature magnetic measurements show that the as-fabricated
γ-Fe2O3 SNTs are ferromagnetic, and its coercivity is nonzero when the temperature above blocking temperature (T
B). The hysteresis loop was operated to show that the magnetic properties of γ-Fe2O3 SNTs are strongly influenced by the morphology of the crystal. The unique magnetic behaviors were interpreted by the competition
of the demagnetization energy of quasi-one-dimensional nanostructures and the magnetocrystalline anisotropy energy of particles
in SNTs. 相似文献
726.
LS Tam EK Li CB Leung KC Wong FM Lai A Wang CC Szeto SF Lui 《Canadian Metallurgical Quarterly》1998,91(8):573-580
We evaluated the efficacy and safety of long-term treatment with cyclosporin A (CSA) in type IV lupus nephritis. Seventeen patients with biopsy-proven WHO type IV lupus nephritis were enrolled in a prospective, open study. Twelve of the 17 completed 48 months of treatment with CSA and prednisolone. Three patients required the addition of azathioprine, at 12, 38 and 47 months, respectively, for cutaneous disease flare with refractory rashes. One patient was lost to follow-up at 40 months. The mean +/- SD duration of treatment was 43.2 +/- 10.1 months (range 15.7-48 months). A significant reduction of proteinuria and a significant rise in serum albumin were noted 1 month after initiation of treatment. Improvement was maintained throughout the study except for three patients who relapsed with recurrence of nephrotic syndrome. There were no significant changes in serum creatinine level or creatinine clearances throughout the study. Repeat renal biopsy at 12 months following treatment with CSA showed histological improvement, with WHO type II changes in all 17 patients accompanying significant reduction in activity indices. Patients with baseline haemoglobin (Hgb) levels < 12 g/dl showed significant improvement. Serum C3 and C4 levels were not changed significantly. Corticosteroid-sparing effects were noted. Side-effects included hypertension, gum hypertrophy and mild hirsuitism, but were not serious. Combination therapy using CSA and prednisone is effective and safe for long-term treatment in lupus patients with WHO type IV nephritis. 相似文献
727.
Female rats were fed a purified ration containing 20% fat during gestation and lactation and the offspring were fed a commercial ration after weaning. The fat content of the purified ration was butter oil, a mixture of equal parts of butter oil and lard, or safflower oil. Brains of the dams were analyzed 1 month after parturition and brains of the offspring were analyzed when they were 20 weeks of age. Brains of the dams and offspring fed the safflower oil (about 75% linoleic acid) exhibited changes if comparisons were made with those fed other fats. In the dams, the percentage of cerebral weight as related to total brain weight was increased and the dry weight percentages of the cerebrum and brainstem were increased. In the cerebrums of male and female offspring, the DNA concentrations were increased and the RNA:DNA ration were decreased. 相似文献
728.
729.
LA Mitchell GD Jackson RM Kalnins MM Saling GJ Fitt RD Ashpole SF Berkovic 《Canadian Metallurgical Quarterly》1999,52(2):327-336
OBJECTIVE: To examine the nature and frequency of anterior temporal lobe (AT) abnormalities that occur in intractable temporal lobe epilepsy (TLE). METHODS: We reviewed the MR scans and clinical histories of 50 consecutive patients with intractable TLE. Histopathology was available in 42 surgically treated cases. RESULTS: MRI demonstrated loss of the gray-white matter differentiation and decreased T1- and increased T2-weighted signal in the ipsilateral AT in 58% of the 50 patients. This appearance was observed in 64% of the 36 patients with hippocampal sclerosis (HS) but was also seen in patients without HS. These changes were associated with temporal lobe atrophy, a higher hippocampal T2 relaxation time, and a history of febrile convulsions. Pathologic examination showed that the MRI appearances were not caused by dysplasia, degenerative abnormalities, or inflammatory change. Histologic quantitation showed increased glial cell nuclei counts in the intractable TLE cases compared with controls. There was no difference in glial cell numbers between cases with AT abnormality and those without this appearance. Presence or absence of changes was not predictive of preoperative neuropsychology, postoperative change in neuropsychology, or seizure outcome after surgery. CONCLUSIONS: These frequently seen ipsilateral changes are not caused by gliosis and may reflect a nonspecific increase in water content in the temporal lobe. This may be due to myelin abnormalities or some other as yet unidentified pathologic factor. 相似文献
730.
The feasibility of combining nonaqueous capillary zone electrophoresis with indirect fluorescence detection was studied for the efficient separation and sensitive detection of ionizable hydrophobic substances which do not possess practically suitable detection properties. Medium- and long-chain free fatty acids, C6-C24, were selected as test compounds. The results showed that such a wide range of medium- and long-chain free fatty acids could be separated between any two consecutive homologs in one run and be detected at a level of about 0.01-0.02 mM in highly basic methanol/acetonitrile media containing fluorescein as coion of background electrolyte for indirect fluorescence detection. 相似文献