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51.
The ability of 111 Streptococcus agalactiae strains to bind to human fibrinogen was quantified. We correlated the percentages of bacteria that bound to immobilized fibrinogen with fibrinogen-binding (fbs) gene characteristics of strains and with clinical origin, serotypes, and phylogenetic positions of strains. Percentages varied from 0.4 to 29.9%. Fifty-five strains (49.5%) had the fbsB gene sensu stricto described by Gutekunst et al. (Infect. Immun., 72:3495-3504, 2004), allowing adhesion to human fibrinogen, and all of the other strains had an fgag variant gene. Ninety strains (81.1%) had a fbsA gene and 55 of them also had the fbsB gene. The other 21 strains (18.9%) had a truncated form of fbsA without the fbsB gene sensu stricto. The numbers of 48-nucleotide repeat sequences (rs) in the fbsA gene varied from 2 to 26. The population of strains with the highest ability to bind to human fibrinogen significantly more frequently had the fbsB gene sensu stricto and 4 to 7 rs in the fbsA gene (P < 0.05). However, the single strain that carried the highest number of rs (26 rs) in the fbsA gene showed high fibrinogen-binding activity (24.3%). Strains exhibiting significantly higher levels of binding to human fibrinogen belonged to a phylogenetic group of strains associated with neonatal meningitis, currently known as the ST-17 clone, that is mostly composed of serotype III strains. These findings indicate that S. agalactiae strains possess a wide variety of fbs gene content that markedly influences the ability of strains to bind to human fibrinogen. Variations in the configuration and the expression of the Fbs proteins may therefore partly explain the variability of virulence in S. agalactiae species.  相似文献   
52.
While myelin-reactive T cells are widely believed to play a pathogenic role in multiple sclerosis (MS), no substantial differences appear to exist in T-cell responses to myelin antigens between MS patients and healthy subjects. As an example, indistinguishable peripheral T-cell responses and serum antibody levels have been found in MS patients and healthy controls to alpha B-crystallin, a dominant antigen in MS-affected brain myelin. This suggests that additional factors are relevant in allowing myelin-reactive T cells to become pathogenic. In this study, we examined whether the inflammatory state of the CNS is relevant to the pathogenicity of alpha B-crystallin-specific T cells in mice. In normal mice, T-cell responses against alpha B-crystallin are limited by robust immunological tolerance. Reactive T cells were therefore generated in alpha B-crystallin-deficient mice, and these T cells were transferred into C57BL/6 recipients. While such a transfer in itself never induced any clinical signs of experimental autoimmune encephalomyelitis (EAE) in healthy recipient mice, acute EAE could be induced in animals that had been infected 7 days before with the avirulent A7(74) strain of Semliki Forest virus (SFV). SFV infection alone did not induce clinical disease, nor did it alter the expression levels of the target antigen. Our findings indicate that at least in mice, alpha B-crystallin-specific T cells can trigger EAE but only when prior viral infection has induced an inflammatory state in the CNS that helps recruit and activate T cells.  相似文献   
53.
Myelin oligodendrocyte glycoprotein (MOG), a minor protein of the central nervous system myelin, is recognized as a potential target in multiple sclerosis and neuromyelitis optica. The extracellular domain of MOG is commonly used in a wide range of mouse strains and other animals to induce experimental autoimmune encephalomyelitis (EAE), an autoimmune animal model of multiple sclerosis, because it is a target for antibody‐mediated attack. Previous studies, using selected peptides, have indicated that MOG35–55 peptide is an encephalitogenic epitope in C57BL/6 (H‐2b) mice. A more systematic analysis of both T‐cell and B‐cell responses following immunization of C57BL/6 mice with either recombinant extracellular mouse MOG protein (1–116) or with overlapping peptides spanning the whole sequence of MOG, before assessment of responses to 15 mer and 23 mer peptides was undertaken. The studies identified T‐cell responses within the MOG35–55 (extracellular domain) but also two new immunogenic and encephalitogenic T‐cell epitopes within residues MOG113–127, MOG120–134 (localized in the transmembrane region) and MOG183–197 (in the second hydrophobic MOG domain). In addition, residue MOG113–127 was found to be a B‐cell epitope, suggesting that this may be a useful adjunct for the induction of EAE as well as for immunological studies in C57BL/6 mice, which are increasingly being used to study immune function through the use of transgenic and gene knockout technology.  相似文献   
54.
In this study we have examined 32 patients with Beckwith Wiedemann Syndrome (BWS) for mutations affecting the CDKN1C gene, including seven cases of familial BWS. Mutations were not detected in the coding region of the CDKN1C gene in any individual with BWS. However in two patients, two G/A base substitutions at adjacent positions in the 5'UTR were detected. These substitutions were also found in normal controls. Expression of CDKN1C in somatic tissues was examined in 18 of the 32 cases using semi-quantitative RT-PCR. CDKN1C expression was significantly reduced in the peripheral blood of three cases compared with controls. These results suggest that, although coding region mutations in the CDKN1C gene are rare in BWS, mutations disrupting CDKN1C expression may be found. Three of five informative patients exhibited biallelic CDKN1C expression in lymphocytes, cord blood, and kidney tissue, respectively. Biallelic expression was not associated with overall CDKN1C levels significantly different to those in controls. Patients who expressed CDKN1C biallelically, or who were low CDKN1C expressors, maintained monoallelic methylation in the Differentially Methylated Region 2 (DMR2) of the IGF2 locus. One patient expressing CDKN1C biallelically, maintained imprinted gene expression at the IGF2 locus. These results suggest that biallelic CDKN1C expression does not significantly perturb the overall levels of CDKN1C expression in somatic tissue. They also confirm other studies showing that the mechanisms associated with regulating CDKN1C expression and imprinting are separate from those regulating IGF2 imprinting.  相似文献   
55.
Adnexal torsion is a condition that may result in serious consequences, including adnexa removal. Recently, de-torsion has replaced salpingo-oophorectomy as the treatment for a twisted ischaemic adnexum, and the best way to do it seems to be laparoscopic surgery. A case of adnexal torsion caused by a giant para-ovarian cyst treated, with good results, by a conservative laparoscopic approach is reported.  相似文献   
56.
OBJECTIVES: To forecast, on the basis of the past and present position of rheumatologists in Europe, the competence needed in the future to secure and promote the specialty within the healthcare network. METHODS: Union Européenne des Médecins Spécialistes/European Board of Rheumatology (UEMS/EBR) questionnaire on (a) training centres in Europe, (b) rheumatologists' skills, (c) UEMS core curriculum. RESULTS: 173 training centres in rheumatology were identified. Reponses to the questionnaire showed both harmony and diversity in the practice of rheumatology. Harmony arises from the need to (a) have an extensive and profound knowledge of, and clinical experience with, all the causes of painful or disabled locomotor apparatus; (b) manage such disorders in the most cost effective way; and (c) promote "shared clinical decision making". The diversity seen both among and within the European countries is due to the different activities of rheumatologists. CONCLUSION: Rheumatological competence must be based on a common core, as described in the UEMS core curriculum, and on deeper and diverse clinical or scientific knowledge covering the entire field of the specialty, to secure its flexibility and resilience in the market place and to promote its scientific development.  相似文献   
57.
Basing themselves on a series of twelve cases of cervicofacial cylindromas, the authors review the different clinical data pertaining to the evolution of these tumors, which they find to be prevalent in females aged around sixty. Cylindromas predominantly occur in the submandibular and accessory salivary glands. Out of twelve cases, the report mentions three local recurrences and two pulmonary metastases. Management was surgical in all instances.  相似文献   
58.
Lateral cysts and fistulas of the neck are branchial cleft malformations. Lateral fistulas occurring at the basis of the neck account for about 5% of all congenital neck fistulas. Concerning 18 personal case observations of 2nd and 3rd branchial arch cysts, the authors report the chief clinical findings in this type of malformation, as well as discussing fistulography as a valuable investigational technique. They present the characteristics of surgical therapy as the sole possible solution.  相似文献   
59.
Amniotic band syndrome is a rare fetal malformation involving limb ring strictions, cranio-facial and trunck abnormalities. The authors report a case of 5 months old infant with also facial cleft. The plastic reconstructive surgery leads to a better functional result. This affection represents a sporadic disease without genetic causes. The pregnancy ultrasonography visualise fetal abnormalities.  相似文献   
60.
To assess the safety and accuracy of the Camino intraparenchymal sensor, we prospectively evaluated hemorrhagic complications, zero-drift, infection, and system malfunction in 163 patients monitored after a severe head injury. Mean duration of intracranial pressure (ICP) monitoring was 5 +/- 2.2 days (range: 12 h to 11 days). Of the 141 patients with a control CT scan, four showed a 1-2-cc collection of blood at the catheter's end. When removed, the sensors underread the true ICP value (negative zero-drift) in 80 of the 126 sensors evaluated (63.5%). Fourteen sensors showed no zero-drift, and 32 sensors overread the true ICP value (positive zero-drift) (median: -1 mm Hg; interquartile range: -4 to +1 mm Hg). No significant relationship was found between zero-drift, the surgeon who implanted the sensor, intracranial hypertension, or duration of ICP monitoring. No clinical infections could be attributed to the devices. Sixteen patients (9.8%) required more than one ICP sensor due to malfunctioning of the system. In conclusion, continuous ICP monitoring using the Camino intraparenchymal sensor has a low complication rate. However, this sensor may underread the real ICP values in a high number of patients. The lack of correlation between duration of ICP monitoring and zero-drift suggests that, contrary to the recommendations of other reports, the intraparenchymatous Camino sensor can provide reliable readings after the fifth day of use.  相似文献   
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