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51.
The capillary white blood cell count and differential, a test easily done in office practice, was used in unexplained febrile illness of infants and toddlers to help distinguish those babies most likely to have bacteremia who would benefit from blood culture and early bacteriologic diagnosis. Four criteria were used as indicators suggestive of bacterial infection: white blood cell count greater than or equal to 15,000/cu mm, total segmented neutrophils greater than or equal to 10,000/cu mm, total band cells greater than or equal to 500/cu mm, and total polymorphonuclear leukocytes (segmented neutrophils plus band cells) greater than or equal to 10,500/cu mm. These measurements were found helpful in separating a small group of bacteremic babies at high risk of complications from a large group of babies who recovered without antibiotic treatment and without complications. There were 146 febrile illnesses recorded in babies 3 to 24 months of age; bacteremia was proven in eight of these. Three or four blood cell count criteria were fulfilled in seven of the eight bacteremic babies and in only ten (7.2%) of the remaining 138 febrile illnesses (P < .001 by chi 2 test).  相似文献   
52.
The cell-free rumen fluid from cattle fed hay or grain exhibited the following biological characteristics which strongly suggest the presence of endotoxin or a toxic principle similar to endotoxin of gram-negative bacteria: proved lethal to mice when injected with actinomycin D; proved extremely lethal to chick embryo; induced biphasic pyogenic response in rabbits; enhanced susceptibility to bacterial infection in mice; evoked positive epinephrine skin reaction in rabbits and phenol-water or aqueous ether proved lethal to mice and chick embryos. A quantitative difference in concentrations of endotoxin was observed on LD50 in mice and chick embryos and response to the epinephrine skin test in rabbits. Cell-free rumen fluid of grain-fed cattle contained at least twice as much endotoxin as that of hay-fed cattle. Endotoxin in cell-free rumen fluid and in higher concentration in cattle fed grain than in those fed hay support the hypothesis that rumen bacterial endotoxins may participate in the pathogenesis of diseases associated with high grain feeding such as lactic acidosis and the sudden-death syndrome.  相似文献   
53.
The influence of 0, 50, 500 or 5,000 ppm supplemental Zn on productive characteristics, weight change, and serum and organ mineral concentrations of 60 crossbred and purebred Yorkshire gilts was evaluated. Gilts were fed their respective treatment from 30 kg body weight until the completion of two parities. Sows fed 5,000 ppm supplemental Zn weighed significantly less than sows from the other treatments when killed. Serum alkaline phosphatase activity was higher for the sows fed the highest level of Zn in all replications at 10 and 14 mo of age than for sows from the other treatments. Sows fed 0, 50 or 500 ppm had lower serum Zn and higher serum Cu concentrations than sows fed 5,000 ppm Zn at 10 and 14 mo of age. The number of pigs farrowed (total and live) and birth weight were not affected by dam's dietary treatment. However, sows receiving no additional Zn had a higher number of abnormal pigs/litter than sows on the other treatments. Sows fed 5,000 ppm additional Zn weaned fewer pigs that weighed less at weaning than sows on the other treatments. The concentration of Zn in the sow's liver increased significantly and liver Cu decreased as dietary level of Zn increased. Sows receiving 5,000 ppm Zn had lower hepatic Fe stores compared with sows receiving 500 ppm Zn. Elevated renal Cu and Zn concentrations were found in sows fed the highest level of Zn supplementation. The Zn concentration was higher and the Cu concentration lower in the aorta of sows fed 5,000 ppm Zn compared with sows fed 0 or 50 ppm additional Zn. Incidence of osteochondrosis was higher in sows supplemented with 5,000 ppm Zn than for sows from the other treatments.  相似文献   
54.
PURPOSE: The authors performed a prospective evaluation of the efficacy of treating ocular cicatricial pemphigoid (OCP) with subconjunctival mitomycin C. DESIGN: Unmasked, prospective, internally controlled case series. METHODS: Patients were eligible for treatment with subconjunctival mitomycin C under three criteria: (1) significant complications of systemic immunosuppressant therapy; (2) markedly asymmetric conjunctival disease; and (3) end-stage OCP. All patients received monocular subconjunctival injections of 0.25 ml of 0.2 mg/ml mitomycin C to both the superior and inferior bulbar conjunctivae in the eye with the more severe disease. RESULTS: Nine eyes of nine patients (mean age, 74 years) were treated with subconjunctival mitomycin C to the more-involved eye and were followed for a mean of 23.5 months (range, 12-40 months). Eight of nine patients showed quiescence of their OCP in the treated eye based on serial evaluation of conjunctival cicatrization and grading of conjunctival erythema. Five of the nine untreated eyes showed progression of the conjunctival disease. One patient required concomitant systemic immunosuppressive therapy after subconjunctival mitomycin C. Two patients underwent successful visual rehabilitative surgery in the mitomycin C-treated eye. CONCLUSION: The use of subconjunctival mitomycin C may be effective in preventing progression of conjunctival cicatrization and erythema in patients with OCP. No complications of mitomycin C treatment were noted. Long-term follow-up and further investigation into the efficacy of subconjunctival mitomycin C in the management of OCP is warranted.  相似文献   
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The objective of this study was to validate retrospective caregiver interviews for diagnosing major causes of severe neonatal illness and death. A convenience sample of 149 infants aged < 28 days with one or more suspected diagnoses of interest (low birthweight/severe malnutrition, preterm birth, birth asphyxia, birth trauma, neonatal tetanus, pneumonia, meningitis, septicaemia, diarrhoea, congenital malformation or injury) was taken from patients admitted to two hospitals in Dhaka, Bangladesh. Study paediatricians performed a standardised history and physical examination and ordered laboratory and radiographic tests according to study criteria. With a median interval of 64.5 days after death or hospital discharge, caregivers of 118 (79%) infants were interviewed about their child's illness. Using reference diagnoses based on predefined clinical and laboratory criteria, the sensitivity and specificity of particular combinations of signs (algorithms) reported by the caregivers were ascertained. Sufficient numbers of children with five reference standard diagnoses were studied to validate caregiver reports. Algorithms with sensitivity and specificity > 80% were identified for neonatal tetanus, low birthweight/severe malnutrition and preterm delivery. Algorithms with specificities > 80% for birth asphyxia and pneumonia had sensitivities < 70%, or alternatively had high sensitivity with lower specificity. In settings with limited access to medical care, retrospective caregiver interviews provide a valid means of diagnosing several of the most common causes of severe neonatal illness and death.  相似文献   
57.
OBJECTIVE: The purpose of this study is to determine the efficacy of initial trabeculotomy in the patient with aniridic glaucoma. DESIGN: Clinical charts were reviewed. PARTICIPANTS: Twenty-nine eyes of 16 patients with aniridia were studied. INTERVENTION: Glaucoma surgery was performed. As an initial procedure, trabeculotomy was performed in 12 eyes, other surgery was performed in 17 eyes (trabeculectomy, 5; goniotomy, 5; other, 7). MAIN OUTCOME MEASURES: Success was defined as an intraocular pressure (IOP) of 21 mmHg or lower, and no further surgery was performed. RESULTS: Ten (83%) of 12 eyes obtained IOP control after first (6 eyes) or second (4 eyes) trabeculotomy with a mean follow-up period of 9.5 years. Five eyes maintained visual acuity of 20/40 to 20/200. No serious complications were found after trabeculotomy. Three (18%) of 17 eyes were controlled with the first glaucoma surgery other than trabeculotomy (goniotomy, trabeculectomy, trabeculectomy combined with trabeculotomy, and Molteno implant). Good IOP control was obtained in 8 (47%) of 17 eyes after several surgeries with a mean follow-up period of 10.4 years. Four of 17 eyes became phthisical. CONCLUSION: This study suggests that trabeculotomy is the preferred initial operation for uncontrolled glaucoma with aniridia.  相似文献   
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59.
Evidence is rapidly emerging which suggests that uncoupling protein 2 (UCP2), by virtue of its ubiquitous expression, may be important for determining basal metabolic rate. To assess the functional modulation of UCP2 gene expression in relation to body weight control, we examined the effects of hyperthyroid state induced by chronic treatment with triiodothyronine (T3) on UCP2 mRNA expression in male rats. Daily subcutaneous injection of T3 (37 pmol/100 g body weight) for 7 days increased UCP2 mRNA expression in brown adipose tissue (BAT), white adipose tissue (WAT) and the soleus muscle 1.6-, 1.6- and 1.7-fold compared to the controls, respectively, and increased UCP1 mRNA expression in BAT 1.2-fold. In contrast, the same treatment with T3 decreased both ob mRNA expression in WAT and plasma leptin level 0.5-fold for each. The present results suggest that T3 may directly increase UCP2 expression independently of leptin action.  相似文献   
60.
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