全文获取类型
收费全文 | 1572篇 |
免费 | 0篇 |
专业分类
化学工业 | 3篇 |
建筑科学 | 3篇 |
水利工程 | 1篇 |
无线电 | 1篇 |
一般工业技术 | 2篇 |
冶金工业 | 1561篇 |
自动化技术 | 1篇 |
出版年
2010年 | 1篇 |
2009年 | 1篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2003年 | 3篇 |
1999年 | 57篇 |
1998年 | 461篇 |
1997年 | 283篇 |
1996年 | 191篇 |
1995年 | 101篇 |
1994年 | 69篇 |
1993年 | 103篇 |
1992年 | 9篇 |
1991年 | 19篇 |
1990年 | 9篇 |
1989年 | 13篇 |
1988年 | 14篇 |
1987年 | 12篇 |
1986年 | 12篇 |
1985年 | 12篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1981年 | 8篇 |
1980年 | 10篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 52篇 |
1976年 | 105篇 |
1975年 | 6篇 |
1965年 | 1篇 |
1955年 | 2篇 |
1954年 | 1篇 |
排序方式: 共有1572条查询结果,搜索用时 15 毫秒
101.
102.
103.
A case of uremia resulting from bilateral Hodgkin's lymphomatous infiltration of kidneys is reported. Uremia was an initial feature in the case and was the eventual cause of death. 相似文献
104.
105.
Microscopic cysts in the permanent cortices of adrenal glands were studied in a series of 274 infants, some of whom had been stillborn and none of whom were more than 12 months old. After correction for length of gestation, there were no significant relationships between the occurence and number of microcysts and various maternal, placental, and perinatal diseases. A significant direct correlation was demonstrated statistically with shorter gestational period and shorter survival time after birth. We concluded that the adrenal microcysts are either a developmental feature or the result of a greater susceptibility to stress in the fetus and newborn than in older infants. 相似文献
106.
107.
AE Kammer 《Canadian Metallurgical Quarterly》1976,35(9):1992-1999
In insects gas exchange may be: 1) entirely passive, when metabolic rate is low; 2) enhanced automatically by muscle contractions that produce movements, e.g., wing movements in flight; or 3) produced by ventilatory movements, particularly of the abdomen. In terrestrial insects such as locusts and cockroaches ventilatory movements are governed by a dominant oscillator in the metathoracic or anterior abdominal ganglion. The dominant oscillator overrides local oscillators in the abdominal ganglia and thus sets the rhythm for the entire abdomen, and it also controls spiracle opening and closing in several thoracic and abdominal segments. This ventilatory control mechanism appears to be different from that generating metachronal rhythms such as occur in the ventilatory and locomotory movements of aquatic arthropods. There are now several examples of rhythms, both ventilatory and locomotory, that can be generated by the central nervous system in the absence of phasic sensory feedback, but the mechanism of rhythm production is not known. Studies of ganglionic output suggest that neuronal oscillators can produce a range of frequencies and that some oscillators may be employed in more than one function or behavior. The mechanisms by which central oscillators are coupled to the output motorneurons are also not known; large phase changes suggest that in some cases different coupling interneurons are active. Intracellular recordings from identified neurons have begun to clarify the important roles of interneurons in the production of motor patterns. 相似文献
108.
YQ Huang JJ Li A Nicolaides WG Zhang AE Friedman-Kien 《Canadian Metallurgical Quarterly》1993,13(4):887-890
Growth factors, such as bFGF, have been shown to exert autocrine and paracrine effects on the growth of Kaposi's Sarcoma (KS)-derived cells, which suggested that the inhibitors of angiogenesis may be promising for KS treatment. However, KS lesions have been found to continue to enlarge after patients had been treated with FGF binding antagonists such as suramin. We investigated the effect of protamine and suramine on the growth of KS derived cells in vitro. Although both of these agents which are FGF binding antagonists were found to inhibit the incorporation of 3H thymidine in KS-derived cultured cells, increased expression of bFGF, FGF5 and the FGF receptor was observed after the KS cells were exposed to these substances. These results might explain the clinical observation that FGF binding antagonists such as suramin caused an apparent stimulation of KS tumor growth when administered systemically to patients with AIDS-related KS. 相似文献
109.
M de Haas JM Kerst CE van der Schoot J Calafat CE Hack JH Nuijens D Roos RH van Oers AE von dem Borne 《Canadian Metallurgical Quarterly》1994,84(11):3885-3894
In four healthy volunteers, we analyzed in detail the immediate in vivo effects on circulating neutrophils of subcutaneous administration of 300 micrograms of granulocyte colony-stimulating factor (G-CSF). Neutrophil activation was assessed by measurement of degranulation. Mobilization of secretory vesicles was shown by a decrease in leukocyte alkaline phosphatase content of the circulating neutrophils. Furthermore, shortly postinjection, Fc gamma RIII was found to be upregulated from an intracellular pool that we identified by immunoelectron microscopy as secretory vesicles. Intravascular release of specific granules was shown by increased plasma levels of lactoferrin and by upregulation of the expression of CD66b and CD11b on circulating neutrophils. Moreover, measurement of fourfold elevated plasma levels of elastase, bound to its physiologic inhibitor alpha 1-antitrypsin, indicated mobilization of azurophil granules. However, no expression of CD63, a marker of azurophil granules, was observed on circulating neutrophils. G-CSF--induced mobilization of secretory vesicles and specific granules could be mimicked in whole blood cultures in vitro, in contrast to release of azurophil granules. Therefore, we postulate that the most activated neutrophils leave the circulation, as observed shortly postinjection, and undergo subsequent stimulation in the endothelial microenvironment, resulting in mobilization of azurophil granules. Our data demonstrate that G-CSF should be regarded as a potent immediate activator of neutrophils in vivo. 相似文献
110.
AE Eggen 《Canadian Metallurgical Quarterly》1993,46(11):1297-1304
In a cross-sectional survey carried out in Troms? in 1986-7, 19,137 men and women aged 12-56 years from the general population were asked about their use of drugs during the preceding 14 days. Use of analgesics was very common. On average 28% of the women and 13% of the men had used analgesics. Drug use due to menstruation discomfort contributed only partly to the gender difference. Drug use was independent of age from 20 years of age. Factors having an impact on analgesic drug use were analyzed by logistic regression. The most significant predictors of analgesic use were suffering from headache (OR = 14.2(women) OR = 24.4(men)) and infections (OR = 2.0(women) OR = 2.4(men)). Drug users also tended to suffer from symptoms of depression (women) and sleeplessness (men). Lifestyle and sociodemographic factors were also significant predictors, but were of marginal importance (OR < 1.5) compared with occurrence of pain and infections. 相似文献