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181.
182.
BACKGROUND: Many experts have suggested that blunt splenic trauma in patients older than 55 years should not be managed by observation because of supposed increased fragility of the spleen and decreased physiologic reserve in elderly patients. We sought to determine the outcome of nonoperative management of blunt splenic trauma in patients older than 55 years. METHODS: For the years 1994 through 1996, data for patients with splenic injury older than 55 years from seven trauma centers in a single state were reviewed. RESULTS: Blunt splenic trauma occurred in 41 patients older than 55 years. Eight patients were excluded from further analysis because of death from massive associated injuries within 24 hours of admission. The remaining 33 patients (mean age, 72+/-10 years) were divided into two groups: immediate exploration (10 patients) and observation (23 patients). Observation of blunt splenic injury failed in 4 of 23 patients (17%). No patient deaths were related to the method of management of the splenic injury. CONCLUSIONS: Observation of the elderly patient with blunt splenic trauma has an acceptable failure rate of 17%.  相似文献   
183.
The ectromelia virus (EV) has been recognized as the etiological agent of a relatively common infection in laboratory mouse colonies around the world, i.e., Europe (including Poland), USA and Asia. Due to widespread use of mice in biomedical research, it is important to study the biology of strains characteristic for a given country. This is particularly significant for the diagnosis, prevention and control ectromelia. In severe epizootics, approximately 90% morbidity is observed within colonies and mortality rate exceeding 70% is observed within 4 to 20 days from the appearance of clinical symptoms. The resistance to lethal infection is mouse strain-dependent. Several inbred strains of mice, including C57BL/6 and AKR are resistant to the lethal effects of EV infection, while others, such as A and BALB/c are susceptible. Recent studies indicate that (1) T lymphocytes, NK cells and interferon (IFN)-dependent host defenses must operate for the expression of resistance, (2) virus-specific T-cell precursors appear earlier in regional lymph nodes of resistant than susceptible mice, and (3) resistance mechanisms are expressed during early stages of infection. Over the past several years, (1) induction of anti-EV cytotoxic CD8+ T lymphocytes (CTL) responses in vivo in the absence of CD4+ (T helper) cells, (2) importance of some cytokines e.g., IFN-gamma in EV clearance at all stages of infection, and (3) induction of nitric oxide (NO) synthase, which is necessary for a substantial antiviral activity of IFN-gamma, have been demonstrated.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
184.
Surveillance by parental concern has been advocated to assess whether formal child developmental testing is needed. To determine whether alcohol intake or illicit drug use in pregnancy is associated with differences in maternal perception of infant development, mothers with acknowledge alcohol and drug habits during pregnancy (N = 120) were interviewed at 11 months' postpartum, within 1 month before infant testing by use of the Bayley Scales of Infant Development. Women with heavy alcohol intake during pregnancy (> 3.5 oz absolute alcohol per week) were 15-fold more likely to overestimate their infant's mental development (P < 0.05), whereas mothers using illicit drugs were 4-fold more likely to overestimate their infant's physical development (P = 0.02). Given the frequent denial of substance abuse, we suggest that health care providers be cautious in accepting a lack of parental concern about a child's development and rely more heavily on formal testing, particularly in high-risk populations.  相似文献   
185.
The thermal inactivation ofEnterocuccus faeciumin bovine whole milk was studied in a high-temperature short-time pilot scale pasteurizer. Integrated lethal effect, or pasteurization effect (PE), was obtained by converting times at different temperatures in the various sections of the pasteurizer to the equivalent time at the reference temperature (72°C). Survival curves showed distinct tailing, suggesting the presence of a secondary, more heat-resistant population. PE was initially related by a simple linear function to the log10of the percentage viable counts, with a power transformation of the PE values to improve linear fit. Residuals obtained from fitting the power transformation model to the various trials showed considerable systematic deviations, and an improved fit was obtained with a biphasic logistic function. A single model based on average parameter values from pooled data was inadequate, and a random coefficient model was used to incorporate inter-trial variability. The random coefficient model replaces the average predicted value with a distribution of possible outcomes, and yielded superior fits to the data, thus is preferred for prediction.  相似文献   
186.
An investigation is made of the implications that the presence of a Bose condensate (BC) has for the form of the many particle Schröedinger wavefunction. It is shown that many particle wavefunctions of states which contribute to the BC, contain long range structure in the position space of each particle. It follows from the requirement that the wavefunction is single valued that, in the presence of a BC, the angular momentum of each particle must be quantised over macroscopic length scales. The paper thus provides a new and simple proof from first principles, that Bose condensation implies macroscopic quantum behaviour. It is shown that this behaviour can be described in terms of the occupation by each particle of the same single particle-like macroscopic wavefunction. The structure in position space of this wavefunction is investigated, using a well known model of the many particle wavefunction for the ground state of4He. The model predicts that the probability density of each particle is delocalised in the presence of a BC, occupying all spaces in the sample volume, from which the particle is not excluded by the hard core interaction with other particles.  相似文献   
187.
Eight canine tumors originating from specific glandular structures in the anal region, as well as metastatic tumor tissue of two of these cases (case Nos. 7, 8), were immunohistochemically analyzed using various monoclonal antibodies (MoAbs) directed against human keratin types, vimentin, neurofilament proteins, and alpha-smooth muscle actin. These tumors also were stained for the broad-spectrum neuroendocrine markers neuron-specific enolase (NSE) and synaptophysin. In histologically normal canine anal structures, alpha-smooth muscle actin and NSE antibodies stained basally localized (probably myoepithelial) cells in the anal glands and the anal sac glands. NSE staining also was present in a limited number of luminal cells in both anal glands and anal sac glands. Synaptophysin labeling was not observed in any of these glandular structures. Histologically, the tumors were differentiated into well- and moderately differentiated perianal gland tumors (n = 5) and carcinomas without perianal gland differentiation (n = 3), corresponding to the so-called apocrine carcinomas of the anal region. Immunohistochemically, the perianal gland tumors could be differentiated from the carcinomas by marked differences in staining pattern with the various keratin MoAbs, particularly MoAbs directed against human keratin types 7 and 18. The keratin-staining characteristics of the carcinomas suggest a glandular luminal cell origin. Metastases of the carcinomas showed loss of some keratin-staining characteristics as compared with the primary tumor. Staining for NSE was only observed in solitary cells and small cell clusters in the carcinomas and their metastases, whereas the alpha-smooth muscle actin antibody did not react with the carcinoma cells. None of the tumors stained for neurofilament proteins or synaptophysin. An unequivocal neuroendocrine nature of the carcinomas could not be substantiated by our immunohistochemical study, although the presence of a population of neuroendocrine cells within these neoplasms seems likely. Because the immunohistochemical features of the carcinomas with respect to various keratin MoAbs and NSE are similar to those of the anal glands and the anal sac glands, both these glands might be considered as site of origin of these carcinomas.  相似文献   
188.
189.
Effects of grain species and grain processing method on DMI, rate and efficiency of gain, and feeding value for cattle fed high concentrate diets were appraised by statistically compiling results from 605 comparisons from feeding trials published in North American journals and experiment station bulletins since 1974. Metabolizable energy (ME) values for each grain and processing method were calculated by quadratic procedures from DMI and animal performance. Averaged across processing methods, ME values for corn, milo, and wheat grain (3.40, 3.22, and 3.46 Mcal/kg DM) fell within 9% of ME estimates from NRC (1996) for beef cattle. In contrast, ME values for barley and oats grain (3.55 and 3.46 Mcal/kg DM) were 24% and 17% greater than NRC (1996) estimates. Compared with the dry rolled forms, high moisture corn and milo resulted in lower ADG and DMI. Compared with dry rolling, either steam rolling or flaking of corn, milo, and wheat decreased DMI without decreasing ADG and improved feed efficiency by 10, 15, and 10%, respectively. Compared with dry rolled grain, steam flaking increased (P < .05) body weight-adjusted ME of corn and milo grain by 15 and 21%, respectively; body weight-adjusted ME for whole corn was 9% greater (P < .05) than for rolled corn grain. Steam flaking was surprisingly effective (13%) at increasing (P < .05) the body weight-adjusted ME of wheat, but steam flaking failed to increase the ME of barley and oats. Higher moisture content of high-moisture corn decreased dry matter intake without depressing ADG and improved efficiency and increased ME of the grain. Compared with steam flakes of moderate thinness, processing milo or barley to a very thin flake tended to reduce ADG and failed to improve feed efficiency. The ideal roughage source and roughage moisture content for maximum ME and ADG varied with grain processing method. Feeding corn silage rather than alfalfa and wet rather than dry roughage depressed (P < .01) ADG of cattle and reduced (P < .01) body weight-adjusted ME of cattle fed high-moisture corn grain but tended to increase both with steam-flaked corn or wheat.  相似文献   
190.
Pefloxacin, ciprofloxacin and norfloxacin were shown to induce elimination of the virulence plasmids in the strains of Y. pseudotuberculosis. Pefloxacin had a more pronounced eliminating effect than ciprofloxacin and norfloxacin. The elimination of the virulence plasmids with the molecular weight of 40-50 MD in the strains of Y. pseudotuberculosis was more frequent at the subinhibitory concentrations of the fluoroquinolones or at 1/4 of the fluoroquinolone MIC., At 1/8 of the MIC it was rarer. The virulence plasmid elimination in the strains was observed in spite of their serovar but was more frequent in the serovar 1B strains.  相似文献   
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