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51.
Aim: To determine whether growth, feeding tolerance and infectious events of preterm infants is related to the proportion of intake of mother’s own raw milk (maternal milk) versus pooled pasteurized banked breast milk (donor milk). Methods: This is a prospective observational study of 55 premature infants born less than 32 weeks of gestational age admitted to the neonatal intensive care unit at the Children’s Hospital of Toulouse during two 6‐month periods from 2003 to 2005. Enrolled infants were exclusively on enteral feeds with maternal milk ± donor milk. Results: Mean gestational age was 28.6 weeks (SD 1.5) and mean birth weight 1105 grams (SD 282). During the time of exclusively breast milk feeds, weight gain (g/kg/day) was correlated to the proportion of maternal milk consumed (p = 0.0048, r = 0.4). Necrotizing enterocolitis was inversely correlated to the amount of maternal milk. The amount of maternal milk did not impact on infectious events. Conclusion: Mother’s own raw milk improves weight gain compared with donor milk in preterm infants. Lactation strategies should be sought that helps mothers to increase their milk production.  相似文献   
52.
Mechanisms of adeno-associated virus genome encapsidation   总被引:1,自引:0,他引:1  
The defective parvovirus, adeno-associated virus (AAV), is under close scrutiny as a human gene therapy vector. AAV's non-pathogenic character, reliance on helper virus co-infection for replication and wide tissue tropism, make it an appealing vector system. The virus' simplicity and ability to generate high titer vector preparations have contributed to its wide spread use in the gene therapy community. The single stranded AAV DNA genome is encased in a 20-25 nm diameter, icosahedral protein capsid. Assembly of AAV occurs in two distinct phases. First, the three capsid proteins, VP1-3, are rapidly synthesized and assembled into an empty virion in the nucleus. In the second, rate-limiting phase, single-strand genomic DNA is inserted into pre-formed capsids. Our rudimentary knowledge of these two phases comes from radioactive labeling pulse-chase experiments, cellular fractionation and immunocytological analysis of infected cells. Although the overall pattern of virus assembly and encapsidation is known, the biochemical mechanisms involved in these processes are not understood. Elucidation of the processes of capsid assembly and encapsidation may lead to improved vector production. While all of the parvoviruses share the characteristic icosahedral particle, differences in their surface topologies dictate different receptor binding and tissue tropism. Based on the analysis of the molecular structures of the parvoviruses and capsid mutagenesis studies, investigators have manipulated the capsid to change tissue tropism and to target different cell types, thus expanding the targeting potential of AAV vectors.  相似文献   
53.
BACKGROUND: The initial rate of plasma HIV-1 RNA (pVL) decline has been proposed as a marker of early efficacy of antiretroviral therapy (ART) and a possible predictor of late efficacy. We compared the rate of pVL decline in patients starting ART with nevirapine (NVP), efavirenz (EFV), or both drugs combined in addition to lamivudine (3TC) and stavudine (d4T). METHODS: Analysis of the viral decay constant (VDc) during the first 2 weeks of treatment in patients enrolled in the 2NN study who remained on allocated treatment. RESULTS: The median VDc (log10 copies per day, [interquartile range]) was similar for NVP (0.30 [0.25-0.36], EFV (0.31 [0.27-0.37]), and NVP + EFV (0.30 [0.27-0.36]). Patients with a baseline pVL >100,000 copies/mL were 8.7 (95% confidence interval [CI]: 6.2-12.3) times more likely to have a VDc >75th percentile. A high VDc was not associated with plasma drug concentration or with a decreased risk of virologic failure at week 48 after the start of therapy (hazard ratio = 0.8, 95% CI: 0.6-1.2). CONCLUSION: NVP, EFV, or NVP + EFV in combination with 3TC and d4T show similar rates of pVL decline during the first 2 weeks of treatment. The VDc with these regimens is not predictive of late virologic efficacy.  相似文献   
54.
55.
Recent studies demonstrated the crucial role of c‐Rel in directing Treg lineage commitment and its involvement in T helper 1 (Th1) cell‐mediated autoimmune inflammation. We thus wondered whether these opposite functions of c‐Rel influence the course of antiparasitic immune responses against Leishmania major, an accepted model for the impact of T‐cell subsets on disease outcome. Here we show that c‐Rel‐deficient (rel?/?) mice infected with L. major displayed dramatically exacerbated leishmaniasis and enhanced parasite burdens. In contrast to WT mice, IFN‐γ and IL‐17 production in response to L. major antigens was severely impaired in rel?/? mice. Reconstitution of Rag1?/? T‐cell deficient mice with rel?/? CD4+ T cells followed by L. major infection demonstrated that c‐Rel‐deficient T cells mount normal Th1 responses and are able to contain the infection. Similarly, Th1 differentiation of naïve CD4+ cells in vitro was normal. Notably, a selective defect in IL‐12 and IL‐23 production was observed in rel?/? DCs compared with their WT counterparts. In conclusion, our data suggest that the expression of c‐Rel in myeloid cells is essential for clearance of L. major and that this c‐Rel‐mediated effect is dominant over the lack of Tregs.  相似文献   
56.
IntroductionThe free radial forearm (FRFA) flap is universally still considered as the gold standard technique in penile reconstruction. Typically, a considerably large flap is required, often involving almost the entire circumference of the forearm. Partial necrosis may occur at the distal-most (dorsoradial) part of the flap as a result of insufficient perfusion.AimTo describe a new technique using the posterior interosseous artery (PIOA) to supercharge FRFA phalloplasty.MethodsIn a 12-month period, all patients having FRFA flap phalloplasty were enrolled. Perioperative, after complete flap dissection, an indocyanine green perfusion scan was performed. In case of insufficient perfusion at the distalmost part of the flap, a supramicrosurgical anastomosis was performed between the FRFA pedicle and the PIOA (artery only).Main Outcome MeasuresStudied outcomes included the rate of marginal necrosis, surgical time, postoperative posterior interosseous nerve damage and urethral complications (fistula, stenosis or necrosis).ResultsA total of 27 FRFA flap phalloplasties was performed. Anastomosis of the PIOA was needed in 15 cases. No marginal necrosis was observed in these cases. There were no cases of postoperative posterior interosseous nerve damage. There were no significant differences in urethral complications (fistula, stenosis or necrosis) between the 2 groups.Clinical ImplicationsIn selected cases where insufficient perfusion of the dorsoradial part of the flap is present, patients may benefit from arterial supercharging to prevent postoperative marginal necrosis.Strength & LimitationsStrengths include a single surgeon, thus lending continuity of skill and technique, a consecutive series, and 100% short-term follow-up. Limitations include single institution series and a limited number of patients.ConclusionArterial supercharging is effective in improving perfusion of large FRFA flaps used in phalloplasty when dorsoradial hypoperfusion is detected on an indocyanine green perfusion scan. It is a technically challenging addition to the standard technique because of the small size of the vessels, the close relationship between the PIOA and the posterior interosseous nerve, and the vulnerability of the newly constructed intra-flap anastomosis.De Wolf E, Claes K, Sommeling CE, et al. Free Bipedicled Radial Forearm and Posterior Interosseous Artery Perforator Flap Phalloplasty. J Sex Med 2019;16:1111–1117.  相似文献   
57.
To elucidate the molecular mechanisms of spinal fusion with different graft materials during an anterior lumbar interbody fusion, we examined the gene-expression profiles after implantation of equine bone protein extract, rhBMP-2 and autograft using microarray technology and data analysis, including hierarchical clustering, self-organizing maps (SOM), KEGG pathway and Biological process GO analyses in a porcine model. The results suggest that equine bone protein extract exhibited a more similar expression pattern with autograft than that of rhBMP-2. rhBMP-2 recruits progenitor cells, proliferation and differentiation possibly by inducing various factors including PGHS-2, IFGBP-2, VEGF and chemokines and then leads to preferable membranous ossification and bone remodeling. Conversely, equine bone protein extract results in endochondral ossification via upregulation of cartilage-related genes. Ossification by inducing direct osteoblastic differentiation and obviating the cartilaginous intermediate phases may increase spinal fusion rate.  相似文献   
58.
Our aim was to determine the frequency of 12 common respiratory viruses in patients admitted to intensive care units with respiratory symptoms, evaluate the clinical characteristics and to compare the results to routine microbiological diagnostics. Throat swabs from 122 intensive care‐patients >18 years with acute respiratory symptoms were collected upon admission and analysed with multiplex real‐time polymerase chain reaction, for 12 community respiratory viruses. Blood and respiratory tract specimens were analysed for bacteria and fungi upon clinicians' request. Clinical and paraclinical data were collected. Viruses were detected in 19 (16%) of the 122 study patients. Five virus‐positive patients (26%) had possible clinically relevant bacteria or fungi co‐detected. Patients with exacerbation in COPD were associated with a viral infection (p = 0.02). Other comorbidities, clinical and paraclinical parameters, and death were independent of a viral infection or co‐detection of bacteria/fungi. In conclusion, respiratory viruses were frequently detected in the patients. The investigated clinical and paraclinical parameters were not different in viral infections compared to other agents, thus respiratory viruses likely have similar impact on the clinical course as other agents. In 25% of the virus‐positive patients, polymicrobial aetiology was identified. Comprehensive and sensitive diagnostic methods should be emphasized to enhance respiratory diagnostics.  相似文献   
59.
BACKGROUND: Adding clomiphene citrate (CC) to FSH for controlled ovarian stimulation (COS) decreases FSH dose required for optimum stimulation. However, because of its anti-estrogenic effects, CC may be associated with lower pregnancy rates offsetting the FSH-dose reduction benefit. Previously, we reported the success of aromatase inhibition in inducing ovulation without antiestrogenic effects. METHODS: A prospective pilot study that included women with unexplained infertility undergoing COS and intrauterine insemination. Thirty-six women received the aromatase inhibitor letrozole + FSH, 18 women received CC + FSH and 56 women received FSH only. Each woman received one treatment regimen in one treatment cycle. All patients were given recombinant or highly purified FSH (50-150 IU/day) starting on day 3 to 7 until day of hCG. RESULTS: The FSH dose needed was significantly lower in letrozole + FSH and CC + FSH groups compared with FSH-only without a difference in number of follicles >1.8 cm. Pregnancy rate was 19.1% in the letrozole + FSH group, 10.5% in the CC + FSH group and 18.7% in the FSH-only group. Both pregnancy rate and endometrial thickness were significantly lower in CC + FSH group compared with the other two groups. Estradiol (E2) levels were significantly lower in the letrozole + FSH group compared with the other two groups. CONCLUSIONS: Similar to CC, aromatase inhibition with letrozole reduces FSH dose required for COS without the undesirable antiestrogenic effects sometimes seen with CC.  相似文献   
60.
Mutations in the gene encoding the isocitrate dehydrogenase 1 gene (IDH1) occur at a high frequency (up to 80%) in many different subtypes of glioma. In this study, we have screened for IDH1 mutations in a cohort of 496 gliomas. IDH1 mutations were most frequently observed in low grade gliomas with c.395G>A (p.R132H) representing >90% of all IDH1 mutations. Interestingly, non‐p.R132H mutations segregate in distinct histological and molecular subtypes of glioma. Histologically, they occur sporadically in classic oligodendrogliomas and at significantly higher frequency in other grade II and III gliomas. Genetically, non‐p.R132H mutations occur in tumors with TP53 mutation, are virtually absent in tumors with loss of heterozygosity on 1p and 19q and accumulate in distinct (gene‐expression profiling based) intrinsic molecular subtypes. The IDH1 mutation type does not affect patient survival. Our results were validated on an independent sample cohort, indicating that the IDH1 mutation spectrum may aid glioma subtype classification. Functional differences between p.R132H and non‐p.R132H mutated IDH1 may explain the segregation in distinct glioma subtypes. © 2010 Wiley‐Liss, Inc.  相似文献   
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