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41.
K Kario T Nishikimi F Yoshihara S Takishita R Yamaoka T Matsuo H Matuso T Mitsuhashi K Shimada K Kangawa 《Canadian Metallurgical Quarterly》1998,16(9):1253-1259
OBJECTIVE: The aim of this study was to investigate the relationships between levels of natriuretic peptides and adrenomedullin and 24 h blood pressure levels in elderly hypertensives. DESIGN AND METHODS: We performed both 24 h ambulatory blood pressure monitoring and measurement of plasma levels of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and adrenomedullin in 118 asymptomatic hypertensive elderly (> 60 years old) patients. We classified the subjects into groups with isolated clinic hypertension (n = 40) and sustained hypertension (n = 78). We also measured the levels of these peptides in 37 elderly normotensive subjects. RESULTS: Plasma ANP and BNP levels were slightly increased in patients with isolated clinic hypertension compared with elderly normotensives. Among the hypertensives, plasma ANP and BNP levels were more closely related to 24 h blood pressure levels than to office blood pressure levels. Sustained hypertensives showed significantly increased plasma levels of ANP and BNP compared with isolated clinic hypertensives, while adrenomedullin levels were similar in the two groups. Elderly hypertensives with left ventricular hypertrophy detected by electrocardiography had significantly higher levels of ANP and BNP, and higher BNP/ANP ratios than those without left ventricular hypertrophy, while there was no significant difference in adrenomedullin levels between the two groups. CONCLUSIONS: Our results suggest that measurements of ANP and BNP may be useful in detecting left ventricular hypertrophy and in differentiating isolated clinic hypertension from sustained hypertension in elderly hypertensive patients. 相似文献
42.
Magnesium orthosilicate (forsterite) whiskers were synthesized by an oxidation-reduction reaction in the present investigation. These whiskers were rectangular parallelepipeds, with long sides in a cross-sectional view from two to ten times as long as the short sides, and measuring from several micrometers to 200 μm wide and ∼15 mm in the elongated direction. The Mg2 SiO4 elongation was on the c-axis. The growth mechanism of the whiskers was investigated on the basis of chemical thermodynamics, and the present study revealed that the Mg2 SiO4 whiskers grew by a VS (vapor-solid) mechanism . 相似文献
43.
K Yamaoka T Shigehisa K Ogoshi K Haruyama M Watanabe F Hayashi C Hayashi 《Canadian Metallurgical Quarterly》1998,7(6):535-544
In an attempt to examine differential effects of personality on health-related quality of life (HRQoL) without regard to disease type, we used the HRQoL-20, a general questionnaire (Japanese original scale) we developed (comprising 20 questions related to physiological, psychological or social HRQoL) and the Eysenck Personality Questionnaire (EPQ), which measures personality traits of extraversion (E), neuroticism (N) and psychoticism (P). The subjects (399 males and 429 females), stomach cancer patients, non-cancer patients (who had received acupuncture or moxibustion treatment) and healthy controls, were classified into three personality types. The results indicated that the HRQoL score of the tolerable/tolerant type (high E, low N and high P scorers) was greater than the intolerable/intolerant type (low E, high N and low P scorers) and also the unclassified type (neither of above scorers). The HRQoL correlated positively with the E and P scales and negatively with the N scale, in the case of all subjects, with the exception of N in male cancer patients and E in male non-cancer patients. The results supported the hypothesis that the HRQoL varies with personality variables, in that each patient, in different treatment settings, strives for the situation that is congruent with his/her personality to attain a better HRQoL. 相似文献
44.
WS Wang M Seki T Yamaoka T Seki S Tada T Katada H Fujimoto T Enomoto 《Canadian Metallurgical Quarterly》1998,1443(1-2):198-202
We cloned cDNAs encoding mouse homologues for the human DNA helicase Q1/RecQL (human helicase Q1) which has homology with the Escherichia coli RecQ protein and found that they encode two isoforms. The two isoforms are identical over the entire sequence except for the carboxyl terminal sequence spanning less than 30 amino acids. One of the two isoforms, alpha, contains a sequence, KKRK, in the carboxyl terminus, which is also contained in human helicase Q1 and was confirmed to function as the nuclear localization signal. The other form, beta, does not contain such a sequence. Expression of mouse helicase Q1 mRNA is extremely and relatively high in the testis and the thymus, respectively. RT-PCR analysis revealed that helicase Q1alpha was expressed in all tissues tested and the beta form was expressed only in the testis. A survey of expression of Q1alpha and Q1beta mRNA in the testis after birth revealed that Q1alpha mRNA is expressed in all testes of mice aged from 7 days to 8 weeks, and the expression of Q1beta mRNA begins 14 days after birth, corresponding to the appearance of cells in the pachytene stage. 相似文献
45.
M Hanada S Mizuno A Fukushima Y Saito T Noguchi T Yamaoka 《Canadian Metallurgical Quarterly》1998,89(11):1229-1238
Amrubicin is a novel, completely synthetic 9-aminoanthracycline derivative. Amrubicin and its C-13 alcohol metabolite, amrubicinol, inhibited purified human DNA topoisomerase II (topo II). Compared with doxorubicin (DXR), amrubicin and amrubicinol induced extensive DNA-protein complex formation and double-strand DNA breaks in CCRF-CEM cells and KU-2 cells. In this study, we found that ICRF-193, a topo II catalytic inhibitor, antagonized both DNA-protein complex formation and double-strand DNA breaks induced by amrubicin and amrubicinol. Coordinately, cell growth inhibition induced by amrubicin and amrubicinol, but not that induced by DXR, was antagonized by ICRF-193. Taken together, these findings indicate that the cell growth-inhibitory effects of amrubicin and amrubicinol are due to DNA-protein complex formation followed by double-strand DNA breaks, which are mediated by topo II. 相似文献
46.
J Yamaoka S Yamasaki H Kurazono S Imamura M Noda K Miyai Y Takeda 《Canadian Metallurgical Quarterly》1997,23(5):297-302
PURPOSE: To determine the maximum tolerated dose, toxicities, and potential antitumor activity of edatrexate (E), an antifolate agent with enhanced in vitro antitumor activity as compared with methotrexate (M), when given in combination with vinblastine, doxorubicin, cisplatin, and filgrastim (G-CSF) to patients with advanced malignancies. PATIENTS AND METHODS: Thirty-seven patients with advanced malignancies were treated with escalating doses of edatrexate in combination with vinblastine (V), doxorubicin (A), cisplatin (C), and filgrastim (EVAC/G-CSF) following three different subsequently developed schedules. Schedule 1 was patterned after the MVAC regimen, a combination chemotherapy program with activity against different epithelial malignancies, and consisted of E, 40 mg/m2/day, days 1/15/22; V, 3 mg/m2/day, days 2/15/22; A, 30 mg/m2/ day, day 2; C, 70 mg/m2/day, day 2; repeated every 28 days. Schedules 2 and 3 were designed to avoid observed dose-limiting toxicity on schedule 1 consisting of transient elevation of serum creatinine levels and delayed myelosuppression. Schedule 2 consisted of E, 40 or 60 mg/ m2/day, days 1 and 15; V, 3 mg/m2/day, days 2 and 15; A, 30 mg/m2/day, day 2; C, 30 mg/m2/day, days 1 and 2; cycled every 28 days. Schedule 3 consisted of E, 60 to 120 mg/m2/day, day 1; V, 3 mg/m2/day, day 2; A, 30 mg/m2/day, day 2; C, 30 mg/m2/day, days 1 and 2; cycled every 21 days. Filgrastim 5 micrograms/kg/day was given to all patients subcutaneously until the absolute neutrophil count was greater than 10,000/microL postnadir. Three patients were treated on schedule 1, 10 on schedule 2 (four at an E dose of 40 mg/m2/day and six at an E dose of 60 mg/m2/day), and 24 on schedule 3 (six at each of the following E dosages: 60, 80, 100, and 120 mg/m2/day). RESULTS: Dose-limiting toxicities of grade 3 to 4 leukopenia and transient elevation of serum creatinine values were observed in two of three patients treated on schedule 1. A dose-limiting toxicity of grade 3 to 4 leukopenia was noted in two of six patients treated on schedule 2 at an edatrexate dose of 60 mg/m2/day. Two of six patients treated on schedule 3 at an edatrexate dose of 120 mg/m2/day had a dose-limiting toxicity of grade 3 stomatitis (one patient) and grade 3 cytopenia (one patient). Nineteen of 37 patients with evaluable or measurable disease had a response to treatment (response rate 51%, 95% confidence intervals = 35%-67%). Nine of 15 patients with metastatic non-small cell lung cancer responded, including one complete remission (response rate 60%, confidence intervals = 35%-85%). A median survival of 517 days (confidence interval = 163-808 days) and a 1-year survival rate of 60% (confidence interval = 35%-85%) was seen in patients with advanced non-small cell lung cancer. CONCLUSIONS: The maximum tolerated dose and the recommended phase II dose of edatrexate is 100 mg/m2/day when administered as part of the EVAC/G-CSF program following schedule 3. Promising antineoplastic activity against non-small cell lung carcinomas was observed, and a phase II study is planned. 相似文献
47.
T Takahashi S Yagishita N Amano K Yamaoka T Kamei 《Canadian Metallurgical Quarterly》1997,94(3):294-299
The use of biomarkers is a promising approach to the study of human cancer risk. Bronchial metaplasia in sputum cytology may be a marker for potential premalignancy that can be used for population studies. We recently performed a randomized, controlled trial in smokers on the effect of 14 weeks beta-carotene (20mg/day) on markers for DNA damage. We now have evaluated the application of sputum cytology in this study and performed a preliminary evaluation of the effect of beta-carotene. Of the 150 potential participants in this trial 75 were not eligible because they failed to produce sputum samples (n = 29), or because samples were unsatisfactory (n = 46). The eligible group was older (41 vs 37 years) and had smoked longer (23 vs 19 years), but had similar cigarette consumption (mean 21/day) and plasma cotinine levels. Metaplasia was graded in seven categories. Only 11 subjects (15%) showed minor or mild atypia on study entry. Agreement within and between observers was 95% within the same or an adjacent category. We observed no significant correlation between before and after treatment final metaplasia scores in either the beta-carotene (Spearman R = 0.18, P = 0.3) or placebo group (Spearman R = 0.17, P = 0.3). Initial metaplasia scores were somewhat higher in the beta-carotene group (n = 33) than in the placebo group (n = 42) (P = 0.06). Final metaplasia scores were similar in both groups (P = 0.69), and there was no decrease in metaplasia scores in the beta-carotene group (P = 0.75). This study indicates that sputum cytology may not yet be a readily applicable marker in studies of a healthy asymptomatic population, because many smokers do not spontaneously produce sputum, more severe lesions are rare, and variation over time in the minor lesions in large. Therefore, the preliminary evidence that beta-carotene has no influence should be interpreted with care. 相似文献
48.
C Tanaka K Yoshimoto S Yamada H Nishioka S Ii M Moritani T Yamaoka M Itakura 《Canadian Metallurgical Quarterly》1998,83(3):960-965
Germ-line mutations of the MEN1 gene were analyzed in five cases of familial and four cases of sporadic multiple endocrine neoplasia type 1 (MEN-1), six cases in three independent pedigrees of familial pituitary adenoma without MEN-1, and three cases of familial isolated primary hyperparathyroidism (FIHP) in Japanese. Eight different types of germ-line mutations in all nine cases of MEN-1 were distributed in exons 2, 3, 7, and 10 and intron 7 of the MEN1 gene. Loss of heterozygosity (LOH) on 11q13 was detected in all nine tumors of these cases with microsatellite analysis. No germ-line mutation of the MEN1 gene was detected in three pedigrees of familial pituitary adenoma and three cases of FIHP. LOH on 11q13 was detected in two cases in one pedigree of familial pituitary adenoma, and one of them showed a heterozygous somatic mutation of the MEN1 gene. No LOH on 11q13 was detected in three cases of FIHP. Based on these, we conclude that the loss of function of menin is etiological for familial or sporadic MEN-1, but not for FIHP or most familial pituitary adenoma without MEN-1. 相似文献
49.
T Yago M Tsukuda H Fukushima H Yamaoka K Kurata-Miura T Nishi M Minami 《Canadian Metallurgical Quarterly》1998,161(3):1140-1145
This study examined the adhesive interactions of peripheral blood NK cells with P- and E-selectin and analyzed the effect of IL-12 on the binding of NK cells to these selectins. P-selectin glycoprotein ligand-1 (PSGL-1) is expressed on most resting and IL-12-activated NK cells. However, the percentage of resting NK cells bound to P-selectin-IgG was 15%, and that of activated NK cells bound to P-selectin-IgG was 65%. Furthermore, the number of IL-12-activated NK cells bound to P-selectin-transfected Chinese hamster ovary cells was significantly higher than that of resting NK cells under flow conditions. These interactions were abolished by the incubation of these NK cells with anti-PSGL-1 (PL-1) mAb. Thus, PSGL-1/P-selectin interaction is important in the binding of resting and activated NK cells to P-selectin. NK cells express sialyl-Lewis(x) (sLe(x)) structure recognized by anti-sLe(x) mAb (KM-93), and IL-12 activation of NK cells increased the mean fluorescence intensity of KM-93-reactive NK cells. Adhesion of IL-12-activated NK cells to E-selectin-transfected Chinese hamster ovary cells was stronger than that of resting NK cells under flow conditions. These interactions were reduced markedly by incubation with anti-sLe(x) mAb. Thus, sLe(x) is the major ligand of resting and activated NK cells for E-selectin. These findings indicate that IL-12 stimulation of NK cells promotes their adhesion activity to endothelial selectins. 相似文献
50.
H Niiro T Otsuka E Ogami K Yamaoka S Nagano M Akahoshi H Nakashima Y Arinobu K Izuhara Y Niho 《Canadian Metallurgical Quarterly》1998,250(2):200-205
Herein we describe a new test system to produce a standardized partial muscle-tendon junction (MTJ) stretch injury. In anesthetized rabbits the tibialis anterior (TA) muscle-tendon unit is unilaterally shortened using a custom designed clamp roller system. An angular displacement (average velocity of 450 degrees x s[-1]) is applied about the foot to plantarflex the ankle 90 degrees while the lower extremity is fixed. During ankle rotation the TA muscle is tetanically stimulated to generate an eccentric stretch injury at the MTJ. Forty-eight hours after injury, isometric torque deficit (injured/sham) was measured. Two groups of animals (N = 6 in each group) were tested with the only difference between the two groups being the initial tendon shortening. In Group 1 (tendon shortening = 1.2 cm. N = 6) the torque deficit was 36.7+/-5.9% (mean+/-SD). In Group 2 (tendon shortening = 1.5 cm. N = 6) the torque deficit was 58.7+/-7.4% (mean+/-SD). No order effect was suggested by the data (P = 0.6062), but the difference in torque deficit between the two groups was highly significant (P = 0.0001). For all tests in which the tendon was temporarily shortened before muscle stimulation and stretch (N = 12) there was a visible hematoma at the MTJ similar to the injury that is common in athletic injuries. Histological evaluation 48 h after injury revealed both fiber tearing and inflammation at the MTJ. In addition, there was focal fiber damage in the muscle belly for both groups. The damage and inflammatory process, however, were more severe in the group with greater initial tendon shortening. 相似文献