全文获取类型
收费全文 | 322篇 |
免费 | 1篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 1篇 |
能源动力 | 1篇 |
轻工业 | 13篇 |
无线电 | 1篇 |
一般工业技术 | 1篇 |
冶金工业 | 304篇 |
自动化技术 | 1篇 |
出版年
2017年 | 1篇 |
2014年 | 1篇 |
2013年 | 1篇 |
2011年 | 1篇 |
2010年 | 2篇 |
2009年 | 1篇 |
2008年 | 1篇 |
2007年 | 1篇 |
2006年 | 2篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 1篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 76篇 |
1997年 | 34篇 |
1996年 | 43篇 |
1995年 | 24篇 |
1994年 | 11篇 |
1993年 | 11篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 5篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 2篇 |
1982年 | 4篇 |
1981年 | 7篇 |
1980年 | 8篇 |
1977年 | 27篇 |
1976年 | 37篇 |
排序方式: 共有323条查询结果,搜索用时 281 毫秒
81.
S He RP Mason S Hunjan VD Mehta V Arora R Katipally PV Kulkarni PP Antich 《Canadian Metallurgical Quarterly》1998,6(9):1631-1639
Phytochemicals such as indole-3-carbinol (I3C) and sulforaphane are components of cruciferous vegetables which exhibit antitumorigenic activity associated with altered carcinogen metabolism and detoxification. Diindolylmethane (DIM) is a major acid-catalyzed metabolite of I3C formed in the gut that binds to the aryl hydrocarbon receptor (AhR) and treatment of MCF-7 human breast cancer cells with 10-50 microM DIM resulted in rapid formation of the nuclear AhR complex and induction of CYP1A1 gene expression was observed at concentrations >50 microM. Previous studies have demonstrated that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a high affinity AhR ligand, inhibits 17beta-estradiol (E2)-induced responses in MCF-7 cells and growth of E2-dependent 7,12-dimethylbenzanthracene (DMBA)-induced mammary tumors in female Sprague-Dawley rats. Results of this study show that like TCDD, DIM inhibits E2-induced proliferation of MCF-7 cells, reporter gene activity in cells transiently transfected with an E2-responsive plasmid (containing a frog vitellogenin A2 gene promoter insert) and down-regulates the nuclear estrogen receptor. Moreover, DIM (5 mg/kg every other day) also inhibits DMBA-induced mammary tumor growth in Sprague-Dawley rats and this was not accompanied by induction of hepatic CYP1A1-dependent activity. Thus, DIM represents a new class of relatively non-toxic AhR-based antiestrogens that inhibit E2-dependent tumor growth in rodents and current studies are focused on development of analogs for clinical treatment of breast cancer. 相似文献
82.
83.
SCOPE OF THE STUDY: We studied the possibility to examine position and determination of IOL and capsular bag supporting ring. PATIENTS AND METHODS: We showed in ten human eyes the identification of capsular bag supporting ring (PMMA, 12,5 mm open diameter) and intraocular lenses (IOL, 13,5 mm diameter) and haptics by ultrasound biomicroscopy in radar and limbus parallel scans 12 to 18 months post operation. RESULTS: Both alloplastic implantates show typical sceems of reflection and could be differentiated by ultrasoundbiomicroscopy. In eyes with zonulolysis up to 6 hours a good centration of capsular bag supporting ring and IOL had been seen, with more zonulolyses a slight subluxation could been shown. CONCLUSION: Ultrasound biomicroscopy is a good method to determine the position of intraocular lens and capsular bag supporting ring. 相似文献
84.
AE Rudenko FP Trinus LV Korzhenevski? TA Bukhtiarova AZ Koval' VD Maly? OV Novikova EV Tkachenko 《Canadian Metallurgical Quarterly》1996,(5-6):134-136
The authors submit results of treatment of patients having suffered from postherpetic pain syndrome (herpetic ganglionitis of the cervical, thoracic, lumbosacral localization, postherpetic intercostal neuralgia, ganglionitis of the trigeminal nerve). In viral diseases, amizone has marked analgetic, antiinflammatory, and immunomodulating effects. The drug is well tolerated by patients, is not associated with side effects under prescribed doses (0.25-0.75 as one dose on a three- or four-times daily schedule during the course of treatment lasting three or four weeks). The drug preparation in question is less effective in the treatment of chronic recurring post-therapeutic intercostal neuralgias, radiculalgia. 相似文献
85.
Scanning electron microscopy (SEM) of red blood cells in whole blood samples from rats was performed following acute gamma-irradiation of animals with 0.25 to 1 Gy. Increased incidence of echinocytosis was observed and found to be dose- and time-dependent. At a higher radiation dose (1 Gy), echinocytosis was revealed within 5 minutes after treatment and persisted up to 3 weeks. The data demonstrate the applicability of SEM for detecting minimal radiation-induced lesions of red blood cells. 相似文献
86.
87.
RD Bolton MD Cooper JS Frank AL Hallin PA Heusi CM Hoffman GE Hogan FG Mariam HS Matis RE Mischke LE Piilonen VD Sandberg GH Sanders U Sennhauser R Werbeck RA Williams SL Wilson R Hofstadter EB Hughes MW Ritter D Grosnick SC Wright VL Highland J McDonough 《Canadian Metallurgical Quarterly》1988,38(7):2077-2101
88.
PL Dutton CC Moser VD Sled F Daldal T Ohnishi 《Canadian Metallurgical Quarterly》1998,1364(2):245-257
We examined whether baroreceptor activation causes a release of acetylcholine (ACh) in the rostral ventrolateral medulla (RVLM) of the rat, in order to investigate a possible connection between RVLM cholinergic systems and cardiovascular baroreflexes. Male Wistar rats were anesthetized, paralyzed and artificially ventilated. Either electrical stimulation of aortic nerve or baroreceptor activation by intravenous phenylephrine produced an increase of the release of ACh in the RVLM, whereas baroreceptor denervation and tetrodotoxin (TTX) microinfusion in the RVLM inhibited the increase in ACh release induced by phenylephrine. TTX injected in the caudal ventrolateral medulla (CVLM) inhibited the phenylephrine-induced increase of ACh release. The excitatory amino acid L-glutamate microinfused in the CVLM produced an release in ACh release in the RVLM. These results suggest that there is a connection between RVLM cholinergic systems and cardiovascular baroreflexes. It is probable that neurons in the CVLM are involved in mediating the release of ACh in the RVLM. 相似文献
89.
90.
WJ Ciccone PS Fox M Neumyer D Rubens WM Parrish VD Pellegrini 《Canadian Metallurgical Quarterly》1998,80(8):1167-1174
Prospective data on 202 consecutive patients who had a total of 123 total hip and ninety-four total knee arthroplasties were collected from two university medical centers. The findings of routine surveillance for deep venous thrombosis performed with ascending contrast venography were compared with those of surveillance with duplex ultrasonography complemented with color-flow Doppler imaging. All of the studies were performed between the third and seventh postoperative days. Of the 202 patients (342 extremities) who were examined, fifty-five (27 per cent) were found to have deep venous thrombosis; fifty-two (95 per cent) of the thrombi were in the calf and three (5 per cent) were in the proximal veins. All of the thrombi were clinically asymptomatic and all were nonocclusive, allowing passage of contrast medium around an intraluminal filling defect. Duplex ultrasonography with color-flow Doppler imaging correctly identified two of the three proximal thrombi and five of the fifty-two thrombi in the calf (sensitivity, 10 per cent). The sensitivity for the detection of thrombi in the calf was zero of sixteen at one of the institutions involved in the study and 14 per cent (five of thirty-six) at the other. There were two false-positive findings on ultrasonographic examination; one involved a proximal thrombus and one, a distal thrombus. We believe that the interinstitutional variability and insensitivity of duplex ultrasonography with color-flow Doppler imaging for the detection of asymptomatic deep venous thrombi in the calf after total joint replacement make it unreliable as a routine surveillance tool after total hip or knee arthroplasty. 相似文献