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71.
72.
We attempted to prove the occurrence of generalized vasospasms in cases with eclampsia/preeclampsia and HELLP syndrome and to suggest the existence of an angiospastic syndrome of pregnancy. Sixteen cases with severe preeclampsia were evaluated. Among them, three cases were complicated by eclampsia and one case with HELLP syndrome. Cranial magnetic resonance angiography (MRA) was performed in 15 cases, and celiac angiography was performed in one case. Vasospasms were observed in 12 cases (75.0%), including all cases involving eclampsia and HELLP syndrome, and cerebral infarction was observed in one case. Typical vasospasms were found by MRA in the middle and posterior cerebral arteries with peripheral ischemic changes in cases with severe preeclampsia and eclampsia. Vasospasms of the hepatic arteries were observed by celiac angiography in a case with HELLP syndrome. Vasospasms are characteristic for patients with eclampsia/preeclampsia and HELLP syndrome, and the existence of an angiospastic syndrome of pregnancy is proposed.  相似文献   
73.
Further evaluation of the pancreatic excretion test with 5,5-dimethyl-2,4-oxazolidinedione (dimethadione, DMO) was made in comparison with the pancreozymin-secretin (PS) test on 100 normal subjects, 79 patients with chronic pancreatitis, and 83 patients with nonpancreatic disease. The diagnostic sensitivity of the oralN-benzoyl-l-tyrosyl-PABA (BT-PABA) test was estimated in 42 patients with chronic pancreatitis, on whom both PS and DMO excretion tests were performed as test of reference for exocrine pancreatic function. Pancreatic DMO excretion after secretin injection was significantly diminished in chronic pancreatitis. The DMO excretion test was more sensitive than the PS test to detect chronic pancreatitis and to distinguish between mild to moderate and advanced noncalcific chronic pancreatitis. The specificity of the DMO excretion test was more than adequate to find out pancreatic disease. The 6-hr urinary PABA excretion was significantly reduced in chronic pancreatitis. The BT-PABA test, however, showed the low sensitivity in mild to moderate chronic pancreatitis.  相似文献   
74.
Hepatic venous outflow obstruction is a relatively uncommon but important and devastating complication occurring after liver transplantation. Recently, right lateral sector liver grafts have sometimes been used in living-donor liver transplantation (LDLT), but, to our knowledge, early hepatic venous outflow obstruction has never been reported in right lateral sector LDLT. A 58-year-old woman was diagnosed with liver cirrhosis and hepatocellular carcinoma and underwent right lateral sector LDLT. Postoperatively, she developed liver dysfunction. Doppler ultrasound examination revealed flat waveforms and low-flow velocity in the right hepatic vein (RHV). A computed tomography (CT) scan revealed a ventrally distorted RHV due to hypertrophy of the liver graft. Hepatic venous obstruction was suspected and a hepatic venogram was performed. The venogram revealed stenosis of the RHV due to the distortion of the vein. We performed percutaneous transfemoral balloon dilatation, but this was not effective. We then inserted an expandable metallic stent (EMS) into the RHV. After the EMS placement, the condition of the patient improved. Venogram and CT data suggested that the obstruction of the RHV developed because of distortion of the RHV to the ventral side during liver regeneration.  相似文献   
75.
76.
Behavioral and psychological problems are often observed in patients with dementia such as that associated with Alzheimer disease, and these noncognitive symptoms place an extremely heavy burden on the family and caregivers. Although it is well know that these symptoms often are triggered by infection of peripheral organs, the underlying mechanisms for these pathological conditions are still unclear. In this study, using an Alzheimer amyloid precursor protein (APP)-transgenic mouse, we analyzed behavioral changes and brain inflammatory response induced by peripheral administration of lipopolysaccharide. Application of a unique in vivo microdialysis system revealed that the increase in brain inflammatory cytokine (interleukin-6) level was significantly higher in APP-Tg than in wild-type mice after peripheral lipopolysaccharide injection, which was associated with more severe sickness behaviors. The blood–brain barrier became more permeable in APP-Tg mice during peripherally evoked inflammation, suggesting the increased vulnerability of the blood–brain barrier to inflammation in this animal model of Alzheimer's disease. These findings might provide insight into the pathogenesis of noncognitive symptoms in dementia and a basis to develop new therapeutic treatments for them.  相似文献   
77.
The cephalic neural crest produces streams of migrating cells that populate pharyngeal arches and a more rostral, premandibular domain, to give rise to an extensive ectomesenchyme in the embryonic vertebrate head. The crest cells forming the trigeminal stream are the major source of the craniofacial skeleton; however, there is no clear distinction between the mandibular arch and the premandibular domain in this ectomesenchyme. The question regarding the evolution of the gnathostome jaw is, in part, a question about the differentiation of the mandibular arch, the rostralmost component of the pharynx, and in part a question about the developmental fate of the premandibular domain. We address the developmental definition of the mandibular arch in connection with the developmental origin of the trabeculae, paired cartilaginous elements generally believed to develop in the premandibular domain, and also of enigmatic cartilaginous elements called polar cartilages. Based on comparative embryology, we propose that the mandibular arch ectomesenchyme in gnathostomes can be defined as a Dlx1-positive domain, and that the polar cartilages, which develop from the Dlx1-negative premandibular ectomesenchyme, would represent merely posterior parts of the trabeculae. We also show, in the lamprey embryo, early migration of mandibular arch mesenchyme into the premandibular domain, and propose an updated version of the heterotopy theory on the origin of the jaw.  相似文献   
78.
The nucleus prethalamicus (PTh) receives fibers from the optic tectum and then projects to the dorsal telencephalon in the yellowfin goby Acanthogobius flavimanus. However, it remained unclear whether the PTh is a visual relay nucleus, because the optic tectum receives not only visual but also other sensory modalities. Furthermore, precise telencephalic regions receiving prethalamic input remained unknown in the goby. We therefore investigated the full set of afferent and efferent connections of the PTh by direct tracer injections into the nucleus. Injections into the PTh labeled cells in the optic tectum, ventromedial thalamic nucleus, central and medial parts of the dorsal telencephalon, and caudal lobe of the cerebellum. We found that the somata of most tecto‐prethalamic neurons are present in the stratum periventriculare. Their dendrites ascend to reach the major retinorecipient layers of the tectum. The PTh is composed of two subnuclei (medial and lateral) and topographic organization was appreciated only for tectal projections to the lateral subnucleus (PTh‐l), which also receives sparse retinal projections. In contrast, the medial subnucleus receives fibers only from the medial tectum. We found that the PTh projects to nine subregions in the dorsal telencephalon and four in the ventral telencephalon. Furthermore, cerebellar injections revealed that cerebello‐prethalamic fibers cross the midline twice to innervate the PTh‐l on both sides. The present study is the first detailed report on the full set of the connections of PTh, which suggests that the PTh relays visual information from the optic tectum to the telencephalon.  相似文献   
79.
European Journal of Clinical Microbiology & Infectious Diseases - The aim of this study is to clarify the characteristics of gram-negative bacteremia (GNB), including extended-spectrum...  相似文献   
80.
Defects in the O-mannosyl glycan of α-dystroglycan (α-DG) are associated with α-dystroglycanopathy, a group of congenital muscular dystrophies. While α-DG has many O-mannosylation sites, only the specific positions can be modified with the functional O-mannosyl glycan, namely, core M3-type glycan. POMGNT2 is a glycosyltransferase which adds β1,4-linked GlcNAc to the O-mannose (Man) residue to acquire core M3-type glycan. Although it is assumed that POMGNT2 extends the specific O-Man residues around particular amino acid sequences, the details are not well understood. Here, we determined a series of crystal structures of POMGNT2 with and without the acceptor O-mannosyl peptides and identified the critical interactions between POMGNT2 and the acceptor peptide. POMGNT2 has an N-terminal catalytic domain and a C-terminal fibronectin type III (FnIII) domain and forms a dimer. The acceptor peptide is sandwiched between the two protomers. The catalytic domain of one protomer recognizes the O-mannosylation site (TPT motif), and the FnIII domain of the other protomer recognizes the C-terminal region of the peptide. Structure-based mutational studies confirmed that amino acid residues of the catalytic domain interacting with mannose or the TPT motif are essential for POMGNT2 enzymatic activity. In addition, the FnIII domain is also essential for the activity and it interacts with the peptide mainly by hydrophobic interaction. Our study provides the first atomic-resolution insights into specific acceptor recognition by the FnIII domain of POMGNT2. The catalytic mechanism of POMGNT2 is proposed based on the structure.  相似文献   
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