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941.
We present the interesting case of a 38-year-old man with a primary malignant tumor of the right testis that metachronously metastasized to the urinary bladder and the stomach. Histologically, the testicular tumor was a mixed germ cell tumor composed of teratoma and embryonal carcinoma, but it also contained a sarcoma component of somatic type malignancy. Metastases showed rhabdomyoblastic differentiation histologically identical to the sarcoma component of the testicular tumor that was diagnosed as rhabdomyosarcoma. By applying fluorescence in situ hybridization (FISH) to the cytogenetic examination of cells taken from the periventricular lymph node metastases, we demonstrated a structural chromosomal aberration characteristic of testicular neoplasms, i.e. the presence of isochromosome 12p (i(12p)). Additionally, the diagnosis was supported by immunohistochemistry.  相似文献   
942.
Chondrosarcoma is the second most frequent bone sarcoma. Due to the inherent chemotherapy and radiotherapy resistance and absence of known therapeutic targets, clinical management is limited to surgical resection. Consequently, patients with advanced disease face a poor prognosis. Hence, elucidating regulatory networks governing chondrosarcoma pathogenesis is vital for development of effective therapeutic strategies. Here, miRNA and mRNA next generation sequencing of different subtypes of human chondrogenic tumors in combination with in silico bioinformatics tools were performed with the aim to identify key molecular factors. We identified miR-143/145 cluster levels to inversely correlate with tumor grade. This deregulation was echoed in the miRNA plasma levels of patients and we provided the first evidence that circulating miR-145 is a potential noninvasive diagnostic biomarker and can be valuable as an indicator to improve the currently challenging diagnosis of cartilaginous bone tumors. Additionally, artificial upregulation of both miRNAs impelled a potent tumor suppressor effect in vitro and in vivo in an orthotopic xenograft mouse model. A combined in silico/sequencing approach revealed FSCN1 as a direct target of miR-143/145, and its depletion phenotypically resembled miR-143/145 upregulation in vitro. Last, FSCN1 is a malignancy-promoting factor associated with aggressive chondrosarcoma progression. Our findings underscore miR-143/145/FSCN1 as important players in chondrosarcoma and may potentially open new avenues for specific therapeutic intervention options. © 2020 American Society for Bone and Mineral Research.  相似文献   
943.
Many articles have reported that adrenal chromaffin cell transplants produce analgesic effects. Surprisingly, studies conducted in our laboratory failed to detect analgesic effects of adrenal chromaffin cell transplants. Although we have attempted to replicate the procedures reported to produce analgesic effects with adrenal chromaffin transplants, many of the different cell preparation procedures we have examined are fairly complex, and it is possible that our transplants were not sufficiently viable because of some subtle difference in our cell preparation procedures. In the present study we attempted to replicate as precisely as possible, and with very large groups to maximize statistical power, the simplest and most straightforward procedures previously reported to produce analgesic effects, adrenal allografts in the formalin test. The first experiment, conducted in our laboratories, failed to detect analgesic effects of intrathecal adrenal allografts in the formalin test. Another study conducted at a different research facility confirmed the absence of analgesic effects in the formalin test but verified that analgesic effects of morphine were detectable under the same blinded conditions. In addition, graft viability was verified histologically, but there was no correlation in either experiment between adrenal chromaffin cell number and pain behaviors. These results demonstrate more clearly than any of our previous reports that the analgesic effects of intrathecal adrenal transplants are not reliable and should not be accepted as valid until they can be produced reliably under rigorously blinded conditions.  相似文献   
944.
The Aleutian mink disease virus (AMDV) is one of the most serious threats to modern mink breeding. The disease can have various courses, from progressive to subclinical infections. The objective of the study was to provide a comparative molecular characterization of isolates of AMDV from farms with a clinical and subclinical course of the disease. The qPCR analysis showed a difference of two orders of magnitude between the number of copies of the viral DNA on the farm with the clinical course of the disease (105) and the farm with the subclinical course (103). The sequencing results confirm a high level of homogeneity within each farm and variation between them. The phylogenetic analysis indicates that the variants belonging to different farms are closely related and occupy different branches of the same clade. The in silico analysis of the effect of differences in the sequence encoding the VP2 protein between the farms revealed no effect of the polymorphism on its functionality. The close phylogenetic relationship between the isolates from the two farms, the synonymous nature of most of the polymorphisms and the potentially minor effect on the functionality of the protein indicate that the differences in the clinical picture may be due not only to polymorphisms in the nucleotide and amino acid sequences, but also to the stage of infection on the farm and the degree of stabilization of the pathogen–host relationship.  相似文献   
945.
Objective To evaluate the precipitating factors for heart failure decompensation in primary care and associations with short-term prognosis. Design Prospective cohort study with a 30-d follow-up from an index consultation. Regression models to determine independent factors associated with hospitalisation or death.Setting Primary care in ten European countries. Patients Patients with diagnosis of heart failure attended in primary care for a heart failure decompensation (increase of dyspnoea, unexplained weight gain or peripheral oedema).Main outcome measures Potential precipitating factors for decompensation of heart failure and their association with the event of hospitalisation or mortality 30 d after a decompensation.Results Of 692 patients 54% were women, mean age 81 (standard deviation [SD] 8.9) years; mean left ventricular ejection fraction (LVEF) 55% (SD 12%). Most frequently identified heart failure precipitation factors were respiratory infections in 194 patients (28%), non-compliance of dietary recommendations in 184 (27%) and non-compliance with pharmacological treatment in 157 (23%). The two strongest precipitating factors to predict 30 d hospitalisation or death were respiratory infections (odds ratio [OR] 2.8, 95% confidence interval [CI] (2.4–3.4)) and atrial fibrillation (AF) > 110 beats/min (OR 2.2, CI 1.5–3.2). Multivariate analysis confirmed the association between the following variables and hospitalisation/death: In relation to precipitating factors: respiratory infection (OR 1.19, 95% CI 1.14–1.25) and AF with heart rate > 110 beats/min (OR 1.22, 95% CI 1.10–1.35); and regarding patient characteristics: New York Heart Association (NYHA) III or IV (OR 1.22, 95% CI 1.15–1.29); previous hospitalisation (OR 1.15, 95% CI 1.11–1.19); and LVEF < 40% (OR 1.14, 95% CI 1.09–1.19).Conclusions In primary care, respiratory infections and rapid AF are the most important precipitating factors for hospitalisation and death within 30 d following an episode of heart failure decompensation.

Key points

  • Hospitalisation due to heart failure decompensation represents the highest share of healthcare costs for this disease.
  • So far, no primary care studies have analysed the relationship between precipitating factors and short term prognosis of heart failure decompensation episodes.
  • We found that in 692 patients with heart failure decompensation in primary care, the respiratory infection and rapid atrial fibrillation (AF) increased the risk of short-term hospital admission or death.
  • Patients with a hospital admission the previous year and a decompensation episode caused by respiratory infection were even more likely to be hospitalized or die within 30 d.
  相似文献   
946.
Introduction: The mechanism of the cytotoxicity of anthracyclines is pleiotropic and its significance in cell growth inhibition seems to be highly specific and dependent on cell type and anthracycline drug. Resistance and the high cardiotoxicity of anthracyclines have stimulated many studies aimed at identifying critical substituents required for optimal activity. Many authors point to the fact that the double-strand breaks, the consequence of the activity of topoisomerase II poisons, and the inability of cells to repair the DNA lesions are the signal for apoptosis. The aim of this study was to define the influence of 4-demetoxy 2’-halogenated analogs with altered basicity at the 3’-position on topoisomerase II and the relationship of that interaction with apoptosis and the cytotoxicity of these novel anthracyclines. Parental human ME18 melanoma cells and the ME18/R subline, obtained experimentally, resistant to doxorubicin (DOX), exposed to 1.7 and 8.6 μM DOX or its analogs, annamycin and WP903 (both 0.3 and 3.0 μM) were studied. Materials and Methods: The MTT test was used to assay cytotoxicity. Interaction of the drugs with topoisomerase II and apoptosis were done by Western blot and fluorescence microscopy using Hoechst 33342. Results: The structural changes at positions 4, 2’, and 3’ can influence topoisomerase II interaction and apoptotic activity, although correlation between these events and cytotoxic consequences has not been proved. Conclusions: The biological response of the cells to the structurally similar anthracyclines may be variable and probably depends on the cell type which seems to be an additional problem in the multifactorial resistance of tumor cells to anthracyclines.  相似文献   
947.
Complex chromosome rearrangements (CCRs) are rare structural abnormalities that involve at least two chromosomes and more than two breakpoints and are often associated with developmental delay, mental retardation, and congenital anomalies. We report on a de novo, apparently balanced translocation t(1;5;7)(p32.1;q14.3;p21.3) involving three chromosomes in a 7-year-old boy with severe psychomotor retardation, neonatal muscular hypertonia, congenital heart defect, polysyndactyly of hands and feet, and dysmorphic features resembling Greig cephalopolysyndactyly syndrome. Analysis of the chromosome breakpoints using fluorescence in situ hybridization (FISH) with locus-specific BAC clones and long-range PCR products did not identify chromosome imbalance at any of the interrogated regions. High-resolution comparative genomic hybridization (HR-CGH) and array CGH (aCGH) revealed two additional cryptic de novo deletions, del(1)(p31.1p31.1) and del(7)(p14.1p14.1), respectively, that are not associated with the translocation breakpoints. FISH and polymorphic marker analyses showed that the deletion on derivative chromosome 1 is between 4.2 and 6.1 Mb, and the deletion on derivative chromosome 7 is approximately 5.1 Mb, and that both are paternal in origin. The deletion on chromosome 7p encompasses the GLI3 gene that is causative for the Greig cephalopolysyndactyly, Pallister-Hall and some cases of Acrocallosal syndromes. We discuss the potential mechanisms of formation of the described CCR.  相似文献   
948.
This study describes the topography, borders and divisions of the globus pallidus in the Brazilian short-tailed opossum (Monodelphis domestica) and distribution of the three calcium binding proteins, parvalbumin (PV), calbindin D-28k (CB) and calretinin (CR) in that nucleus. The globus pallidus of the opossum consists of medial and lateral parts that are visible with Nissl or Timm's staining and also in PV and CR immunostained sections. Neurons of the globus pallidus expressing these proteins were classified into three types on the basis of size and shape of their soma and dendritic tree. Type 1 neurons had medium-sized fusiform soma with dendrites sprouting from the opposite poles. Neurons of the type 2 had medium-to-large, multipolar soma with scarce, thin dendrites. Cell bodies of type 3 neurons were small and either ovoid or round. Immunostaining showed that the most numerous were neurons expressing PV that belonged to all three types. Density of the PV-immunopositive fibers and puncta correlated with the density of the PV-labeled neurons. Labeling for CB resulted mainly in the light staining of neuropil in both parts of the nucleus, while the CB-expressing cells (mainly of the type 2) were scarce and placed only along the border of the globus pallidus and putamen. Staining for calretinin resulted in labeling almost exclusively the immunoreactive puncta and fibers that were distributed with medium-to-high density throughout the nucleus. Close to the border of globus pallidus with the putamen these fibers (probably dendrites) were long, thin and varicous, while more medially bundles of thick, short and smooth fibers predominated. Single CR-ir neurons (all of the type 3) were scattered through the globus pallidus. Colocalization of two calcium binding proteins in one neuron was. never observed. The CB-ir puncta (probably terminals of axons projecting to the nucleus) frequently formed basket-like structures around the PV-ir neurons. Therefore, the globus pallidus in the opossum, much as that in the rat, consists of a heterogeneous population of neurons, probably playing diversified functions.  相似文献   
949.
OBJECTIVE: To identify the views of health professionals, patients and their carers on strategies to improve the use and management of warfarin in older patients with atrial fibrillation. DESIGN: Qualitative study based on analysis of group interviews. SETTING: A major metropolitan teaching hospital, from 1 March to 30 April 2003. PARTICIPANTS: 14 patients (>/= 65 years) with established atrial fibrillation and taking warfarin, three carers, 12 specialists, eight general practitioners, six community pharmacists, nine hospital pharmacists, and 11 nurses volunteered in response to flyers promoting the study. RESULTS: Suggested strategies to improve warfarin management targeted support services for GPs and patients. Hospital-based clinicians felt that dissemination of trial evidence to GPs to support treatment recommendations is required, and that GPs need to enlist allied health professionals in the management of patients taking warfarin. GPs preferred access to practical advice from expert colleagues on the day-to-day management. Patients requested more information about warfarin therapy, as access to information is inadequate, particularly from primary sources (GPs, community pharmacists). Verbal and written information are equally important, but a single counselling session or supply of a booklet was viewed as inadequate. Participants identified various interventions for all levels of warfarin management; from the collective input, a framework for management strategies was developed. CONCLUSIONS: Health professionals and patients require more customised information to support warfarin use and management.  相似文献   
950.
Developing caring competences is considered to be one of the most important aims of undergraduate nursing education and the role of clinical placement is recognised as special in this regard. Students' reflection on caring, their experience and obstacles in being caring is recommended as a key strategy in the process of teaching and studying the nursing discipline. Therefore, the aim of this study was to describe the concept of caring, its manifestations and possible obstacles while caring, as perceived by first‐year nursing students before and after their first clinical placement. Qualitative content analysis of 15 Polish students' narratives written before and after their clinical experience in the form of text‐diaries was undertaken. The findings revealed that students entered their nursing education with a deep humanistic vision of caring both on theoretical and practical levels and the first clinical placement has enriched this vision. Expressive caring was more appreciated by students than the instrumental one and their concept of caring was coherent with the caring behaviours as described in their narratives. Several internal and external obstacles for caring have been reported by students, indicating a specific tension between their ideal of caring and their practical experience of caring in the clinical reality.  相似文献   
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