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991.
Bulk tank milk samples from 1070 dairy herds in England and Wales were tested by ELISA for antibodies to bovine virus diarrhoea virus (BVDV). A subset of 341 herds was tested by ELISA for antibodies to bovine herpesvirus 1 (BHV-1), bovine respiratory syncytial virus (BRSV) and bovine coronavirus (BCV). None of the herds had less than 40 dairy cows and none had been vaccinated against BVDV. The prevalence of BVDV antibody-positive herds in the national population was estimated at 95 per cent and approximately 65 per cent of the herds had a high level of bulk tank antibody suggestive of recent infection with BVDV. Dairy herds in East Anglia and the south-east of England had a significantly lower risk of being BVDV antibody-positive than herds in the rest of England and Wales. However, these regional differences tended to diminish with increasing herd size. Around 69 per cent of the herds were BHV-1 antibody-positive and all the herds were antibody positive to BRSV and BCV. Comparison with earlier serological surveys revealed that there had been little change in the prevalence and distribution of BVDV antibody-positive herds in England and Wales over the last 20 years, but that there had been an increase in the prevalence of BHV-1 antibody-positive herds.  相似文献   
992.
After more than 20 years of using ultrasound to examine the fetal head, there are still areas of controversy. The size of the ventricular atrium or the anteroposterior measurement of the posterior fossa have been shown to be relatively stable throughout pregnancy. However, there are instances in which intracranial malformations occur with normal ventricular atrial measurements. Although there are more obvious posterior fossa defects such as Dandy-Walker malformation, there are other abnormalities such as Dandy-Walker variant that are difficult to detect. Another area of controversy surrounds dealing with the fetus with a choroid plexus cyst. Review and understanding of the current literature are needed to best manage these fetuses with choroid plexus cysts. Knowledge of central nervous system embryology and of technical pitfalls of sonography, and understanding the overlap between normal and abnormal anatomy are needed to obtain a more precise central nervous system diagnosis. This article will review some of the borderlines in examination of the fetal brain.  相似文献   
993.
The activity of morantel citrate (5.94 mg/kg base) was determined in laboratory tests against field isolates of benzimidazole-resistant nematodes. Its efficacies against adult and seven-day-old worms were 100 per cent and 100 per cent for Cooperia curticei, 95.1 per cent and 69.8 per cent for Haemonchus contortus and 100 per cent and 82 per cent for Ostertagia circumcincta. Morantel citrate was 100 per cent effective against benzimidazole-susceptible Nematodirus battus and Trichostrongylus vitrinus, and it reduced faecal egg counts by 97.9 per cent in sheep infected naturally with benzimidazole-resistant H contortus and O circumcincta.  相似文献   
994.
BACKGROUND: In the current environment of increasing health care efficiency, the benefits of patient self-history questionnaires need to be fully explored. The utility and reliability of new-patient self-history questionnaires have been documented in the medical literature. This study investigates the prevalence of these patient self-history forms in primary care offices. METHODS: A sample of primary care offices listed in the yellow pages by specialty were surveyed by telephone. Survey questions included the use of new-patient self-history questionnaires as well as other characteristics about the offices. Findings from offices using questionnaires were compared with findings from offices not using questionnaires. RESULTS: Of 129 offices contacted by telephone, 116 (90 percent) responded. Of the 116 offices surveyed, 53 percent were using new-patient self-history questionnaires. Offices using questionnaires had more patients in managed care (P = 0.028) and fewer patients insured by Medicare or Medicaid (P = 0.002). There were no significant differences in other office characteristics. CONCLUSIONS: This study shows that primary care offices underutilize new-patient self-history questionnaires.  相似文献   
995.
Inflammatory pseudotumors of the liver are rare, and their natural history is mostly unknown. Making the diagnosis is often difficult, and these masses are often confused with other lesions, generally either primary or secondary neoplasms. The case of a patient who had an exhaustive preoperative work-up, including ultrasonography, CT scan and MRI, is herein presented. The characteristics of each exam, particularly those of the MRI, in which the pattern is poorly described in the literature, are reported. A fine needle biopsy was not contributive, as it was performed too centrally within the nodule. Only a high degree of suspicion and the existence of this tumor might lead to a preoperative diagnosis, thus avoiding major surgery. However, as is evident from the experiences of most authors and from our own, doubt may persist even after an exhaustive work-up. Since the morbidity and mortality of liver resection of noncirrhotic livers is low, surgery should be considered the treatment of choice.  相似文献   
996.
PURPOSE: This study was undertaken to compare functional results, complications, preoperative durations of disease, and rates of dysplasia and neoplasia between older and younger chronic ulcerative colitis patients undergoing restorative proctocolectomy (RPC) with mucosectomy. METHODS: A total of 392 patients with a preoperative diagnosis of chronic ulcerative colitis underwent elective RPC with mucosection and handsewn ileoanal anastomosis. Pathologic reports were reviewed, with specific reference to findings of dysplasia or cancer. Functional results concerning the number of bowel movements per 24 hour period and the incidence of fecal soilage were obtained by direct or telephone patient interview. FINDINGS: Group I consisted of 326 patients aged 5 to 49 (mean, 30.9) years and 160 women. Group II comprised 66 patients aged 50 to 74 (mean, 56.9) years and 29 women. Duration of disease was significantly longer in the older group (6.2 vs. 15.6 years; P < 0.001). The older group had significantly higher rates of dysplasia (29/326 vs. 19/66; P < 0.0001) and malignancy (14/326 vs. 9/66; P = 0.003). Rates of complication, hospital days following RPC, and total hospital days for all causes were comparable between groups. Perfect day-time continence was observed in 81.6 percent of Group I and 80 percent of Group II patients (213/261 vs. 40/50; P = 0.79). Perfect continence during sleep was observed in 65.1 percent of Group I and 62 percent of Group II patients (170/261 vs. 31/50; P = 0.67). Mean number of bowel movements per 24 hour period for Group I was 6.3 +/- 0.2 and for Group II was 7.4 +/- 0.5. Mean difference, one movement per 24 hours, was not significant (95 percent confidence interval, -0.02 to 2.1; t = 1.95, P = 0.055). CONCLUSIONS: We conclude that patients older than 50 years are suitable candidates for RPC with mucosectomy. Functional results and complication rates are similar to those observed among younger patients. Patients older than 50 years have a significantly higher rate of concurrent dysplasia and malignant degeneration than younger patients, most probably because of a longer duration of disease. RPC with mucosal excision potentially lowers this risk by elimination of all colorectal mucosa.  相似文献   
997.
OBJECTIVE: Evaluation of maternal serum screening for Down's syndrome (DS) and neural tube defects (NTDs). DESIGN: Longitudinal study. SETTING: Department of Obstetrics and Gynaecology, University Hospital Utrecht, the Netherlands. METHOD: 6362 pregnant women underwent serum screening for DS and (or) NTD between the 15th and 21st weeks of pregnancy between March 1991 and March 1996. Screening was performed using alpha-foetoprotein, unconjugated oestriol, human chorionic gonadotrophin and maternal age. The result of each individual test was a calculated risk for delivering a child with DS and (or) NTD. RESULTS: Nine out of 12 singleton pregnancies of a foetus with DS were detected. To this purpose, 573 women who, according to the serum screening had an increased risk of a child with the abnormality, were offered amniocentesis, which was performed in 471 of them. Two twin pregnancies with a total of 3 DS affected foetuses were also detected; one twin pregnancy of a DS foetus was screen-negative. The one case of spina bifida was screen-positive. The proportion of women eligible for invasive prenatal diagnosis because of maternal age increased from 9% to 25% in the course of the study. Of 1118 women aged > or = 36 years 913 (82%) declined invasive investigation compared with 40% in the general population. CONCLUSION: The results of the maternal serum screening program in Utrecht were comparable with other studies. Maternal serum screening is accepted as an alternative by women above 36 years, and allows to decrease the need for amniocentesis without a significant loss in detection rate.  相似文献   
998.
The three dimensional solution structure of the carboxy terminal LIM domain of the avian Cysteine Rich Protein (CRP) has been determined by nuclear magnetic resonance spectroscopy. The domain contains two zinc atoms bound independently in CCHC (C = Cys, H = His) and CCCC modules. Both modules contain two orthogonally-arranged antiparallel beta-sheets, and the CCCC module contains an alpha-helix at its C terminus. The modules pack due to hydrophobic interactions forming a novel global fold. The structure of the C-terminal CCCC module is essentially identical to that observed for the DNA-interactive CCCC modules of the GATA-1 and steroid hormone receptor DNA binding domains, raising the possibility that the LIM motif may have a DNA binding function.  相似文献   
999.
1000.
We see the world as three-dimensional, but because the retinal image is flat, we must derive the third dimension, depth, from two-dimensional cues. Image movement provides one of the most potent cues for depth. For example, the shadow of a contorted wire appears flat when the wire is stationary, but rotating the wire causes motion in the shadow, which suddenly appears three-dimensional. The neural mechanism of this effect, known as 'structure-from-motion', has not been discovered. Here we study cortical area MT, a primate region that is involved in visual motion perception. Two rhesus monkeys were trained to fixate their gaze while viewing two-dimensional projections of transparent, revolving cylinders. These stimuli appear to be three-dimensional, but the surface order perceived (front as opposed to back) tends to reverse spontaneously. These reversals occur because the stimulus does not specify which surface is in front or at the back. Monkeys reported which surface order they perceived after viewing the stimulus. In many of the neurons tested, there was a reproducible change in activity that coincided with reversals of the perceived surface order, even though the stimulus remained identical. This suggests that area MT has a basic role in structure-from-motion perception.  相似文献   
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