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281.
The expression of the tumor suppressor/oncoprotein p53 has been investigated in normal human placental villous trophoblast, in vitro propagated invasive extravillous trophoblast, SV40 tumor antigen (Tag)-immortalized extravillous trophoblast, human cytomegalovirus (hCMV)-infected syncytiotrophoblast and malignant trophoblast (choriocarcinoma) cell lines (JAR, JEG-3 and BeWo) using quantitative enzyme-linked immunosorbent assay (ELISA) and Western immunoblot methods using monoclonal antibodies specific for wild-type and mutant p53. The normal villous and extravillous trophoblast cells expressed low levels of the wild-type p53 protein, whereas normal terminally differentiated multinucleated syncytiotrophoblast cells, as well as hCMV-infected syncytiotrophoblast, showed a higher expression of the wild-type p53 protein. SV40 Tag-immortalized invasive trophoblast cells also showed a high expression of the wild-type p53 protein which remained complexed with the Tag protein. All the choriocarcinoma cell lines over expressed the mutant form of the p53 protein. The increased expression of p53 protein in the SV40 Tag-immortalized invasive trophoblast and choriocarcinoma cells paralleled with increased expression of the mouse double minute 2 (mdm2) oncogenic protein. Transforming growth factor (TGF)-beta inhibited proliferation of normal extravillous trophoblast cells. The antiproliferative effects of TGF-beta were reduced in SV40 Tag-immortalized cells and non-detectable in choriocarcinoma cell lines JAR, BeWo and JEG-3. The inactivation of p53 owing to complexing with Tag in the immortalized premalignant trophoblast and p53 mutation in the malignant trophoblast may be responsible for their aberrant proliferation and refractoriness to antiproliferative effects of TGF-beta observed in these cells as compared to the normal trophoblast. These results may suggest the role of p53 protein in trophoblast differentiation, transformation and tumorigenesis.  相似文献   
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Restoring splinted mandibular incisors and canines with full crown restorations has always presented a challenge in creating an esthetic illusion of reality of normal individual teeth. This treatise is designed to present the rules for mandibular anterior esthetics that have been distilled from almost 4 decades of clinical practice of restoring dentitions that have been severely compromised by the deformities of disease or accident. The resultant formula systematically creates the desired results with a high degree of predictability.  相似文献   
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BACKGROUND: The objective of the study was an analysis of results of repeated kidney transplantations (Tx2, Tx3) implemented during the first 29 years of activities of the Transplantation Centre of the Institute of the Clinical and Experimental Medicine in subjects with a different maintenance immunosuppression. METHODS AND RESULTS: The retrospective study pertains to 134 Tx2 and 17 Tx3 in 134 non-diabetic subjects: 43 of them had during Tx1 and Tx2 (1966-1981 and 1966-1985 resp.) immunosuppression on the basis of azathioprin (Aza, sub-group AA), 42 during Tx1 (1972-85), Aza, while during Tx2 (1984-85) immunosuppression on the basis of cyclosporin (CyA, subgroup AC) and 49 both during Tx1 and Tx2 (1985-93 and 1986-95 resp.) CyA (subgroup CC). Compared was survival of grafts by the actuarial method (with regard to all losses regardless of cause) by the end of the 4th year inside the subgroups (Tx2, vs. Tx1 and Tx3 vs. Tx2 in the same subjects) and between subgroups (Tx1 vs. Tx1 and Tx2 vs. Tx2 in different subjects). Moreover in paired investigations the survival of recipients and grafts after Tx2 was compared after immunosuppression on the basis of CyA with the same parameters after Tx1 in different subjects with the same immunosuppression, operated at approximately the same time (n = 81) and survival of subjects with Tx1 + Tx2 on the CC regime regardless whether the second grafts functioned at the time of the last examination, with survival of subjects after Tx1 where after graft failure Tx2 was not performed (n = 34). Prophylaxis with antilymphocyte globulins was not used. Survival of second and first grafts did not differ in any of the subgroups, third grafts survived at the end of the third year more frequently than second grafts (66 vs. 18%, p < 0.01). Second grafts in CC survived more than in AA (55 vs. 28%, p < 0.01). In the paired study Tx2 vs. Tx1 the survival of grafts and recipients was the same (88 vs. 89%, N.S. and 47 vs. 62% resp.), in the paired study Tx1 + Tx2 vs. Tx1 more subjects with Tx1 + Tx2 survived 10 years after Tx1 than subjects who did not have Tx2 (82 vs. 49%, p < 0.05). CONCLUSIONS: A further transplantation of the kidney after functional loss of the first graft is the method of choice: the mortality is low, the probability of several years' function is considerable and the prognosis as regards quality and length of life better than with regular dialysis treatment.  相似文献   
285.
Giant cell (temporal) arteritis continues to be a sight-threatening, systemic vasculitis with a poorly understood pathogenesis. The characteristic granulomatous inflammation of the vessel wall commonly leads to local ischemia. Recent advances in immunological investigations have characterized the cellular components of the disease process, but the etiology has so far remained unresolved. A reappraisal of the clinical features of giant cell (temporal) arteritis demonstrates the heterogeneity of the manifestations of the disease, including ischemic optic neuropathy. A range of new laboratory investigations and blood flow studies with color Doppler imaging have demonstrated promising roles, with respect to diagnosis and long-term follow-up. Prompt diagnosis and expeditious treatment require a high index of clinical suspicion, particularly for atypical cases. Corticosteroids remain the treatment of choice, other immuno-suppressive agents being used as second line steroid-sparing agents. Giant cell (temporal) arteritis leads to increased vascular and visual morbidity and, if untreated, may prove fatal. To maintain high standards of management of this enigmatic disorder, ophthalmologists need to be aware of the clinical spectrum of giant cell (temporal) arteritis and currently available diagnostic tests and treatment strategies.  相似文献   
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PURPOSE: The most devastating complication after the insertion of a penile prosthesis is the development of infection. The standard approach involves removing the entire device, treating intensively with antibiotics and attempting to reinsert a prosthesis at a later date, often with a suboptimal result. Based on the encouraging results of others, during the last 24 months we have used in 2 separate private urological practices a salvage procedure for treatment of infected inflatable penile prostheses. MATERIALS AND METHODS: The protocol used in 7 men with an infected inflatable penile prosthesis included removal of all device components, a 7-step vigorous intraoperative irrigation with 4 different solutions, including vancomycin, immediate reimplantation of a new inflatable penile prosthesis and postoperative outpatient antibiotics with oral ciprofloxacin or intravenous vancomycin or cefazolin. RESULTS: Of the 7 men 6 have experienced excellent results with no infection, minimal morbidity and preservation of penile length. The only failure occurred in a poorly controlled diabetic who required multiple revisions and may have had latent infection for months before it became apparent. CONCLUSIONS: We believe that an immediate salvage procedure for an infected inflatable penile prosthesis is an effective treatment for this difficult complication.  相似文献   
289.
MRI of the liver is a powerful imaging modality for detection and characterization of liver pathology. MRI technology continues to evolve with developments in scanner hardware performance and refinements in imaging sequences, particularly in respect to fast imaging techniques, improving the quality of images that can be routinely achieved. Fast imaging techniques allow dynamic contrast-enhanced scanning to assist in lesion detection and characterization. An array of tissue-specific contrast agents are also becoming available; the clinical utility of some of these agents is yet to be fully established. An overview of scanning technique, contrast media, and the role of MRI in liver lesion detection and characterization is presented, with a review of the typical imaging characteristics of common focal and diffuse hepatic diseases. Where possible, emphasis has been placed on features that allow distinction between the various pathologic entities described.  相似文献   
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Cancer patients (n = 913) who received treatment within the previous 2 years were interviewed to quantify reports of symptoms associated with cancer, measure the impact of symptoms on lifestyles, document experiences with accessing information and treatment for cancer and its symptoms, and record attitudes about the level of care received. Cancer patients were primarily recruited through newspaper ads placed throughout Canada and asked to complete a self-report questionnaire. Patients called a toll-free number and were interviewed to ensure eligibility. Most respondents were female (66%) with breast cancer (64%). Prostate cancer (40%) was the most common diagnosis among males. Almost all respondents (94%) reported experiencing one or more symptoms. Fatigue and anxiety were the most frequently reported symptoms (78% and 77%, respectively). Fatigue was most likely to be self-rated as moderate to severe and was most likely to interfere in normal daily activities. Respondents who experienced fatigue reported a more frequent use of healthcare services (including complementary therapies) than those who did not experience fatigue. Half of the respondents reported trying to find information on fatigue, but only half of these said they had obtained information. The most helpful sources of information were nurses, specialists, and other cancer patients. Respondents were more likely to be dissatisfied with their treatments for their symptoms than for their cancer. This survey indicates that most cancer patients experience symptoms related to the disease and its treatment. The most prevalent symptoms are fatigue and anxiety; fatigue is the most debilitating.  相似文献   
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