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31.
Ozono K  Kubota T 《Clinical calcium》2003,13(12):1523-1529
Osteoporosis is the most common metabolic bone disease and caused by multiple nutritional, environmental and genetical factors. Bone mineral density (BMD) is rather strongly under genetical control. A number of candidate genes have been studied with respect to the impact on BMD. Also, gene loci of susceptibility genes for osteoporosis have been identified by family-based association and linkage approaches. In particular, LRP5 is an important molecule involved in the determination of BMD, because its abnormality is associated with osteoporosis-pseudoglioma syndrome or autosomal dominant syndrome characterized by high bone density. These findings may contribute to new strategy to teat patients with osteoporosis.  相似文献   
32.
Purkinje fibers play essential roles in impulse propagation to the ventricles, and their functional impairment can become arrhythmogenic. However, little is known about precise spatiotemporal pattern(s) of interconnection between Purkinje-fiber network and the underlying ventricular myocardium within the heart. To address this issue, we simultaneously visualized intracellular Ca(2+) dynamics at Purkinje fibers and subjacent ventricular myocytes in Langendorff-perfused rat hearts using multi-pinhole type, rapid-scanning confocal microscopy. Under recording of electrocardiogram at room temperature spatiotemporal changes in fluo3-fluorescence intensity were visualized on the subendocardial region of the right-ventricular septum. Staining of the heart with either fluo3, acetylthiocholine iodide (ATCHI), or di-4-ANEPPS revealed characteristic structures of Purkinje fibers. During sinus rhythm (about 60 bpm) or atrial pacing (up to 3 Hz) each Purkinje-fiber exhibited spatiotemporally synchronous Ca(2+) transients nearly simultaneously to ventricular excitation. Ca(2+) transients in individual fibers were still synchronized within the Purkinje-fiber network not only under high-K(+) (8 mM) perfusion-induced Purkinje-to-ventricular (P-V) conduction delay, but also under unidirectional, orthodromic P-V block produced by 10-mM K(+) perfusion. While spontaneous, asynchronous intracellular Ca(2+) waves were identified in injured fibers of Purkinje network locally, surrounding fibers still exhibited Ca(2+) transients synchronously to ventricular excitation. In summary, these results are the first demonstration of intracellular Ca(2+) dynamics in the Purkinje-fiber network in situ. The synchronous Ca(2+) transients, preserved even under P-V conduction disturbances or under emergence of Ca(2+) waves, imply a syncytial role of Purkinje fibers as a specialized conduction system, whereas unidirectional block at P-V junctions indicates a substrate for reentrant arrhythmias.  相似文献   
33.
Summary A case of cerebellar hemangioblastoma associated with slight but definite erythrocytosis is reported. Operative removal of the tumor resulted in the reversion to a normal blood picture. Erythropoietin-like activity, being non-dialyzable and relatively thermolabile, was detected in the fluid aspirated from tumor. The mother of the reported patient suffered from the same disease which was also associated with a slight degree of erythrocytosis.
Zusammenfassung Es wird über den Fall eines cerebellaren Hämangioblastoms begleitet von einer leichten, aber doch eindeutig diagnostizierten Erythrozytose berichtet. Die operative Entfernung des Tumors führte zu einer Renormalisierung des Blutbildes. In der aus dem Tumor aspirierten Flüssigkeit wurde eine erythropoetinähnliche Wirkung entdeckt, die relativ thermolabil und nicht dialysierbar war. Die Mutter des geschilderten Patienten litt an der gleichen Krankheit, die ebenfalls von einer Erythrozytose leichten Grades begleitet war.
  相似文献   
34.
Monocytes and kidney-resident macrophages are considered to be involved in the pathogenesis of renal ischemia-reperfusion injury (IRI). Several subsets of monocytes and macrophages are localized in the injured tissue, but the pathologic roles of these cells are not fully understood. Here, we show that CD169+ monocytes and macrophages have a critical role in preventing excessive inflammation in IRI by downregulating intercellular adhesion molecule-1 (ICAM-1) expression on vascular endothelial cells. Mice depleted of CD169+ cells showed enhanced endothelial ICAM-1 expression and developed irreversible renal damage associated with infiltration of a large number of neutrophils. The perivascular localization of CD169+ monocytes and macrophages indicated direct interaction with blood vessels, and coculture experiments showed that the direct interaction of CD169+ cell-depleted peripheral blood leukocytes augments the expression levels of ICAM-1 on endothelial cells. Notably, the transfer of Ly6Clo monocytes into CD169+ cell-depleted mice rescued the mice from lethal renal injury and normalized renal ICAM-1 expression levels, indicating that the Ly6Clo subset of CD169+ monocytes has a major role in the regulation of inflammation. Our findings highlight the previously unknown role of CD169+ monocytes and macrophages in the maintenance of vascular homeostasis and provide new approaches to the treatment of renal IRI.  相似文献   
35.
Active Absorbable Algal Calcium (AAA Ca) is made by submaximally (800 degrees ) heating cleaned oyster shell under reduced pressure and mixing it with similarly heated seaweed (Cystophyllum fusiforme). AAA Ca, the best absorbed from the intestine than other available calcium compounds, consequently most efficiently suppresses parathyroid hormone secretion, increases bone mineral density and decreases vertebral fracture. Aging is associated with calcium deficiency, mostly because of the decreased biosynthesis of 1,25 (OH)2 vitamin D in the kidney. Parathyroid hormone consequently increases, contributing to various diseases associated with aging such as osteoporosis or decrease of calcium in the bone, as well as hypertension, arteriosclerosis, Alzheimer's disease and osteoarthritis due to paradoxical increase of calcium in vascular walls, brain, cartilage and intracellular compartment of many kinds of cells. Mild calcium deficiency is hard to detect despite these serious consequences because of the remarkable constancy of blood calcium concentration maintained by elaborate homeostatic control. Only by successfully counteracting calcium deficiency by AAA Ca with outstanding absorbability, the phenomenon of calcium paradox becomes a recognizable reality within our reach.  相似文献   
36.
We report a case of selenium deficiency in a patient with Crohn's disease on long-term total parenteral nutrition (TPN). She manifested lassitude of the legs, discoloration of the nail beds, and macrocytosis. Since her plasma selenium level was found to be below the measurable level, we diagnosed this case as selenium deficiency. After intravenous administration of sodium selenite, her symptoms were reversed. Careful attention should be paid to selenium deficiency when a patient receives long-term TPN; supplementary administration of selenium via TPN may be required because selenium is often not routinely added to TPN formulations.  相似文献   
37.
Surgical resection is the only hope for cure in patients with pancreatic cancer. To improve the resectability and achieve better prognosis of this lethal disease, extended resection for pancreatic cancer has been applied. We have performed portal vein resection aggressively for pancreatic cancer with portal vein invasion. We also established a method of portal vein reconstruction using the left renal vein graft for tumors widely extended to the portal vein. Our data show similar survival between patients with portal vein obstruction and those without invasion. We also show that portal vein reconstruction using the left renal vein graft can be performed safely without severe liver damage. With video, we introduce our surgical technique for portal vein resection and reconstruction, especially focusing on the usage of the left renal vein graft, providing several tips for a safe and successful procedure.  相似文献   
38.
BackgroundThe diagnostic assessment of the level of difficulty in treating patients who need prosthodontic care is useful to establish a medico-economically efficient system with primary care dentists and prosthodontic specialists.Materials and methodsA multi-axis assessment protocol was established using the newly established treatment difficulty indices. The protocol contains Axis I: oral physiological conditions (e.g., teeth damage and/or missing teeth); Axis II: general health and sociological conditions (e.g., medical disorders); Axis III: oral health-related quality of life (OHRQOL; e.g., oral health impact profile: OHIP); and Axis IV: psychological health (e.g., mood, anxiety, somatoform disorders). A preliminary study on the test–retest consistency of the protocol was conducted to check the levels of reliability of the indices prior to a large-scale, multi-center cohort study on the validity of the protocol.ResultsThe test–retest consistency in terms of the oral physiological condition (Axis I) after data reduction was 0.63 for patients with teeth problems, 0.95 for partially edentulous patients, and 0.62 for edentulous patients. The reliability for general health and sociological conditions (Axis II), OHRQOL (Axis III), and psychological health (Axis IV) were 0.88, 0.74, and 0.61, respectively. These values reflect either “sufficient agreement” or “excellent agreement” in accordance with the criteria established by Landis and Koch (1977) [1].ConclusionThis protocol is the first multi-axis assessment scheme introduced for prosthodontic treatment with sufficient reliability. This new system is therefore expected to have a significant impact on future dental diagnostic nomenclature systems.  相似文献   
39.
40.
Fifty percent of Diamond-Blackfan anemia (DBA) patients possess mutations in genes coding for ribosomal proteins (RPs). To identify new mutations, we investigated large deletions in the RP genes RPL5, RPL11, RPL35A, RPS7, RPS10, RPS17, RPS19, RPS24, and RPS26. We developed an easy method based on quantitative-PCR in which the threshold cycle correlates to gene copy number. Using this approach, we were able to diagnose 7 of 27 Japanese patients (25.9%) possessing mutations that were not detected by sequencing. Among these large deletions, similar results were obtained with 6 of 7 patients screened with a single nucleotide polymorphism array. We found an extensive intragenic deletion in RPS19, including exons 1-3. We also found 1 proband with an RPL5 deletion, 1 patient with an RPL35A deletion, 3 with RPS17 deletions, and 1 with an RPS19 deletion. In particular, the large deletions in the RPL5 and RPS17 alleles are novel. All patients with a large deletion had a growth retardation phenotype. Our data suggest that large deletions in RP genes comprise a sizable fraction of DBA patients in Japan. In addition, our novel approach may become a useful tool for screening gene copy numbers of known DBA genes.  相似文献   
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