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991.
Summary. The L1 capsid proteins derived from human papillomavirus (HPV) type 33 were expressed in a recombinant baculovirus system using Sf9 insect cells. Selected sera originating in women from case-control study carried out in Spain and Colombia found negative and positive for HPV16, 18, 31, 33 and 35 DNA were tested in ELISA for the presence of IgG antibodies to purified virus-like particles (VLP). The reactivity was type-restricted with the possible exception of HPV31. Received July 4, 1996 Accepted September 17, 1996  相似文献   
992.
A primary care version of the International classification of diseases (10th revision) chapter five for mental and behavioural disorders (ICD-10 PHC chapter five) has been developed. This provisional version focuses on 24 conditions which are frequently seen in primary care and which can be managed effectively by general practitioners. The classification is accompanied by a flipcard for each of the conditions. The cards have diagnostic guidelines on one side and management guidelines on the other. The latter provide information which should be given to the patient, advice on the content of counselling, the available treatment methods, and indications for specialist referral. This classification system is also supported by diagnostic decision making aids, medication cards, and patient leaflets to facilitate the recognition and management of patients with mental disorders in primary care settings. The draft version of ICD-10 PHC chapter five will be finalized after field trials which will test the applicability and usefulness of the system in different primary care settings in various countries.  相似文献   
993.
An Echinococcus granulosus genomic library has been screened with a mouse β-actin cDNA probe. Two clones carrying DNA fragments of about 15 kb, possibly derived from the same genome region, have been isolated. This 15-kb genomic region includes 2 actin-related sequences (EgactI and EgactII) separated by about 4 kb. The nucleotide sequences of both genes were determined. The EgactI sequence presents no introns, but an intron of 591 bp was observed in the EgactII sequence. The genes potentially encode 375 and 376 amino-acid-long actins, respectively, with a homology of 85.3%. The deduced amino acid sequences from both genes were compared to the actin sequences from other organisms, showing similarities ranging from 63.5% to 90.6%. The nucleotide sequence of a partial actin cDNA clone has been determined. The deduced amino acids sequence showed a homology of 90.3% and 88.0% in relation to the EgactI and EgactII sequences respectively, suggesting the existence of at least one more actin gene in E. granulosus. This hypothesis is reinforced by the number of bands detected in the Southern blot analysis. Experiments based on the amplification of DNA segments using 3′-specific actin primers indicate that the EgactI gene is transcribed in protoscoleces.  相似文献   
994.
The calcium ionophore A23187 and anti-human IgE provoked a dose-dependent release of histamine and cysteinyl-leukotrienes (LTC4, LTD4 and LTE4) from dispersed human lung cells. Optimal release of histamine peaked at 3 min after challenge whereas the release of cysteinyl-leukotrienes peaked at 30 min. The molar ratio between released histamine and cysteinyl-leukotrienes was approximately 1001. The ionophore, but not anti-IgE caused additional formation of LTB4 in the dispersed cells or the chopped lung, indicating that this chemoattractant is formed from cells not primarily activated by IgE-dependent mechanisms. Indomethacin failed to alter release of histamine or leukotrienes from dispersed cells, whereas further inhibition of lipoxygenases by NDGA abolished leukotriene formation and reduced the release of histamine.  相似文献   
995.
No standardized method for susceptibility testing of Brachyspira spp. is currently available. A broth dilution procedure was evaluated and used to test the activities of six antimicrobial agents for 108 isolates of Swedish porcine Brachyspira spp. representing biochemical groups I, II, and III. Group I corresponds to Brachyspira hyodysenteriae, group II corresponds to B. intermedia, and group III corresponds to B. murdochii and B. innocens. A panel was designed with the antimicrobial agents dried in tissue culture trays with wells that allowed a liquid volume of 0.5 ml in each and agitation of the broth when incubated on a shaker. The MICs were determined by using brain heart infusion broth with 10% fetal calf serum. For 10 isolates, the results obtained in broth were compared to the MICs obtained on two different types of agar. Different inoculum densities and incubation times were also compared. The concentrations at which 90% of the B. hyodysenteriae isolates (n = 72) were inhibited in the broth dilution test by tiamulin (0.25 micro g/ml), tylosin (>256 micro g/ml), erythromycin (>256 micro g/ml), clindamycin (>4 micro g/ml), virginiamycin (4 micro g/ml), and carbadox (0.06 micro g/ml) were determined. The MICs tended to be lower in broth than on agar. Differences in inoculum densities and incubation times had little influence on the MICs. The evaluated broth dilution test was simple to perform, the end points were easily read, and the results were reproducible and reliable. No isolates with decreased susceptibility to tiamulin were found among the Swedish isolates tested.  相似文献   
996.
BACKGROUND: Recent reports have suggested that ultrasound (US) guidance during embryo transfer might improve pregnancy rates. METHODS: A prospective randomized (computer-generated random table) trial was performed to compare embryo transfer under abdominal US guidance (n = 255 women) with clinical touch embryo transfer (n = 260). RESULTS: The clinical pregnancy rate was 26.3% (67/255) in the US-guided transfer group compared with 18.1% (47/260) in the clinical touch transfer group (P < 0.05). The implantation rate was 11.1% (100/903) in the US group compared with 7.5% (66/884) in the clinical touch group (P < 0.05). US-guided transfer was associated with a decrease in the difficulty of the transfers: 97% of transfers were easy in the US-guided group compared with 81% in the clinical touch group (P < 0.05). CONCLUSIONS: US-guided embryo transfer increased pregnancy and implantation rates in IVF cycles, as well as the frequency of easy transfers. It is suggested that the decrease in cervical and uterine trauma can play a role in the increase in pregnancy rates associated with US-guided transfer. It is recommended that embryo transfer should be performed under US guidance.  相似文献   
997.
Summary.  BCH4 cells, persistently infected with Human Respiratory Syncytial Virus (HRSV), were obtained by Fernie et al. [12] after infection of a BALB/c mouse embryo cell line with the Long strain of HRSV. To understand the basis of HRSV persistence, the expression of HRSV RNAs and proteins was evaluated in BCH4 cells and infected parental BALB/c and fully permissive HEp-2 cells. Production of viral mRNAs was severely impaired in BCH4 cells. In addition, the expression level of the surface glycoproteins F and G was markedly reduced relative to internal viral proteins. However, virus recovered from BCH4 cells could lytically infect HEp-2 cells and expressed normal levels of surface glycoproteins. No evidence of defective genomes or interfering particles was found in BCH4 cells. Taken together, these data indicate that reduction of both viral mRNA accumulation and surface glycoprotein biosynthesis are at the basis of HRSV persistence in BCH4 cells. Accepted November 3, 2000  相似文献   
998.
Monocyte-derived dendritic cells (mDC) are increasingly used as cancer vaccines. However, human monocytes are a heterogeneous cell population. We showed previously that DC derived from a monocyte subset expressing CD16 (16+mDC) stimulated allogeneic naïve T lymphocytes to secrete higher levels of IL-4 than DC derived from regular CD14highCD16? monocytes (16?mDC). Th1-type responses have been associated with effective antitumor responses, thus the use of mDC containing 16+mDC as cancer vaccines might be disadvantageous. Here, we evaluate the primary and memory immune response elicited in vitro by 16+mDC and 16?mDC in five patients with metastatic renal cell carcinoma vaccinated with autologous mDC pulsed with tumor lysates (TuLy) and keyhole limpet hemocyanin (KLH). After therapy, three of the five patients had stable disease. Surprisingly, patients with longer survival showed the highest amount of peripheral blood CD16+ monocytes. Analysis of KLH-specific antibodies revealed high titers of IgG2 in patients with longer survival. CD4+ T lymphocyte proliferation against KLH and TuLy increased after treatment, and some patients showed an augmented rate of CD4+ T lymphocyte proliferation against KLH (3/5) and TuLy (2/3) when 16+mDC were used as antigen presenting cells (APC). Before treatment, the IFN-γ/IL-4 ratio against TuLy and KLH was higher when using 16?mDC as APC, but after vaccination four of five patients had an increased ratio for TuLy with 16+mDC. These results suggest that the immune response elicited by 16?mDC and 16+mDC is modified when memory or naïve T cells are stimulated, and 16+mDC could favor a stronger and more beneficial antitumoral Th1 memory response in vivo.  相似文献   
999.
Familial amyloid polyneuropathy (FAP) is characterized by deposition of mutated transthyretin (TTR) in the peripheral nervous system. Prior to amyloid fibrils, nonfibrillar TTR aggregates are deposited inducing oxidative stress with increased nitration (3-NT). As the major source of TTR is the liver, liver transplantation (LT) is used to halt FAP. Given the shortage of liver donors, domino LT (DLT) using FAP livers is performed. The correlation between TTR deposition in the skin and nerve was tested in biopsies from normal individuals, asymptomatic carriers (FAP 0) and FAP patients; in FAP 0, nonfibrillar TTR was observed both in the skin and nerve in the same individuals; in patients, amyloid was detected in both tissues. The occurrence of amyloidosis in recipients of FAP livers was evaluated 1-7 years after DLT: TTR deposition occurred in the skin 3 years after transplantation either as amyloid or aggregates; in one of the recipients, fibrillar TTR was present in the epineurium 6 years after DLT. Deposits were scarce and 3-NT immunostaining was irrelevant. Nerve biopsies from DLT recipients had no FAP-related neuropathy. Our findings suggest that TTR amyloid formation occurs faster than predicted and that TTR of liver origin can cross the blood-nerve barrier. Recipients of FAP livers should be under surveillance for TTR deposition and tissue damage.  相似文献   
1000.
B cell neoplasms present heterogeneous patterns of lymphoid organ involvement, which may be a result of the differential expression of chemokine receptors. We found that chemokine receptor (CCR)7, CXC chemokine receptor (CXCR)4, or CXCR5, the main chemokine receptors that mediate B cell entry into secondary lymphoid tissues and their homing to T cell and B cell zones therein, were highly expressed in B malignancies with widespread involvement of lymph nodes. Conversely, those pathologies with little or no nodular dissemination showed no expression to very low levels of CCR7 and CXCR5 and low to moderate levels of CXCR4. These findings provide evidence for the role of CCR7, CXCR4, and CXCR5 in determining the pattern of lymphoid organ involvement of B tumors. Functional studies were performed on B malignancies expressing different levels of CCR7, CXCR5, and CXCR4. Multiple myeloma (MM) cells did not express CCR7 nor CXCR5 and did not migrate in response to their ligands; a moderate expression of CXCR4 on MM cells was accompanied by a migratory response to its ligand, CXCL12. By contrast, cells from B cell chronic lymphocytic leukemia (B-CLL) expressed the highest levels of these chemokine receptors and efficiently migrated in response to all ligands of CCR7, CXCR4, and CXCR5. In addition, the migration index of B-CLL cells in response to both of the CCR7 ligands correlated with the presence of clinical lymphadenopathy, thus indicating that the high expression of functional chemokine receptors justifies the widespread character of B-CLL, representing a clinical target for the control of tumor cell dissemination.  相似文献   
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