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101.
The flight response of maleTrichoplusia ni was observed in a flight tunnel to a sex pheromone blend composed of six components:Z7–12Ac, 12Ac,Z5-12Ac, 11-12Ac,Z7-14Ac, and Z9-14Ac. The number of males reaching a 3000-g source of this blend was > 95%, equal to that observed to female glands and significantly greater than with the previously identified two-component blend (Z7-12Ac + 12Ac). In subtraction tests, all five-component blends, with the exception of the blend lacking the primary componentZ7-12Ac, and several four-component blends elicited similar peak levels of upwind flight, source contacts, and hairpencil displays to that observed with the six-component blend. We characterize the substitution of certain minor components for one another as a form of redundancy in the chemical signal and suggest that it contributes to response specificity and signal recognition in males. The results also support the concept that the full blend of components acts as a unit to influence male behavior at all phases of the response. Individual minor components were not responsible for eliciting specific behaviors in the sequence.  相似文献   
102.
Malaria is one of the main health problems in the non-immune immigrant workers and army personnel of the malaria endemic areas in Myanmar. Due to changes in the vector bionomics and multiresistant strains of P. falciparum, chemoprophylaxis alone is not an effective means of control of malaria in them. So it is envisaged that the combined used of personal protective measures (deltamethrin impregnated bed-nets, scalves and hand-bands) and the chemoprophylaxis will be an effective means of control of malaria in the define group of people. The study also intended to find out the side effects of the deltamethrin and feasibility and acceptability of methods by the users. The study was conducted in Theini Township, Northern Shan State, from March to November 1993. The study population consisted of all ages of both sexes 554 and 440 persons in the test and control groups respectively. At the initial phase of the study, malaria infected persons from both the groups were treated. The experimental group received personal protective measures with impregnation of bed-nets using 25 mg ai/m2 of deltamethrin at 4 monthly intervals and the scarves and hand-bands at twice the concentration of the insecticides at monthly intervals. Chemoprophylaxis was given to both the groups at weekly intervals using age adjusted dosage of Pyrixine tablet (sulfadoxine-pyrimethamine). The parasitological, entomological, and epidemiological indices were collected at two month intervals in both the groups. The study clearly showed the impact of personal protective measures and chemoprophylaxis on malaria infection in the studied subjects. During the study period, the out patient malaria cases of the test group was 6% to 11.2% and that of the control group was 12% to 21.6% in Theini Hospital. The reinfection rate of the test group (0.9 to 4.7%) was also significantly lower than the control group (6.1 to 14.3%) from July to November. Acceptance of the treated bed-nets, scarves and hand-bands was high and good compliance was found in the follow up. The results of the study clearly showed that malaria can be controlled effectively in the defined group of persons for a malaria transmission season by using chemoprophylaxis and personal protective measures.  相似文献   
103.
The identification of improved medical countermeasures against exposure to chemical warfare nerve agents (CWNAs), a class of organophosphorus compounds, is dependent on the choice of animal model used in preclinical studies. CWNAs bind to acetylcholinesterase and prevent the catalysis of acetylcholine, causing a plethora of peripheral and central physiologic manifestations, including seizure. Rodents are widely used to elucidate the effects of CWNA-induced seizure, albeit with a caveat: they express carboxylesterase activity in plasma. Carboxylesterase, an enzyme involved in the detoxification of some organophosphorus compounds, plays a scavenging role and decreases CWNA availability, thus exerting a protective effect. Furthermore, species-specific amino acid differences in acetylcholinesterase confound studies that use oximes or other compounds to restore its function after inhibition by CWNA. The creation of a human acetylcholinesterase knock-in/serum carboxylesterase knockout (C57BL/6-Ces1ctm1.1LocAChEtm1.1Loc/J; a.k.a KIKO) mouse may facilitate better modeling of CWNA toxicity in a small rodent species. The current studies characterize the effects of exposure to soman, a highly toxic CWNA, and evaluate the efficacy of anti-seizure drugs in this newly developed KIKO mouse model. Data demonstrate that a combination of midazolam and ketamine reduces seizure duration and severity, eliminates the development of spontaneous recurrent seizures, and protects certain brain regions from neuronal damage in a genetically modified model with human relevance to organophosphorus compound toxicity. This new animal model and the results of this study and future studies using it will enhance medical countermeasures development for both defense and homeland security purposes.  相似文献   
104.
This study presents advances in the application of laser‐based methods to image and measure the luminescence lifetime of historical wall paintings containing Egyptian blue. Samples from Tel Kabri, a major Canaanite palace dated to 18th C. BCE, from the Roman city of Caesarea Maritima, from the 4–5th C. Byzantine tomb in Lohamei HaGeta'ot, and from a 6th C. Byzantine church of Shivta have been studied using time‐resolved photoluminescence spectroscopy and imaging. Taking into account the high sensitivity of the emission lifetime to the microenvironment surrounding the emitting species, here, we show for the first time that the optical emission from historical samples containing Egyptian blue particles exhibits meaningful lifetime variations. Indeed, the wall paintings from Tel Kabri, Lohamei HaGeta'ot, and Shivta present the shortest emission lifetime, close to 115–120 μs. However, samples from Caesarea Maritima wall paintings exhibit a different optical emission, which dumps more slowly with an average lifetime of 130 μs. Egyptian blue pigment particles, synthetised with modern methods, are associated with the longest emission lifetime of 147 μs. This study suggests that there is a possible link between the lifetime of the pigment's emission and its synthesis method.  相似文献   
105.
To examine whether the concomitant administration of a gonadotrophin-releasing hormone agonist (GnRHa) during combination chemotherapy to young women with lymphoma may facilitate preservation of gonadal function, a prospective clinical protocol was undertaken in 18 cycling women with lymphoma, aged 15-40 years. Thirteen patients suffered from Hodgkin disease (HD) and 5 from non-Hodgkin lymphoma. After informed consent a monthly injection of depot D-TRP6-GnRHa was administered for a maximum of 6 months starting prior to chemotherapy. Most of these patients (15/18) were treated with the MOPP/ABV(D) combination chemotherapy followed by mantle field irradiation in 10 patients. Hormonal profile [luteinizing hormone (LH), follicle stimulating hormone (FSH), oestradiol, testosterone, progesterone, insulin-like growth factor (IGF)-1, prolactin] was taken before the GnRHa/chemotherapy co-treatment, and monthly thereafter until resuming spontaneous ovulation and menses. This group of prospectively treated lymphoma patients was compared to a matched control group of 18 women (aged 17-40 years) who have been treated with chemotherapy, mostly MOPP/ABV (14/18), with (11) or without (7) mantle field radiotherapy. Fourteen had Hodgkin's and four non-Hodgkin's lymphoma. Gonadal function was determined clinically, hormonally (LH, FSH, oestradiol, progesterone), and sonographically. Two of the patients in each group died from refractory disease. Of the remaining 16 patients, 15 (93.7%) resumed spontaneous ovulation and menses within 3-8 months of termination of the combined chemotherapy/GnRHa co-treatment. In contrast, only seven (39%) of the 18 similarly treated patients in the control group (chemotherapy without GnRHa) resumed ovarian cyclic activity (regular menses). The other 11 experienced premature ovarian failure (POF) (61%). Out preliminary data suggest a possible significant protective effect of GnRHa co-treatment with chemotherapy from irreversible ovarian damage (POF).  相似文献   
106.
Conformance evaluation methodology and protocol testing   总被引:1,自引:0,他引:1  
  相似文献   
107.
介绍 过去几年,发光二极管(LED,Light Emitting Diode)的应用领域进行了巨幅的扩展,其中成长最快也最具潜力的市场是液晶显示屏(LCD)的背光应用,几年间白色发光二极管已经随着小型显示屏的背光应用逐渐普遍,目前几乎所有移动电话中的彩色液晶面板都由发光二极管提供背光,最近白色发光二极管更开始迈入需要更高性能和更长工作时间的膝上型显示屏背光应用,然而发光二极管在进入大尺寸显示屏,如个人电脑显示屏与电视应用的路途上并未顺利,因为除了更佳性能和更长工作时间外,大型液晶面板需要使用如红、绿、蓝(RGB)这类发光二极管来创造更丰富的色彩范围,才能提供比使用CCFL背光更好的采购诱因.  相似文献   
108.
Complex interdependence in task-performing groups.   总被引:2,自引:0,他引:2  
Proposed a model of work group performance based on the consequences of complex interdependence (CI), which is defined as the interactive effects of task, goal, and feedback combinations. The study consisted of a 4 (task interdependence: pooled, sequential, reciprocal, or team)?×?2 (goal interdependence: individual or group)?×?2 (feedback interdependence: individual or group) completely crossed factorial design using 118 3-person groups working in a laboratory setting on a performance appraisal task. The results of group-level analyses demonstrated the impact of CI on the perceived effectiveness of group task strategy. In turn, task strategy and intragroup conflict partially mediated the effects of CI on group performance quantity and quality. Design applications for group work are presented and discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
Three lactating Holstein cows with rumen cannulae were used in a 3 X 3 Latin square arrangement of treatments to study effects of methionine source on ciliated protozoa numbers and volatile fatty acid concentrations in the rumen. Cows were fed total mixed diets twice daily of 60% grain mix, 21% corn silage, and 19% alfalfa hay (dry basis). Methionine hydroxy analog, DL-methione, and sodium sulfate were added on an equal sulfur basis. Experimental periods were 14 d with four rumen samples taken daily on d 13 and 14. Total ciliated protozoa were higher when cows were fed DL-methionine than when fed methionine hydroxy analog or sodium sulfate. Ruminal concentrations of butyric acid and isobutyric acid were higher for the DL-methionine treatment than for analog or sodium sulfate treatments. Isovaleric acid concentrations were also higher in fluid from cows fed methionine compared with cows fed the analog.  相似文献   
110.
The diagnostic value of 99mtechnetium-dimercaptosuccinic acid (DMSA) scintigraphy, ultrasonography and renal functional parameters [urine N-acetyl-beta-D-glucosaminidase (NAG)/creatinine and urine albumin/creatinine quotients] in acute pyelonephritis (APN) were studied in 39 children (28 girls, 11 boys, median age 9 months, range 2 weeks to 9.4 years, 28 patients < 1 year, 11 patients > 1 year) with first-time urinary tract infection. Ultrasonography of the urinary tract was performed on admission and together with DMSA scintigraphy (< 10 days from admission). Urine NAG/creatinine and urine albumin/creatinine quotients were measured daily and after 6-8 weeks. Ultrasonography revealed abnormalities in 12 of 39 (31%) patients [11/32 patients (34%) with positive DMSA scintigraphy], while DMSA uptake defects were present in 32 of 39 (82%) patients [21/28 < 1 year (75%), 11/11 > 1 year (100%), P = 0.08]. Urine NAG/creatinine and urine albumin/creatinine quotients were significantly higher in children < 1 year with APN, as well as in non-renal fever controls, than in older children. However, in both age groups the urine NAG/creatinine and urine albumin/creatinine quotients were significantly higher in APN than in non-renal fever. The urine NAG and albumin excretion decreased rapidly after the initiation of antimicrobial therapy and had normalized at 6-8 weeks. The size and grade of the DMSA uptake defect (DMSA score) did not correlate with duration of disease at admission, maximum C-reactive protein or maximum fever. The urine NAG/creatinine quotient in the children < 1 year showed, however, a significant correlation with the DMSA score (r = 0.58, P < 0.05), while no correlation was found in the older children. We conclude that DMSA scintigraphy is a sensitive method to confirm the clinical diagnosis of APN, although a substantial number of infants appear to have normal scans. Early determination of the urine NAG/creatinine and albumin/ creatinine quotients may further improve the diagnostics in the infant.  相似文献   
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