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881.
SE Kirkpatrick PT Pitlick MJ Hirschklau WF Friedman 《Canadian Metallurgical Quarterly》1976,126(8):1034-1037
In adult animals and man, both acute and chronic ethanol intake is associated with depression of myocardial performance. Accordingly, the cardiac effects of maternal ethanol infusions, in a manner comparable to common obstetric practice of inhibition of premature labor with ethano mighte for inhibition of premature labor, were evaluated in six chronically instrumented fetal sheep. Fetal and ewe arterial PO2, PCO2, and pH values remained within normal limits with infusion rates of 15 c.c. per kilogram of 10 per cent ethanol over two hours (blood ethanol = 110 mg. per cent) and 15 c.c. per kilogram over one hour (blood ethanol = 210 mg. per cent). Fetal instrument evaluation (for 14 to 30 days after operation) provided data concerning pressures and cardiac dimensions which allowed analysis of left ventricular performance. Ethanol produced a significant depression of the extent (p less than 0.01) and velocity (p less than 0.001) of left ventricular myocardial fiber shortening as well as in the mean rate of left ventricular myocardial fiber shortening as well as in the mean rate of left ventricular circumferential fiber shortening (p less than 0.01). These indices of cardiac contractility were depressed in the absence of changes in end diastolic diameter, left atrial pressure, and systemic arterial pressure. Thus, the practice of inhibition of premature labor with ethano6 might contribute to depressed myocardial performance in the neonatal period. 相似文献
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OBJECTIVE: To investigate trends in the incidence of giant cell arteritis over a 42-year period in Olmsted County, Minnesota. DESIGN: Population-based incidence study. SETTING: Olmsted County, Minnesota. METHODS: All incidence cases of giant cell arteritis first diagnosed between 1950 and 1991 were identified using the unified record system at Mayo Clinic. Age- and sex-specific incidence rates were calculated using the number of incidence cases as the numerator and population estimates as the denominator. Overall rates were age- and sex-adjusted to the 1980 United States white population. The annual incidence rates were graphically illustrated using a 3-year centered moving average. RESULTS: Between 1950 and 1991, 125 Olmsted County residents (103 women and 22 men) were diagnosed with giant cell arteritis. The age- and sex-adjusted incidence per 100,000 persons 50 years of age or older was 17.8 (95% CI, 14.7 to 21.0); incidence was significantly higher in women (24.2 [CI, 19.5 to 28.9]) than in men (8.2 [CI, 4.8 to 11.6]). Age-specific incidence rates increased with age (P < 0.0001). The annual incidence rates increased significantly over the study period (P = 0.002) and appear to have clustered in five peak periods, which occurred about every 7 years. A significant calendar-time effect was identified; it predicted an increase in incidence of 2.6% (CI, 0.9% to 4.3%) every 5 years. CONCLUSIONS: Our observation of a regular cyclic pattern in incidence rates over time supports the hypothesis of an infectious cause for giant cell arteritis. Similar studies in other populations are needed to confirm our findings. 相似文献
884.
A Bukovsky JA Keenan MR Caudle J Wimalasena NB Upadhyaya SE Van Meter 《Canadian Metallurgical Quarterly》1995,33(4):323-340
PROBLEM: Formation of primordial follicles in adult ovaries could be a cryptic process limited to relatively small areas of the ovarian cortex and occurring during a certain stage of the menstrual cycle. Such an event may require a specific milieu provided by factors involved in developmental processes, i.e., morphoregulatory molecules and macrophages. METHOD: Adult human ovaries were investigated by immunohistochemistry for surface epithelium and granulosa cell markers (cytokeratin 18 and MHC class I), immune system-related morphoregulatory molecules (Thy-1 glycoprotein and N-CAM), and macrophage phenotypes (CD14, CD68, and MHC class II). RESULTS: In some ovaries 300-500 microns areas of surface epithelium were overgrown by tunica albuginea, descended into the stroma, and apparently fragmented into individual small (20-40 microns) follicle-like cell nests. Differentiation of the surface epithelium was accompanied by macrophages and Thy-1 glycoprotein. Small segments of surface epithelium showed N-CAM and a lacked MHC class I expression. In such segments, clear spherical germ-like cells migrated into the deeper stroma, associated with the microvasculature, and eventually aggregated with follicle-like cell nests. CONCLUSIONS: Our data suggest that surface epithelium may be involved in the formation of some primordial follicles in adult ovaries. This process, and further follicular fate, may require a precise interplay of immune system related morphoregulatory molecules and macrophages. 相似文献
885.
SE Starkstein L Sabe S Vazquez A Teson G Petracca E Chemerinski G Di Lorenzo R Leiguarda 《Canadian Metallurgical Quarterly》1996,27(3):408-414
BACKGROUND AND PURPOSE: Psychiatric, neuropsychological, and cerebral blood flow differences between patients with ischemic vascular dementia (IVD) or Alzheimer's disease (AD) were examined. METHODS: A consecutive series of patients who met either the criteria of the National Institute of Neurological Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association for probable AD or the State of California AD Diagnostic and Treatment Centers criteria for probable IVD were included in the study. Twenty consecutive patients with IVD were matched for age, sex, and Mini-Mental State Examination scores with 40 consecutive patients with probable AD. Patients underwent a psychiatric interview, a neuropsychological assessment, and single-photon emission CT imaging with 99mTc-hexamethylpropyleneamine oxime. RESULTS: Patients with IVD showed significantly more severe anosognosia (P<.05) and emotional lability (P<.01) than AD patients, but no significant between-group differences were found in the frequency and severity of depression. IVD patients showed significantly more severe deficits in tests of planning, sequencing (P<.05), and verbal fluency (P<.05) as well as significantly more severe cerebral blood flow deficits in the basal ganglia (P<.01) and the frontal lobes (P<.001) than AD patients. CONCLUSIONS: Patients with IVD showed a relatively more severe dysfunction of the frontal lobes as demonstrated by single-photon emission CT and expressed in specific psychiatric and neuropsychological changes than AD patients matched for age, sex, and severity of dementia. 相似文献
886.
AV Moses SE Williams JG Strussenberg ML Heneveld RA Ruhl AC Bakke GC Bagby JA Nelson 《Canadian Metallurgical Quarterly》1997,3(11):1242-1249
Human immunodeficiency virus (HIV)-1 infection is associated with the development of aggressive extranodal B-cell non-Hodgkin's lymphomas. Using microvascular endothelial cell (MVEC)-enriched bone marrow stromal cultures, HIV infection of stromal MVECs from lymphoma patients induced the outgrowth of malignant B cells. MVECs were the only HIV-infected cells in the stroma, and purified brain MVECs also induced a phenotype supportive of neoplastic B-cell attachment and proliferation. HIV infection of MVECs stimulated surface expression of CD40 and allowed preferential induction of the vascular cell adhesion molecule VCAM-1 after CD40 triggering. B-lymphoma cells expressed the CD40 ligand (CD40L), and blocking of CD40-CD40L interactions between HIV-infected MVECs and B-lymphoma cells inhibited B-cell attachment and proliferation. These observations suggest that HIV promotes B-lymphoma cell growth through facilitating attachment of lymphoma cells to HIV-infected MVECs and represent a novel mechanism through which viruses may induce malignancies. 相似文献
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