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991.
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994.
In a 81-year-old woman, who for many years had been treated with iron and vitamin B12 injections because of a 'tendency to anaemia', congenital haemolytic anaemia on the basis of glucose-6-phosphate dehydrogenase (G6PD) deficiency was diagnosed. The iron and vitamin medication was discontinued and after a blood transfusion because of signs of heart failure, the patient could leave the hospital in good condition. After instruction with regard to provocative factors, like eating of broad beans, no more haemolytic events occurred. Of her children and grandchildren, 2 sons and 1 granddaughter were G6PD deficient.  相似文献   
995.
OBJECTIVE: To assess dynamic Gd-DTPA-enhanced magnetic resonance (MR) imaging in the diagnosis of primary breast pathology, and to test the hypothesis that analysis of contrast agent kinetics increases specificity. METHODS: Forty-seven women underwent breast MR imaging using three-dimensional and dynamic spoiled gradient-recalled sequences. Image interpretation was based on the evaluation of lesion conspicuity, signal intensity, contour and enhancement pattern from the static acquisitions. Assessment of contrast kinetics was based on pixel-by-pixel analysis of the dynamic data. A two-compartment model described by three parameters (amplitude of uptake, exchange rate and washout rate), and a three-compartment model described by two parameters (permeability and exchange rate) were used. Regions of interest were drawn for all lesions found in the dynamic sections. Mean regional pixel values were calculated for each parameter and tested for diagnostic efficacy. RESULTS: Twenty-two malignant and 36 benign lesions were examined. Fibroadenomas accounted for 86% of the benign tumours. Image interpretation had a sensitivity of 0.95 and specificity of 0.86. The fat-suppressed post-contrast images permitted good visualization of the contour and matrix characteristics of fibroadenomas, but all non-fibroadenomatous benign lesions were classified as indeterminate or suspicious. Significant differences were found between benign and malignant lesions in the amplitude of uptake (P = 0.0008) and exchange rate (P < 0.00005) of the two-compartment model, and permeability (P=0.0001) and exchange rate (P < 0.00005) of the three-compartment model. However, image interpretation was superior to the isolated use of quantitative indices (P=0.02). The most discriminating parameters were the exchange rates of both models, with no significant difference between them. CONCLUSION: Assessment of lesion morphology is essential and probably sufficient for the differentiation of fibroadenomas from malignant tumours. However, specificity of conventional MR imaging may be much lower for other types of primary benign breast pathology. Analysis of Gd-DTPA kinetics improves the specificity obtained using simple enhancement measurements and can be used to produce parametric images that provide information about lesion heterogeneity, permeability and vascularity.  相似文献   
996.
The effect associated with the substitution of adenine (A) for guanidine (G) in the promoter region of the apolipoprotein AI gene (-75 bp) with plasma apo AI and high-density lipoprotein (HDL) levels was investigated in the European Atherosclerosis Research Study (EARS). This is a study of healthy offspring (cases) of fathers who had suffered premature myocardial infarction (MI) before age 55 years (n = 565) and age- and sex-matched controls (n = 1,078) from 12 European countries, divided into 5 regions based on geography and language. The frequency of the polymorphism was not significantly different among the regions and the relative frequency of the rare A allele was similar in cases and controls (0.159 vs. 0.142) combining data from all regions. Individuals with one or more A allele had significantly higher plasma apo AI levels (P < 0.05) than individuals homozygous for the G allele. This effect was consistent in all regions. The data were analyzed separately in males and females. In females, those with one or more A allele had significantly higher apo AI levels (P = 0.05) than individuals homozygous for the G allele, and this raising effect of the A allele was greater in cases than controls for both apo AI (5.23% vs. 1.56%) and HDL (4.48% vs. 1.89%). In males, the A allele was associated with higher levels of apo AI and HDL, but the effect was much smaller and the differences did not reach statistical significance. In the females, where the effect of the A allele was strongest, the effect on apo AI associated with genotype was evident in non-smokers, and individuals with one or two A alleles had 3.6% higher apo AI and 3.14% higher HDL levels than individuals homozygous for the G allele. However, in the female smokers the raising effect of the A allele was greatly reduced (0.56%). Thus genetic variation in the promoter region of the apo AI gene is associated with differences in apo AI and HDL levels in healthy individuals throughout Europe, but the effect is modulated by gender, environmental factors such as smoking, and a family history of MI.  相似文献   
997.
OBJECTIVE: To measure the prognostic utility of helper T-cell (CD4) counts in human immunodeficiency virus (HIV)-infected patients undergoing major abdominal surgery. DESIGN: Retrospective case series. SETTING: Three university-affiliated hospitals. PATIENTS: Forty-three HIV-infected patients undergoing major abdominal surgery. MAIN OUTCOME MEASURES: Morbidity and mortality rates with respect to CD4 cell counts. RESULTS: Nineteen of 32 patients who had CD4 cell counts less than 0.20 X 10(9)/L (200 cells/microL) suffered major complications compared with 2 of 11 patients who had CD4 cell counts greater than 0.20 x 10(9)/L (200 cells/microL) (P=.03). Perioperative mortality was 38% for patients with CD4 cell counts less than 0.20 x 10(9)/L, and was 9% for those with CD4 cell counts greater than 0.20 x 10(9)/L (P=.13). Six months postoperatively, mortality rates were 47% and 9%, respectively (P=.03). Of patients with septic processes perioperatively (n=12), mortality was 75%, and was 19% (P=.009) for those with nonseptic processes (n=31). Nine patients had HIV-related intra-abdominal pathologic conditions at laparotomy. Mortality was 56% perioperatively (P=.13) and 88% after 6 months (P=.001). Sixty-eight percent of patients who received blood product transfusions developed complications, whereas only 7% of those who did not receive transfusions developed complications (P<.001). Overall mortality and morbidity rates were 37% and 49%, respectively. Patients with morbidity had lower CD4 cell counts (median, 0.034 x 10(9)/L) than those without complications (median, 0.102 x 10(9)/L) (P=.02). Similarly, patients who died had lower CD4 cell counts (median, 0.031 x 10(9)/L vs 0.088 x 10(9)/L) (P=.05). CONCLUSIONS: Patients with acquired immunodeficiency syndrome-defining CD4 cell counts undergoing major abdominal surgery developed more complications and had poorer outcomes at 6-month follow-up compared with HIV-infected patients whose CD4 cell counts were greater than 0.20 x 10(9)/L (200 cells/microL). A perioperative septic process and HIV-related pathologic conditions seen at laparotomy are also associated with worse outcomes.  相似文献   
998.
We evaluated the effectiveness of current strategies for educating patients in routine clinical practice in three related studies. (1) A study of overall knowledge in 100 patients with rheumatoid arthritis (RA) and osteoarthritis (OA) showed knowledge of diagnosis and treatment effects were high (86% and 83% respectively) but only a minority (37%) were well informed about side effects. (2) Patients' detailed knowledge of drug therapy was assessed in 50 RA and OA patients. Between 56%-92% knew why drugs were given, their use and their likely effects. But many patients were unaware of the main adverse reactions and also how to avoid or limit them. (3) The relationship of patient education to overall disease management was evaluated in 89 RA patients with 5-10 years disease duration using validate guidelines for specialist care. Those patients who had been give inadequate education about drug therapy had a reduced level of overall care. Although education is considered important by patients, it is often inadequate, and this is associated with a less effective overall treatment.  相似文献   
999.
A trial to determine the usefulness of recombinant human erythropoietin (rhEpo) as a mobilizing cytokine for patients with previously treated relapsed malignancies was performed. An initial peripheral stem cell apheresis collection was conducted during steady-state hematopoiesis for each patient to provide baseline data. rhEpo, 200 U/kg/day, was administered subcutaneously until the last apheresis procedure was completed. Immediately after the fourth daily dose of Epo, apheresis procedures were resumed and continued beyond five collections, when necessary, to accrue a total of 6.5 x 10(8) mononuclear cells (MNCs)/kg. Eight female and four male patients (median age = 44 years) were evaluated. Five to 14 (median = 8) apheresis procedures were performed for each patient. Toxicity attributable to Epo administration was negligible. Mobilization effects, as determined by an increase in the number of colony-forming units granulocyte/macrophage (CFU-GM) and burst-forming units-erythroid (BFU-E) in the apheresis products after Epo administration, were observed in all patients. Nine patients received high-dose chemotherapy and Epo-mobilized peripheral stem cell transplantation (PSCT). Beginning the day of the transplant, GM-CSF was administered until neutrophil recovery was satisfactory. The median time to recover 0.5 x 10(9)/L granulocytes was 16 days after PSCT. Epo appears to have mobilization properties. Further studies are needed to determine the clinical usefulness of Epo as a mobilizing cytokine. The addition of Epo to other mobilizing cytokines may provide increased effectiveness without adding toxicity.  相似文献   
1000.
BACKGROUND: Activation of platelets and expression of adhesion molecules (e.g. CD62P and CD63) which mediate interactions between platelets and other cells may be important in the pathogenesis of aspirin-sensitive asthma. OBJECTIVE: To determine the expression of CD62P and CD63 on platelets from aspirin-sensitive asthmatic (ASA+), aspirin-tolerant asthmatic (ASA-) and normal subjects and to assess the modulatory effect of aspirin on platelet CD62P and CD63 expression following stimulation with either platelet-activating factor (PAF), arachidonic acid (AA) or collagen (COL). METHODS: Platelet-rich plasma was obtained from 10 ASA+, 10 ASA- and 10 normal control subjects, and expression of CD62P and CD63 was measured by flow cytometry. Platelets were stimulated with PAF (10, 80 nM), AA (0.1, 1 mM) or COL (80, 800 micrograms/mL) with or without aspirin (concentration range 0.4-4 mg/mL). RESULTS: In the absence of aspirin, CD62P expression induced by AA and COL was greater in ASA+ patients compared with control subjects (P < 0.001) while CD62P expression with PAF, AA and COL was reduced in ASA- when compared with ASA+ and control subjects (P < 0.001). CD63 expression with PAF and AA was reduced in both ASA+ and ASA- patients compared with control subjects (P < 0.001). Aspirin inhibited the expression of both CD62P and CD63 after agonist stimulation. Greater inhibition of CD62P expression was observed in ASA+ compared with ASA- patients (P < 0.001) and normal subjects (P < 0.05) while greater inhibition of CD63 expression was observed in normal subjects compared with both ASA+ and ASA- patients (P < 0.05). In ASA+ patients and normal subjects, stimulation with PAF and COL resulted in only one platelet population while in contrast with 1 mM AA two populations were observed. CONCLUSIONS: Enhanced AA- and collagen-induced platelet CD62P expression in ASA+ patients compared with normal subjects and greater inhibition by aspirin of CD62P expression in ASA+ may be relevant to the pathogenesis of this syndrome. Reduced expression of CD62P and CD63 in platelets of ASA- patients following stimulation with PAF and AA may also have implications for the role of platelets and these mediators in the pathogenesis of other forms of asthma.  相似文献   
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