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71.
Innate immunity against microbial pathogens relies on the pattern recognition of cell wall components on invading microbes. Recent evidence has shown that a mammalian Toll-like receptor (TLR) is activated by bacterial lipopolysaccharides (LPS). The innate immunity in invertebrates is also triggered by LPS, as seen in the hemolymph coagulation in horseshoe crab. We report the cloning of a TLR from the Japanese horseshoe crab Tachypleus tridentatus. A cDNA coding for Tachypleus Toll was isolated from a hemocyte cDNA library and the open reading frame codes for a proprotein including a signal sequence. Like Drosophila Toll, Tachypleus Toll is a type I transmembrane protein with an extracellular domain consisting of two leucine-rich repeats flanked by two cystein-rich clusters and a cytoplasmic domain exhibiting striking similarity with the cytoplasmic domain of interleukin-1 receptor. Tachypleus Toll is most similar to Drosophila Toll in the domain architecture and the overall length.  相似文献   
72.
Over the past few decades, many researchers have individually identified tumor-related genes, and have accumulated information on their basic research in a database. With the development of technology that can comprehensively test the expression status within a short time, oncogene panel testing has become attainable. On the other hand, changes in gene expression that do not depend on changes in base sequences, that is, epigenetics, or more comprehensively, epigenomes, are also highly involved in the development and progression of disease. Oncogene panel tests tend to focus on DNA base mutations such as point mutations, deletions, duplications, and chimera formation. Elucidation leads to correct interpretation of diseases and treatment choices, and we are in an era where integrated understanding of the genome and epigenome is indispensable. In this review, we make every effort to cover a wide range of knowledge, including data on histone protein modification, non-coding (nc)RNA and DNA methylation, and recent application trials for demonstrating epigenetic alterations in histologic and cytologic specimens. We hope this review will help marshal the knowledge accumulated by researchers involved in genomic and epigenomic studies.  相似文献   
73.
Hepatitis?B virus (HBV) infection is highly endemic in the Solomon Islands. However, little is known about the status of occult HBV infection in the Solomon Islands. This study aimed to investigate the prevalence of occult HBV infection and its clinical and virological features in the community of Solomon Islands. Blood samples were collected from a total of 564 asymptomatic individuals aged over 18 years in the Western province. The samples used in the present study consisted of 200 samples from 108 males and 92 females (mean age, 37.4 years; range, 18-71 years) that were randomly selected among the hepatitis?B surface antigen (HBsAg)-negative samples from all the participants enrolled in this study. HBV-DNA was detected by real-time?PCR in 25 (12.5%) of the 200 HBsAg-negative samples. Most of the HBV-DNA-positive individuals were infected with wild-type HBV, and only 3 strains demonstrated specific amino acid substitutions (P121X, T123N, C138S, P142S and D144E) in the α?determinant region. In conclusion, occult HBV infection was documented in 12.5% of individuals that demonstrated serologic evidence of resolved HBV infection in this study. The prevalence of occult infection was also influenced by ethnicity; it was more prevalent in Melanesians than Micronesians. In addition, occult HBV infection demonstrated a weak association with the S-variants.  相似文献   
74.
Two 20-membered macrolides, iriomoteolides-1b ( 1) and -1c ( 2), have been isolated from a marine dinoflagellate Amphidinium sp. (strain HYA024), and the structures were elucidated on the basis of detailed analyses of 2D NMR data and chemical correlation.  相似文献   
75.
76.
A 4-year-old boy with atrioventricular discordance, double-outlet right ventricle, pulmonary stenosis, and mitral regurgitation, was undergoing anatomical repair consisting of Senning, Rastelli, Damus–Kaye–Stansel procedures, and a mitral valve repair, complained of post-operative excessive airway tract secretion, which ultimately developed into acute respiratory distress syndrome (ARDS) 28 days after the operation. The cause of the ARDS was thought to be frequent manual positive pressure recruitment and prolonged inhalation of pure oxygen. At 45 days after the operation, hypercapnia and respiratory acidosis turned out to be irreversible, and therefore, veno-arterial extracorporeal membrane oxygenation (ECMO) was established utilizing the Endumo®4000 system. Pulmonic interstitial inflammation gradually improved while resting the lung under ECMO support; however, effective ventilation volume decreased critically because a massive pulmonary hemorrhage occurred at 2 and 9 days after the initiation of ECMO. To maximize the effectiveness of respiratory physical therapy, “Awake ECMO” was started and tidal volume dramatically increased with a regained cough reflex. Five days later, he was successfully weaned off from ECMO, and discharged 7 months after the operation without any neurological and physiological sequelae.  相似文献   
77.
Objectives: To clarify the clinical risk factors associated with poor neonatal outcomes due to umbilical cord prolapse (UCP).

Methods: A postal questionnaire survey was attempted in Japan. The clinical risk factors and managements associated with poor neonatal outcomes were analyzed in cases of UCP treated in Japan.

Results: A total of 267 cases of UCP (out of 2?037?460 total deliveries) were analyzed. The rates of intrauterine death, neonatal death and survival with disability were 3.4%, 5.6% and 7.1%, respectively. The multivariate regression analysis for these poor neonatal outcomes revealed that the significant risk factors included a prolapsed amniotic sac (adjusted odds ratio (aOR), 4.49), preterm labor (aOR, 2.99) and replacement of the prolapsed umbilical cord into the uterus (aOR, 2.87). However, UCP that occurred during labor (aOR, 0.28) and emergency cesarean section (aOR, 0.11) were associated with a reduction in the rates of poor outcomes. The interval between the diagnosis of UCP and delivery was significantly longer in the infants with a poor outcome than intact survival (median 30 versus 24?min, p?=?0.048).

Conclusion: An emergency cesarean section should be carried out immediately to ensure a better outcome for the infant.  相似文献   
78.
Streptococcus pyogenes thiol proteinase, also known as streptococcal pyrogenic exotoxin B (SpeB), has been suggested to be a major virulence factor in S. pyogenes infection. SpeB was reported to induce apoptosis of host cells, but its mechanism of action is not yet fully understood. In this study, we examined the involvement of matrix metalloproteinases (MMPs) in SpeB-induced apoptosis. We first developed a large-scale preparation of recombinant SpeB and precursors of human MMP-9 and -2 (proMMPs) by using Escherichia coli Rosetta (DE3)pLysS and baculovirus-insect cell expression systems, respectively. Treatment with SpeB induced effective proteolytic activation of both proMMP-9 and -2. When RAW264 murine macrophages were incubated with SpeB-activated proMMP-9, the level of tumor necrosis factor alpha (TNF-alpha) in conditioned medium (CM), assessed by an enzyme immunoassay, was elevated. This increase was completely inhibited by addition of the MMP inhibitor SI-27 to the cell culture. The CM also produced marked induction of apoptosis of U937 human monocytic cells. Similarly, soluble Fas ligand (sFasL) was detected in CM of cultures of SW480 cells expressing FasL after treatment with SpeB-activated proMMPs; this CM also induced apoptosis in U937 cells. SpeB had a direct effect as well and caused the release of TNF-alpha and sFasL from the cells. SpeB-dependent production of MMP-9 and -2 and proapoptotic molecules (TNF-alpha and sFasL) was evident in a murine model of severe invasive S. pyogenes infection. These results suggest that SpeB or SpeB-activated MMPs contribute to tissue damage and streptococcal invasion in the host via extracellular release of TNF-alpha and sFasL.  相似文献   
79.
80.
We cultivated kidney hematopoietic cells from clonal triploid ginbuna crucian carp, Carassius auratus langsdorfii. Proliferating cells from hematopoietic cell cultures were harvested and injected into tetraploid hybrids (clonal triploid ginbuna and goldfish hybrid) which possess three sets of chromosomes from a triploid clone and a haploid set of chromosomes from goldfish (Carassius auratus). After injection of cultured triploid cells (donor cells), blood samples were obtained from tetraploid hybrids (recipients) every other week. Blood cells stained with acridine orange were measured by flow cytometry to trace the injected donor cells by means of differences in DNA content. Although erythrocytes were not produced in donor cell cultures, such cultures maintained precursor cells capable of differentiation into erythrocytes in vivo. After 4-12 weeks of transplantation, mature erythrocytes derived from the donors were observed in the blood circulation of the recipient fish. These results indicated that the ginbuna hematopoietic cell culture system is an in vivo situation suitable for the study of hematopoietic control mechanisms.  相似文献   
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