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991.
The p53 gene (TP53) is mutated in numerous human cancers. We have used it as a molecular target to characterize the induction of mutations in human skin cancers. About 50% of all skin cancers in normal individuals exhibit p53 mutations. This frequency rises to 90% in skin cancers of patients with the DNA-repair deficiency known as xeroderma pigmentosum (XP). These mutations are characterized by a specific signature, attributed to the ultraviolet uvB part of the solar spectrum. In this review, we will describe different p53 mutation spectra, in relation to the various histopathological types of skin cancers such as basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and malignant melanoma as well as to the DNA repair efficiency of the patients. In particular, different mutational hot spots are found among the various spectra. We have tried to elucidate them in terms of induced DNA lesion hot spots, as well as speed of local nucleotide excision repair (NER) or sequence effects. The molecular analysis of these mutagenic characteristics should help in the understanding of the origin of human skin cancers in the general population. 相似文献
992.
Molecular characterization of isolates of waterborne Cryptosporidium spp. collected during an outbreak of gastroenteritis in South Burgundy,France
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Dalle F Roz P Dautin G Di-Palma M Kohli E Sire-Bidault C Fleischmann MG Gallay A Carbonel S Bon F Tillier C Beaudeau P Bonnin A 《Journal of clinical microbiology》2003,41(6):2690-2693
In September 2001, a waterborne outbreak of gastroenteritis occurred in eastern France. Of 31 fecal samples from symptomatic individuals, 19 tested positive for Cryptosporidium with two PCRs targeting the Hsp70 and the 18S rRNA genes of CRYPTOSPORIDIUM: Sequencing of the PCR fragments produced sequences identical to that of Cryptosporidium parvum genotype 1. 相似文献
993.
Schleiermacher G Janoueix-Lerosey I Combaret V Derré J Couturier J Aurias A Delattre O 《Cancer Genetics and Cytogenetics》2003,141(1):32-42
Neuroblastoma is characterized by several distinct genetic alterations including MYCN amplification, chromosome 1p deletion and gain of chromosome 17. Although these alterations are thought to play a crucial role in oncogenesis, to date little is known about their underlying mechanisms. In order to more precisely document these genetic alterations, we have performed a combined study of 27 neuroblastoma cell lines using 24-color karyotyping (24-CK) and comparative genomic hybridization (CGH). 24-CK detected balanced translocations in 13 cases with recurrent involvement of chromosome 8. More importantly, 144 nonreciprocal translocations were observed in the 27 cell lines, with chromosome 1 as the most frequent recipient and chromosome 17 the most frequent donor. Each cell line exhibited at least one unbalanced translocation involving 17q, with 14 cell lines demonstrating more than one such translocation. Other recurrent alterations were amplification of the 2p24 chromosome region, which encodes the MYCN oncogene, losses of 1p, 3p and 11q, and gains of 1q and 7. In most cases, CGH profiles were directly linked to the presence of unbalanced translocations with gain of the donor fragment and loss of the replaced region on the recipient chromosome. Strikingly, over 60% of the chromosome breakpoints mapped to early replicating chromosome bands, which represent around 13% of the genome. Altogether these data suggest that neuroblastoma is characterized by rearrangements that predominantly involve chromosome fragments replicating early in the S-phase. 相似文献
994.
995.
OBJECTIVE: The purpose of this study was to evaluate the long-term efficiency after abdominal sacrohysteropexy in women with uterovaginal prolapse. STUDY DESIGN: We conducted a retrospective chart review at our tertiary referral urogynecology unit. Thirty women of childbearing age with uterovaginal prolapse who wanted uterine preservation underwent abdominal sacrohysteropexy between 1987 and 1999. RESULTS: The mean age of the women was 35.7 years (range, 29-43 years). All women were parous. Thirteen women had grade 2 uterovaginal prolapse, and 17 women had grade 3 prolapse. In all women, the Burch procedure and posterior colporrhaphy were performed at the same time. Intraoperative and postoperative complications occurred in 2 patients (6.6%) and 4 patients (13.3%), respectively. The mean objective and subjective follow-up periods were 44.5 months (range, 2-156 months) and 94.6 months (range, 8-160 months), respectively. At the time of the last physical examination, there were two cases of recurrent uterovaginal prolapse (6.6%), which was symptomatic in 1 patient and required repeat surgical treatment. At the time of the last questionnaire, apart from the patient who underwent repeat surgery, no patients had any uterovaginal prolapse symptoms. Three women had pregnancies that were conceived spontaneously, which led to three early legal abortions. CONCLUSION: The abdominal sacrohysteropexy is effective and safe in the treatment of uterovaginal prolapse in women of childbearing age. This procedure has a high success rate in correcting prolapse without a time-dependent decrease in efficiency. 相似文献
996.
997.
Bétrémieux P Lionnais S Beuchée A Pladys P Le Bouar G Pasquier L Loeuillet-Olivo L Azzis O Milon J Wodey E Frémond B Odent S Poulain P 《Prenatal diagnosis》2002,22(11):988-994
OBJECTIVES: To assess the prognosis of prenatally diagnosed congenital diaphragmatic hernia (CDH) during the years 1995-2000 in order to improve prenatal counselling. METHODS: Retrospective study of all 31 cases of women with prenatally diagnosed CDH. RESULTS: Nine pregnancies (29%) were terminated and two fetuses (6%) were stillborn. Ten fetuses (32%) had associated anomalies (four Fryns' syndrome) and four (13%) had underlying chromosomal anomalies. Twenty pregnancies were continued. Seven babies died before surgery either immediately in the delivery room (five between 1 and 45 min), or during the 'stabilisation period' (two babies, 7 and 21 h). Three babies presented with trisomy 18, Fryns' syndrome or transposition of the great arteries with microdeletion 22q11. Thirteen babies had the defect repaired (median 18 h, range 4-72 h) and 12 survived. Mechanical ventilation was required for a median of 12 days. One survivor has cerebral palsy. CONCLUSION: Of 31 prenatally diagnosed CDH cases 38% are alive, of 20 ongoing pregnancies 60% are alive, and of 13 babies who underwent surgery 92% are alive. No baby with associated malformations survived. These numbers need to be known by each member of the counselling team in order to give parents adequate information to make their decision. 相似文献
998.
Roda L Pasche J Fournier A Terorotua V Wickramasinghe SN Tamary H Schischmanoff PO Tchernia G Delaunay J 《Journal of pediatric hematology/oncology》2002,24(6):503-506
The authors attempted to assess the utility of interferon alpha2b treatment in a Polynesian girl with a relatively severe form of congenital dyserythropoietic anemia, type 1. The diagnosis was established using routine hematologic and biochemical tests, light and electron microscopy, and electrophoresis of red cell membrane proteins. Response to the treatment was monitored using the blood count and reticulocyte count. The patient was age 14 when interferon treatment was started. Previously, she had been partially dependent on transfusions, and gallstones and iron overload had developed. The dose of interferon alpha2b was initially 3 x 10 units three times a week for 1 year and 3 x 10 units twice a week thereafter. On this treatment, hemoglobin and reticulocytes increased and transfusions became unnecessary. In keeping with a few previous reports, interferon alpha2b proved to be effective in congenital dyserythropoietic anemia, type 1. The patient became transfusion-independent. More cases need to be studied to optimize the dosage of interferon alpha2b and determine how long the treatment can be tolerated. 相似文献
999.
Ranchin B Villard F André JL Canterino I Said MH Boisson RC Lachaux A David L Cochat P 《Pediatric transplantation》2002,6(4):308-312
Transient, isolated hyperphosphatasemia is a rare, benign condition of childhood. Few cases have been described in transplant patients. We report six cases: three after liver transplantation and three after kidney transplantation. Such a phenomenon was found to be as benign after organ transplantation as it is in healthy children. Hence, an isolated increase in the serum alkaline phosphatase level following transplantation should not be of concern in this population of patients. 相似文献
1000.
Protection against acute lung injury by intravenous or intratracheal pretreatment with EPI-HNE-4, a new potent neutrophil elastase inhibitor 总被引:3,自引:0,他引:3
Delacourt C Hérigault S Delclaux C Poncin A Levame M Harf A Saudubray F Lafuma C 《American journal of respiratory cell and molecular biology》2002,26(3):290-297
Excessive accumulation of active neutrophil elastase (NE) in pulmonary fluids and tissues of patients with cystic fibrosis (CF) is thought to act on the lungs, compromising their structure and function. The aim of this study was to investigate the in vitro and in vivo protective effect of a new, rapidly acting, potent (Ki = 5.45 x 10(-12) M and Kon = 8 x 10(6) M(-1) s(-1)) and specific human NE inhibitor, EPI-HNE-4, engineered from the Kunitz domain. The results demonstrated that this inhibitor was able to (i) effectively inhibit in vitro the high levels of active NE present in a medium as complex as sputum from children with CF, with a measured IC(50) equal or close to the calculated IC(50) in 60% of cases, and (ii) almost completely block (91%) the N-formyl-methionine-leucine-phenylalanine-induced migration of purified human neutrophils across a Matrigel basement membrane. Intratracheal administration (250, 175, or 100 microg per rat) of the inhibitor 5 min before instillation of pure human NE (HNE) (150 microg per rat) to rats induced effective, dose-dependent protection of the lungs, 4 h later, from hemorrhage, serum albumin leakage, residual active NE, and discrete neutrophil influx in air spaces induced by instillation of pure HNE. Intravenous administration (3 mg per rat) of EPI-HNE-4, 15 min before instillation of the soluble fraction of pooled sputum (delivering 120 microg of active NE per rat) from children with CF, effectively reduced (64%), 4 h later, the massive neutrophil influx induced by sputum instillation. Overall, these data strongly suggest that associated aerosol and systemic administration of EPI-HNE-4 would be beneficial in the treatment of CF. 相似文献