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921.
A new treatment program for advanced Hodgkin's disease employing five-drug combination chemotherapy and low dose radiation to the sites of bulk disease (nodal or parenchymal) was designed in 1969. Eighty patients have now been treated, 60 of whom have achieved a complete remission. More significantly, only 5 of the 60 completed responders have relapsed with follow-up from 1-6 years. The cumulative survival at 5 years of patients entering complete remission is 92%. For those patients not sustaining a complete remission, it is 19% at 2 years. This program has resulted in substantially lower relapse rates than previously reported by other investigators, probably because of the administration of radiotherapy in the manner described. Hopefully, a significant number of these patients may be cured of their disease.  相似文献   
922.
Theiler's murine encephalomyelitis virus causes a chronic demyelinating disease in susceptible strains of mice that is similar to human multiple sclerosis. Several nonmajor histocompatibility complex-linked genes have been implicated as determinants of susceptibility or resistance to either demyelination or virus persistence. In this study, we used linkage analysis of major histocompatibility complex identical H-2d (DBA/2J x B10.D2) F2 intercross mice to identify loci associated with susceptibility to virus-induced demyelinating disease. In a 20-cM region on chromosome 14, we identified four markers, D14Mit54, D14Mit60, D14Mit61, and D14Mit90 that are significantly associated with demyelination. Because two peaks were identified, one near D14Mit54 and one near D14Mit90, it is possible that two loci in this region are involved in controlling demyelination.  相似文献   
923.
The roles of gamma interferon (IFN-gamma) and interleukin-12 (IL-12) in mediating and/or enhancing the in vivo trypanosomicidal activity of the nitroheterocyclic derivative benznidazole (Bz) were evaluated during early stages of experimental Chagas' disease. Our results show that treatment of Trypanosoma cruzi-infected mice with anti-cytokine monoclonal antibodies (MAbs) had no apparent effect when the optimal dose of Bz (100 mg/kg of body weight) was used. In contrast, treatment with anti-IL-12 or anti-IFN-gamma MAbs enhanced the parasitemia and accelerated the mortality of mice treated with a suboptimal dose of Bz (25 mg/kg). Simultaneous treatment with a suboptimal dose of Bz and recombinant IL-12 (rIL-12) enhanced the efficacy of drug treatment in terms of parasitemia and mouse survival. Interestingly, we found that drug-resistant T. cruzi strains were found to be poor inducers of IL-12 both in vitro and in vivo compared to strains of T. cruzi which are susceptible or partially resistant to Bz treatment. These results suggest that early activation of the cellular compartment of the immune system by IL-12 may favor in vivo Bz activity against T. cruzi. In order to test this hypothesis mice infected with the drug-resistant Colombiana strain of T. cruzi were treated with 100 mg of Bz per kg plus different concentrations of rIL-12. By using the results of PCR and serological and parasitological methods as the criteria of a cure, our results indicate that a higher percentage of mice treated with Bz combined with rIL-12 than mice treated with Bz alone are cured.  相似文献   
924.
The authors analyzed the thickness of the pyloric muscle of 139 patients with peptic ulcer or gastric cancer. Subtracting the muscular thickness of pylorus measured by a ruler from the thickness estimated by the formula, P.T.=0.0415 X W+2.9, where P.T. represents the thickness of the pyloric muscle in millimeters and W represents the weight of the body in kilograms, they had the deviation from normal, in mm. The muscles with deviations greater than 3 mm were considered hypertrophics. Comparing their material with those of Horwitz et al the authors observed a difference in the group of patients with duodenal ulcer without stenosis in which they obtained 16.5% cases with muscular hypertrophy. Surprisingly, those patients showed positivity of sorologic reactions to Chagas' disease in 83.3% of the cases. These results together with the work of Kunze which demonstrated in 1973 that Chagas' disease may be one of the causative factors of the pyloric muscular hypertrophy, make the authors attribute to the neurological disturbances caused by the American Tripanosomiasis the difference observed.  相似文献   
925.
A variety of laser systems are under investigation as potential tools in dentistry. Most of these systems have been shown to be efficacious for soft tissue surgery of the mucous membranes; however, cutting bone and dental hard tissues has only recently been possible. In this report from the University of California at Los Angeles School of Dentistry, a review of laser applications in dentistry is discussed. The utility of a new laser system using an erbium YSGG medium with air water spray to cut soft tissues, bone, enamel and dentin is under investigation and preliminary research findings are presented.  相似文献   
926.
927.
A study was conducted to evaluate the effects of high dietary vitamin A on vitamin E status and performance of growing-finishing pigs fed diets supplemented with varying levels of vitamin E. Treatments consisted of corn-soybean meal-based diets supplemented with retinyl acetate to provide 2,000 or 20,000 IU of vitamin A/kg of diet and with DL-alpha-tocopheryl acetate to provide 0, 15, or 150 IU of added vitamin E/kg in a 2 x 3 factorial arrangement. The trial involved 84 crossbred pigs (26 kg initial BW) allotted to pens of two pigs each (one gilt, one barrow). Serum was obtained from all pigs on d 0, 3, 7, 21, 35, 63, and 77 of the 83- or 90-d feeding period. Tissue samples (liver, leg, and neck muscle, backfat, and leaf fat) were collected from one pig (barrow) in each pen at the end of the feeding period. Average daily gain and gain:feed were .93 kg and .30, respectively, without treatment differences (P > .10). Serum alpha-tocopherol increased linearly (P < .01) by d 3 with increasing level of dietary vitamin E supplementation. High dietary vitamin A resulted in a small decrease (P < .01) in serum alpha-tocopherol on d 3, but serum alpha-tocopherol concentration was not affected (P > .10) on other days. Tissue alpha-tocopherol increased linearly (P < .001) as dietary vitamin E increased in all tissues examined. No consistent evidence was found to indicate that a high level of dietary vitamin A interfered with performance or with blood serum or tissue alpha-tocopherol concentrations in growing-finishing swine.  相似文献   
928.
929.
In the testes homogenates of rats kept on a A-deficient ration and receiving additionally retinyl-acetate (control) and retinoic acid (experiment) the activity of the phospholipases A1 and A2, with 1-acyl-2(1-14C)-oleoyl-SN-glycero-3-galactosidase and acid phosphatase employed as a substrate, was investigated. In the testes of rats receiving retinyl-acetate the activity of the phospholipases A1 and A2 was greatly declining. An addition of retinyl to the testes homogenates of test rats contributed to re-establishing the activity of the phospholipases up to the control level. In the testes of rats receiving retinoic acid a reduced activity of the acid phosphatase and a rise of beta-galactosidase, as compared to their activity in controls was also demonstrable.  相似文献   
930.
The importance of identifying patients with carotid artery stenosis has attained greater significance in light of recent treatment trials of the efficacy of medical and surgical treatment of both symptomatic and asymptomatic carotid stenosis. Doppler and B-mode ultrasonography can accurately diagnose and quantify stenosis at the cervical carotid artery bifurcation. The development of duplex color-flow instruments has enhanced the sensitivity and specificity of this examination. Ultrasonography should be employed as an initial examination to identify patients with carotid artery stenosis and determine whether further evaluation or treatment is necessary.  相似文献   
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