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181.
In a prospective study at a single centre between August 1995 and March 1996, 193 patients with elbow injuries were studied. Standard radiographs of the elbows were taken. A total of 181 X-rays were reported by one person concerning the presence or absence of fractures and fat-pad signs. The radiographs were analysed and positive predictive values were calculated for the presence of the fat-pad sign with radial head/neck fractures. The sensitivity for radial head/neck fracture is 85.4 per cent, while the specificity is only 50 per cent. The fat-pad sign must be used cautiously as an indicator of radial head/neck fractures; its absence is a more reliable indicator of the absence of a radial head/ neck fracture.  相似文献   
182.
Organic solvent inhalation is a serious problem among youths in Japan. It induces physical and mental disorders, and is related closely to crime and delinquency. The relationship between solvent inhalation and antisocial behavior was investigated in 75 youths. The subjects were divided into three groups according to the level of violent behavior and the time of appearance: a non-violent group, a late-onset group (violence occurred after the start of inhalation) and an early-onset group (violence had occurred before the start of inhalation). Various parameters were compared among the groups. The late-onset group showed the following characteristics; (i) the frequency of inhalation was high, and many subjects experienced hallucinations and mood changes caused by inhalation; (ii) the family environment was characterized by conflict; and (iii) the subjects had strong psychological conflicts and showed dissociative coping with frustration. The violence, psychological conflict and dissociation in this group were found to be related to the inhalation, with familial conflict as a background. The violence in the early-onset group was considered to be the manifestation of a violent personality as the frequency of inhalation and the incidence of mental symptoms were both low. The subjects in this group showed weak psychological conflict and tended to be demanding of others when attempting to cope with frustration. Two types of violent behaviors in the teenagers who inhaled solvents were identified. The violence of solvent inhalers should be managed according to the type.  相似文献   
183.
Vinylidenebisphosphonic acid tetraethyl ester (1) and diazo ketones 7a-1 in ether at 22 degrees C yield pyrazoline bisphosphonate tetraethyl esters 8a-1 in moderate to good yield. These compounds were evaluated in animal models of arthritis: rat adjuvant-induced polyarthritis (AIP) and murine antigen-induced arthritis (AIA) and a murine model of chronic inflammation, the delayed type hypersensitivity granuloma reaction (DTH-GRA). (5-Benzoyl-2,4-dihydro-3H-pyrazol-3-ylidene)-bisphosphonic acid tetraethyl ester (8a), and [5-(3-fluorobenzoyl)-2,4-dihydro-3H-pyraxol-3-ylidene]- bisphosphonic acid tetraethyl ester (8d) significantly inhibited the arthritis models, AIP (15 mg/kg) and AIA (25 mg/kg), as well as the DTH-GRA (25 mg/kg). Conversion of 8a to the corresponding bisphosphonic acid, 10a, resulted in loss of activity. Compounds with alkyl substituents on the pyrazoline nitrogen, 9a-d, were inactive in the DTH-GRA. These results show that 8a and 8d have novel antiinflammatory activity and are capable of inhibiting chronic arthritis and inflammation in animals. Such compounds might be useful in man for treating chronic tissue injury associated with arthropathies such as inflammatory joint disease as well as other chronic inflammatory diseases.  相似文献   
184.
Anaemia is a commonly encountered medical condition, although associated ophthalmic manifestations are not often sought or recognised. The authors present a case report of a patient with severe vitamin B12 deficiency anaemia with florid retinal changes classical of anaemic retinopathy. A review of the ocular involvement in anaemia is also presented.  相似文献   
185.
PURPOSE: To quantify the workload of residents on night call and to determine the residents' perceptions of the balance between service and education in their night-call activities. METHOD: Twenty-two internal medicine residents--nine first-year residents and 13 senior residents (i.e., in their second, third, or fourth year)--kept logs of their night-call activities for two periods of 16 days each in 1991-92, at a 772-bed teaching hospital affiliated with Wright State University School of Medicine. The residents used the following five-point scale to rate each activity: 1, strictly service; 3, even balance; 5, strictly education. They also recorded the total times spent on various activities. Data were analyzed by using the independent and paired t-tests. RESULTS: Ninety-eight percent of the logs were returned. The first-year and senior residents did not differ significantly in times spent on logged events. Both the first-year and the senior residents perceived many night-call activities to be weighted toward education, especially those involving evaluation of acutely ill patients being considered for hospital admission (overall mean rating of 3.3). There was no striking difference between the first-year and senior residents' perceptions of the balance between service and education in their activities. CONCLUSION: The residents' perceptions of the relationship between service and education indicate that there was an even balance between the two. The educational aspects of night-call duties can and should remain an integral part of residents' training.  相似文献   
186.
Neu (c-erbB2) is a proto-oncogene product that encodes an epidermal growth factor-like receptor tyrosine kinase. Amplification of wild-type c-Neu and mutational activation of Neu (Neu T) have been implicated in oncogenic transformation of cultured fibroblasts and mammary tumorigenesis in vivo. Here, we examine the relationship between Neu tyrosine kinase activity and caveolin-1 protein expression in vitro and in vivo. Recent studies have suggested that caveolins may function as negative regulators of signal transduction. Our current results show that mutational activation of c-Neu down-regulates caveolin-1 protein expression, but not caveolin-2, in cultured NIH 3T3 and Rat 1 cells. Conversely, recombinant overexpression of caveolin-1 blocks Neu-mediated signal transduction in vivo. These results suggest a reciprocal relationship between c-Neu tyrosine kinase activity and caveolin-1 protein expression. We next analyzed a variety of caveolin-1 deletion mutants to map this caveolin-1-dependent inhibitory activity to a given region of the caveolin-1 molecule. Results from this mutational analysis show that this functional in vivo inhibitory activity is contained within caveolin-1 residues 32-95. In accordance with these in vivo studies, a 20-amino acid peptide derived from this region (the caveolin-1 scaffolding domain) was sufficient to inhibit Neu autophosphorylation in an in vitro kinase assay. To further confirm or refute the relevance of our findings in vivo, we next examined the expression levels of caveolin-1 in mammary tumors derived from c-Neu transgenic mice. Our results indicate that dramatic reduction of caveolin-1 expression occurs in mammary tumors derived from c-Neu-expressing transgenic mice and other transgenic mice expressing downstream effectors of Neu-mediated signal transduction, such as Src and Ras. Taken together, our data suggest that a novel form of reciprocal negative regulation exists between c-Neu and caveolin-1.  相似文献   
187.
OBJECTIVE: To determine whether implantable insulin pump (IIP) and multiple-dose insulin (MDI) therapy have different effects on cardiovascular risk factors in insulin-requiring patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: A randomized clinical trial was conducted at seven Veterans Affairs medical centers in 121 male patients with type 2 diabetes between the ages of 40 and 69 years receiving at least one injection of insulin per day and with HbA1c, levels of > or =8% at baseline. Weights, blood pressures, insulin use, and glucose monitoring data were obtained at each visit. Lipid levels were obtained at 0, 4, 8, and 12 months, and free and total insulin levels were obtained at 0, 6, and 12 months. All medications being taken were recorded at each visit. RESULTS: No difference in absolute blood pressure, neither systolic nor diastolic, was seen between patients receiving MDI or IIP therapy, but significantly more MDI patients required anti-hypertensive medications. When blood pressure was modeled against weight and time, IIP therapy was significantly better than MDI therapy for systolic blood pressure in patients with BMI <33 and for diastolic blood pressure in patients with BMI >34 kg/m2. Total cholesterol levels decreased in the overall sample, but IIP patients exhibited significantly higher levels than MDI patients. Triglyceride levels increased over time for both groups, with IIP patients having significantly higher levels than patients in the MDI group. BMI was a significant predictor of, and inversely proportional to, HDL cholesterol level. No difference in lipid-lowering drug therapy was seen between the two groups. Free insulin and insulin antibodies tended to decrease in the IIP group as compared with the MDI group. C-peptide levels decreased in both groups. CONCLUSIONS: IIP therapy in insulin-requiring patients with type 2 diabetes has advantages over MDI therapy in decreasing the requirement for antihypertensive therapy and for decreasing total and free insulin and insulin antibodies. Both therapies reduce total cholesterol and C-peptide levels.  相似文献   
188.
We conducted a study of the association between developmental reading disability (DRD) and immune disorders (ID) using both survey and immunoassay data in two separate samples of families. One sample was made up of twins and their parents and was ascertained through a population-based sampling scheme. The other sample was a set of extended pedigrees selected for apparent autosomal dominant transmission of DRD. We failed to find an association between DRD and ID in either sample, regardless of the method used to assess immune system function. Even though our twin sample provided evidence that both DRD and immune conditions were significantly heritable, there was no evidence for a genetic correlation between ID and DRD nor was there any clear indication that a special subgroup of individuals may be comorbid for these conditions because of genetic reasons. How these negative findings can be reconciled with the developmental hypothesis of Geschwind, Behan, Galaburda, and colleagues, and how they may relate to the gene locus influencing DRD that has been recently located in the HLA region of the short arm of chromosome 6 is discussed.  相似文献   
189.
This study examined the changes of beta-adrenoceptors in the guinea-pig sinoatrial nodal region following 7 day (-)-isoprenaline (400 micrograms/kg/h s.c.) infusion and the relationship between beta-adrenoceptor desensitization and receptor down-regulation. Changes in beta 1- and beta 2-adrenoceptor density were measured using quantitative autoradiography and function in organ bath studies. (-)-Isoprenaline treatment produced a marked decrease in total (from 57.5 to 33.9 fmol/mg protein), beta 1- (from 49.4 to 32.8 fmol/mg protein), and beta 2-adrenoceptor density (from 8.1 to 1.05 fmol/mg protein) in the sinoatrial node. In adjacent right atrium, treatment produced no change in total (39.5 and 36.7 fmol/mg protein) or beta 1-adrenoceptors (35.9 and 36.4 fmol/mg protein) but did decrease beta 2-adrenoceptors (from 3.7 to 0.3 fmol/mg protein). Chronotropic effects were measured in spontaneously beating right atrium. Procaterol, a selective beta 2-adrenoceptor agonist, caused a biphasic chronotropic response in control right atria, the first part of which was abolished in the tissue from treated animals. The maximum increase in right atrial rate to RO363, a beta 1-adrenoceptor selective partial agonist, was reduced from 114 bpm in control to 43 bpm in treated animals. In electrically driven right atrium with the sinoatrial node removed procaterol failed to produce a positive inotropic response via beta 2-adrenoceptors, but the maximum response to RO363 was reduced from 0.75 g in the control tissue to 0.12 g in the treated tissue. This study showed that changes in beta 2-adrenoceptor density following 7 day (-)-isoprenaline infusion are compatible with reduced functional responsiveness in the SA node. The reduction of beta 1-adrenoceptor number in the SA node was also compatible with the reduced chronotropic response in this tissue. However the lack of effect on beta 1-adrenoceptor density in the right atrium was not consistent with the decrease in beta 1-adrenoceptor mediated inotropic response in this tissue. This suggests that beta-adrenoceptor desensitization is not always associated with receptor down-regulation but depends also on the changes in the cell signalling system beyond the level of the receptor which differ according to the cardiac location.  相似文献   
190.
Stimulation of alpha-adrenoceptors on ventricular cardiomyocytes isolated from adult rat hearts leads to cellular alkalization, increases of creatine phosphate concentration, RNA mass, and protein synthesis. This study investigated whether the increase of creatine phosphate concentrations is causally linked to the hypertrophic response of cardiomyocytes under alpha-adrenoceptor stimulation. Cellular alkalization achieved with phenylephrine (10 microM), an alpha-adrenoceptor agonist, was abolished in the presence of the sodium-proton-exchange (NHE)-inhibitor HOE 694 (1 microM). HOE 694 inhibited also the alpha-adrenoceptor-mediated increase in cellular creatine phosphate and the increase in cellular RNA mass. The phenylephrine-induced stimulation of protein synthesis (determined by incorporation of 14C-phenylalanine) was reduced by one-third when HOE 694 was present. beta-Guanidinopropionic acid was added to cardiomyocytes to reduce cellular creatine phosphate concentrations. In these cultures, alpha-adrenoceptor stimulation activated NHE, but creatine phosphate concentrations were not increased. Protein synthesis was augmented to the same extent as in control cultures, but total RNA mass did not increase. From these results we conclude that alpha-adrenoceptor stimulation causes the increase in protein synthesis via activation of NHE, but independent of the concomitant increase in creatine phosphate contents. The effect of alpha-adrenoceptor stimulation on total RNA mass (translational capacity) is also caused by NHE activation, but depends on the changes in creatine phosphate contents as well.  相似文献   
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