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991.
Amino acid compositions (AAC) of proteins were analyzed in terms of their uniqueness and variability. Using several measures of convergence between the AACs of randomly chosen proteins versus those stored in protein data banks, it was established that certain families of proteins have unique AACs despite the mutations of their sequences which were imposed in the process of evolution. AACs may be used to establish the identities of many proteins which were sorted through various chromatographic media prior to their fractionation on two-dimensional (2D) gels. Subfractionations of proteins markedly enhance the chances for proper identification of low-abundant proteins which rest inaccessible if the total protein extract of an organ is analyzed on 2D gels. Although the amino acid composition versus protein identity (AAC-PI) method allows identification with high confidence of unique proteins resolved on monodimensional SDS-PAGE (1D) gels and arrays of protein isoforms resolved on two-dimensional (2D) gels, selective immunoblotting is still a more robust method. Thus, in principle, the AAC-PI method may allow limiting the number of "unknown" spots on 2D gels which could be further investigated by microsequencing and/or mass spectroscopy. However, to resolve certain ambiguities inherently linked with protein identities derived only from their AACs, the AAC-PI method must be sometimes aided by microsequencing and immunoblotting, especially in the construction of high-resolution 2D maps of proteins. A suite of algorithms which form the AAC-PI method are described in detail.  相似文献   
992.
The prevalence of genital human papillomavirus (HPV) infection was evaluated in 30 consecutive human immunodeficiency virus (HIV) + women by polymerase chain reaction (PCR)-in situ hybridization (ISH) on paraffin-embedded tissue sections and compared with that found with standard ISH. Biopsies were removed from normal or neoplastic areas in the cervix, vagina, and vulva, and ISH was performed with biotinylated or fluorescein isothiocyanate genomic DNA probes. One probe was used for HPV screening and others for HPV typing (types 6, 11, 16, 18, 31, and 33). Sequences were amplified by the "hot-start" PCR method and followed by standard ISH. Among the 30 HIV + women, 90% scored HPV + in one or several locations by PCR-ISH, whereas only 67% were positive by ISH. Oncogenic HPV types were found in 63% by PCR-ISH and in only 43% by ISH. The same HPV types detected by standard ISH were also recognized by PCR-ISH, but with the latter the signal was amplified. Moreover, some HPV types were found with PCR-ISH but not by ISH. We conclude that PCR-ISH is a valuable and sensitive method for specific detection of HPV.  相似文献   
993.
This is a retrospective review of 101 patients with unknown primary carcinoma (UPC) treated between 1989 and 1994, on whom data were collected prospectively. 92 patients received platinum-based chemotherapy and 9 had single agent 5-fluorouracil (5-FU). In the platinum group, an objective response rate of 37.2% was seen, with a median duration of 4.5 months (range 1.9-17.5). There were no responses with 5-FU alone, while median survival was 6.4 months and was not different from the platinum group (P = 0.09). Considerable symptomatic resolution was noted, although the contribution of chemotherapy alone to this is difficult to define. The impact of tumour response on quality of life and survival in UPC requires further elucidation in prospective studies with a "best supportive care' arm. The superiority of platinum-based treatments reported in selected subgroups cannot be applied to the whole spectrum of UPC.  相似文献   
994.
The Council on Quality and Leadership in Supports for People With Disabilities (The Council), formerly known as The Accreditation Council, altered its definition of quality from "compliance with organizational process" to "responsiveness to people." Council representatives conducted focus group and individual meetings with people who have disabilities to identify priority outcomes they expect from services and supports. The 1993 Outcome Based Performance Measures was used in 447 interviews as part of 54 accreditation reviews. Staff analysis and factor analysis of the outcome interviews using a principle components extraction and varimax rotation resulted in 24 variables loading onto seven major factors (Identity, Autonomy, Affiliation, Attainment, Rights, Health, and Safeguards), which form the basis of The Council 1997 Personal Outcome Measures.  相似文献   
995.
Previous research on race differences in health, we believe, has failed to take into account the initial state of health of the respondents. Other research has demonstrated that elders in poor health are more likely to experience a change in their health over time. It is unclear if the greater probability of decline in health observed among African Americans is a result of being more likely to begin such observations in health states that are worse than those for Whites. This investigation examines declines in health over a 30-month period in a sample of African American and White elders who began the study in similar "good health." Findings support the supposition that African Americans are more likely to report a decline in their health, regardless of the health measure used. Differences by race in the decline of health appear to be a consequence of economic and educational discrepancies between the two groups.  相似文献   
996.
The localisations of bone cysts known under the title of "intraosseous ganglion, synovial cyst of bone and solitary unicameral cyst" are summarised from the literature. Two of the authors' patients are added to the few cases of talar cysts recorded up to the present. In addition, a patient with a calcaneal cyst is described. The cysts can be traumatic or non-traumatic in origin. The various theories concerning their etiology are discussed. The clinical findings, differential diagnosis and therapy of subchondral bone cysts particularly in the region of the foot are considered.  相似文献   
997.
Gentamicin sulfate ophthalmic solution, 0.3%, was used ototopically in the treatment of 300 patients with otorrhea associated with acute and chronic ear conditions and to obtain a preoperative "dry state" in 93 cases in which surgical operation was indicated. Bacterial cultures, antibiograms, and audiometric tests were conducted before, during, and after ototopical therapy. Gentamicin-susceptible pathogens were isolated in all cases. A totally "dry state", after three weeks of therapy, was considered evidence of clinical success. Administration of gentamicin was by means of a wick or at the rate of 0.3 to 0.4 ml twice daily. Clinical success was observed in 271 cases. There were no signs of ototoxicity and only one reported instance of skin reaction. This simple, inexpensive treatment is particularly adaptable to situations in which specialized bacteriological testing facilities are unavailable and a broad-spectrum antibiotic is indicated.  相似文献   
998.
The effectiveness of a short-term fluorouracil chemopophylaxis regimen commencing four to six weeks after "curative" surgery was evaluated in a homogeneous group of 213 patients with colorectal cancer. In stage III disease (Dukes class C), five-year survival with no evidence of disease (NED) was 24.3% when treated by surgery alone but was 57.5% when a prophylactic regimen of fluorouracil was added (P less than .01), an increase of 33.2%. In stage II disease (Dukes class B), five-year NED survival was raised from 58.5% to 81.6%, an increase of 23.1% (P less than .02). More striking are the one-, two-, and three-year NED survivals in stage III. The one-, two-m and three-year NED survivals for the chemoprophylaxis group are 100%, 95%, and 75%, respectively, in contrast to 70.7%, 48.8%, and 34.1% in the group with surgery alone. The present data indicate that fluorouracil chemoprophylaxis offers a significant improvement of five-year cure rate of patients with stage II and III disease, an overall increase of 28.1% (P less than .01).  相似文献   
999.
The value of pulmonary haemodynamic tests during physical exercise in chronic bronchitis was shown by the comparison of two groups of patients. In the first group (n=24) the PAP during exercise is lower than 30 torr. In the second it was over 30 torr. The PAP at rest was always lower than 20 torr. The load was 40 to 50 watts, i.e. an average O2 consumption of 500-600 ml.mm-1 m-2. The cardiac output doubled on average in exercise. Both groups varied markedly in their PAP at rest: 13.6 +/- 1.7 torr for the first group and 15.8 +/- 2.4 for the second (p less than 0.001). In fact differences in pressure during exercise (I=25.0 +/- 3.4 torr; II=39.6 +/- 7.4 torr, p less than 0.001) could be explained mainly by the differences of pulmonary vascular resistances (I=0.91 +/- 0.37; II=1.47 +/- 0.61, p less than 0.005): they tended to fall during effort in the first group and increased slightly in the second; and by the much higher increase in the pulmonary "capillary" pressure during exercise in the second group (I=12.5 +/- 4.4 torr; II=19.7 +/- 72 torr, p less than 0.001). The cardiac output during rest and exercise was equal in both groups. The haemo-dynamic "recovery delay" was much higher in the second group. The spirographic shortage was on the whole identical in both groups. PaO2 on average was higher in group I (p less than 0.05) where it improved during exercise (p less than 0.01). The PaO2 of the second group did improve during exercise. The haemodynamic differences were concomitant with the differences in gas exchanges during effort, of well known prognostic significance. As the "foretelling" of PAP in effort from the PAP at rest was quite poor, it appeared that haemodynamic test in effort has a real value in contributing efficiently to the differenciation of the degree in severeness. The threshold of 30 torr for PAP in exercise (and for the load mentioned above) seemed a good discriminating factor.  相似文献   
1000.
To determine whether family, peer, and school variables are associated with divergent heroin-use patterns or career outcomes, we interviewed 183 black male heroin addicts, experimenters, and non-heroin users from Chicago's south side. While subgroup differences on socio-familial variables generally were not statistically significant, we did observe a number of trends in the expected direction. For example, addicts were more likely than experimenters or nonusers to come from broken homes, to have friends who were involved in serious types of drug use and other illegal activities, and to drop out of high school. At the same time, the pervasiveness of some of our measures of "social disharmony" across the sample suggest that, at least in some inner-city black neighborhoods, these patterns are perhaps becoming the norm.  相似文献   
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