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81.
82.
We investigated the number of views necessary to evaluate trauma patients for suspected cervical spine fractures, comparing general and musculoskeletal radiologists. At separate sittings, independently and blindly, two musculoskeletal (MSKR) and two general (GR) radiologists evaluated sets of cervical spine images on a 1- to 5-point confidence scale for the presence of fracture in 68 trauma patients. First they evaluated anteroposterior and lateral views, then these plus an odontoid view, and lastly these three plus bilateral oblique radiographs. Overall, MSKR were slightly more accurate than GR (77.9 % vs. 74 %, P < 0.05). With two views, GR were more accurate (75.7 % vs.72.1 %); with three and five views, MSKR were more accurate (80.1 % vs.73.5 % and 81.6 % vs. 72.8 %). Confidence scores for excluding fractures increased with number of views (1.9, 1.6, 1.4, P < 0.0001); however, confidence scores for diagnosing fractures were affected neither by specialty (MSK = 3.8, GR = 3.9) nor by number of views (3.7, 3.9, 4.0). With more views, MSKR were more accurate and confident in excluding suspected cervical spine fractures than GR.  相似文献   
83.
Journal of Clinical Immunology - NF-κB essential modulator (NEMO, IKK-γ) deficiency is a rare combined immunodeficiency caused by mutations in the IKBKG gene. Conventionally, patients are...  相似文献   
84.

Background

Partial internal biliary diversion (PIBD) is an alternative approach for the treatment of devastating pruritus in patients with progressive familial intrahepatic cholestasis (PFIC). In these patients quality of life can be improved and progression of liver disease can be delayed while waiting for liver transplantation. The aim of our study was to evaluate six patients with PFIC who have undergone PIBD in long-term follow-up.

Methods

Retrospective review of the records of six patients who underwent PIBD for PFIC between 2008 and 2010 was conducted to evaluate age, growth, clinical and laboratory studies for long-term outcome.

Results

Serum postoperative bile acid levels were reduced from a mean 340.1 μmol/L (range 851–105) preoperatively to a mean of 96.3 μmol/L at postoperative fifth year. The difference between pre- and postoperative bile acid levels was statistically significant (p = 0.018). AST decreased from 79.1 U/L (range 43–150 U/L) to 64.6 U/L (range 18–172 U/L), ALT decreased from 102.8 U/L (range 35-270 U/L) to 84.6 U/L and total bilirubin decreased from 2.9 μmol/L (range 0.35–6.4 μmol/L) to 1.53 μmol/L (range 0.3–2.4). Again, the decrease in total bilirubin levels was significant (p = 0.043). Pruritus was diminished from a mean of + 4 (range 4–4) preoperatively to a mean of + 2 (4–0). One patient who underwent liver transplantation owing to relapsing pruritus died from postoperative sepsis in the early postoperative period at the fifth year after PBID. Five symptom-free patients have not required liver transplantation at a mean period of 6.1 ± 0.83 years (5.1–7.0 years) follow-up.

Conclusion

PBID is an effective surgical procedure in the long-term and can delay the need for liver transplantation in children with PFIC by reducing jaundice and pruritus.  相似文献   
85.

Background

Relapse is the leading cause of treatment failure for myeloid malignancies treated with allogeneic hematopoietic stem cell transplantation. Treatment options are very limited and use of azacitidine is one of the available options.

Methods

This was a retrospective, single-institution study. Of 28 evaluated patients, 18 were males, and the median age was 60 years (range, 15–78). There were 15 patients with acute myeloid leukemia, 8 with myelodysplastic syndrome, 4 with chronic myelomonocytic leukemia, and 1 with primary myelofibrosis. Ten patients received azacitidine for overt relapse, 14 received it as a preemptive therapy, and 4 others received it as maintenance treatment after allo-hematopoietic cell transplant (HSCT). Eleven patients received a donor lymphocyte infusion (DLI).

Results

The patients received median 5 (1–9) cycles of azacitidine in preemptive and maintenance therapy and median 2.5 (1–9) cycles in patients with relapse. Thirty-nine percent of patients received DLIs. Median overall survival was 6.1 months (95% CI, 0.7–13) for relapse therapy vs 21.2 months (95% CI, 8.4-inf) for preemptive therapy. Among patients treated for relapse, 30% achieved temporary disease control and underwent the second allo-HSCT. A complete, cytogenetic remission was achieved in 50% of patients and stable minimal residual disease in 14% of patients in a group with preemptive therapy. Toxicity was considerable; neutropenia (71%), anemia (14%), thrombocytopenia (36%), and serious infections (36%) were observed in the preemptive setting.

Conclusions

These data support the notion that azacitidine is best used as a preemptive therapy against relapse for patients after allo-HSCT performed for myeloid malignancy. Applying azacitidine as therapy for ongoing relapse after allo-HSCT may lead to stable disease and allow for better performance of the second allo-HSCT.  相似文献   
86.
87.
This study was done to evaluate and to compare the efficacy of jet nebulizer and metered dose inhaler (MDI) with home-made non-valved spacer (HM NVS) to deliver aerosolized salbutamol in acute exacerbation of asthma in children. HM NVS was made by 500ml plastic mineral water bottle. It was perforated at the bottom for the insertion of MDI and proximal end was cut for placing the mouth. This prospective randomized study was conducted in the department of Pediatrics, Dhaka Medical College Hospital, during April 2007 to March 2008 with 50 known cases (2-12 years) of bronchial asthma with acute exacerbation. After randomized enrollment, each patient received three doses of salbutamol either through a jet nebulizer or through a HM NVS. Oxygen saturation (SaO2), wheeze, heart rate, respiratory rate were recorded throughout the treatment period. Data were analyzed with SPSS for Windows 10.0 at p value <0.05 was considered significant. The mean age of patients was 59.8 months in nebulizer group versus 69.4 months in MDI with HM NVS group. Baseline clinical characteristics in nebulizer group were SaO2 87.7±2.5 versus 89.0±1.8 percent, RR 59.2±7.3 vs. 63.2±4.8 per minute, HR 155.4±11.8 versus 149.0±10.8 per minute and wheeze in 22(88.0%) cases versus 21(84.0%) cases respectively (p>0.05). After therapy improvement was noted among the nebulizer group (SaO2 87.7±2.5 vs. 94.3±2.8 percent; RR 59.2±7.3 vs. 39.3±4.9 per minute; HR 155.4±11.8 vs. 151.60±17.3 per minute; wheeze 88% vs. 8%) as well as in the MDI with HM NVS group (SaO2 89.0±1.8 vs. 94.8±1.8 percent; RR 63.2±4.8 vs. 38.7±6.4 per minute; HR 149.0±10.8 vs. 144.5±13.5 per minute; wheeze 84% vs. 16%) [p<0.001; CI:95%]. However, these improvements did not differ significantly between the nebulizer group and HM NVS group (SaO2 94.3±2.8 vs. 94.8±1.8 percent, RR 39.3±4.9 vs. 38.7±6.4 per minute, HR 151.60±17.3 vs. 144.5±13.5 per minute and wheeze persisted in 2(8.0%) cases versus 4(16.0%) cases respectively) [p>0.05]. The overall response to these modalities of treatment was satisfactory in nebulizer (19/25) and HM NVS (17/25). Salbutamol delivered through both nebulizer as well as MDI with HM NVS is equally effective in the treatment of acute asthma in children.  相似文献   
88.
Directing attention to a visual item enhances its representations, making it more likely to guide behavior (Corbetta et al. 1991). Attention is thought to produce this enhancement by biasing suppressive interactions among multiple items in visual cortex in favor of the attended item (e.g., Desimone and Duncan 1995; Reynolds and Heeger 2009). We ask whether target enhancement and modulation of suppressive interactions are in fact inextricably linked or whether they can be decoupled. In particular, we ask whether simultaneously directing attention to multiple items may be one means of dissociating the influence of attention-related enhancement from the effects of inter-item suppression. When multiple items are attended, suppressive interactions in visual cortex limit the effectiveness with which attention may act on their representations, presumably because “biasing” the interactions in favor of a single item is no longer possible (Scalf and Beck 2010). In this experiment, we directly investigate whether applying attention to multiple competing stimulus items has any influence on either their evoked signal or their suppressive interactions. Both BOLD signal evoked by the items in V4 and behavioral responses to those items were significantly compromised by simultaneous presentation relative to simultaneous presentation, indicating that when the items appeared at the same time, they interacted in a mutually suppressive manner that compromised their ability to guide behavior. Attention significantly enhanced signal in V4. The attentional status of the items, however, had no influence on the suppressive effects of simultaneous presentation. To our knowledge, these data are the first to explicitly decouple the effects of top-down attention from those of inter-item suppression.  相似文献   
89.
Discrimination of neural stem cells from other progenitors in the developing mammalian brain has been hampered by the lack of specific markers. Identifying the progenitor pools and signalling pathways that guide mammalian neurogenesis are central to understanding the complex mechanisms that govern development of the nervous system. Notch signalling plays a pivotal role in the development of the mammalian nervous system by maintaining multipotent neural stem cells and regulating their fate. In order to identify putative neural stem cells in situ, we generated transgenic mice that express Green Fluorescent Protein (GFP) and report Notch signalling activity in the developing CNS. Here we show the subdivision of progenitors within the neural tube of these mice. We purify progenitors from the neural tube and show that cells with the highest levels of Notch-reporter activity have self-renewal capability and multipotency, whereas those lacking Hes5 expression do not form neurospheres in vitro. Using marker protein co-expression and cell sorting, we show that both neuroepithelial cells as well as some radial glia at all axial levels of the embryonic neural tube display active Notch signalling. However, Tbr2-positive basal progenitors of the developing telencephalon and differentiating Islet1/2- and Lim1-positive motor neurons outside the ventricular zone do not express Hes5-GFP. Quantitative analysis showed that Hes5 expression correlates better with neural stem cell potential than expression of the related gene Hes1. Thus, Notch activity through Hes5 identifies multipotent progenitors with stem cell properties and subdivides the different progenitors into defined pools.  相似文献   
90.
Basak AN 《Hemoglobin》2007,31(2):233-241
The thalassemias are a diverse group of hemoglobin (Hb) disorders characterized by a reduced synthesis of the globin chains of Hb. Today, more than 200 mutations, affecting different levels of beta-globin gene expression, by a variety of mechanisms, are known to result in a beta-thalassemia (thal) phenotype. According to recent findings, the multilayered complexity in the phenotype of beta-thal is the result not only of marked molecular heterogeneity at the beta-globin locus, but at the level of several other genes as well. The heterogeneity at the beta-globin locus, which is the most reliable and predictive factor of disease phenotype, is simplified, to a certain extent, by the fact that the mutations are ethnic-group specific. Fifty out of >200 beta-thal mutations account for 90-95% beta-thalassemias worldwide. In the broad group of Mediterranean countries, approximately 35 mutations have been reported thus far; however, allele frequencies vary among countries. beta-Thal is a major public health concern in Turkey; throughout the country the gene frequency is estimated to be 2.1%, but in certain regions, this figure increases to 10%. The estimated number of carriers is 1,300,000 and the number of homozygous beta-thal patients is around 4,000. The number of affected births is higher than expected, since the birthrate is still very high in Turkey, and the number of consanguineous marriages is above 60% in the eastern parts of the country. Unlike many other Mediterranean countries, beta-thal in Turkey is very heterogeneous at the clinical level, transfusion-dependent beta-thal major predominating. Between 1987 and 2006, more than 1,500 patients with homozyous beta-thal, unrelated and not preselected, were investigated by DNA analysis. Our results revealed that by far the most common mutation in Turkey is IVS-I-110 (G-->A), followed by IVS-I-6 (T-->C) and frameshift codon (FSC) 8 (-AA). The six most common mutations add up to approximately 70.3%, and the overall frequency of the first 12 mutations is 83.3%. The ratio of beta (0):beta (+)-thal mutations is 1:1, but the majority of beta (+)-thal cases carry the severe IVS-I-110 lesion; thus, most of these mutations give rise to beta-thal major in homozygous or compound heterozygous combinations. In addition to the 12 common mutations, several rare and four novel beta-thal mutations were reported in the framework of this project, totaling 36 mutations. Turkey's large molecular heterogeneity can be explained by its unique geographical position and rich history, an important crossroad between cultures, civilizations and continents for several centuries. This study shows that despite its great molecular heterogeneity, and with the advent of polymerase chain reaction (PCR)-based techniques and improved methods of early fetal sampling, heterozygote screening and prenatal diagnosis are feasible in Turkey.  相似文献   
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