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61.
Caveolins—caveolin‐1, ‐2, ‐3 (Cav1, 2, 3)—are major components of caveolae, which have diverse functions. Our recent study on the temporomandibular joint (TMJ) revealed expressions of Cav1 and muscle‐specific Cav3 in some synovial fibroblast‐like type B cells with well‐developed caveolae. However, the involvement of Cav3 expression in the differentiation and maturation of type B cells remains unclear. The present study therefore examined the chronological alterations in the localization of Cav3 in the synovial lining cells of the rat TMJ during postnatal development by immunocytochemical techniques. Observations showed immature type B cells possessed a few caveolae with Cav1 but lacked Cav3 protein at postnatal day 5 (P5). At P14, Cav3‐immunopositive type B cells first appeared in the synovial lining layer. They increased in number and immunointensity from P14 to P21 as occlusion became active. In immunoelectron microscopy and double immunolabeling with heat shock protein 25 (Hsp25) and Cav3, coexpressed type B cells developed rough endoplasmic reticulum and numerous caveolae, while the Cav3‐immunonegative type B cell with Hsp25 immunoreaction possessed few of these. Results suggest that Cav3 expression, which is closely related to added functional stimuli, reflects the differentiation of the type B synoviocytes. Anat Rec, 291:233–241, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
62.
A case of osteosarcoma in pelvic bone following radiation therapy for prostate cancer is reported. A 74-year-old patient was diagnosed with prostate cancer 10 years ago and started on the endocrine therapy with LH-RH agonist. He had no apparent distant metastasis, and received radiation therapy 8 years ago. He has complained of low back pain since several months ago. A high uptake on bone scintigram and osteolytic and osteoblastic damages on CT were noted in pubic bone and sacrum. The PSA level was less than 0.2 ng/ml. Pathohistological diagnosis by biopsy of the pubic bone was chondroblastic type osteosarcoma, showing an atypical cell proliferation with osteoid. Immunostaining for nonepithelial marker vimentin was positive. He underwent heavy ion radiation therapy for osteosarcoma at the National Institute of Radiological Sciences. Osteosarcoma is one of the rare delayed complications after radiation therapy and requires biopsy for correct diagnosis.  相似文献   
63.
Platinum (Pt) levels were determined in various tissues and body fluids obtained from a patient who died 181 days after cisplatin overdosing. The symptoms of cisplatin overdose, however, might have almost disappeared by day 40, and the patient’s death was ascribed to the recurrence of malignant lymphoma. Determination of Pt derived from cisplatin was performed by electrospray ionization mass spectrometry (ESI-MS) using silver (Ag) as internal standard. Pt and Ag complexed with diethyldithiocarbamate (DDC) in wetashed blood, and tissue solutions were extracted into isoamyl alcohol, and then acidified with oxalic acid. By injecting an aliquot of the isoamyl alcohol layer into a mass spectrometer in the direct flow injection mode, the quantitation was performed using the signals of Pt(DDC)3 + and Ag(DDC)2 + at m/z 639 and 403, respectively. The Pt levels ranged from 25ng/ml in blood to 2050ng/g wet weight in the liver of the patient, indicating that Pt remained at high levels in tissues, even after a period as long as 181 days after cisplatin overdosing.  相似文献   
64.
65.
Ursodeoxycholic acid (UDCA) was administered to 10 patients diagnosed as having primary biliary cirrhosis (PBC) after liver biopsy. Eight patients were anicteric, and two were icteric cases. One patient was in stage I, seven were in stage II, one in stage I-III, and one in stage III-IV of Scheuer's classification. Six hundred milligrams of UDCA were administered orally after meals three times daily to all of the patients for more than 1 yr. The period of UDCA administration ranged from 6 to 41 months. The major findings are as follows: 1) in six out of seven patients with pruritus, itching disappeared 1 month after administration of UDCA; 2) both serum alkaline phosphatase and gamma-glutamyltranspeptidase levels began decreasing significantly the first month after the onset of UDCA treatment, and continued decreasing throughout the treatment; 3) GOT and GPT levels also decreased significantly during the administration of UDCA, compared with before-treatment levels; 4) in one icteric patient with portal hypertension, although serum biliary enzyme levels improved after treatment, serum bilirubin level got worse, and the patient died of esophageal variceal hemorrhage. In another icteric case, biliary and bilirubin levels improved slightly after treatment; 5) antimitochondrial antibody titer decreased in four cases, but IgM levels and other immunological parameters were not changed; 6) serum UDCA increased significantly during UDCA treatment; in particular, glyco-UDCA occupied up to 40% of the total bile acid and CDC decreased to 25%; 7) portal inflammation activity decreased in all five patients who had undergone follow-up liver biopsy, more than 1 yr after UDCA administration--bridging fibrosis decreased in three cases; and 8) no side effects were observed in any of the cases. Although large-scale, randomized, controlled, double-blind tests are necessary, it is speculated that the long-term administration of UDCA is a safe and effective treatment for the improvement of biliary enzyme levels and pruritus in anicteric PBC.  相似文献   
66.

Objective

Low wall shear stress (WSS) has been reported to be associated with accelerated atherosclerosis, aneurysm growth, or rupture. We evaluated the geometry of aortic arch aneurysms and their relationship with WSS by using the 4-dimensional flow magnetic resonance imaging to better characterize the saccular aneurysms.

Methods

We analyzed the geometry in 100 patients using multiplanar reconstruction of computed tomography. We evaluated WSS and vortex flow using 4-dimensional flow magnetic resonance imaging in 16 of them, which were compared with 8 age-matched control subjects and eight healthy young volunteers.

Results

Eighty-two patients had a saccular aneurysm, and 18 had a fusiform aneurysm. External diameter/aneurysm length ratio and sac depth/neck width ratio of the fusiform aneurysms were constant at 0.76 ± 0.18 and 0.23 ± 0.09, whereas those of saccular aneurysms, especially those involving the outer curvature, were higher and more variable. Vortex flow was always present in the aneurysms, resulting in low WSS. When the sac depth/neck width ratio was less than 0.8, peak WSS correlated inversely with luminal diameter even in the saccular aneurysms. When this ratio exceeded 0.8, which was the case only with the saccular aneurysms, such correlation no longer existed and WSS was invariably low.

Conclusions

Fusiform aneurysms elongate as they dilate, and WSS is lower as the diameter is larger. Saccular aneurysms dilate without proportionate elongation, and they, especially those occupying the inner curvature, have higher and variable sac depth/neck width ratio. When this ratio exceeds 0.8, WSS is low regardless of diameter, which may explain their malignant clinical behavior.  相似文献   
67.
The neural correlates of successful retrieval on tests of word stem recall and recognition memory were compared. In the recall test, subjects viewed word stems, half of which were associated with studied items and half with unstudied items, and for each stem attempted to recall a corresponding study word. In the recognition test, old/new judgments were made on old and new words. The neural correlates of successful retrieval were identified by contrasting activity elicited by correctly endorsed test items. Old > new effects common to the two tasks were found in medial and lateral parietal and right entorhinal cortex. Common new > old effects were identified in medial and left frontal cortex, and left anterior intra-parietal sulcus. Greater old > new effects were evident for cued recall in inferior parietal regions abutting those demonstrating common effects, whereas larger new > old effects were found for recall in left frontal cortex and the anterior cingulate. New > old effects were also found for the recall task in right lateral anterior prefrontal cortex, where they were accompanied by old > new effects during recognition. It is concluded that successful recall and recognition are associated with enhanced activity in a common set of recollection-sensitive parietal regions, and that the greater activation in these regions during recall reflects the greater dependence of that task on recollection. Larger new > old effects during recall are interpreted as reflections of the greater opportunity for iterative retrieval attempts when retrieval cues are partial rather than copy cues.  相似文献   
68.
Caveolae are involved in clathrin-independent endocytosis, transcytosis, signal transduction, and tumor suppression – all of which depend on their main constituent protein caveolin families. The periodontal Ruffini ending has been reported to develop a caveola-like structure on the cell membrane of both the axon terminals and Schwann sheaths, suggesting the existence of an axon–Schwann cell interaction in the periodontal Ruffini endings. However, little information is available concerning the functional significance of these caveolae. The present study was undertaken to examine the immunolocalization of caveolin-1, -3 (Cav-1, Cav-3) and Ca2+-ATPase in the periodontal Ruffini endings of the rat incisor. Decalcified sections of the upper jaws were processed for immunocytochemistry at the levels of light and electron microscopy. Some immunostained sections were treated with histochemistry for nonspecific cholinesterase (nChE) activity. Observations showed the periodontal Ruffini endings were immunopositive for Cav-1, but not Cav-3. Immunoreactive products for Cav-1 were confined to caveola-like structures in the cell membranes of the cytoplasmic extensions and cell bodies of the terminal Schwann cells associated with the periodontal Ruffini endings. However, the axonal membranes of the terminals did not express any Cav-1 immunoreaction. Double staining with Ca2+-ATPase and either protein gene product 9.5 (PGP 9.5) or S-100 protein disclosed the co-localization of immunoreactions in the axonal branches of the periodontal Ruffini endings, but not in the terminal Schwann cells. As Ca2+ plays an important role in mechanotransduction, these characteristic immunolocalizations show Cav-1/Ca2+-ATPase might be involved in the quick elimination of intracellular Ca2+ in mechanotransduction.  相似文献   
69.
The insular cortex plays important roles in vocal communication, but the origin of auditory input to the insular cortex has not been fully clarified. Here we studied the auditory thalamic input to the insular cortex using mice as a model system. An insular auditory field (IAF) has recently been identified in mice. By using retrograde neuronal tracing, we identified auditory thalamic neurons projecting to the IAF, primary auditory cortex (AI), and anterior auditory field (AAF). After mapping the IAF, AAF, and AI by using optical imaging, we injected a distinct fluorescent tracer into each of the three fields at frequency‐matched locations. Tracer injection into the IAF resulted in retrogradely labeled cells localized ventromedially in the lemniscal division, i.e., the ventral subdivision of the medial geniculate body (MGv). Cells retrogradely labeled by injections into the AAF were primarily found in the medial half of the MGv, whereas those from AI injections were located in the lateral half, although some of these two subsets were intermingled within the MGv. Interestingly, retrogradely labeled cells projecting to the IAF showed virtually no overlap with those projecting to the AAF or the AI. Dual tracer injections into two sites responding to low‐ and high‐frequency tones within each of the three auditory fields demonstrated topographic organizations in all three thalamocortical projections. These results indicate that the IAF receives thalamic input from the MGv in a topographic manner, and that the MGv–IAF projection is parallel to the MGv–AAF and MGv–AI projections. J. Comp. Neurol. 522:1373–1389, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
70.
Because some users develop depigmentation after the use of melanogenesis‐inhibiting products containing the quasi‐drug ingredient Rhododenol, Japanese Dermatological Association (JDA) established a Special Committee on the Safety of Cosmetics Containing Rhododenol on July 17, 2013 and management guide for dermatologists has been updated on the website in order to delineate the diagnostic criteria for Rhododenol‐induced leukoderma and provides a broad guide for standard treatment based on current knowledge. This guide is produced on the basis of the guide (version 7) updated on June 20, 2014 in the website. Rhododenol‐induced leukoderma refers to depigmentation of varying severity that develops after the use of cosmetics containing Rhododenol, mainly at the site of use. In most cases, repigmentation of part or all the affected area is evident after discontinuation. Histopathologically cellular infiltration around the hair follicles and melanophages are present in most cases. The number of melanocytes in the lesion is declined but not totally absent in most cases. Rhododenol itself is a good substrate for tyrosinase, resulting in the formation of Rhododenol metabolites (e.g., Rhododenol quinone). Melanocytes are damaged by Rhododenol metabolites during the subsequent metabolic process. The continued use of cosmetics containing Rhododenol thus induces tyrosinase activity‐dependent cytotoxicity in melanocytes in the epidermis at application sites, resulting in decreasing the amount of melanin produced by melanocytes; the addition of some other factor to this process is believed to subsequently cause the decrease or disappearance of melanocytes themselves from the epidermis.  相似文献   
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