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51.

Background

Uterine fibroids are common, often symptomatic and a third of women need repeated time off work. Consequently 25% to 50% of women with fibroids receive surgical treatment, namely myomectomy or hysterectomy. Hysterectomy is the definitive treatment as fibroids are hormone dependent and frequently recurrent. Medical treatment aims to control symptoms in order to replace or delay surgery. This may improve the outcome of surgery and prevent recurrence.

Purpose

To determine whether any medical treatment can be recommended in the treatment of women with fibroids about to undergo surgery and in those for whom surgery is not planned based on currently available evidence.

Study Selection

Two authors independently identified randomised controlled trials (RCT) of all pharmacological treatments aimed at the treatment of fibroids from a list of references obtained by formal search of MEDLINE, EMBASE, Cochrane library, Science Citation Index, and ClinicalTrials.gov until December 2013.

Data Extraction

Two authors independently extracted data from identified studies.

Data Synthesis

A Bayesian network meta-analysis was performed following the National Institute for Health and Care Excellence—Decision Support Unit guidelines. Odds ratios, rate ratios, or mean differences with 95% credible intervals (CrI) were calculated.

Results and Limitations

A total of 75 RCT met the inclusion criteria, 47 of which were included in the network meta-analysis. The overall quality of evidence was very low. The network meta-analysis showed differing results for different outcomes.

Conclusions

There is currently insufficient evidence to recommend any medical treatment in the management of fibroids. Certain treatments have future promise however further, well designed RCTs are needed.  相似文献   
52.
Gabor G. Kovacs 《朊病毒》2016,10(5):369-376
Recent studies on iatrogenic Creutzfeldt-Jakob disease (CJD) raised concerns that one of the hallmark lesions of Alzheimer disease (AD), amyloid-β (Aβ), may be transmitted from human-to-human. The neuropathology of AD-related lesions is complex. Therefore, many aspects need to be considered in deciding on this issue. Observations of recent studies can be summarized as follows: 1) The frequency of iatrogenic CJD cases with parencyhmal and vascular Aβ deposits is statistically higher than expected; 2) The morphology and distribution of Aβ deposition may show distinct features; 3) The pituitary and the dura mater themselves may serve as potential sources of Aβ seeds; 4) Cadaveric dura mater from 2 examined cases shows Aβ deposition; and 5) There is a lack of evidence that the clinical phenotype of AD appears following the application of cadaveric pituitary hormone or dura mater transplantation. These studies support the notion that neurodegenerative diseases have common features regarding propagation of disease-associated proteins as seeds. However, until further evidence emerges, prions of transmissible spongiform encephalopathies are the only neurodegenerative disease-related proteins proven to propagate clinicopathological phenotypes.  相似文献   
53.
The significance of multiple mating in the social wasp Vespula maculifrons   总被引:1,自引:0,他引:1  
The evolution of the complex societies displayed by social insects depended partly on high relatedness among interacting group members. Therefore, behaviors that depress group relatedness, such as multiple mating by reproductive females (polyandry), are unexpected in social insects. Nevertheless, the queens of several social insect species mate multiply, suggesting that polyandry provides some benefits that counteract the costs. However, few studies have obtained evidence for links between rates of polyandry and fitness in naturally occurring social insect populations. We investigated if polyandry was beneficial in the social wasp Vespula maculifrons. We used genetic markers to estimate queen mate number in V. maculifrons colonies and assessed colony fitness by counting the number of cells that colonies produced. Our results indicated that queen mate number was directly, strongly, and significantly correlated with the number of queen cells produced by colonies. Because V. maculifrons queens are necessarily reared in queen cells, our results demonstrate that high levels of polyandry are associated with colonies capable of producing many new queens. These data are consistent with the explanation that polyandry is adaptive in V. maculifrons because it provides a fitness advantage to queens. Our research may provide a rare example of an association between polyandry and fitness in a natural social insect population and help explain why queens in this taxon mate multiply.  相似文献   
54.
Huttunen HJ  Greco C  Kovacs DM 《FEBS letters》2007,581(8):1688-1692
Previous studies have shown that acyl-coenzyme A:cholesterol acyl transferase (ACAT), an enzyme that controls cellular equilibrium between free cholesterol and cholesteryl esters, modulates proteolytic processing of APP in cell-based and animal models of Alzheimer's disease. Here we report that ACAT-1 RNAi reduced cellular ACAT-1 protein by approximately 50% and cholesteryl ester levels by 22% while causing a slight increase in the free cholesterol content of ER membranes. This correlated with reduced proteolytic processing of APP and 40% decrease in Abeta secretion. These data show that even a modest decrease in ACAT activity can have robust suppressive effects on Abeta generation.  相似文献   
55.
56.
Sclerotinia sclerotiorum is a pathogenic fungus that infects hundreds of plant species, including many of the world's most important crops. Key features of S. sclerotiorum include its extraordinary host range, preference for dicotyledonous plants, relatively slow evolution, and production of protein effectors that are active in multiple host species. Plant resistance to this pathogen is highly complex, typically involving numerous polymorphisms with infinitesimally small effects, which makes resistance breeding a major challenge. Due to its economic significance, S. sclerotiorum has been subjected to a large amount of molecular and evolutionary research. In this updated pathogen profile, we review the evolutionary and molecular features of S. sclerotiorum and discuss avenues for future research into this important species.  相似文献   
57.
The western massasauga (Sistrurus tergeminus) is a small pit viper with an extensive geographic range, yet observations of this species are relatively rare. They persist in patchy and isolated populations, threatened by habitat destruction and fragmentation, mortality from vehicle collisions, and deliberate extermination. Changing climates may pose an additional stressor on the survival of isolated populations. Here, we evaluate historic, modern, and future geographic projections of suitable climate for S. tergeminus to outline shifts in their potential geographic distribution and inform current and future management. We used maximum entropy modeling to build multiple models of the potential geographic distribution of S. tergeminus. We evaluated the influence of five key decisions made during the modeling process on the resulting geographic projections of the potential distribution, allowing us to identify areas of model robustness and uncertainty. We evaluated models with the area under the receiver operating curve and true skill statistic. We retained 16 models to project both in the past and future multiple general circulation models. At the last glacial maximum, the potential geographic distribution associated with S. tergeminus occurrences had a stronghold in the southern part of its current range and extended further south into Mexico, but by the mid‐Holocene, its modeled potential distribution was similar to its present‐day potential distribution. Under future model projections, the potential distribution of S. tergeminus moves north, with the strongest northward trends predicted under a climate scenario increase of 8.5 W/m2. Some southern populations of S. tergeminus have likely already been extirpated and will continue to be threatened by shifting availability of suitable climate, as they are already under threat from desertification of grasslands. Land use and habitat loss at the northern edge of the species range are likely to make it challenging for this species to track suitable climates northward over time.  相似文献   
58.
The challenging nature of studies of membrane proteins has made it difficult to determine the molecular mechanism of transmembrane signaling. For the bacterial chemoreceptor family, there are crystal structures of the internal and external domains, structural models of the transmembrane domain, and evidence for subtle ligand-induced conformational changes, but the signaling mechanism remains controversial. We have used a novel site-directed solid-state NMR distance measurement approach, using (13)C(19)F REDOR, to measure a ligand-induced change of 1.0 +/- 0.3 A in the distance between helices alpha 1 and alpha 4 of the ligand-binding domain in the intact, membrane-bound serine receptor. This distance change is shown not to be due to motion of the side chain and thus is due to motion of either the alpha 1 or the alpha 4 helix. Additional distance measurements can be used to determine the type of backbone motion and to follow it to the cytoplasm, to test and refine current proposals for the mechanism of transmembrane signaling. This is a promising general method for high-resolution measurements of local structure in intact, membrane-bound proteins.  相似文献   
59.
OBJECTIVE: To describe the cytologic features of secretory meningioma on crush preparations. STUDY DESIGN: In five cases, the diagnosis of secretory meningioma was made and crush preparations were available. In each case, crush preparations were made at the time of intraoperative consultation from an open biopsy specimen or stereotactic biopsy. RESULTS: Hematoxylin and eosin-stained crushes showed the presence of clusters of cohesive cells containing variable numbers of inclusions among less cohesive typical meningothelial cells. In two cases, the inclusions were especially prominent. Inclusions varied in size from 3 to 40 microns, had a well-defined rim and contained finely granular or hyaline material and a central core. CONCLUSION: Secretory meningiomas demonstrate distinct cytologic features on crush preparations. Recognition of these inclusions is important since their prominence in some stereotactic smear preparations may lead to diagnostic problems.  相似文献   
60.
Resistance to activated protein C determined by factor V Leiden (FVL) is the most frequent inherited risk factor of venous thrombosis. The purpose of our work was to reveal the frequency of FVL in Slovak patients with venous thromboses, to characterise the nature of venous thromboses in this inherited thrombophilia, and to consider the screening approach to investigation of FVL in patients with venous thromboses. 350 patients with a diagnosis of venous thromboembolic disease from various regions of Slovakia were investigated. FVL, detected by polymerase chain reaction, was found in 128/350 (37%) patients with venous thromboses. 118/128 (92%) patients were heterozygous and 10/128 (8%) were homozygous carriers. In 108/128 (84%) patients with FVL the thromboembolic disease occurred spontaneously. Phlebothrombosis occurred predominantly in the lower limbs--117/128 (91%) patients, atypical localisations were rare. The first thromboembolic event was manifested before 40 years of age in 69% of patients. The family history was positive in 60/128 (47%) FVL carriers with thromboembolic disease. Recurrent thrombosis occurred in 30% of patients with FVL. In agreement with findings in other European countries, the prevalence of FVL was high in Slovak patients with thromboembolic disease. The investigation of FVL seems to be justified in patients before 40 years of age with venous thrombosis of lower limbs, in the absence of triggering factors and with a family history of venous thromboembolic disease.  相似文献   
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