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991.
No abstract. Copyright 1998 The Association for the Study of Animal Behaviour.  相似文献   
992.
OBJECTIVE: To determine whether, in individuals in the general population with hand symptoms, there is a greater level of disability in those with objective evidence of delayed nerve conduction. METHODS: A 19 item disability schedule relevant to hand function was developed for this survey. Subjects included 71 individual respondents to a random population survey who reported pain, tingling, numbness, or loss of sensation in the hands during an interview and who agreed to have nerve conduction studies. They were divided into those with (10) and without (61) delayed median nerve conduction. RESULTS: Those with delayed conduction were more likely to report disability for 14 of the 19 items assessed. Half those with delayed conduction reported disability in 7 or more items, compared with 18% of those with normal conduction (chi-squared = 7.49, p = 0.006). Disability items that showed the greatest disparity between the 2 groups were those that relied on hand, although not specifically fine hand, movements. CONCLUSION: Individuals with hand symptoms in the general population who have objective evidence of delayed nerve conduction have a greater degree of self-reported disability than those with normal conduction.  相似文献   
993.
The sol-gel process was used to produce zirconia powders that were pressed into compacts. The powders were synthesized from zirconium n-propoxide, diluted in propanol, and hydrolyzed with molar ratios of water either l-to-l or lo-to-l. Zirconia compacts produced in this manner were soaked in 1N NaOH to simulate a membrane cleaning process, and their weight loss was recorded. Zirconia samples with a higher weight fraction of tetragonal phase exhibited less weight loss than samples with more monoclinic phase. The weight fraction of the tetragonal phase was controlled by synthesis conditions and tiring temperature.  相似文献   
994.
This paper reports that lesions of the medial frontal cortex (MFC) caused behavioral deficit in rats and that this deficit could be attenuated by a well formulated treatment with Org2766, an analog of ACTH-(4-9). Wistar rats were distributed in 3 groups: MFC lesion treated with saline (M-N); MFC lesion treated with Org2766 (M-O); and sham-operation treated with saline (S). Repeated Org2766 or saline injection commenced from the day of surgery and lasted for 13 days. After surgery, the rats were trained in a passive avoidance task and then in an active avoidance task. MFC lesions were found to be strongly associated with behavioral deficits. The M-N group rats displayed poor retention of the passive avoidance response and showed much slower learning of the active avoidance task as compared to S group rats. The result showed that chronic Org2766 administration improved the behavioral performance of both tasks in MFC lesioned rats. The also revealed that the superoxide dismutase (SOD) activity was significantly increased in the M-O group as compared to the M-N group 15 days after surgery. The possible mechanisms related to the beneficial effect of Org2766 on cortex damage are discussed.  相似文献   
995.
According to this review, religion plays a largely positive role in mental health; future research on severe mental disorders should include religious factors more directly.  相似文献   
996.
The effects of acute challenge with ethanol were studied in a putative rodent model of tardive dyskinesia. Chronic administration of fluphenazine elicited vacuous chewing movements (VCMs) in the rat. Neuroleptic-induced VCMs were dose dependently suppressed by ethanol in a behaviorally specific fashion. Suppression by ethanol of neuroleptic-induced VCMs was reversed by pretreatment with the benzodiazepine inverse agonist Ro 15-4513 (2.5 mg/kg). These findings suggest that ethanol may acutely suppress neuroleptic-induced dyskinesias in humans via stimulation of GABAA receptors and are compatible with the previously reported clinical effects of alcohol consumption on the extrapyramidal system. Treatment strategies focussed on GABAergic stimulation deserve further investigation in the management of tardive dyskinesia.  相似文献   
997.
OBJECTIVE: To identify and determine trends in the prevalence of hepatitis C virus (HCV) antibody in stored sera from 1971 to 1975 and to determine associations with HCV seropositivity, including markers for other hepatitis infections and possible routes of transmission. DESIGN: A retrospective cross-sectional study. PATIENTS AND SETTING: 1511 adults admitted to Fairfield Infectious Diseases Hospital, Victoria, with a clinical and biochemical diagnosis of hepatitis between 1 January 1971 and 31 December 1975. MAIN OUTCOME MEASURES: Prevalence over study period of hepatitis A virus antibody (anti-HAV) IgM, hepatitis B core antibody (anti-HBc), hepatitis B surface antigen (HBsAg) and hepatitis C virus antibody (anti-HCV) in stored sera; sociodemographic data and risk factors for blood-borne viruses documented in original medical records. RESULTS: Anti-HCV was detected in 17% of adults admitted with hepatitis from 1971 through 1975. Prevalence increased significantly over this period. Most cases were in young men who had a history of injecting drug use. HCV seropositivity was also significantly associated with markers for hepatitis B infection. CONCLUSIONS: Given the 20-30-year period between infection with hepatitis and the development of liver disease, our findings predict significant liver-related morbidity in Australia in the next decade. The increase in prevalence over the five years studied suggests rapid spread of HCV through susceptible populations, principally injecting drug users.  相似文献   
998.
During pregnancy, mouse uterine epithelial cells produce and secrete a large amount of macrophage colony-stimulating factor (M-CSF/CSF-1). Macrophages accumulate and proliferate in the undecidualized endometrium of the pregnant uterus. Observations showed that macrophages expressed scavenger receptor class A (type I and type II) and class C (macrosialin). Scavenger receptors appeared to be involved in the removal of apoptotic cells in the degenerated decidual tissue. The expression of class A and class C scavenger receptor mRNAs in the uterus of pregnant mice was elevated but the expression of class B scavenger receptor (CD36) mRNA was similar to that of non-pregnant mice. The expression of various cytokines and chemokines, including M-CSF, monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein 1-alpha (MIP1-alpha), was enhanced in the uterus of pregnant mice, suggesting that these molecules regulate macrophage chemotaxis and immunological function in the uterus. These findings imply that the pregnant uterus provides a microenvironment for the recruitment, differentiation, and proliferation of macrophages and the regulation of scavenger receptor and cytokine expression for a successful pregnancy.  相似文献   
999.
1000.
Previous studies from our laboratory, using p53 transgenic mice, have suggested that ultraviolet (UV) light-induced keratinocyte apoptosis in the skin is not affected by overexpression of mutant p53 protein. To further elucidate a possible role for p53 in UV-induced keratinocyte cell death, we now examine apoptosis in skin and isolated keratinocytes from p53 null (-/-) mice and assess the influence of cell differentiation on this process. In vivo, using this knockout model, epidermal keratinocytes in p53-/- mice exhibited only a 5.2-fold increase in apoptosis after 2000 J/m2 UVB irradiation compared with a 26.3-fold increase in normal control animals. If this p53-dependent apoptosis is important in elimination of precancerous, UV-damaged keratinocytes, then it should be active in the undifferentiated cells of the epidermal basal layer. To test this hypothesis, we examined the effect of differentiation on UV-induced apoptosis in primary cultures of murine and human keratinocytes. Apoptosis was p53-independent in undifferentiated murine keratinocytes, which exhibited relative resistance to UVB-induced killing with only a 1.5-fold increase in apoptosis in p53+/+ cells and a 1.4-fold increase in p53-/- cells. Differentiated keratinocytes, in contrast, showed a 9.4-fold UVB induction of apoptosis in p53+/+ cells, almost three times the induction observed in p53-/- cells. This UV-induced difference in apoptosis was observed when keratinocytes were cultured on type IV collagen substrate, but not on plastic alone. Western blotting of UV-irradiated, differentiated keratinocytes did not support a role for either Bax or Bcl-2 in this process. In support of these findings in mice, cell death in human cultured keratinocytes also occurred in a differentiation-associated fashion. We conclude that p53-induced apoptosis eliminates damaged keratinocytes in the differentiated cell compartment, but this mechanism is not active in the basal, undifferentiated cells and is therefore of questionable significance in protection against skin cancer induction.  相似文献   
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