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121.
Women with recurrent endometrial carcinoma are usually not considered candidates for pelvic exenteration. To assess the efficacy of this procedure, the records of all patients undergoing pelvic exenteration for adenocarcinoma of the endometrium at four institutions from 1955 through 1988 were reviewed. Of the 31 procedures performed, 7 were for primary therapy and 4 were judged to be palliative in nature and were excluded from analysis. Of the 20 patients with recurrent endometrial cancer who underwent exenteration with curative intent, all had previously received pelvic radiotherapy, 14 as part of their primary treatment and 6 as part of the treatment of recurrent disease. Six of 20 patients also received chemotherapy or hormonal therapy prior to exenteration. The median patient age was 65 years (range 44-79 years). At most recent follow-up, 8 patients were alive and disease free, 2 were alive with disease, 6 had died of disease, and 4 had died of other causes. The median follow-up of living patients is 89 months. Twelve of 20 patients experienced major complications, the most common of which was neovaginal flap necrosis. Of the 20 patients, 1 patient (5%) died in 1963 of surgical complications. The Kaplan-Meier estimate of 5-year disease-free survival is 45%. Pelvic exenteration can produce an acceptable rate of disease-free survival in highly selected patients with local recurrence of endometrial adenocarcinoma who have exhausted other treatment modalities. 相似文献
122.
N Cossons TO Nielsen C Dini N Tomilin DB Young KT Riabowol JB Rattner RN Johnston M Zannis-Hadjopoulos GB Price 《Canadian Metallurgical Quarterly》1997,67(4):439-450
Three different mammalian origins of DNA replication, 343, S3, and X24, have been cloned into a 15.8 kb circular yeast vector pYACneo. Subsequent transfection into HeLa cells resulted in the isolation of several stably maintained clones. Two cell lines, C343e2 and CS3e1, were found to have sequences maintained as episomes in long-term culture with a stability per generation of approximately 80%. Both episomes also contain matrix attachment region (MAR) sequences which mediate the binding of DNA to the nuclear skeleton and are thought to play a role in DNA replication. Using high salt extraction of the nucleus and fluorescent in situ hybridization, we were able to demonstrate an association of the 343 episome with the nuclear matrix, most probably through functional MAR sequences that allow an association with the nuclear matrix and associated regions containing essential replication proteins. The presence of functional MARs in small episomal sequences may facilitate the replication and maintenance of transfected DNA as an episome and improve their utility as small episomal constructs, potential microchromosomes. 相似文献
123.
TO Larsen 《Canadian Metallurgical Quarterly》1997,24(6):463-466
We report a rare case of psammocarcinoma which presented as a mass in the lower abdomen of an otherwise asymptomatic woman. Ultrasonographically, the tumor showed extensive calcification and was suspected to be a myoma. DNA image cytometry and assessment of proliferative activity were performed and showed an euploid, low proliferating tumor cell population. This underlines the low malignancy of this type of carcinoma, which is comparable to that of serous borderline lesions of the ovary and explains the benign clinical course. 相似文献
124.
For many neuromuscular disorders, the chromosomal location is known, the causal gene has been identified, and direct application of this knowledge may be made in a clinical setting. The benefits resulting from molecular-based methods include improved diagnostic accuracy and genetic counseling for patients and other at risk family members. This chapter discusses in detail four of the most frequently encountered neuromuscular disorders. These diseases include spinal muscular atrophy, Charcot-Marie-Tooth neuropathy, Duchenne/Becker type muscular dystrophy, and myotonic dystrophy. 相似文献
125.
126.
To attempt to understand the physical principles underlying protein crystallization, an algorithm is described for simulating the crystal nucleation event computationally. The validity of the approach is supported by its ability to reproduce closely the wellknown preference of proteins for particular space group symmetries. The success of the algorithm supports a recent argument that protein crystallization is limited primarily by the entropic effects of geometric restrictions imposed during nucleation, rather than particular energetic factors. These simulations provide a new tool for attacking the problem of protein crystallization by allowing quantitative evaluation of new ideas such as the use of racemic protein mixtures. 相似文献
127.
Current models of platelet-derived growth factor (PDGF) beta receptor itinerary are based upon the properties of receptors recovered from nonionic detergent-solubilized cellular extracts. Comparing several commonly used cell extraction procedures, we have determined that up to 50% of immunoreactive PDGF beta receptors, reside in a Triton X-100 insoluble pool in a wide distribution of cultured cell lines, including Balb/c-3T3, NIH 3T3, and Swiss fibroblasts, primary murine and human fibroblasts, and primary human glial cells. Many properties of Triton insoluble receptors are distinct from the well-characterized PDGF beta receptors, including 1) delayed arrival of newly synthesized receptors into the Triton insoluble fraction, 2) prolonged half-life in the presence of PDGF, 3) increased abundance with increasing cell density, 4) inaccessibility to modification by extracellular compartment enzymes, 5) cofractionation with cytoskeletal proteins, and 6) a higher basal tyrosine phosphorylation state. PDGF stimulates accumulation of tyrosine phosphorylated PDGF beta receptors in the Triton X-100 insoluble fraction. Cell surface PDGF beta receptors modified by enzymatic desialylation redistribute to the insoluble fraction. These findings distinguish the itinerary of a large subpopulation of PDGF beta receptors from those characterized previously. Receptors in this fraction represent a long-lived tyrosine phosphorylated population that may effect responses for extended periods following ligand activation. 相似文献
128.
129.
WJ Powers JL Rosenbaum CS Dence J Markham TO Videen 《Canadian Metallurgical Quarterly》1998,18(6):632-638
Few data regarding early developmental changes in cerebral (blood-to-brain) glucose transport (CTXglc) and CMRglc are available for humans. We measured CBF, CTXglc, and CMRglc with positron emission tomography at 4 to 7 days of life in six preterm human infants whose estimated gestational age was 25 to 34 weeks. The Michaelis-Menten constants Kt and Tmax were estimated from CTXglc and the calculated cerebral capillary plasma glucose concentration. Mean CMRglc was 8.8 mumol 100 g-1 min-1. The CMRglc did not correlate with plasma glucose concentration (r = .315, P = .543), whereas CTXglc showed a significant correlation with plasma glucose concentration (r = .836, P = .038). Estimation of the Michaelis-Menten constants from the best fit to the measured data produced values of Kt = 6.0 mumol mL-1 and Tmax = 32.6 mumol 100 g-1 min-1. These values for Kt in the developing human brain are similar to those that have been reported for the mature brain of adolescent and adult humans and adult nonhuman primates, indicating the affinity of the glucose transport protein for D-glucose is similar. However, Tmax is approximately one third to one half of the comparable values for mature brain, indicating a reduced number of available luminal transporters. 相似文献
130.
MW Beckmann D Niederacher R Bodden-Heidrich TO Goecke B Kuschel M Achnoula F Aba HG Schnürch HG Bender 《Canadian Metallurgical Quarterly》1998,87(15):511-515
Germline mutations of the cancer susceptibility genes BRCA1 and BRCA2 seem to lead to a very high risk for breast and/or ovarian cancer. Therefore, genetic counselling and identification of high-risk families may be essential to offer the opportunity to participate in a specific early cancer detection program and to provide individualized psychological support. In a two year period (August 1994-August 1997) 304 consultees present for genetic counselling at the interdisciplinary cancer genetic clinic (Department of Obstetrics & Gynecology and Human Genetics, Heinrich-Heine-Universit?t, Düsseldorf). For genetic testing a BRCA1/2 mutation detection strategy including protein truncation test (PTT), single strand conformation polymorphism (SSCP), and direct DNA sequencing is used. 161 families fulfilled the inclusion criteria; at present, 72 families for whom complete analytical material is available are analyzed. Although genetic testing for BRCA1 and BRCA2 is technically challenging, women with a family history of multiple sporadic breast/ovarian cancers and those with a hereditary BRCA1 and BRCA2 gene defect may be distinguished. For the first group of consultees this may ease their concern, for the second group preventive measures including an early cancer detection or prevention program, psychological support or prophylactic surgery may be discussed. 相似文献