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991.

Background

Immunomodulatory therapy has shown some therapeutic benefits in patients with anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis. In this report, we describe the use of adrenocorticotropic hormone (ACTH) immunotherapy with good outcome in a patient with anti-NMDAR encephalitis.

Subject and Methods

A 4-year-old girl developed convulsions in her right arm and leg without impaired consciousness. These convulsions occurred frequently in clusters of 10–20 events of 10–20?s duration. She was admitted to our hospital on the 6th?day following her initial series of convulsions. Flaccid paralysis of the right hand and leg was also found. Interictal electroencephalography showed high-amplitude slow waves. No abnormal findings were shown on MRI. 99mTc-ECD brain SPECT on the 14th?day showed hyperperfusion in the left hemisphere, including the left basal ganglia. The convulsions ceased following the oral administration of valproic acid on the 10th?day; however, paralysis associated with choreic dyskinesia of the right arm and leg remained. ACTH immunotherapy was then performed on the 15th?day. We identified the presence of N-methyl-D-aspartate receptor antibody in CSF samples taken on the 6th?day. After ACTH therapy, the patient fully recovered from the paralysis associated with choreic dyskinesia of the right arm and leg. She has not had a relapse and has not required medication for over a year.

Conclusion

ACTH immunotherapy may be a useful treatment option for patients with anti-NMDAR encephalitis, although further evaluation is required.  相似文献   
992.

Background

Rett syndrome (RTT) is a neurodevelopmental disorder primarily caused by mutations in the methyl-CpG-binding protein 2 (MECP2) gene, resulting in developmental regression after normal development during infancy. Transient presentation of many autistic features is also commonly seen in RTT. Anti-myelin oligodendrocyte glycoprotein (MOG)-antibody encephalitis is an acquired relapsing demyelinating syndrome characterized by a variety of neuroinflammatory symptoms. Here, we report a case of anti-MOG antibody encephalitis in a patient with genetically confirmed RTT, which mimicked many of the features of RTT.

Case report

A three-year-old girl presented with subacute verbal and motor dysfunction, along with involuntary movements and marked irritability. Magnetic resonance imaging (MRI) revealed extensive white matter lesions, with anti-MOG antibodies detected in the serum and cerebrospinal fluid, resulting in an initial diagnosis of anti-MOG antibody encephalitis. However, additional testing of the MECP2 gene was performed in response to persistent involuntary hand movements in combination with progressive verbal and motor deterioration. Sequencing analysis revealed a known pathogenic mutation in MEPC2, indicating a concurrent diagnosis of RTT.

Conclusion

Both RTT and anti-MOG antibody encephalitis are rare conditions. Similarities in disease presentation suggest that anti-MOG antibody encephalitis may mimic many of the symptoms of RTT.  相似文献   
993.
994.
Glycerophospholipids in biological membranes are metabolically active and participate in a series of deacylation–reacylation reactions, which may lead to accumulation of polyunsaturated fatty acids (PUFAs) at the sn -2 position of the glycerol backbone. The reacylation reaction is believed to be catalyzed by acyl-coenzyme A (acyl-CoA):lysophospholipid acyltransferase. Very recently, we have shown that Caenorhabditis elegans mboa-7 , which belongs to the membrane-bound O -acyltransferase (MBOAT) family, encodes lysophosphatidylinositol (LPI)-specific acyltransferase (LPIAT). In this study, we found that knockdown of another member of the MBOAT family in C. elegans , named mboa-6 , reduced incorporation of exogenous PUFAs into phosphatidylcholine (PC), phosphatidylserine (PS) and phosphatidylethanolamine (PE) in C. elegans . Knockdown of a human mboa-6 homologue, referred to as MBOAT5, also impaired the incorporation of PUFAs into PC, PS and PE in HeLa cells. In in vitro assays, lysoPC (LPC), lysoPS (LPS) and lysoPE (LPE) acyltransferase activities using [14C]arachidonoyl-CoA were significantly reduced in the microsomes of MBOAT5 knockdown cells. Conversely, over-expression of MBOAT5 in human embryonic kidney (HEK) 293 cells resulted in great increases in LPC, LPS and LPE acyltransferase activities but not in LPIAT or lysophosphatidic acid (LPA) acyltransferase (LPAAT) activities. These results indicate that human MBOAT5 is a lysophospholipid acyltransferase acting preferentially on LPC, LPS and LPE.  相似文献   
995.
Two murine monoclonal antibodies, SK-930 (isotype IgG2a) and SK-117 (isotype IgG1), were produced from spleen cells of mice immunized against human pancreatic carcinoma cell lines, MIA-PaCa 2 and Panc-1. With the use of the avidin-biotin-immunoperoxidase technique, the SK-930 and SK-117 antibodies detected an antigen found in 24 and 23 formalin-fixed tissue sections, respectively, of tumors obtained from 30 different patients with pancreatic carcinoma. Reactivity was also frequently found with tumors of the gallbladder, bile duct, stomach, colon and esophagus, while a large panel of normal human tissues, including normal pancreatic tissues, displayed little reactivity. These observations suggest that SK-930 and SK-117 are of value in identifying tumor-associated antigen (TAA) expressed in pancreatic carcinoma and other carcinomas of the digestive system. SK-930 antibody immunoprecipitated a 134 kilodalton molecule from extracts of 125I- or [35S]methionine- or [3H]glucosamine-labeled tumor cells. The SK-117-defined antigen corresponds to 152/137 kilodalton molecules. Moreover, cytofluorometric analyses showed that cells treated with periodic acid exhibited greatly decreased reactivity to the two antibodies, but cells treated with neuraminidase, trypsin or pronase showed unchanged reactivity. The findings suggest that the epitopes of the novel TAA expressed on pancreatic carcinoma cells are carbohydrate moieties.  相似文献   
996.
997.
Urine samples from two patients with the Lowe syndrome were analyzed for sialic acid and mucopolysaccharides. The sialic acid content, relative to the creatinine content, was 4--5 times higher in these patients' urine than in normal urine. Most of the sialic acid was found in unidentified glycoproteins of high molecular weight, but the levels of sialyllactose and free sialic acid were also elevated about 2 fold. A most remarkable finding was the excretion of undersulfated chrondroitin sulfate A without other mucopolysaccharides normally occurring in urine. It is suggested that a disorder in sulfation of mucopolysaccharides is etiologically implicated in the Lowe syndrome.  相似文献   
998.
With the experimental design of this study the following conclusions were reached. 1. Biting force during maximum clenching was the greatest when the occlusal plane was made parallel to the ala-tragus line. It decreased when the occlusal plane was inclined about 5 degrees anteriorly or about 5 degrees posteriorly. 2. The efficiency of biting force exertion during maximum clenching showed the best value when the occlusal plane was made parallel to the ala-tragus line. 3. Muscle activity during clenching at various given forces was least when the occlusal plane was made parallel to the ala-tragus line. The anteroposterior inclination of the occlusal plane tends to affect the biting force, and the method with the ala-tragus line seems to be the most reasonable for occlusal plane orientation.  相似文献   
999.
1000.
There exists a microdomain called "raft" in the cell membrane. The enrichment of cholesterol and sphingolipids in its outer leaflet is well recognized. In contrast, little is known of the lipid composition of the inner leaflet of raft, where many acylated signal-transducing molecules, such as trimeric G proteins and protein tyrosine kinases, associate. NAP-22 is a neuronal protein localized on the inner leaflet of raft domain. This protein was found to bind cholesterol in the liposome. In this study, we further analyze the lipid binding activity of NAP-22 using eukaryotic and bacterial expression systems. In addition to cholesterol, NAP-22 showed a phosphatidylethanolamine (PE)- and polyphosphoinositide-dependent membrane binding in the liposome assay. The N-terminal myristoylation was essential for the liposome binding. The C-terminal deletion up to D61 showed little effect on the binding. The lipid binding region was hence judged to be in the N-terminal 60-amino-acid sequence. NAP-22 was then expressed in COS7 cells, and the intracellular localization was studied. Biochemical analysis showed the localization of NAP-22 in a Triton-insoluble low-density fraction. Cell staining analysis showed colocalization patterns of NAP-22 with PE and cholesterol in the membrane.  相似文献   
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