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991.
AD Spiegel 《Canadian Metallurgical Quarterly》1993,93(3):190-193
Abomasal fistulae resulting from right paramedian abomasopexy in eight adult dairy cattle were treated by primary closure of the abdominal wall after surgical resection of the fistulae. The median elapsed time from the abomasopexy to recognition of fistula formation was 16 days (range, 10 to 90 days). All cows had normal electrolyte values, and five cows had mildly increased base excess values (range = 4.0 to 7.8 mEq/L). Surgery was performed with the cows in dorsal recumbency using general anesthesia. The fistulated tissue was resected and the abomasum and body wall were closed primarily. One or two layers of appositional sutures using #2 or #3 polyglactin 910 were used to close the body wall. Mean surgical time was 2.2 hours (range, 1.8 to 2.9 hours). Two cows were lost to follow-up. Five of the remaining six cows returned to production (range, 5 to 30 months). Primary closure of the abdominal wall should be considered in the surgical repair of abomasal fistulae in cows that do not have diffuse peritonitis. 相似文献
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993.
A modified method of applying ZnSO4 to the olfactory mucosa is described. Treated rats experienced severe nasal congestion that cleared within 24 h; more persistent morbidity did not occur. Nonpregnant females observed with male intruders 24 h following ZnSO4 showed no alterations in behavior other than a reduction in anogenital sniffing, indicating that they were not hypoactive or irritable. In other experiments, lactating females were observed in a hole-board apparatus; 2 days posttreatment anosmia was confirmed in 80% of bilaterally ZnSO4-treated females by the absence of preference for pup odors. After bilateral but not unilateral ZnSO4 treatment, initially activity scores and nose pokes were equivalent in all groups, but later they both were lower than in controls, probably due to a more rapid habituation to the novel apparatus. We conclude that intranasal ZnSO4 by small-volume spray is a useful experimental tool. 相似文献
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996.
K. R. Allakhverdiev A. I. Baranov T. G. Mamedov V. A. Sandler Ya. N. Sharifov A. V. Shubnikov 《Ferroelectrics Letters Section》1988,8(5):125-133
The temperature dependences of the dielectric properties, conductivity, spontaneous polarization as well as the effect of hydrostatic pressure on the anomalies of these properties have been investigated. The β-TlInS2 crystals are shown to be often a mixture of the polytypes. Transition into a ferroelectric state for some of the β-TlInS2 polytypes is not preceded by an incommensurats phase transition. 相似文献
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Prostaglandin (PG) E2 acts on the brain stem to modulate breathing activity in the ovine fetus. The source of this PGE2 is unknown and we hypothesized that it is produced locally in the developing brain and functions in a paracrine and/or autocrine manner. The purpose of the present study was to establish whether prostaglandin-H synthase-1 (PGHS-1), a crucial enzyme in de novo prostaglandin synthesis, is present and its gene expressed in the ovine fetal brain. Immunohistochemical and molecular hybridization techniques were used to identify sites of PGHS-1 immunoreactivity and PGHS-1 mRNA expression respectively in the brain of the ovine fetus in late gestation (approximately 126 days gestation, term 145 days). PGHS-1 immunoreactivity was localized to specific regions of the fetal brain, including the cortex, hypothalamus, hippocampal formation, superior colliculus of the midbrain, parabrachial nucleus of the pons, and the reticular formation, raphe, nucleus of the solitary tract, and gracile and cuneate nuclei of the medulla. The relative abundance of PGHS-1 mRNA in selected brain regions, as determined by Northern blot analysis, correlated qualitatively with the number of PGHS-1 immunoreactive neurons identified in each region. In situ hybridization demonstrated PGHS-1 mRNA to be localized in the same neurons or nuclei as PGHS-1 immunoreactivity. These results indicate that PGHS-1 synthesized de novo in many brain regions including two that are important in respiratory control: the pneumotaxic center (parabrachial nucleus) and the dorsal respiratory group (nucleus tractus solitarius) suggesting that prostaglandins that modulate fetal respiratory activity are synthesized endogenously. 相似文献
1000.