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971.
The recording of sounds over the oribt of the eye has been found to be useful in the detection of intracranial aneurysms. A hydrophone for auscultation over the eye has been developed and is tested under controlled conditions. The tests consist of measurement over the eyes in three healthy volunteers at rest, during voluntary breathing, during eyeball movements and during sustained orbicular muscular contractions. Furthermore, measurements are performed at the side of the nose. Major features of the hydrophonic transducer are high sensitivity to physiological sounds and a high degree of insensitivity to environmental sounds propagated through the air. It can be concluded that the hydrophone may be useful for the early detection of intracranial aneurysms and also for apnoea detection.  相似文献   
972.
973.
The effects of three resuscitation fluids, hydroxyethyl starch (HES), Haemaccel, and fresh autologous blood, on reticuloendothelial system phagocytic and catabolic functions and resistance to infection after 40% hemorrhages in BALB/c mice were studied. The mice, anesthetized with isoflurane, were bled over a 10-min period, left hypovolemic for 30 min, and then resuscitated with their shed blood or the same volume of asanguineous fluid. Normothermia was maintained throughout the experiments. The uptake and catabolism of intravenously injected double-labelled sheep erythrocytes (51Cr-125I-SRBC) in liver and spleen were determined at 1 and 48 h after hemorrhage. No significant changes in the uptake or catabolism of SRBC in liver or spleen were found at 1 h after hemorrhage and resuscitation with any of the fluids. However, at 48 h a significant increase in liver uptake of SRBC was seen in animals resuscitated with either Haemaccel or HES compared to that in animals resuscitated with shed blood or in animals subjected to a sham operation. The increase in liver uptake was accompanied by a small decrease in spleen uptake in animals resuscitated with Haemaccel but not with HES. No great changes in catabolic activity were seen at 48 h, although activity levels tended to be higher in animals resuscitated with Haemaccel. Separate groups of animals were challenged by an intraperitoneal injection with live Escherichia coli at 1 or 48 h after hemorrhage and resuscitation. Sixty-four percent of the animals resuscitated with shed blood survived the challenge with E. coli at 1 h after hemorrhage, whereas only 10 and 0% survival was seen for animals resuscitated with Haemaccel and HES, respectively. At 48 h survival was 80% for shed-blood-resuscitated animals and 60 and 70% for Haemaccel- and HES-resuscitated animals, respectively.  相似文献   
974.
Monocytes purified with cell scatter monitored counterflow centrifugation were cultured in plastic (adherent) and in teflon culture bags (suspension). Sequential changes were monitored during 15 days by measuring intracellular activity of three enzymes of intermediary metabolism: glucose-6-phosphate dehydrogenase (G-6-PDH), phosphohexose isomerase (PHI) and isocitrate dehydrogenase (ICDH), and the two acid hydrolases: acid phosphatase (ACP) and N-acetyl-beta-glucosaminidase (NAG). In teflon grown macrophages a significantly lower G-6-PDH activity was seen after 15 days in comparison to plastic adherent macrophages (P less than 0.0002). For the other enzymes similar values for both culture modalities were found. The significantly, cycloheximide insensitive, higher values for G-6-PDH, PHI and ICDH in 2 h plastic adherent monocytes in comparison with plastic non-adherent monocytes, suggest a relationship between adherent capacity and the level of intermediary metabolism. The overall yield of plastic adherent macrophages after 15 days was 35% in contrast with 89% for the in suspension cultured macrophages. This corroborates the existence of adherent and non-adherent monocytes, both capable of differentiation in vitro. In 14 patients with advanced Hodgkin's disease (HD) and 14 normal controls, monocyte differentiation was studied applying both culture modalities. The enzyme levels, reflecting growth and intermediary metabolism, were similar for both groups. The adherent capacity and yield, both in teflon and in plastic, after 15 days was comparable for both groups. It was concluded that in vitro monocyte differentiation in the presence of autologous serum was qualitatively and quantitatively normal in advanced HD; this is in favour of an intrinsically normal function of monocytes in HD.  相似文献   
975.
BACKGROUND: Lipid transfer proteins (LTPs) are small molecules of approximately 10 kD that demonstrate high stability. They have recently been identified as allergens in the Rosaceae subfamilies of the Prunoideae (peach, apricot, plum) and of the Pomoideae (apple). They belong to a family of structurally highly conserved proteins that are also present in non-Rosaceae vegetable foods. OBJECTIVE: The aim of this study was to investigate the cross-reactivity to non-Rosaceae LTPs, and to study the role of protein stability in allergenicity. METHODS: Thirty-eight patients with a positive SPT to Rosaceae fruit extracts enriched for LTP were characterized by interview and SPT. To investigate IgE cross-reactivity between Rosaceae and non-Rosaceae LTPs, RAST and RAST inhibition as well as ELISA and ELISA inhibition were performed, using whole food extracts and purified LTPs. Both purified natural LTPs (peach, carrot and broccoli) and Pichia pastoris recombinant LTPs (carrot and wheat) were included. Pepsin digestion was used to address the role of stability in the allergenicity of LTPs. RESULTS: IgE antibodies to Rosaceae LTPs reacted to a broad range of vegetable foods, including Gramineae (cereals), Leguminosae (peanut), Juglandaceae (walnut), Anacardiaceae (pistachio), Brassicaceae (broccoli), Umbelliferae (carrot, celery), Solanaceae (tomato), Cucurbitaceae (melon), and Actinidiaceae (kiwi). Binding and inhibition studies with purified natural and recombinant LTPs confirmed their role in this cross-reactivity. Many of these cross-reactivities were accompanied by clinical food allergy, frequently including systemic reactions. Antibody binding to LTP was shown to be resistant to pepsin treatment of whole extract or purified LTP. CONCLUSION: LTP is a pan-allergen with a degree of cross-reactivity comparable to profilin. Due to its extreme resistance to pepsin digestion, LTP is a potentially severe food allergen.  相似文献   
976.
OBJECTIVES: To assess the influence of education on the association between apolipoprotein E and cognitive change. DESIGN: Prospective cohort. PARTICIPANTS: HMO-based sample of 2168 non-demented community-dwelling elderly followed over 6 years. MEASUREMENTS: Generalized estimating equations were used with the difference between baseline and follow-up cognitive abilities screening instrument (CASI) as the outcome variable. RESULTS: At follow-up, 6% of the sample had a decline of 1.5 S.D. or greater on the CASI. Compared to individuals without an APOE4 allele, individuals with a single APOE4 allele did not have greater CASI decline. By contrast, individuals with two APOE4 alleles experienced greater decline in cognitive performance and the magnitude of that decline decreased as years of educational attainment increased. These relationships held after adjusting for age, gender, ethnicity, depression, diabetes, and history of vascular disease. CONCLUSION: Lower education was associated with steep 4-year cognitive decline for APOE4 homozygotes but not for APOE4 heterozygotes. Potentially modifiable host factors such as education could influence the association of high-risk genotypes and cognitive decline.  相似文献   
977.
CHROMagar MRSA was evaluated for its ability to identify methicillin-resistant Staphylococcus aureus (MRSA). A well-defined collection consisting of 216 MRSA strains and 241 methicillin-susceptible Staphylococcus aureus isolates was used. The sensitivity of CHROMagar MRSA after 24 h of incubation was 95.4%, increasing to 100% after 48 h. The specificity was already 100% after 24 h.  相似文献   
978.
The Museum Vrolik collection of anatomical specimens in Amsterdam, The Netherlands, comprises over 5,000 specimens of human and animal anatomy, embryology, pathology, and congenital anomalies. Recently, we rediagnosed a subset of the collection comprising dried infantile, juvenile, and adult human skulls with congenital and acquired conditions. On external examination and additional radiography, we found 58 skulls with craniosynostosis (CS) involving one or more sutures and 40 skulls with a presumed suture related condition. Most of these were part of the material collected and described by Louis Bolk (1866-1930). Analysis of his observations suggests that skull deformation because of premature suture closure depends not only on the identity of the sutures involved but also on the timing and progression of their closure and the extent of their involvement. Moreover, premature closure of the sagittal suture after 3-6 years of age appeared to be much more common than expected because it is not accompanied by skull deformation. Many of the skulls with single-suture CS were microcephalic, which may be the cause of the premature synostosis. By contrast, microcephaly may be a resulting phenomenon in multi-suture CS. We noticed that the quotient between height of the cranial vault (vertex-porion distance) and head circumference, multiplied by 100, was 26 or higher only in those CS cases with multi-suture involvement. We therefore consider this parameter, which we named "acrocephalic index", to be an indicator of multi-suture involvement in individual CS cases. In two adult skulls, the skull had a quadrangular shape, which we assumed to be correlated to the presence of an unusually interdigitated open metopic suture. We propose to name this anomaly: tetragonocephaly. Another presumed suture-related condition, bathrocephaly, was found concomitantly with basilar invagination in several cases. We hypothesize that the chronically raised intracranial pressure in these cases caused the still open lambdoidal sutures to distend and the occipital bone to protrude.  相似文献   
979.
In the present study, serotonin (5-HT) responses of hippocampal pyramidal cornu ammonis 1 (CA1) neurons were studied in rats subjected twice daily for 21 days to unpredictable stressors. In hippocampal tissue from thus stressed rats mRNA expression of the 5-HT(1A) receptor and mineralo- as well as glucocorticoid receptors were examined with in situ hybridization. On average, stressed rats displayed increased adrenal weight and attenuated body weight gain compared with controls, supporting that the animals had experienced increased corticosterone levels due to the stress exposure. One day after the last stressor, under conditions that corticosterone levels were low (predominant mineralocorticoid receptor activation), the 5-HT(1A) receptor mediated hyperpolarization of CA1 neurons in response to 10 microM 5-HT was significantly reduced compared with controls. Basal membrane properties of CA1 cells in stressed rats were comparable to those of controls. The 5-HT(1A) receptor mRNA expression was not changed after chronic stress exposure, in any of the hippocampal areas. A small but significant increase in mineralocorticoid receptor mRNA expression was observed after stress in the dentate gyrus, while glucocorticoid receptor expression was unchanged. The data indicate that unpredictable stress exposure for 3 weeks results in suppression of 5-HT(1A) receptor-mediated responses, possibly due to posttranslational modification of the receptor.  相似文献   
980.
Many biochemical, physiological, and behavioral processes display daily rhythms generated by an internal timekeeping mechanism referred to as the circadian clock. The core oscillator driving this clock is located in the ventral part of the hypothalamus, the so called suprachiasmatic nuclei (SCN). At the molecular level, this oscillator is thought to be composed of interlocking autoregulatory feedback loops involving a set of clock genes. Among the components driving the mammalian circadian clock are the Period 1 and 2 (mPer1 and mPer2) and Cryptochrome 1 and 2 (mCry1 and mCry2) genes. A mutation in the mPer2 gene leads to a gradual loss of circadian rhythmicity in mice kept in constant darkness (DD). Here we show that inactivation of the mCry2 gene in mPer2 mutant mice restores circadian rhythmicity and normal clock gene expression patterns. Thus, mCry2 can act as a nonallelic suppressor of mPer2, which points to direct or indirect interactions of PER2 and CRY2 proteins. In marked contrast, inactivation of mCry1 in mPer2 mutant mice does not restore circadian rhythmicity but instead results in complete behavioral arrhythmicity in DD, indicating different effects of mCry1 and mCry2 in the clock mechanism  相似文献   
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