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91.
The study involved 355 specimens of STD clinic patients collected from Beijing, Shantou and Wuhan, for the detection of Neisseria gonorrhoeae, Chlamydia trachomatis, Ureaplasma urealyticum by polymerase chain reaction. The results showed that the positive rate of Neisseria gonorrhoeae being the highest in the patients attending STD clinics from the three cities. The detection rate of Neisseria gonorrhoeae in male patients was higher than in females. The positive rates of Chlamydia trachomatis and Ureaplasma urealyticum in the three cities differed from each other greatly. Polymerase chain reaction was suitable for clinical Jetection and epidemiological study of the three kinds of STD pathogens.  相似文献   
92.
We investigated various factors related to secondary hyperparathyroidism among hemodialysis patients. Subjects were 26 patients (20 men and 6 women) ranging in age from 24 to 75, treated at an ordinary hemodialysis center throughout the year 1991. The serum inorganic phosphate level and serum intact PTH level varied greatly from 2.5 to 12.5 mg/dl and from 10 to 1,102 pg/ml (normal range, 10-60 pg/ml), respectively. All patients were classified according to the serum intact PTH level into two groups: those with less than 120 pg/ml (Group I) and those with 120 pg/ml or more (Group II). The patients in Group I responded well to hemodialysis and drug therapy, but those in Group II were likely to have secondary hyperparathyroidism. In all patients in Group II, the PTH level increased markedly in the summer. This may be attributed to insufficient ingestion of calcium, vitamins, and other nutrients due to loss of appetite.  相似文献   
93.
The results showed that microscopic structure in biennial roots, the contents of B and Mn in nutritive organ and beta-sitosterol content in roots, stems of Morinda officinalis were affected markedly. The total sugar content in the roots and aerial stems was decreased by 5.42%-15.29%.  相似文献   
94.
The effects of different natural stimulants on the afferent unit discharge of rabbit carotid chemoreceptors were studied in the in vitro carotid body- sinus nerve preparation. A total of 32 chemoreceptive units were recorded. The results were as follows: (1) Of the 32 units, 10 (31%) showed chemosensory responses only to PO2 decrease; 9 (28%) to all stimulants (PO2 decrease, PCO2 increase and pH decrease); 9 (28%) to PO2 decrease and PCO2 increase; 3 (9%) to PO2 decrease and pH decrease; only one to pH decrease. (2) The potency of the three natural stimulants in eliciting the changes in intensity of discharge showed a decreasing order as follows: PO2 decrease > PCO2 increase > pH decrease. The above results suggest that the carotid body may contain only one or a combination of 2 or 3 kinds of chemoreceptors respectively sensitive to decrease PO2 to increase PCO2 or decrease pH.  相似文献   
95.
The present study was designed to find the reliable parameter(s) for the detection of early neurotoxicity following intracarotid (IC) administration of cisplatin. IC administration was performed for 60 minutes in female Wistar rats derived into four groups according to the dose given (1 mg, 1.2 mg, and 1.5 mg of cisplatin, and normal saline in control rats). Blood-brain barrier (BBB) permeability and local cerebral blood flow (LCBF) were measured by a double-tracer autoradiography technique using 1-[14C]-alpha-aminoisobutyric acid (14C-AIB) and 4-[18F] fluoroantipyrine (18F-FAP), respectively. Blood chemistry and neuropathology were also examined. BBB permeability was increased only on the ipsilateral side. This increase was dose-dependent, preceded the brain necrosis, and was statistically significant in the hypothalamus (1.2 mg group), auditory cortex and caudoputamen (1.5 mg group). Renal dysfunction was often observed. The changes in the LCBF did not occur until brain necrosis was noticeable. These findings demonstrate that the increase in the BBB permeability provides a sensitive and reliable indication of an early toxicity to brain tissue following IC administration of cisplatin.  相似文献   
96.
97.
The MOCVD technique was used to form thin films of chromia and/or of a rare-earth-element oxide on the surface of F17Ti stainless-steel samples. These oxides were deposited alone or together, successively or by codeposition. Coated samples were then subjected to high-temperature oxidation tests, either under isothermal conditions at 1273 K for 50 h, or under cyclic conditions at 1223 K for 40 cycles. An improved oxidation behavior was observed in every case, especially with codeposited Ln2O3-Cr2O3. Weight gain decreased during oxidation, compared with an uncoated sample, and scale spallation, generally observed under cyclic conditions, disappeared. Longer time experiments were also carried out. Large differences were observed, depending on the sample surface treatment.  相似文献   
98.
After an introduction to the syntax of Gödel systemT, we present its naive denotational semantics in the domain of lazy natural numbers and show an adequacy property relating syntax and semantics. We recall the natural restrictions of systemT delineating primitive recursion as a subsystem. We discuss the weakness of primitive recursion by exhibiting a simple unary algorithm whose denotation is not the semantics of a primitive recursive algorithm. This algorithm can nevertheless be programmed in systemT by using the power of higher-order (functional) definitions. Generalizing this example, we obtain a representation theorem, asserting that every reasonable algorithm of typeN N can be programmed in systemT. We conclude by discussing what is known in the case of higher arities.  相似文献   
99.
A mass hepatitis B vaccination program began in Taiwan in 1984. In order to determine the immune status of hepatitis B virus (HBV) infection among preschool children, a total of 25 kindergartens in 20 townships and metropolitan precincts in central Taiwan were randomly selected through stratified sampling. Serum specimens of 2130 healthy preschool children aged 2-6 years old were screened for the HBV markers and liver function in 1996. HBV surface antigen (HBsAg), antibody against HBsAg (anti-HBs) and antibody against HBV core antigen (anti-HBc) were tested by reverse passive hemagglutination (RPHA), enzyme immunoassay (EIA) and radioimmunoassay (RIA) using commercial kits. HBV vaccination rate of the preschool children was 98%, and complete vaccination rate (three or four doses of HBV vaccine) was 94%. The HBsAg seropositive rate was 4.5% among incomplete vaccinees and 1.3% among complete vaccinees. The anti-HBs was detectable in 1637 of 2000 complete vaccinees (81.9%) and in 53 of 88 incomplete vaccinees (60.2%). The overall prevalence rate of anti-HBc was 2.4% (52 of 2130). The older the age, the lower the anti-HBs seropositive rate. The anti-HBs seropositive rats for complete vaccinees were 100% at 2 years old and 75% at 6 years old. There were no significant differences in HBsAg-seropositive rates and anti-HBs-seropositive rates among different residential areas or ethnic groups. There were three children who were seropositive on HBsAg, anti-HBs and anti-HBc, whether they were infected by the vaccine-induced escape mutant of HBV deserves scrutiny.  相似文献   
100.
BACKGROUND: Panel-reactive antibody (PRA) is commonly used before thoracic organ transplantation to estimate a potential recipient's degree of humoral sensitization. METHODS: To assess the influence of an elevated PRA on survival and the incidence of rejection in pulmonary transplantation, the records of 247 patients that underwent single or double lung transplantation were reviewed. RESULTS: Twenty-one of 247 patients (8.5%) had PRA values greater than 10%. Survival of this population was not significantly different from that of patients with low PRA levels: 74% (low PRA) vs 65% (elevated PRA) at 1 year and 58% in both groups at 3 years. The acute rejection rates (episodes/first 100 days) for the elevated and low PRA groups were 2.1 and 1.9, respectively (p = NS). Obliterative bronchiolitis developed in 38.9% of the high and 31.2% of the low PRA groups (p = NS). Six of 247 patients had a retrospective positive lymphocytotoxic cross-match result; three had PRA values greater than 10%. Patients with a positive cross-match result experienced similar survival and incidence of rejection as the remainder of the population. Among 957 patients evaluated for lung transplantation, 16 (1.7%) had a PRA (with dithiothreitol) greater than 15%. All had a history of pregnancy, blood transfusion, connective tissue disease, or previous transplantation. CONCLUSIONS: Humoral sensitization is uncommon in the lung transplantation population. A modestly elevated PRA does not predict survival or the development of acute rejection or bronchiolitis obliterans. PRA testing before lung transplantation should be reserved for those patients with specific risk factors for humoral sensitization.  相似文献   
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