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61.
A self-report questionnaire module consisting of 24 items, comprising 5 scales and 7 single items, has been developed for measuring health-related quality of life in patients with brain cancer. Module development proceeded through several stages, including a listing of patient, family and health care professional concerns, the writing of items, field testing in 105 patients with brain cancer and subsequent item reduction and scale construction after multitrait scaling analysis and assessment of internal consistency (Cronbach's coefficient alpha). The final version of the module exhibits reasonable test-retest stability over a period of one week. Differences in the responses between patients with recently-diagnosed and recurrent cancer and between patients with a Karnofsky Performance Score (KPS) of 50-70 and 80-100 were in the expected direction, indicating that the module of questions is responsive to differing conditions. Patients with either mental confusion, motor deficit or dysphasia indicated problems in several domains and single items as compared to patients without these neurological deficits. Thus, differences in the responses to the items in the brain cancer module appear to reflect differences in neurological status. In addition, deteriorating neurological status was accompanied by a marked increase in emotional distress, future uncertainty and motor dysfunction. A comparison of the responses in the module with the KPS and with a modified Barthel Activities of Daily Living Index (BADLI) shows moderate correlations, primarily with scales and items that pertain to motor dysfunction, while other scales (such as emotional distress, visual disorder and communication deficit) and most single items are not associated with the KPS or BADLI. Since the emotional distress scale of the module was found to be highly correlated with the emotional function scale of the EORTC QLQ-C30, it could be omitted when the module is used in combination with the QLQ-C30. This would reduce the module to a total of 20 items with four scales and seven single items. The intention is to combine this module of questions with other core or general quality-of-life questionnaires when studying patients with brain cancer in clinical trials.  相似文献   
62.
Insomnia may be periodic and transient, as caused by situational stress, or persistent, as caused by a chronic sleep disorder. Physicians can gain much information concerning the type, probable cause, onset, and duration of insomnia through history taking. A sleep diary may reveal helpful information, and input from the patient's sleeping partner can also be valuable. Complicating disorders, such as heart failure, prostatism, or depression, should be sought and specific treatment prescribed. Chemical dependency, too, requires appropriate treatment. These measures, institution of good sleep-hygiene practices, and behavior modification may resolve sleeplessness. The primary indication for use of hypnotic agents is transient sleep disruption caused by acute stress. When an agent is chosen, onset of action, metabolism, and side effects should be considered, especially in elderly patients. Addictive agents should not be given to patients with substance abuse problems. If insomnia persists, evaluation at a sleep-disorder center is recommended to facilitate design of an appropriate therapeutic regimen.  相似文献   
63.
It has been suggested that volatile anesthetic, isoflurane mediates cardioprotective effects via activation of the ATP-sensitive K+ (KATP) channels. However, no direct evidence has been provided to define whether isoflurane activates cardiac KATP channels using patch-clamp technique. We examined the effects of isoflurane on the KATP channels in rabbit ventricular myocytes by use of patch-clamp technique. Contrary to the results of the in vivo experiments, isoflurane inhibited the channel activity without a change in the single-channel conductance. Isoflurane decreased the channel activity by a decrease in burst duration and an increase in the inter-burst duration. On the other hand, isoflurane diminished the ATP sensitivity of KATP channels, indicating an increased probability of KATP channel opening for a given concentration of ATP after isoflurane anesthesia. The result supports, at least in part, the hypothesis that isoflurane mediates cardioprotective effects via KATP channel activation.  相似文献   
64.
OBJECTIVES: Herein we describe an additional case of myelolipoma of the adrenal gland, an uncommon tumor of the adrenal cortex, that had been incidentally discovered during abdominal US evaluation of the biliary tree. The clinical features, diagnosis and treatment of the condition are discussed. METHODS: Surgical treatment of the biliary tree and myelolipoma was performed through a Chevron transversal incision during the same surgical session. RESULTS: Surgery achieved good results and the postoperative course was unremarkable. CONCLUSIONS: Myelolipoma is a benign nonfunctioning tumor of the adrenal cortex comprised of adipose and hematopoietic tissue. It is usually asymptomatic and incidentally discovered during diagnostic evaluation for other pathologies. The diagnosis is made by US, CT and MRI. There is no agreement on whether surgical treatment is warranted.  相似文献   
65.
Neurotoxic effects are of such breadth and complexity that functional biomarkers (behavioral tests) that integrate many areas of the nervous system predominate in human neurotoxicology research. The increasing distribution of chemical and other manufacturing throughout the world, particularly in developing nations, suggests the acute need to develop biomarkers for chemical exposures and effects that can be employed internationally. A language-free method for training performance on behavioral tests is described, which holds promise for international research that circumvents the vagaries of translation. Four behavioral tests were administered to 74-114 adult US subjects. Procedures, collectively termed shaping, produced effective performance on three tests [Symbol Digit, Vigilant Attention Test (VAT), Digit Span Forward and Backward], and produced appropriate but unacceptably slow performance in initial testing on the Simple Reaction Time test. Effective performance on the Symbol-Digit test also was produced by shaping instruction, without assistance from examiners, in small groups of residents of Taipei (Taiwan) and US children between the ages of 5 and 16.  相似文献   
66.
Familial or X-linked hypophosphatemic rickets (XLHR) is the most common type of rickets in developed countries today. While the dental manifestations of rickets are well reported, there is little information regarding its relationship to dental development and other dental anomalies. This investigation studied the rate of dental development and associated dental anomalies in 19 XLHR subjects compared with 38 race-, age-, and sex-matched control children. The results showed that in both XLHR and control children, no significant differences existed in dental age compared with the respective chronological age, indicating that rickets did not affect the rate of dental development. Longitudinal growth curves of seven XLHR and matched control children substantiated that relationships of dental to chronological ages were comparable in both groups. Male XLHR subjects showed significantly increased tendency for dental taurodontism with mean Crown-Body (CB):Root (R) ratio of 1.1 compared with 1.0 in females and 0.8 in controls (P < 0.02). Male XLHR children also showed significantly increased prevalence (50%) of ectopic permanent canines compared with control children (8%, P < 0.01).  相似文献   
67.
We examined the cytotoxic effects of radiation delivered in daily fractions at clinically relevant doses in plateau phase cultures of skin fibroblast cell strains derived from ataxia telangiectasia (AT) heterozygotes, patients with unusually sensitive responses to radiotherapy, apparently normal patients, and cell bank controls. A gradual linear reduction in surviving fraction versus total dose was observed in the control group, comprised of apparently normal individuals and one patient with a normal clinical response to radiotherapy, after exposure to daily fractions of 2.0 Gy. There was a much steeper decline in surviving fraction among the AT heterozygotes and the group with sensitive responses to radiotherapy, such that after six daily fractions of 2.0 Gy (12 Gy total dose), the mean surviving fraction of the control group was significantly different from that of the AT heterozygotes (P = 0.0009) and that of the patients with unusually sensitive responses to radiotherapy (P = 0.0002). We propose that this assay may be a useful means of identifying cell strains from AT heterozygotes. Based on these results, the hypothesis is discussed that patients who suffer unusually sensitive clinical reactions to radiotherapy may be AT heterozygotes.  相似文献   
68.
A comparative evaluation of the macrodilution method and the Alamar colorimetric method for the susceptibility testing of amphotericin B, fluconazole, and flucytosine was conducted with 134 pathogenic yeasts. The clinical isolates included 28 Candida albicans, 17 Candida tropicalis, 15 Candida parapsilosis, 12 Candida krusei, 10 Candida lusitaniae, 9 Candida guilliermondii, 18 Torulopsis glabrata, and 25 Cryptococcus neoformans isolates. The macrodilution method was performed and interpreted according to the recommendations of the National Committee for Clinical Laboratory Standards (document M27-P), and the Alamar colorimetric method was performed according to the manufacturer's instructions. For the Alamar colorimetric method, MICs were determined at 24 and 48 h of incubation for Candida species and T. glabrata and at 48 and 72 h of incubation for C. neoformans. The overall agreement within +/- 1 dilution for Candida species and T. glabrata against the three antifungal agents was generally good, with the values for amphotericin B, fluconazole, and flucytosine being 85.3, 77.9, and 86.2%, respectively, at the 24-h readings and 69.3, 65.2, and 97.2%, respectively, at the 48-h readings. Most disagreement was noted with fluconazole against C. tropicalis and T. glabrata. Our studies indicate that determination of MICs at 24 h by the Alamar colorimetric method is a valid alternate method for testing amphotericin B, fluconazole, and flucytosine against Candida species but not for testing fluconazole against C. tropicalis and T. glabrata. For flucytosine, much better agreement can be demonstrated against Candida species and T. glabrata at the 48-h readings by the Alamar method. Excellent agreement within +/- dilution can also be observed for amphotericin B, fluconazole, and flucytosine (80, 96, and 96%, respectively) against c. neoformans when the MICs were determined at 72 h by the Alamar method.  相似文献   
69.
RK Maloney  WK Chan  R Steinert  P Hersh  M O'Connell 《Canadian Metallurgical Quarterly》1995,102(7):1042-52; discussion 1052-3
PURPOSE: The Summit Therapeutic Refractive Clinical Trial is a nine-center prospective, nonrandomized, self-controlled trial to assess the efficacy, stability, and safety of using a standardized technique of excimer laser photorefractive keratectomy (PRK) to correct residual myopia in eyes with previous refractive surgery or cataract surgery. PATIENTS AND METHODS: Eligible eyes with a mean residual myopia of -3.7 +/- 1.8 diopters (D) (range, -0.63 to -11.00 D) underwent PRK with a 193-nm excimer laser for myopic corrections between -1.50 and -7.50 D. Standardized settings were used for the ablation zone, ablation rate, repetition rate, and fluence. One hundred seven of the first 114 treated eyes were examined 1 year after PRK, with 98% of eyes having had refractive keratotomy and 2% having had cataract surgery. RESULTS: One year postoperatively, the mean manifest spherical equivalent refraction was -0.6 +/- 1.4 D (range, -6.50 to 2.50 D); 63% of eyes were within +/-1.00 D of the attempted correction; and uncorrected visual acuity was 20/40 or better in 74% of eyes. Twenty-nine percent of eyes lost two or more Snellen lines of best-corrected visual acuity, and central corneal haze was moderate or severe in 8% of eyes. CONCLUSIONS: Excimer laser PRK is effective in reducing residual myopia after previous refractive and cataract surgery. However, it is less accurate than PRK in eyes that did not undergo surgery and is more likely to cause a loss of best-corrected visual acuity 1 year after treatment.  相似文献   
70.
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