全文获取类型
收费全文 | 1493篇 |
免费 | 1篇 |
专业分类
化学工业 | 7篇 |
轻工业 | 3篇 |
一般工业技术 | 3篇 |
冶金工业 | 1481篇 |
出版年
2015年 | 1篇 |
2013年 | 2篇 |
2012年 | 1篇 |
2010年 | 1篇 |
2006年 | 1篇 |
2003年 | 5篇 |
2002年 | 1篇 |
2000年 | 1篇 |
1999年 | 36篇 |
1998年 | 468篇 |
1997年 | 277篇 |
1996年 | 179篇 |
1995年 | 91篇 |
1994年 | 72篇 |
1993年 | 84篇 |
1992年 | 7篇 |
1991年 | 23篇 |
1990年 | 18篇 |
1989年 | 17篇 |
1988年 | 16篇 |
1987年 | 26篇 |
1986年 | 16篇 |
1985年 | 13篇 |
1982年 | 7篇 |
1981年 | 14篇 |
1980年 | 11篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1977年 | 24篇 |
1976年 | 75篇 |
1975年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有1494条查询结果,搜索用时 0 毫秒
991.
Kinesin-like calmodulin-binding protein (KCBP) is a recently identified novel kinesin-like protein that appears to be unique to and ubiquitous in plants. KCBP is distinct from all other known KLPs in having a calmodulin-binding domain adjacent to its motor domain. We have used different regions of KCBP to study its interaction with tubulin subunits and the regulation of this interaction by Ca(2+)-calmodulin. The results show that the carboxy-terminal part of the KCBP, with or without calmodulin-binding domain, binds to tubulin subunits and this binding is sensitive to nucleotides. In the presence of Ca(2+)-calmodulin the motor with calmodulin-binding domain does not bind to tubulin. This Ca(2+)-calmodulin modulation is abolished in the presence of antibodies specific to the calmodulin-binding domain of KCBP. Similar binding studies with the carboxy-terminal part of KCBP lacking the calmodulin-binding domain show no effect of Ca(2+)-calmodulin. These results indicate that Ca(2+)-calmodulin modulates the interaction of KCBP with tubulin subunits and this modulation is due to the calmodulin-binding domain in the KCBP. Calcium-dependent calmodulin modulation of KCBP interaction with tubulin suggests regulation of KCBP function by calcium, the first such regulation of a kinesin heavy chain among all the known kinesin-like proteins. 相似文献
992.
The kinesin-like calmodulin binding protein (KCBP) is a new member of the kinesin superfamily that appears to be present only in plants. The KCBP is unique in its ability to interact with calmodulin in a Ca2+-dependent manner. To study the interaction of the KCBP with microtubules, we expressed different regions of the Arabidopsis KCBP and used the purified proteins in cosedimentation assays with microtubules. The motor domain with or without the calmodulin binding domain bound to microtubules. The binding of the motor domain containing the calmodulin binding region to microtubules was inhibited by Ca2+-calmodulin. This Ca2+-calmodulin regulation of motor domain interactions with microtubules was abolished in the presence of antibodies specific to the calmodulin binding region. In addition, the binding of the motor domain lacking the calmodulin binding region to microtubules was not inhibited in the presence of Ca2+-calmodulin, suggesting an essential role for the calmodulin binding region in Ca2+-calmodulin modulation. Results of the cosedimentation assays with the N-terminal tail suggest the presence of a second microtubule binding site on the KCBP. However, the interaction of the N-terminal tail region of the KCBP with microtubules was insensitive to ATP. These data on the interaction of the KCBP with microtubules provide new insights into the functioning of the KCBP in plants. 相似文献
993.
994.
The species composition of microflora was determined and the etiological role of S. epidermidis was shown in some purulent inflammatory diseases (maxillary sinusitis, urethritis). The role of the complex of S. epidermidis persistence factors in the chronization of the infectious process and the formation of the resident carrier state was established. 相似文献
995.
Malignant hyperthermia is a rare complication in clinical anesthesia, especially associated with the administration of succinylcholine or inhalation anesthetics. A 19-year-old patient, suffering from traumatic mandible fracture, underwent open reduction under general anesthesia. Unfortunately, following administration of succinylcholine, he also suffered severe facial twitch and the first episode of hypercapnia. After adequate management, the symptoms subsided. However, two hours later, the hypercapnia recurred, combined with progressive elevation of body temperature. After administration of intravenous dantrolene 120 mg, the patient's condition became stable and the procedure was completed without sequelae. As the muscle contracture test is not available in Taiwan, the clinical grading scale is presented as an alternative diagnostic method for malignant hyperthermia. 相似文献
996.
RU Ostrovskaya GA Romanova SS Trofimov TA Gudasheva TA Voronina JA Halikas SB Seredenin 《Canadian Metallurgical Quarterly》1997,8(2-3):261-268
The present study investigated the potential benefit of the ethyl ester of N-phenylacetylprolylglycine (GVS-111) on the model of bilateral frontal lobectomy (BFL) in rats. The animals in Experiment 1 were trained in an active avoidance task and subsequently underwent BFL. The animals in Experiment 2 were first assessed in an open field and in a passive avoidance test before the BFL was performed. BFL dramatically decreased performance in the active avoidance test, disturbed habituation of horizontal activity in the open field and diminished the latency to enter the dark compartment in the passive avoidance test. GVS-111, administered in a dose of 0.5 mg/kg/day i.p. for 9 days following the operation, was found to improve performance in both active avoidance and passive avoidance and restored habituation of horizontal activity in the lobectomized animals. 相似文献
997.
998.
We show that among ecotypes of Arabidopsis, there is considerable variation in their susceptibility to crown gall disease. Differences in susceptibility are heritable and, in one ecotype, segregate as a single major contributing locus. In several ecotypes, recalcitrance to tumorigenesis results from decreased binding of Agrobacterium to inoculated root explants. The recalcitrance of another ecotype occurs at a late step in T-DNA transfer. Transient expression of a T-DNA-encoded beta-glucuronidase gusA gene is efficient, but the ecotype is deficient in crown gall tumorigenesis, transformation to kanamycin resistance, and stable GUS expression. This ecotype is also more sensitive to gamma radiation than is a susceptible ecotype. DNA gel blot analysis showed that after infection by Agrobacterium, less T-DNA was integrated into the genome of the recalcitrant ecotype than was integrated into the genome of a highly susceptible ecotype. 相似文献
999.
This report describes a rare, juxta-articular bone cyst of the posterior glenoid that developed after a fracture of the glenoid in a 38-year-old male. The patient had persistent pain, popping and stiffness of his right shoulder for 3 years, and failed to improve after a nonoperative rehabilitation program. At arthroscopy, the senior author transported an autogenous bone graft from the bare area of the humeral head to fill the glenoid cyst arthroscopically. At second-look arthroscopy approximately 1 year after the index procedure, the bone graft had consolidated within the original cystic defect and the surface was covered with fibrocartilage. The graft harvest site posteriorly on the humeral head had healed with a small amount of scar tissue at the articular margin. Comfortable motion and function were restored. 相似文献
1000.
In papillary thyroid carcinoma lymphnode metastases at presentation do not seem to adversely affect survival, but do increase the risk of loco-regional tumor recurrence. The value of systematic versus selective lymphadenectomy is far less standardized, whereas the role of postoperative radioiodine in preventing either nodal recurrence or cancer death remains controversial. Clinical data of 36 N+ patients with papillary thyroid carcinoma who had undergone from 1990 to 1996 ipsilateral or bilateral neck dissection were retrospectively reviewed, to analyse the value of systematic lymphadenectomy. In our series of 50 extensive lymph node dissections (levels 2-6), the number of metastases in each specimen (mean value: 5) and the incidence of multiple level metastases (36%) were high. In 37.5% of the metastases at level 6 and in 11.1% at level 4, coexisting nodal involvement at level 2 was observed, without metastasization at intermediate levels. Multiple levels metastases and skip metastases were present in at least one third of the patients and could be excised only performing a complete dissection of the levels 2-6. Extra-capsular spread was found in 56% of the specimens. In 64.3% of these cases a functional neck dissection was performed. A modified radical or radical neck dissection was carried out in the other 35.7% of the cases. These patients received modified radical neck dissection (functional dissection with sacrifice of internal jugular vein) in 60% of the cases and radical neck dissection in the other 40%. In papillary thyroid carcinoma extensive lymphnode dissection at presentation has been stated to offer no advantage versus selective lymphadenectomy, causing increased morbidity. However, experienced surgeons report a low incidence (less than 5%) of accessory spinal nerve and cervical plexus permanent sequelae after functional neck dissection. In our opinion, patients with cervical lymph node metastases require a complete loco-regional neck dissection. Systematic lymphadenectomy, performed by lateral neck plus upper anterior mediastinal dissection, can yield a high disease-free survival. Moreover, this can limit the overall radio-iodine therapeutic dose and the risk of de-differentiation of recurrent tumor to the anaplastic type in patients with a long-term and near normal life-span. 相似文献