全文获取类型
收费全文 | 691篇 |
免费 | 0篇 |
专业分类
综合类 | 1篇 |
化学工业 | 1篇 |
机械仪表 | 1篇 |
无线电 | 1篇 |
一般工业技术 | 2篇 |
冶金工业 | 683篇 |
自动化技术 | 2篇 |
出版年
2002年 | 1篇 |
2001年 | 4篇 |
1999年 | 11篇 |
1998年 | 190篇 |
1997年 | 92篇 |
1996年 | 83篇 |
1995年 | 28篇 |
1994年 | 40篇 |
1993年 | 44篇 |
1992年 | 6篇 |
1991年 | 17篇 |
1990年 | 13篇 |
1989年 | 10篇 |
1988年 | 11篇 |
1987年 | 8篇 |
1986年 | 17篇 |
1985年 | 7篇 |
1983年 | 2篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 6篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 28篇 |
1976年 | 53篇 |
1975年 | 3篇 |
1965年 | 1篇 |
1955年 | 2篇 |
排序方式: 共有691条查询结果,搜索用时 15 毫秒
51.
52.
53.
RC Stern TF Boat DM Orenstein RE Wood LW Matthews CF Doershuk 《Canadian Metallurgical Quarterly》1978,118(5):821-826
Studies are presented of the effect of procaine group anesthetics on rat brain synaptosome stability to dodecyl sulfate and on catalytic properties of the membrane bound alkaline phosphatase. The dose curves of detergent stability are characterized by two maxima, one at 3.10(-4) M for tetracaine, 2.10(-6) M for lidocaine and 5.10(-5) M for procaine; the other being at 10(-3) M for all anesthetics. The curves of Vmax and KM versus procaine concentration to exhibit the minimum at 5.10(-7) M and maximum at 3,2.10(-6) M. Procaine at 5.10(-7) M increases enthalpy and enthropy of membraneous alkaline phosphatase. It is suggested that interactions between anesthetics and centers of high affinity lead to synaptosome structural rearrangements, which affect the properties of membraneous enzymes. 相似文献
54.
55.
56.
57.
1. Using an in vitro everted gut sac method based on that of Wilson & Wiseman (1954), a number of amino penicillins were tested in order to identify the involvement of any specialized transport mechanisms in their absorption across rat intestine. 2. Only one of the amino penicillins, cyclacillin (1-amino-cyclohexyl penicillin) was shown to be actively transported. The other penicillins appeared to diffuse passively across the intestine. 3. Cyclacillin was found to concentrate against a gradient at 37 degrees C but not at 19 degrees C. 4. Transport of cyclacillin across the mucosal membrane was saturated at mucosal concentrations greater than 1000 microgram/ml. 5. The rate of the forward flux of cyclacillin was many times that of its back flux. 6. No relationship between the active transport of cyclacillin and that of amino acids could be demonstrated. 相似文献
58.
59.
60.
A randomized controlled trial of home care: clinical outcome for five surgical procedures 总被引:1,自引:0,他引:1
The clinical function of patients receiving home care after five surgical procedures was assessed. Hospital patients who normally would have received minimal nursing care at the end of their hospital stay were randomly assigned to an experimental home-care group or a control group who were discharged from hospital after the normal length of stay. Comprisons of "untoward events" (discomfort, infection, delayed healing, or complications) are reported for the two groups in five surgical categories (varicose vein stripping, herniorrhaphy, cholecystectomy, anal and rectal operations and abdominal hysterectomy) where the home-care program operated efficientyl. No apparent differences in the rates of untoward events were noted between hospital and home-care groups. It is concluded that home care should be considered for reasons other than clinical function, such as socio-economic functioning, the wishes of the patient, or more efficient use of hospital space. 相似文献