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81.
Storage of human semen samples at ambient temperature for 24 h resulted in a significant loss of sperm motility from a mean 45.1 +/- 1.8% to 13.8 +/- 1.1% (n = 148). This motility loss was associated with a significant increase in the osmolality of the seminal plasma and the induction of peroxidative damage to the spermatozoa. Both of these detrimental changes could be prevented by diluting the original semen sample 1:1 with a citrate-egg yolk, buffer (CYB). In the presence of this extender all aspects of semen quality were efficiently preserved for 24 h, including sperm movement, penetration of a cervical mucus substitute, the acrosome reaction and sperm-oocyte fusion. CYB extension also permitted the use of chemiluminescent tests of leukocyte contamination to be performed on semen samples stored for 24 h at ambient temperatures. As a preservation medium, CYB was found to be superior to alternative formulations lacking citrate and storage at ambient temperatures was preferable to 4 degrees C. Significant improvements in motility retention were also observed when CYB was supplemented with pentoxifylline, although this treatment significantly stimulated peroxidative damage in the spermatozoa. However, if the pentoxifylline was combined with antioxidants then this collateral peroxidative damage could be reduced and the performance of CYB significantly enhanced. These results have implications for the design of diluents permitting the long-term storage and transportation of human semen samples at ambient temperatures.  相似文献   
82.
The levels and subcellular distribution of the interferon-inducible double-stranded RNA-dependent protein kinase PKR have been measured in human Daudi cells and stably transfected mouse NIH 3T3 cells expressing the human protein kinase. Immunofluorescence of intact cells and quantitative immunoblotting of cell extracts indicate that PKR occurs in both the cytoplasm and the cell nucleus, with staining specifically in the nucleolus. The ratio of cytoplasmic to nuclear PKR is approximately 5:1 in control cells; in response to interferon treatment the protein kinase is induced severalfold in the cytoplasm whereas the level in the nucleus does not increase significantly. Analysis of individual transfected cells by confocal microscopy reveals a pattern of distribution of PKR similar to that in Daudi cells, with immunostaining of cytoplasm and nucleoli. Similar results are observed whether cells expressing wild-type PKR or a catalytically inactive mutant form of the kinase are analyzed, but untransfected 3T3 cells are not stained by the antibody used. Two-dimensional isoelectric focusing analysis of PKR in whole cell extracts reveals the presence of multiple forms with different pI values whereas similar analysis of the nuclear fraction indicates only one predominant species with a relatively basic pI. These results suggest that PKR may have a role in the cell nucleus as well as the cytoplasm and that the subcellular distribution of the protein kinase may be related to post-translational modifications.  相似文献   
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1. The conditions which enable highly efficient utilization of [35S]methionine by cultured mammalian cells and the resolution of selectively labelled mitochondrial products are described. 2. Analysis of mitochondria purified from cells labelled in the presence or absence of inhibitors of cytoplasmic (or mitochondrial) protein synthesis indicated that about 5% of the [35S]methionine incorporated into mitochondrial proteins results from synthesis on mitoribosomes. 3. The electrophoretic profile of the detergent-solubilized proteins of mitochondrial isolated from cells which were labelled in the presence of 50 mug/ml emetine was similar to those obtained with extracts prepared by direct solbuilization of the intact cells after incorporation of label. 4. Pulse-labelling studies suggested that the components resolved by electrophoresis and autoradiography under the conditions described, apparently represent discrete and stable end products radiography under the conditions described, apparently represent discrete and stable end products of mitochondrial protein synthesis. No post-synthetic modification or degradation of these products was detected. 5. Erythromycin was found to suppress the synthesis of additional labelled products which were detected in extracts of one cell line, when analysed by procedures which normally detected only mitochondrially synthesized proteins. These additional bands were attributed to the synthetic activity of Mycoplasma.  相似文献   
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We compared the clinical usefulness of serum myoglobin and creatine kinase MB (CK MB) isoenzyme determinations in the early diagnosis of acute myocardial infarction in 109 consecutive patients admitted to a coronary care unit. Of these, 37 patients were diagnosed as having definite infarction, three possible infarction, and 69 no infarction, using World Heath Organisation criteria. Blood samples were taken on admission and two to four hours later, Both CK MB and myoglobin were raised in the initial serum samples in 24 of the 37 patients with definite infarction. In an additional seven patients both CK MB and myoglobin were negative in the first specimen though both were detected in the second sample. In five patients CK MB preceded the appearance of myoglobin while in the remaining patient myoglobin appeared before CK MB. We conclude that the detection of serum myoglobin does not offer any clinical advantage over CK MG as an early indicator of myocardial infarction.  相似文献   
87.
This article (Part II) and the preceding article (Part I) report the development of two clinical staging systems for HIV-infected individuals. The objective of the research reported here (Part II) was to construct a clinical staging system to predict survival in patients with AIDS. We analyzed data from VA Cooperative Study Number 298, a multicenter, double-blind, randomized trial that compared immediate versus deferred zidovudine therapy in HIV-infected individuals. Baseline variables obtained at the onset of AIDS in 204 individuals were tested in univariate Cox regression for their relationship to survival, and those that appeared predictive were examined in multivariable analysis. Based on these analyses, we constructed a new AIDS Clinical Staging System. The system is based on age, CD4+ cell count, type of first AIDS-defining condition, and functional status. The stages of the system were significant predictors of survival (p = 0.0001, log-rank test). In conclusion, valid, simple clinical staging systems for patients with AIDS can be developed based on a few variables that are readily available in clinical settings.  相似文献   
88.
A previous paper in this journal has described the conventional statistical analysis of three databases (Caucasian, Afro-Caribbean and Asians from the Indian subcontinent) where individuals are typed at six short tandem repeat (STR) loci. This paper presents a Bayesian analysis of the same data and the approach is centred on the concept of estimating coancestry coefficients from mixed databases. Posterior distributions for the three databases are presented and the discussed and the consequences of implementing bootstrap estimation procedures are also shown.  相似文献   
89.
The primary objective of the present investigation was to examine adaptive functioning in the families of patients with a wide range of psychiatric disorders. Seven dimensions of family functioning, as measured by the Family Assessment Device (FAD), were compared across families of patients with a schizophrenia spectrum disorder (n = 61), bipolar disorder (n = 60), major depression (n = 111), anxiety disorder (n = 15), eating disorder (n = 26), substance abuse disorder (n = 48), and adjustment disorder (n = 46). Families in each psychiatric group were also compared to a control group of nonclinical families (N = 353). Results indicated that regardless of specific diagnosis, having a family member in an acute phase of a psychiatric illness was a risk factor for poor family functioning compared to the functioning of control families. However, with few exceptions, the type of the patient's psychiatric illness did not predict significant differences in family functioning. Thus, having a family member with a psychiatric illness is a general stressor for families, and family interventions should be considered for most patients who require a psychiatric hospitalization for either the onset of, or an acute exacerbation of, any psychiatric disorder.  相似文献   
90.
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