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Bone biopsies were studied in 73 patients to determine if a two-site radioimmunometric assay for serum bone alkaline phosphatase (BAP), total serum alkaline phosphatase (ALP), serum intact parathyroid hormone (iPTH), hand X-rays, regional bone mineral density (BMD) measurements and parathyroid enlargement detected by ultrasonography could accurately predict renal osteodystrophy. In the patients studied 57 had hyperparathyroid bone disease, 4 mixed renal osteodystrophy, 3 adynamic bone disease, 1 osteomalacia and 8 normal histology. Serum BAP, ALP and iPTH correlated positively with mineral apposition rate, osteoblastic, osteoid and eroded surface. In the diagnosis of hyperparathyroid bone disease serum iPTH was the most sensitive investigation, detecting 81% of patients at a level > 100 pg/ml but with a specificity of only 66%. Serum BAP was more sensitive, 70% at a level of > 10 ng/ml, than serum total ALP, 30% at a level of 300 IU/l, with similar specificities, 92 and 100%, respectively. Ultrasound detection of an enlarged parathyroid gland had a sensitivity of 64% and a specificity of 100% for the diagnosis of hyperparathyroid bone disease. Hand X-rays had a poor sensitivity, 47%, but a high specificity, 92%, for the detection of hyperparathyroid bone disease. The majority of patients had regional BMD values within the normal reference range and this test was of poor discriminatory value. The non-invasive markers were unable to distinguish between patients with low turnover, mild hyperparathyroidism and patients with normal histology. In conclusion the measurement of serum iPTH is a useful screening tool for the detection of hyperparathyroid bone disease which can be confirmed by the finding of a raised serum BAP or parathyroid enlargement. For definitive diagnosis, however, the gold standard remains bone biopsy and at present one cannot recommend any non-invasive method as an adequate substitute.  相似文献   
3.
A case-mix classification system for medical rehabilitation   总被引:2,自引:0,他引:2  
Dissatisfaction with Medicare's current system of paying for rehabilitation care has led to proposals for a rehabilitation prospective payment system, but first a classification system for rehabilitation patients must be created. Data for 36,980 patients admitted to and discharged from 125 rehabilitation facilities between January 1, 1990, and April 19, 1991, were provided by the Uniform Data System for Medical Rehabilitation. Classification rules were formed using clinical judgment and a recursive partitioning algorithm. The Functional Independence Measure version of the Function Related Groups (FIM-FRGs) uses four predictor variables: diagnosis leading to disability, admission scores for motor and cognitive functional status subscales as measured by the Functional Independence Measure, and patient age. The system contains 53 FRGs and explains 31.3% of the variance in the natural logarithm length of stay for patients in a validation sample. The FIM-FRG classification system is conceptually simple and stable when tested on a validation sample. The classification system contains a manageable number of groups, and may represent a solution to the problem of classifying medical rehabilitation patients for payment, facility planning, and research on the outcomes, quality, and cost of rehabilitation.  相似文献   
4.
Vibrio cholerae causes epidemic diarrhea throughout the world. Fluid replacement is the primary therapy for cholera; however, high mortality rates often necessitate the use of antibiotics. V. cholerae, like most bacteria, has developed resistance to some antibiotics. In the early 1990s a new serotype strain, Bengal 0139, began a new wave of cholera epidemics. Bengal isolates showed unique trends in antimicrobial resistance. Many clinical laboratories use automated antibiotic susceptibility testing for V. cholerae. It is important to know if automated susceptibility test results for V. cholerae coincide with reported trends in antibiotic susceptibility. In the present study, we used the Vitek automated susceptibility system to determine the susceptibilities of 79 V. cholerae O1 isolates, 100 O139 isolates, and 112 non-O1 isolates. Vitek susceptibilities for V. cholerae showed a good correlation with preestablished epidemiological data. Although the new O139 serogroup showed a trend of increased resistance to trimethoprim-sulfamethoxazole and nitrofurantoin, it was more susceptible to ampicillin than previous serogroup O1 and non-O1 strains. Regardless of serogroup, > or = 98% of the V. cholerae isolates tested were susceptible to most antibiotics tested by us. It is important to continue susceptibility testing of all new isolates of V. cholerae because of emerging resistant strains. However, V. cholerae remains susceptible to most of the available antibiotics.  相似文献   
5.
Hyperimmune anti-human immunodeficiency virus immunoglobulin (HIVIG) is an intravenous immunoglobulin prepared from HIV-infected asymptomatic donors with a CD4 cell count greater than 400 cells/microl and a high titer of antibody to HIV-1 p24 protein. Twelve persons with AIDS received four doses of HMG (two at 50 mg/kg of body weight and then two at 200 mg/kg) every 28 days. Pharmacokinetics were evaluated by measurement of anti-p24 antibody. HIVIG was well tolerated, and all participants completed the study. Three subjects who were not receiving Pneumocystis carinii pneumonia (PCP) prophylaxis developed PCP. The mean value for HIVIG clearance was 3.02 ml/kg/day at 50 mg/kg and 3.65 ml/kg/day at 200 mg/kg (P = 0.027); the mean trough antibody titers (reciprocal units) were 1,442 and 4,428, respectively. This study indicates that high titers of anti-p24 antibody can be maintained with a monthly administration schedule of HIVIG and that short-term safety is acceptable. Comparisons to evaluate the therapeutic potential of HIVIG are justified.  相似文献   
6.
Minimally invasive plastic surgery has expanded beyond the original confines of aesthetic applications to encompass all our endeavors in an attempt to restrict the size of surgical scars, limit postoperative discomfort, and hasten recovery of function. This evolution has already delineated methods to raise our workhorse muscle flaps and has negated the risks of laparotomy for various visceral flaps. It is then only a logical progression to use these endoscopic techniques to harvest fascial flaps so as to avoid the notorious donor site morbidity of the fasciocutaneous flap, which has certainly hindered the rapid acceptance of these otherwise valuable flaps. Endoscopic-facilitated elevation of a local adipofascial flap is described for which little or no additional skin incisions need ever be made.  相似文献   
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The effects of sex and age on patterns of circulating somatotropin (ST) concentration and plasma IGF-I, IGF-II, insulin, and IGF binding protein-3 (IGFBP-3) were studied in ram, wether, and ewe lambs (n = 7 or 8) sampled at mean ages of 81 (I1) and 158 d (I2). Between 81 and 158 d of age, rams grew more rapidly than wethers (P < .01), and wethers grew more rapidly than ewes (P < .01). The sex differences in growth were reflected in empty body weight at slaughter: rams > wethers > ewes (P < .05). Mean plasma ST concentrations, ST pulse amplitude, and integrated plasma ST concentrations were greater (P < .05) in rams than in ewes at I1 and I2. Characteristics of the ST plasma profile in wethers were generally intermediate between those of rams and ewes. The interpulse interval was greater in ewes than in wethers at I2. The IGF-I and IGFBP-3 concentrations were greater in rams than in ewes at both sampling times. Plasma IGF-II was greater in ewes than in rams at I2. Mean plasma ST was approximately two thirds less at I2 than at I1 regardless of sex. Mean plasma ST and IGF-I at both ages were positively correlated with growth. Mean plasma ST at I2 was negatively correlated with fatness at slaughter. Sex and age significantly affected patterns of circulating ST and concentrations of IGF-I and IGFBP-3 in prepubertal growing lambs, under conditions for which growth rates and composition were also sexually dimorphic.  相似文献   
9.
Stormwater reuse: designing biofiltration systems for reliable treatment.   总被引:1,自引:0,他引:1  
Stormwater reuse is increasing in popularity as a technique for overcoming water shortages in urban Australia. However, technology for the reliable treatment of stormwater for reuse is still not fully developed. This paper presents the first steps in refining biofilters for stormwater reuse. Six different filter media were selected, to target specific stormwater pollutants, as well as support plant growth. They were tested in the laboratory, where the filters were dosed three times per week with semi-synthetic stormwater for five weeks. Pollutant removal performance was monitored, and revealed that all soil-based filters performed similarly (while sand filters behaved somewhat differently). All filters removed more than 80% of solids and greater than 90% of lead, copper, and zinc. Three filter types were able to remove some phosphorus (particularly in the top 30 cm of the media). Apart from sand, all filter media were net producers of nitrogen, leading to an important conclusion that non-vegetated, soil-based filters are not suitable for targeting nutrients. However, since heavy metals are the primary pollutant of concern with respect to stormwater reuse for irrigation (the most popular end-use), it was concluded that biofilters may be promising technologies for treatment of stormwater for reuse.  相似文献   
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