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71.
Intraductal papillary-mucinous carcinoma (IPMC) is a recently recognized pancreatic tumor and this is the first report to present two patients with IPMC complicating tumor thrombi in the portal vein. Two women, a 74- and a 55-year-old, each revealed a round, cystic and well-demarcated tumor of the pancreas in an abdominal computed tomography (CT). However, the inner lumen of the splenic and portal veins was insufficiently stained during iv-infusion of the contrast medium, suggesting the presence of tumor thrombi. Owing to this information, the presence of tumor thrombus was investigated and correctly identified during laparotomy, and it was completely removable together with the primary pancreatic tumor. The resected tumors showed expansive growth because mucin and tumor tissues rose up when they were cut. Microscopically, the tumor was diagnosed as adenocarcinoma without ovarian-like stroma, and the final diagnosis of branch type of IPMC was made for the two patients. However, within one postoperative year, both patients developed liver metastasis. Although IPMC is known as having a lower potential for metastasis or invasion, the tumor thrombi can form when it reveals an expansive growth suggesting a high inner pressure. In addition, a higher possibility for subsequent liver metastasis should be anticipated after the tumor forms a thrombus in the portal vein.  相似文献   
72.
The ultrastructural localization of rat corticoliberin (rCRF) and methionine-enkephalin octapeptide (Met-Enk-8) in the external layer of the rat median eminence were examined by double-immunogold labeling with anti-rCRF and anti-Met-Enk-8 sera labeled with small-sized (Gs) and medium-sized (Gm) gold particles, respectively. Two types of immunolabeled terminals were distinguished: one type with small granules (70 nm) labeled with Gs, and the other with large granules (100 nm) labeled with Gm. In both types, however, some granules were labeled with both Gs and Gm.  相似文献   
73.
Twelve patients with nephrotic syndrome (NS) in Henoch-Schoenlein (HS) nephritis were treated with a high dose of intravenous methylprednisolone (MP) on each of nine alternate days followed by oral prednisolone for 4 to 6 months. Renal biopsy was performed on 10 of the 12 patients. The glomerular change in 5 patients, which was accompanied by crescents and/or sclerosis, with NS and acute nephritic syndrome (ANS) at onset, was more severe than that of the other 5 patients with NS and hematuria at onset. The renal insufficiency or hypertension in these 5 patients with NS and ANS improved within 2 weeks on this MP therapy. After a mean follow-up period of 40.5 months, all patients except 2 revealed normal physical findings and renal function as well as urinary findings. Repeated biopsies in the 2 patients with NS and ANS at onset demonstrated an improved renal pathology in comparison with their initial biopsies. No severe side effects related to high-dose intravenous MP followed by oral prednisolone therapy were encountered in any of the patients. Our results suggest that high-dose intravenous MP therapy can lead to a favorable outcome in patients with NS in HS nephritis.  相似文献   
74.
Sir, Lysophosphatidic acid (LPA) has been suggested to be involvedin the pathogenesis of a number of disease states, includingcancer and atherosclerosis, through its induction of a widerange of (patho)physiological events, such as cellular survival,proliferation, migration, change in morphology and extracellularmatrix deposition [1,2]. These actions of LPA are believed tobe mediated via specific cell-surface G protein-coupled receptorsand the downstream intracellular signalling pathways [1,2].The important role of LPA is  相似文献   
75.
Summary Immunolocalization of type III procollagen (pro III) in normal and cirrhotic human liver was studied using rabbit antiserum specific for bovine type III procollagen aminopeptide. The material examined was deparaffinized, trypsin-treated hepatic tissue sections from 28 autopsy cases, including 19 cirrhotic and 9 normal liver donors. Immunostaining, performed by the unlabeled peroxidase-antiperoxidase antibody technique demonstrated that extracellular matrices corresponding to perisinusoidal reticulin, collagen in periportal areas, and blood vessel walls were the common sites of pro III antigenicity in both normal and cirrhotic liver. Moreover, in the cirrhotic liver, the fibrous septa of pseudolobules, and cytoplasm of hepatocytes and sinusoidal cells were positive when stained for pro III peptide. The differential counts of pro III positive cells in cirrhotic liver, however, revealed that the average ratio of these hepatocytes to sinusoidal cells was 25 to 1, indicating complete dominance of hepatocytes with respect to stainability for pro III peptide compared to sinusoidal cells. In hepatocellular carcinomas co-existing with cirrhosis, neoplastic cells also displayed pro III antigenicity.These data suggest that hepatocytes of cirrhotic liver and hepatocellular carcinoma cells play a significant role in type III collagen synthesis in vivo.The paper on this problem was read at the International Symposium on Pathobiology of Hepatic Fibrosis held in Matsue, Japan, on June 16, 1985  相似文献   
76.
77.
Summary Immunoreactive TRH-containing neurons and their synaptic associations were studied electron microscopically in the paraventricular nucleus (PVN) and dorsomedial nucleus (DMH) of the rat hypothalamus. In propylthiouracil (PTU)-treated rats, the immunoreactive cell bodies in the PVN appeared to be activated, showing a hypertrophic perikaryon, well developed Golgi bodies and numerous secretory granules. No such alterations were evident in the TRH neurons in the DMH. These findings suggest that the PVN-TRH neurons are involved in the hypothalamic-hypophysial-thyroid axis. Further, it was shown that unlabeled nerve terminals containing small and large clear vesicles make synaptic contacts with the TRH perikarya in the PVN. Thus it is likely that PVN-TRH neurons are regulated both by thyroid hormones and by other neuronal signals. In the DMH, unlabeled nerve terminals containing small and large clear vesicles, and immunoreactive terminals form synapses with TRH neurons. Thus the DMH-TRH neurons may be under dual neuronal control. It was further noted that in the DMH and PVN, TRH nerve terminals make synaptic contacts with other unlabeled neurons. It is evident that TRH acts as a neurotransmitter or neuromodulator, although the origin of TRH terminals should be elucidated.  相似文献   
78.
An electron microscopic study showed by using a dual immunolabeling technique that in the suprachiasmatic nucleus of the rat, axon terminals immunoreactive for neuropeptide Y (NPY) made synaptic contacts upon neurons immunoreactive for vasoactive intestinal polypeptide (VIP). Diaminobenzidine (DAB)-labeled NPY axon terminals made synaptic contacts on silver-gold-labeled VIP perikarya and dendritic processes. The presynaptic NPY terminals contained many small clear vesicles and a few cored vesicles labeled with DAB chromogen. At the synaptic portion, a symmetrical thickening of the pre- and post-synaptic membranes was evident.  相似文献   
79.
Recent studies have suggested that spinal G-protein-coupled, inwardly rectifying K+ (GIRK) channels play an important role in thermal nociception and the analgesic actions of morphine and other agents. In this study, we show that spinal GIRK channels are activated by an endogenous neurotransmitter using whole-cell patch-clamp recordings from substantia gelatinosa (SG) neurones in adult rat spinal cord slices. Although repetitive stimuli applied to the dorsal root did not induce any slow responses, ones focally applied to the spinal dorsal horn produced slow inhibitory postsynaptic currents (IPSCs) at a holding potential of −50 mV in about 30% of the SG neurones recorded. The amplitude and duration of slow IPSCs increased with the number of stimuli and decreased with removal of Ca2+ from the external Krebs solution. Slow IPSCs were associated with an increase in membrane conductance; their polarity was reversed at a potential close to the equilibrium potential for K+, calculated from the Nernst equation. Slow IPSCs were blocked by addition of GDP-β-S into the patch-pipette solution, reduced in amplitude in the presence of Ba2+, and significantly suppressed in the presence of an antagonist of GIRK channels, tertiapin-Q. Somatostatin produced an outward current in a subpopulation of SG neurones and the slow IPSC was occluded during the somatostatin-induced outward current. Moreover, slow IPSCs were significantly inhibited by the somatostatin receptor antagonist cyclo-somatostatin. These results suggest that endogenously released somatostatin may induce slow IPSCs through the activation of GIRK channels in SG neurones; this slow synaptic transmission might play an important role in spinal antinociception.  相似文献   
80.
Analysis of the allergenic components of the house dust mite Dermatophagoides farinae was performed. Four different types of proteins reactive with human anti-mite IgE antibodies were identified as four distinct radioprecipitins in radioimmunoelectrophoresis. These were designated as mite allergen reactive with human IgE antibodies (Me) Me 1, Me 2, Me 3, and Me 4 according to their electrophoretic mobility from the slower to the faster. Me 1 and Me 2 were the first and the second prevailing allergens, respectively, in 133 atopic patients subjected to the study. Me 1, on purification by gel filtration and anion exchange chromatography, elicited a single radioprecipitin by radioimmunoelectrophoresis. Me 1 also elicited a single band in sodium dodecyl sulphate-polyacrylamide gel electrophoresis and a single peak in high-performance liquid chromatography. Both methods elicited identical values of 17,000 daltons for the molecular weight of Me 1. The isoelectric point of Me 1 was suggested to be 8.0. Me 1 elicited higher skin reactions compared to that obtained by the crude mite extract when it was assessed in seven atopic patients by serial titration intradermal skin testing.  相似文献   
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