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21.
BACKGROUND/AIMS: Basal (BAO) and maximum (PAO) hydrochloric acid output after Histalog stimulation, basal pepsinogen (SPL-B), at 60 (SPL-60) and at 90 minutes (SPL-90), and basal gastrin (BG) levels were measured and compared in different gastric (GU) and duodenal (DU) ulcer sites. MATERIAL AND METHODS: Fifty nine patients with peptic ulcer were grouped according to Johnson's classification for gastric ulcers: type I (15), type II (16) type III (12) GU and (16) DU. Fifteen normal subjects were studied as controls. RESULTS: The BAO was greater in the DU than in the control or GU groups. No significant difference was noted in the production of hydrochloric acid after stimulation with Histalog. The SPL-B, at 60 and at 90 minutes was higher in type II GU than in the DU group and controls. The SPL-60 was higher in type II GU patients than in type III GU. Basal gastrin was higher in group DU and types II and III GU compared to the type I GU patients and controls. CONCLUSION: The topographic criteria for differentiating peptic ulcers has low discrimination capacity based on comparison of mean values of HCl acid production, pepsinogen and gastrin serum levels both basal and after stimulation with Histalog due to heterogeneity of these variables in group studies. In these studies, peptic ulcers from different sites should not be grouped as distinct entities except for type II gastric ulcers.  相似文献   
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Peripheral blood eosinophils from patients with eosinophilia and from healthy subjects were studied for surface immunoglobulins, receptors for the Fc region of IgG, complement receptors, and spontaneous rosette formation with sheep and mouse erythrocytes. Eosinophils were found to have receptors for complement and for aggregated IgG, and to have the same two types of complement receptors as do lymphocytes and monocytes. Immune adherence type receptors were specific for C4 or C3b, while C3d receptors were specific for C3d but unreactive with C4. Eosinophils differed from fully mature neutrophils in that the former had C3d receptors and relatively weak immune adherence (C4 or C3b) receptors, while the later did not have the C3d receptors and had strong immune adherence receptors. Eosinophil phagocytosis of complement-receptor bound erythrocytes was dependent on the presence of IgG in the antibody coating the red blood cells; this requirement for IgG resembled that found in neutrophil phagocytosis. No surface Ig or spontaneous erythrocyte rosette formation was observed with eosinophils.  相似文献   
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During January 1971--June 1975 we examined 195 patients with pancytopenia. The cause was bone marrow failure in 67.7% of cases (classic aplastic anaemia in 11.3%) hypersplenism in 7.7%, massive blood transfusions in 1.5%, severe infections in 9.7% (Gram-negative in 3%), and various other conditions in 7.8%. Records were insufficient for diagnosis in 5.6% of cases. Analysis of the 22 patients with aplastic anaemia showed no apparent aetiology in 16 (72.7%), previous phenylbutazone ingestion in 2, and Fanconi-type anaemia in 4 of 7 children. One-year survival was 73.7%, 2-year survival 71.4%, 3-year survival 63.6% and 4-year survival 57.1%. Marrow-investigation of the 21 available samples showed that 6 were acellular, 11 hypocellular and 4 normocellular. All patients received at least temporary therapy with anabolic steroids but its effectivity could not be satisfactorily assessed. Five patients died within 7 months and 5 patients went into remission, needing no further therapy. The initial haematological features of the 5 patients who died were not significantly different from those of the rest of the patients.  相似文献   
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The molarity of ethanol droplet and water drop penetration time methods are commonly used to determine soil wettability because these tests are quick and easy to perform. However, these tests do not provide reproducible results on the same sample. Low-field nuclear magnetic resonance (NMR) is shown as an alternative tool to determine soil wettability. Addition of small amounts of water in dry wettable porous media produces predominant amplitude peaks at transverse relaxation times (T2) of 100 ms or less while addition of water in dry water-repellent porous media with the same pore structure produce predominant amplitude peaks at T2 values near 1000 ms. The geometric mean of T2 (T(2gm)) from water-repellent samples immediately after the addition of water is greater than 1000 ms, which is close to that of bulk water, while T(2gm) from wettable samples immediately after the addition of water is significantly less than 1000 ms. Measurements over time show that water-repellent samples eventually reach the same equilibrium end point as its corresponding wettable sample when continually exposed to water. This paper will show that NMR can be used to formulate a screening criterion for quickly determining wettability. The advantage of using NMR is that the results are reproducible provided the sample is prepared and analyzed in a systematic manner.  相似文献   
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We studied the antibody binding capacity (ABC) of various cell-surface antigens in normal human fetuses and term neonates on lymphocyte, monocyte, and polymorphonuclear (PMN) cells by quantitative flow cytometry also designated by quantimetry. Analysis of changes of expression level on these leukocytes during the developmental process was also investigated. The results indicated that the ABC values of most studied markers change during the maturational process. The ABC of lymphocyte-associated antigens studied such as CD5 and CD7 showed only a decrease from fetus to adult, whereas according to the type of molecule on monocyte and PMN there was either an increase or a decrease of ABC values dependent on the stage of the developmental process, from fetus to neonate or from neonate to adult. However, the ABC values of leukocyte membrane antigens such as CD16, CD46, and CD55 on all leukocytes and CD11b, CD11c, and CD35 on myeloid cells did not change. Their expression level was already mature in fetuses compared with adult cells. In addition, in this quantimetric approach, the analysis of the results for CD11a and CD8 suggested that the changes of CD11a expression level on lymphocyte subsets can depend on one mechanism, whereas there are probably at least two for CD8. Furthermore, the expression patterns of CD5, CD7, and CD11a change during maturation. We concluded that, even if the neonate response pattern to immunological challenge differs from an adult and this is based primarily on the relative numbers and functional activity of lymphocyte T subsets (especially TH1/TH2) and their cytokine profiles, these quantitative and qualitative phenotypical differences might also contribute to explain the functional peculiarities of leukocyte fetal and cord blood cells. All these findings support the notion of immaturity and maturity of ABC expression.  相似文献   
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OBJECTIVE: There has been no reference material for T-lymphocyte subsets for normal children in developing countries. We therefore used T-lymphocyte subset determinations among children in three different studies in Guinea-Bissau to construct age-related reference material and to examine possible determinants of T-lymphocyte subset levels. METHODS: A total of 803 healthy West African children younger than 6 years were included in the three community studies of T-lymphocyte subsets among twins and singletons, after measles infection and after measles immunization. We used the immunoalkaline phosphatase method to determine T-lymphocyte subsets. RESULTS: We found differences by age, sex, and season, whereas there were no significant differences by birth order, twinning, or ethnic group. The CD4+ percentage declined from birth to age 2 years, at which time it started to increase to higher levels at age 4 to 5 years. The CD8+ percentage increased gradually from early infancy to age 2 to 4 years. The leukocyte count peaked at age 12 to 23 months and declined thereafter, whereas the lymphocyte percentage peaked at age 1 to 5 months and declined gradually thereafter. Compared with dry-season results, the lymphocyte percentage, the absolute lymphocyte count, the absolute CD4+ T-lymphocyte count, and the CD4+/CD8+ ratio were significantly lower during the rainy season, whereas the CD8+ percentage was increased during the rainy season. Girls had higher CD4+/CD8+ ratios and lower CD8+ percentages than did boys. CONCLUSIONS: Compared with the limited data on T-lymphocyte subsets available from healthy children in developed countries, Guinean children have markedly lower CD4+ percentages and CD4+/CD8+ ratios and higher lymphocyte percentages during the first 2 years of life, when the pressure of infections is particularly high in Africa.  相似文献   
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Current methods to assess voice outcomes in patients with unilateral vocal cord paralysis (UVCP) are limited by expense, reliability, or lack of a true patient-relevant focus. The purpose of this study was to develop and validate a patient-based, disease-specific instrument, the Voice Outcome Survey (VOS), that is brief, reliable, and sensitive to real clinical change in patients with UVCP. Fifty-six consecutive patients with uncompensated UVCP and without complicating comorbid illness received the VOS, the Medical Outcome Study Short Form 36-Item Health Survey (SF-36), and a voice laboratory analysis before and 6 months after type I thyroplasty. Overall, reliability of the VOS was excellent (r = 0.87, P < 0.0001). The VOS index was significantly (P < 0.05) correlated to subscales of the SF-36 including social functioning (SF) (r = 0.56) and physical role functioning (r = 0.35), as well as changes in objective voice measures such as phonation time (r = 0.51) and average intensity (r = 0.44). The VOS index was the most sensitive measure to clinical change after surgery (standardized response means: VOS, 1.92; phonation time, 0.68; SF, 0.58; physical role functioning, 0.53; intensity, 0.51). The VOS is a brief, valid, reliable, and highly sensitive measure of disease-specific health status in patients with UVCP.  相似文献   
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