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981.
An automatic piped aerosol system (Accudose TM) using 0.7% synergized pyrethrin insecticide, was tested at a typical narrow cage poultry farm for the control of adult house flies, Musca domestica L. A similar narrow cage poultry farm was used as a control with all house fly control measures left up to the cooperating poultryman. AccudoseTM was compared with other house fly control methods at other similar farms which included three types of man-portable ultra volume (ULV) generators and an integrated (biological-chemical) program. Results of the five month test demonstrated that the AccudoseTM system suppressed house fly populations better than other control methods.  相似文献   
982.
This paper reports the results of a study by and of chairmen of pathology departments in American and Canadian medical schools directed toward discovering chairmen's perceptions and attitudes about the future of pathology. Over 100 of a total of 143 chairmen participated in some or all phases of this study in which the Delphi approach was used. Sixty-five chairmen completed all four rounds of questionnaires. Most chairmen are deeply concerned about increasing federal regulation of medicine. They expect to play a greater role in all phases of medical education with more emphasis on the basic science aspects of pathology. They also foresee a desirable shifting of residency training programs away from small hospitals to the larger medical centers. This shift will result in fewer but longer training programs.  相似文献   
983.
Aminopyrine metabolism was assessed by the aminopyrine breath test (ABT) in 153 patients with malignant disease, of whom 75 had hepatic neoplasm and 78 had none. Radioactive carbon dioxide (14CO2) exhalation was measured two hours after oral administration of a trace dose of carbon-14 labeled aminopyrine. The ABT was correct in 62 of 75 (83%) patients with hepatic neoplasm and in 73 of 78 (94%) patients without. It was correct in 16 of 22 (73%) patients who had hepatic neoplasm without abnormal serum biochemistry. Aminopyrine metabolic clearance rate (AMCR) was 32.4 ml/min in patients with hepatic neoplasm and 103.4 +/- 18.8 ml/min in the patients without. There was a highly significant correlation between ABT and AMCR (r =.76, P less than .01). We conclude that aminopyrine metabolism is depressed in most patients with hepatic neoplasm and that the ABT affords a useful method for detecting malignant tumors of the liver.  相似文献   
984.
Creep and creep recovery of human fibrin clots in small shearing deformations have been investigated over a time scale from 24 to 10(4) s. Coarse, unligated clots and fine clots ligated by fibrinoligase in the presence of calcium ions were studied to suppliement previous data on coarse ligated and fine unligated clots. Stress was found to be proportional to strain up to at least a maximum shear strain (in torsion geometry) of 6.2%. The initial modulus (25 s after imposition of stress) is proportional to approximately the 1.5 power of concentration for fine ligated and coarse unligated clots. For fine unligated closts there is comparatively little creep subsequent to the initial deformation; ligation (in this case involving mostly the gamma chains) reduces the creep to nearly zero. For coarse unligated clots, there is substantially more creep under constant stress, and creep recovery is not complete. Ligation (in this case involving both camma and alpha chains) alrgely supresses the creep and causes the recovery to be complete. If the structure if fully formed before creep begins, tests of creep recovery by the Boltzmann superposition principle show adherence to linear visoelastic behavior for all four clot types. Otherwise, the Boltzmann test fails and the recovery is much less than calculated. For fine ligated clots, the observed recovery agrees well with that calculated on the basis of a dual structure model in which an additional independent structure is built up in the deformed state, so that the state of ease after removal of stress is a balance between two structures deformed in opposite senses. It is postulated that the coherence and elastic modulus of the fine ligated clot are largely due to steric blocking of long protofibrils with a high flexural stiffness. In the coarse clot, it is proposed that the structure involves extensive branching of thick bundles of protofibrils, which become permanently secured by the ligation of the alpha chains of the fibrin.  相似文献   
985.
A series of 4-amino-2,2-diarylbutyronitriles (3) prepared for testing as inhibitors of gastrointestinal propulsive activity did not show any enhancement over such existing agents as diphenoxylate and loperamide. However, conversion of the nitrile group to a 2-methyl-1,3,4-oxadiazol-5-yl function led to compounds 5g and 5j, statistically equipotent to diphenoxylate and loperamide in the mouse and showing a very low order of analgesic activity. Structural modifications determined that the best separation of antipropulsive and analgesic effects was obtained when the amino group was bicyclic and the oxadiazole ring had a 2-methyl substituent. The most potent compounds were and analogues of diphenoxylate and loperamide where the oxadiazole ring was present, but these compounds had marked analgesic activity.  相似文献   
986.
Societal attitudes toward the medical profession are apparently undergoing a change from awe and total respect to a more critical assessing of accountability and credibility. Based on mass media reports and the increasing number of malpractice suits, it would appear that a rational, unbiased review of medical doctors, hospital personnel, and care received is in order. This review should be concerned with technical aspects of medicine as determined by highly competent professionals and the consumer's view of the medical care he receives. The latter review should logically be taken directly to the consumers of medical care to determine their satisfaction with the care they received. Because of the varied areas of specialty within the medical profession, there are different types of relationships between doctors and their patients. The obstetrician, for instance, is usually associated with pregnancy as a joyful event, in contrast to a surgeon whose diagnosis may seldom be accompanied by joy. Satisfaction with medical care could thus be expected to vary according to the area of specialty and may be related to factors over which doctors have no control, factors which initially bring the patient to the doctor for care. The degree of anxiety related to the patient's condition could also be expected to contribute to the degree of satisfaction expressed by the patient.  相似文献   
987.
The eicosanoid generating potential of tunic, branchial basket, intestine, ovary and tadpole larvae from the sea squirt, Ciona intestinalis, was examined using a combination of reverse phase high performance liquid chromatography, gas chromatography-mass spectrometry and enzyme immunoassay. All organs examined synthesized the lipoxygenase products 12-hydroxyeicosapentaenoic acid (12-HEPE) and 8-HEPE implying that both 8- and 12-lipoxygenase activity are widely distributed in this species. In addition, tunic and branchial basket generated significant amounts of 8,15-diHEPE and smaller amounts of 8,15-dihydroxyeicosatetraenoic acid (8,15-diHETE), while tunic alone generated small amounts of conjugated tetraene-containing material with a UV chromophore and mass ion characteristic of a lipoxin-like compound. The broad range lipoxygenase inhibitors, esculetin and nordihydroguaiaretic acid, both caused a significant dose dependent inhibition of 12-HEPE and 8,15-diHEPE biosynthesis in tunic, while the specific 5-lipoxygenase inhibitor, REV-5901, and the specific 5-lipoxygenase activating protein inhibitor, MK-866, had no observable effect on the lipoxygenase profile of this tissue. Tunic, branchial basket, intestine and ovary all generated significant amounts of prostaglandin (PG) E and PGF immunoreactive material and smaller amounts of thromboxane B immunoreactive material as measured by enzyme immunoassay. The non-specific cyclooxygenase (COX) inhibitor, indomethacin, the selective COX-1 inhibitors, resveratrol and valerylsalicylate, and the specific COX-2 inhibitors, NS-398, etolodac and DFU (5,5-dimethyl-3-(3-fluorophenyl)-4-(4-methylsulphonyl) phenyl-2(5H)-furanone) all caused a significant dose dependent inhibition of the biosynthesis of PGE immunoreactive material. However, the specific COX-2 inhibitors were most effective, perhaps implying that a COX-2-like enzyme may be present in this species.  相似文献   
988.
Following a series of lesions in dorsal (DPML) and ventral (VPML) divisions of tree shrew (Tupaia) paramedian lobule (PML), the distribution of degenerated axons within the deep cerebellar nuclei was determined using the Fink and Heimer ('67) method. Damage to PML produced axonal degeneration in lateral (NL), anterior interposed (NIA), and posterior interposed (NIP) cerebellar nuclei. No degenerated fibers could be traced to either the medial cerebellar nucleus or vestibular complex, via juxtarestiform body, from lesions in PML. Corticonuclear fibers to NL, NIA, and NIP from PML cortex are topographically organized. Subsequent to lesions of lateral DPML, axonal debris is found in rostral and medial NL, while the lateral edge of VPML projects primarily into medial NL. According to the terminology of Voogd ('69) these lateral regions of PML represent the D zone. The NIP receives corticonuclear input from a relatively wide middle area of both portions of PML, interpreted as the C2 zone. There is some evidence which suggests that medial portions of the C2 area of DPML project into more lateral areas of NIP, while lateral regions of this zone in DPML are related to more medial NIP. This projection pattern is invited for the C2 area of VPML; medial C2 to medial NIP, lateral C2 to lateral NIP. Corticonuclear fibers of PML which enter NIA appear to arise from a narrow, irregular, partially discontinuous strip of cortex located at the interface of the D and C2 areas in lateral PML and from a wider, more regular region in the most medial areas of this lobule. These represent, respectively, the C3 and C1 zones. Although an overall pattern of zones is present, there is evidence to suggest that their spatial organization differs from DPML to VPML. The zonal patterns appears to be more obvious in VPML, while this pattern for DPML is less distinct. This is interpreted as indicating that either (1) zones C1--C3 overlap to a greater degree in DPML than in VPML, or (2) zones C1 and C3 may converge in rostral DPML, partially obliterating the intervening zone C2. The different ways in which zonal terminology is applied to both corticonuclear and certain of the afferent cerebellar systems are discussed.  相似文献   
989.
990.
PURPOSE: To define arthroscopic criteria for synovitis (SYN) reflecting specific histologic changes. Arthroscopic observations in the temporomandibular joint of patients with internal derangement were compared with histologic patterns in synovial biopsies obtained during arthroscopy. PATIENTS AND METHODS: Arthroscopic biopsies were obtained in 31 joints of 31 patients using an oriented semiblind technique. The histologic changes in the biopsies were compared with those in age-matched reference material obtained at autopsy. RESULTS: Microscopic examination of the reference material showed inflammation in three specimens (18%), whereas it showed inflammation in 22 patient specimens (71%). Biopsies from the patients also exhibited more pronounced inflammation. According to conventional criteria, arthroscopy showed mild SYN (increased vascularity) in 51%, moderate changes in 39%, and more pronounced changes in 10% of the joints. The presence of moderate or pronounced arthroscopic signs of SYN (capillary hyperemia and synovial hyperplasia), correlated well with the histologic diagnosis of SYN. This was in contrast to patients with mild arthroscopic SYN (increased vascularity). CONCLUSION: Increased vascularity seen during arthroscopy must be questioned as a sign of SYN. More reliable criteria seem to be capillary hyperemia and synovial hyperplasia.  相似文献   
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