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991.
CONTEXT: Contraceptive use has been legal in France for the past 30 years, and patterns of use changed substantially from the 1960s to the 1980s. Given the rapidity with which use patterns change and the possible impact of rising concern about infection with HIV and other sexually transmitted diseases, it is important to determine trends of contraceptive practice into the 1990s. METHODS: A total of 5,900 French households were selected in 1994 for inclusion in the Fertility and Family Survey. Respondents were questioned about their contraceptive use patterns and family formation status. The results were compared with those of comparable surveys conducted in 1978 and 1988. RESULTS: Two-thirds of French women used some form of reversible contraceptive method in 1994. Oral contraceptive use has grown steadily in France: About 40% of women aged 20-44 reported using the pill alone or combined with another method in 1994, compared with 34% in 1988 and 28% in 1978. Condom use has also been on the rise: Nearly 8% of women were using condoms alone or combined with another method in 1994, up from 5% in 1988 and 6% in 1978. IUD use has declined from 19% in 1988 to 16% in 1994, and both male and female sterilizations remain rare. CONCLUSIONS: Contraceptive behavior in France appears unique among developed countries, with fairly high levels of oral contraceptive use--even among older women--relatively high levels of IUD use and little reliance on either male or female sterilization. As with other countries, however, condom use has climbed in recent years, and is especially common at first intercourse.  相似文献   
992.
The weaver (wv) mutant mouse manifests severe locomotor defects, a deficiency in granule cells of the cerebellum, and cellular deficits in the midbrain dopaminergic system. The wv phenotype is associated with a missense mutation in the pore region of the G-protein-gated inwardly rectifying potassium channel, GIRK2. The homozygous male wv mouse is essentially infertile due to an inadequate level of sperm production. Females are fertile although they also manifest the neurological phenotype. Homozygotes of both sexes have reduced body weight. We have evaluated the hypothalamic-pituitary-gonadal axis in heterozygote and homozygote male and female wv mutants in comparison with wild-type controls. Testicular weight was significantly reduced in the homozygous males, due to degenerative changes of seminiferous epithelium. Serum and pituitary content of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and prolactin were normal in all groups, and the normal sex differences were noted (FSH and LH higher in males, prolactin higher in females). Pituitary growth hormone (GH) concentration was normal, with control and mutant males showing higher GH than females. Serum testosterone levels were normal in the mutants, as was testicular testosterone. Testicular alpha-inhibin content was mildly reduced, but high in proportion to testicular weight. The defect in spermatogenesis appeared predominantly in the postmeiotic stages. In situ hybridization was consistent with expression of some GIRK2 mRNA isoforms in seminiferous epithelium. There were no significant differences between genotypes in the levels of dopamine, dihydroxyphenylacetic acid, serotonin and 5-hydroxyindoleacetic acid in the mediobasal and preoptic hypothalamic regions. Homovanillic acid levels in these two areas were, however, reduced in wv homozygotes compared to wild-type animals. In the light of normal pituitary hormone levels, normal hypothalamic monoamine concentrations and normal sex differences in gonadotropins, we conclude that the infertility in the male homozygote wv mouse lies within the tubule and is probably a primary defect in the germ cells. The hormonal data suggest that Leydig cell function, and at least some aspects of Sertoli cell function, are normal in the mutant mice.  相似文献   
993.
The vaccine potential of a mutant herpes simplex virus (HSV) type 1, with a deletion in the glycoprotein H (gH) gene, was evaluated. The virus requires a gH-expressing cell line for multi-cycle growth but can complete a single cycle of infection in noncomplementing cells. Such viruses, termed DISC (disabled infectious single cycle) viruses, should be safe, yet still able to stimulate humoral and cell-mediated responses against a broad range of virus antigens in vaccinated hosts. Prophylactic vaccination of guinea pigs with DISC HSV-1, by ear scarification or direct infection of the vaginal mucosa, afforded a high degree of protection against HSV-2-induced primary genital disease and reduced significantly the frequency of subsequent disease recurrence. There was also a trend toward reduced recurrence following therapeutic vaccination of animals already infected with HSV-2. DISC HSV vaccination, therefore, offers an effective route for control of HSV disease.  相似文献   
994.
995.
Human papillomavirus (HPV) has been implicated in the pathogenesis of anal carcinoma, which is increased in homosexual men. Little is known about the serologic response to HPV in normal or immunosuppressed men; therefore, HIV-infected and -uninfected homosexual men were screened for HPV-6 and -16 capsid antibodies. HIV-infected men had increased HPV DNA detection but did not significantly differ in the prevalence of serum HPV antibodies. HPV-6 DNA detection and the presence of anal warts were significantly correlated with serum antibody overall and in the HIV-infected subgroup. HPV-16 DNA detection was not significantly correlated with serum antibody overall or in either subgroup; however, HIV-infected men with high-grade anal squamous intraepithelial lesions were significantly more likely to have HPV-16 antibodies. HIV-infected men are able to generate an antibody response to HPV, and a lack of serum HPV antibodies cannot explain the increased HPV-associated disease seen in HIV-infected men.  相似文献   
996.
We have shown previously that, in less than 4 ms, the unfolded/oxidized hen lysozyme recovered its native secondary structure, while the reduced protein remained fully unfolded. To investigate the role played by disulfide bridges in the acquisition of the secondary structure at later stages of the renaturation/oxidation, the complete refolding of reduced lysozyme was studied. This was done in a renaturation buffer containing 0.5 M guanidinium chloride, 60 microM oxidized glutathione, and 20 microM reduced dithiothreitol, in which the aggregation of lysozyme was minimized and where a renaturation yield of 80% was obtained. The refolded protein could not be distinguished from the native lysozyme by activity, compactness, stability, and several spectroscopic measurements. The kinetics of renaturation were then studied by following the reactivation and the changes in fluorescence and circular dichroism signals. When bi- or triphasic sequential models were fitted to the experimental data, the first two phases had the same calculated rate constants for all the signals showing that, within the time resolution of these experiments, the folding/oxidation of hen lysozyme is highly cooperative, with the secondary structure, the tertiary structure, and the integrity of the active site appearing simultaneously.  相似文献   
997.
PURPOSE: Patients frequently have ocular pain, photophobia, foreign-body sensation, and burning/stinging after radial keratotomy. This study was a prospective, randomized, double-masked, multicenter, fellow-eye comparison of diclofenac sodium (Voltaren Ophthalmic, 0.1% solution) and placebo for controlling these ocular symptoms after bilateral radial keratotomy. METHODS: Patients who were pain free in both eyes before surgery were randomly assigned to treatment with diclofenac sodium in one eye and placebo in the other. One drop of each masked trial medication was administered 30-60 min before surgery, 5 min and 6 h after surgery, at bedtime on the day of surgery, and four times daily for 2 additional days. Patients evaluated ocular symptoms in each eye 0.5, 1, 2, 4, 6, 24, and 48 h after surgery and provided a global evaluation 6, 24, and 48 h after surgery. For each assessment, the difference in scores between eyes was analyzed by using a paired t test. RESULTS: Diclofenac sodium was significantly (p < 0.001) superior to placebo in controlling each ocular symptom at each interval after surgery and for patient global assessments 6, 24, and 48 h after surgery. CONCLUSION: Diclofenac sodium 0.1% ophthalmic solution is clinically effective in controlling adverse ocular symptoms occurring after bilateral radial keratotomy.  相似文献   
998.
Cholesterol regulates hepatic 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase activity by feedback inhibition. It has been suggested that oxidized derivatives of cholesterol (oxysterols) play an important role, as an intracellular mediator, in the feedback inhibition of cholesterol biosynthesis. We, therefore, investigated the role of intracellular oxysterols in the regulation of HMG-CoA reductase activity. Rats were fed with food (control), cholesterol, clofibrate as a potentiator of the microsomal monooxygenase cytochrome P-450 enzyme system, ketoconazole as a strong inhibitor of the system, or butylated hydroxytoluene (BHT) as an antioxidant. We analyzed and compared hepatic microsomal oxysterol levels among the groups. The results of this study indicated that the oxysterol level, especially 7beta-hydroxycholesterol and 7-ketocholestrol, in the liver was lowered by the administration of ketoconazole and BHT, and HMG-CoA reductase activity was increased in response to these agents. However, there was no change in the HMG-CoA reductase activity, after the administration of clofibrate. We conclude that reduced levels of oxysterol may release the inhibitory effect on the HMG-CoA reductase enzyme and lead to up-regulation of the enzyme.  相似文献   
999.
In the first large-scale survey on the use of alcohol and tobacco and the inhalation of paint thinner by Japanese high school students, a higher percentage of respondents reported past or regular use of these substances than in a 1978 survey. The survey was conducted in 44 high schools. The 14,438 respondents (ages 15-18 years) represented 9 of Japan's 47 geographically distinct urban and rural prefectures. Most (76%) reported that they had consumed alcohol at some time, and 50% reported drinking on a regular basis. Alcohol consumption, drinking partners, and motivation for drinking were compared by student gender, geographic region, and years of education. Fewer students reported smoking cigarettes: 32% had smoked at some time, and 14% smoked regularly. Inhalation of paint thinner was rare: 3% had purposely inhaled it, and 1% had abused it. A significant percentage of the alcohol drinkers also used tobacco and/or thinner, a tendency that was the same despite differences in gender, grade in high school, and urban or rural geographic region. A tendency toward polysubstance use was evident among these high school students.  相似文献   
1000.
This study examined the contribution of phosphocreatine (PCr) and aerobic metabolism during repeated bouts of sprint exercise. Eight male subjects performed two cycle ergometer sprints separated by 4 min of recovery during two separate main trials. Sprint 1 lasted 30 s during both main trials, whereas sprint 2 lasted either 10 or 30 s. Muscle biopsies were obtained at rest, immediately after the first 30-s sprint, after 3.8 min of recovery, and after the second 10- and 30-s sprints. At the end of sprint 1, PCr was 16.9 +/- 1.4% of the resting value, and muscle pH dropped to 6.69 +/- 0.02. After 3.8 min of recovery, muscle pH remained unchanged (6.80 +/- 0.03), but PCr was resynthesized to 78.7 +/- 3.3% of the resting value. PCr during sprint 2 was almost completely utilized in the first 10 s and remained unchanged thereafter. High correlations were found between the percentage of PCr resynthesis and the percentage recovery of power output and pedaling speed during the initial 10 s of sprint 2 (r = 0.84, P < 0.05 and r = 0.91, P < 0.01). The anaerobic ATP turnover, as calculated from changes in ATP, PCr, and lactate, was 235 +/- 9 mmol/kg dry muscle during the first sprint but was decreased to 139 +/- 7 mmol/kg dry muscle during the second 30-s sprint, mainly as a result of a approximately 45% decrease in glycolysis. Despite this approximately 41% reduction in anaerobic energy, the total work done during the second 30-s sprint was reduced by only approximately 18%. This mismatch between anaerobic energy release and power output during sprint 2 was partly compensated for by an increased contribution of aerobic metabolism, as calculated from the increase in oxygen uptake during sprint 2 (2.68 +/- 0.10 vs. 3.17 +/- 0.13 l/min; sprint 1 vs. sprint 2; P < 0.01). These data suggest that aerobic metabolism provides a significant part (approximately 49%) of the energy during the second sprint, whereas PCr availability is important for high power output during the initial 10 s.  相似文献   
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