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31.
Zolpidem, an imidazopyridine that purportedly binds selectively to certain GABA(A) receptor subtypes, is the most commonly prescribed hypnotic. The present article critically reviewed the extant experimental literature to determine whether the behavioral pharmacologic profile of zolpidem also differs from that of benzodiazepines. Specific topics that are reviewed include: 1) reinforcing effects and abuse potential, 2) discriminative-stimulus effects, 3) subject-rated drug effects, 4) performance-impairing effects, 5) tolerance-producing effects, and 6) physiological dependence-producing effects. Studies that employed both nonhumans and humans are reviewed. Based on the available literature, the most parsimonious conclusion is that despite its unique neuropharmacological profile, the behavioral effects of zolpidem are generally similar to those of benzodiazepines. However, it is important to note the dearth of perspective, experimental studies that directly compared zolpidem and a benzodiazepine. Because of the clinical relevance and paucity of published studies, future research should focus explicitly on assessing the reinforcing effects, abuse potential, performance-impairing effects, tolerance-producing effects, and dependence-producing effects of zolpidem relative to a benzodiazepine. Important issues such as the selection of an appropriate comparison drug and subject population, and the doses tested needed to be considered in these future studies.  相似文献   
32.
OBJECTIVE: Our objective was to examine the stability of body habitus over 15 years in Boston area adult males enrolled in the Normative Aging Study (NAS) and to examine stability as a function of initial leanness or obesity, age and reported body habitus at age 18. DESIGN: Prospective observational study of anthropometric/clinical measures initiated in 1961-1970, follow-up examinations at regular three and five year intervals. Subjects with complete data at entry, 5, 10 and 15 years. SUBJECTS: The 2280 Boston area subjects were aged 21-80 years (mean = 42 y) at entry. A subset (n = 350) with complete data for weight (WT) and height (HT) at four points over 15 years provided estimates of body habitus continuity. The prevalence of obesity and age of those studied were comparable to the complete sample of enrolled men (n = 1403) with any missing follow-up measures. MEASUREMENTS: Obesity was defined as body mass index (BMI) (weight in kg/height in m2) > or = 27.8 and leanness as BMI < 24.0. Three age categories at baseline (young = 25-39 y; middle = 40-49 y and old = 50-74 y) were used to examine secular and longitudinal changes. Obesity prevalence rates during late adolescence, based on self-reported weights at age 18, were compared with measured prevalence rates at entry and follow-up. Individual changes in BMI over time for each subject were estimated by linear regression and were combined to measure change in age and BMI groups. RESULTS: Weights and BMI at entry were highly correlated with 18 year values and 15 year follow-up values. New cases of obesity, defined on the basis of BMI, increased over time while the numbers of subjects classified as lean and intermediate decreased. Among oldest subjects both the lean and obese had slight but significant decreases in mean BMI. Among the lean, only the young showed consistent increments. DISCUSSION: Our results suggest consistency in body habitus among young and middle-aged obese subjects. There was little evidence of long-term reduction. In agreement with previous observations, the current findings of long-term duration in obesity suggest that preventive efforts should be focused on early years.  相似文献   
33.
Oxytocin analogues which combine high oxytocic activities with negligible antidiuretic and pressor activities have been studied. [4-Threonine,7-glycine]oxytocin, [1-(L-2-hydroxy-3-mercaptopropionic acid),4-threonine,7-glycine]oxytocin, and [1-(L-2-hydroxy-3-mercaptopropionic acid)]oxytocin were found to possess the following specific biological activities respectively: rat uterotonic, 270 +/- 10, 337 +/- 23, 1542 +/- 0.4; rat antidiuretic, 0.002 +/- 0.0008, 0.048 +/- 0.005, 40.3 +/- 2.4. The results are analyzed from a conformation-activity viewpoint in a continued attempt to evaluate the scope and limitations of this approach in comparison to structure-activity studies.  相似文献   
34.
The APA Insurance Trust is pleased to announce the establishment of a new Group Life Insurance Program for APA members and their families. The new program represents more than a year of intensive investigation and many months of negotiation with leading insurance carriers. A few highlights of the program are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The reported relapse-free survival for women with invasive breast cancers measuring no more than 10 mm in dimension ranges from 75% to 95%, with axillary status an important prognostic factor in most series. Further study of prognostic variables in this most favorable subset is notably limited. We retrospectively reviewed the records of 168 women with invasive breast cancers < or = 10 mm treated with either breast conserving surgery+axillary dissection (AXD) and radiation therapy, or mastectomy+AXD. The actuarial survival and survival free of distant metastases (DMFS) at 7 years was 95% and 97%, respectively. Location and size of the primary tumor were most important in predicting outcome, although statistical significance was not achieved. The 5-year distant metastases-free survival (DMFS) was 100% for central and inner quadrant tumors, compared to 97% in those with outer quadrant tumors, p = 0.18. The 5-year DMFS was 100%, 95%, and 98% for patients with cancers 2-5 mm, 6-9 mm, and 10 mm, respectively, p = 0.15. Status of the axillary lymph nodes, type of breast surgery, clinical tumor status (palpable vs. nonpalpable), age, menopausal status, histologic grade, systemic therapy, or histologic type were not found to have a significant impact on prognosis.  相似文献   
38.
The Depression Guideline Panel of the Agency for Health Care Policy and Research in 1993 published recommendations for treating major depression in primary care practice that were often based on studies of tertiary care psychiatric patients. We reviewed reports of randomized controlled trials in primary care settings published between 1992 and 1998. This evidence indicates that both antidepressant pharmacotherapy and time-limited depression-targeted psychotherapies are efficacious when transferred from psychiatric to primary care settings. In most cases, the choice between these treatments should depend on patient preference. Studies to date suggest that improving treatment of depression in primary care requires properly organized treatment programs, regular patient follow-up, monitoring of treatment adherence, and a prominent role for the mental health specialist as educator, consultant, and clinician for the more severely ill. Future research should focus on how guidelines are best implemented in routine practice, since conventional dissemination strategies have little impact.  相似文献   
39.
We compare the chemical profiles of Cr, Mn, Si and Se with the electron concentration profiles in Si, Se and S implanted semi-insulating Cr-O doped bulk GaAs substrates and undoped VPE buffer layers annealed with and without a SiO2 encapsulant in a H2-As4 atmosphere. A higher activation efficiency in the net electron concentration and the gateless saturated channel current is measured for SiO2 encapsulated wafers annealed under arsine overpressure than for capless annealed ones using Cr-O doped bulk GaAs substrates. On the other hand, the net donor concentration peak is higher for implanted buffer epi layers capless annealed under arsine overpressure than for SiO2 encapsulated ones. Secondary ion mass spectrometry (SIMS) studies of the Cr decoration of the implant damage indicate that the damage from the 100 keV Si implant anneals out at 840°C while a temperature of 900°C is required to anneal out the 260 keV Se implant damage. An explanation of these differences is provided using an impurity redistribution model and charge neutrality considerations. Excellent Hall electron mobilities at liquid nitrogen temperature of 5400–9200 cm2/V-sec are measured for Si-implanted buffer epi substrates.  相似文献   
40.
High costs and extremely long and expensive R & D programmes have led to extensive involvement by governments in decisions concerning nuclear reactors. The authors examine the decision-making processes of the British nuclear industry, looking in particular at the history of the Advanced Gas-cooled Reactor (AGR). They conclude that both the institutional framework in which the decision was made and the decision itself give cause for concern. In particular the lack of public discussion and the dual role of the UKAEA as both prototype developer and technical adviser to the government make objective judgement difficult.  相似文献   
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