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21.
Polyglutamine (polyQ) diseases are a growing class of inherited neurodegenerative diseases including Huntington's disease, which are caused by abnormal expansions of the polyQ stretch in each unrelated disease protein. The expanded polyQ stretch is thought to confer toxic properties on the disease proteins through alteration of their conformation leading to pathogenic protein-protein interactions including oligomerization and/or aggregation. Hypothesizing that molecules with selective binding affinity to the expanded polyQ stretch may interfere with the pathogenic properties, we previously identified Polyglutamine Binding Peptide 1 (QBP1) from combinatorial peptide phage display libraries. We show here that a tandem repeat of the inhibitor peptide QBP1, (QBP1)(2), significantly suppresses polyQ aggregation and polyQ-induced neurodegeneration in the compound eye of Drosophila polyQ disease models, which express the expanded polyQ protein under the eye specific promoter. Most importantly, (QBP1)(2) expression dramatically rescues premature death of flies expressing the expanded polyQ protein in the nervous system, resulting in the dramatic increase of the median life span from 5.5 to 52 days. These results suggest that QBP1 can prevent polyQ-induced neurodegeneration in vivo. We propose that QBP1 prevents polyQ oligomerization and/or aggregation either by altering the toxic conformation of the expanded polyQ stretch, or by simply competing with the expanded polyQ stretches for binding to other expanded polyQ proteins. The peptide inhibitor QBP1 is a promising candidate with great potential as a therapeutic molecule against the currently untreatable polyQ diseases.  相似文献   
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The adjuvant effect of mannan-coated liposomes on human immunodeficiency virus type-1 (HIV-1) DNA vaccine and the mechanism of this enhancement were studied. Coating of cationic liposomes with mannan significantly enhanced the ability of this vaccine to induce an HIV-specific delayed-type hypersensitivity (DTH) response. HIV-specific cytotoxic T-cell (CTL) activity elicited by DNA vaccination was also significantly enhanced with the mannan-liposome cocktail. This mannan-liposome-mediated activity was greatly inhibited by in vivo injection of anti-interferon (IFN)-gamma antibody, which suggests that IFN-gamma plays an important role in this HIV-specific immune response. The results of both isotype-specific antibody and cytokine analysis revealed that mannan-liposome-mediated DNA vaccination enhances Th1-mediated immunity.  相似文献   
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We want to report on our experiences with the percutaneous trephination using a 2.35 mm round dental drill with serrated saws around it, a Rosenbohrer. It is a methodically similar activity as described by J. Zentner [11].From 1981 to 1992 519 patients were treated and 546 trephinations were performed.At the beginning this treatment was only used in connection with intracerebral bleedings and biopsies.In a considerable short time the indication could be extended to the subdural hematoma, tumor cyst, obstructive hydrocephalus as well as to the abscess and the subdural epyema.The rate of infection was 1.28% and the risk of bleeding 0.36%.In our opinion the advantages of this small electrical trephination are the easy handling, the universal use and mobility and the avoidable risk of anesthesia as well as the sterilisation at the same time and the stopping of blood, caused by the contact surface friction.  相似文献   
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We report herein the case of a 32-year-old woman who underwent distal gastrectomy with D2 lymph node dissection for gastric cancer. Microscopic examination of the resected specimen revealed signet-ring cell carcinoma of the stomach with lymph node metastases, and endosalpingiosis in the normal lymph nodes. There was no evidence of malignancy in the peritoneal cavity. To our knowledge, no other case of endosalpingiosis in the lymph nodes along the stomach has ever been reported. The possible significance of endosalpingiosis is discussed following this case report.  相似文献   
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Aims of this study were to functionally and histologically determine the localization of ganglia that distribute inhibitory nerves to the penile corpus cavernosum in dogs. In isolated corpus cavernosa from seven control dogs contracted with endothelin-1, transmural electrical stimulation (5 Hz for 40 s) elicited contractions which were reversed to relaxations by prazosin. The relaxation was abolished by NG-nitro-l-arginine (l-NNA), a nitric oxide (NO) synthase inhibitor, and restored by l-arginine. Parts of bilateral pelvic nerve plexuses running to the penis were surgically denervated in anesthetized three dogs, or the bilateral neuronal tissues close to the corpus cavernosum were removed for denervation in seven dogs. One week after the operation, the dogs were sacrificed. Denervation of pelvic plexus did not attenuate neurogenic relaxations, whereas denervation of the distal portion abolished the responses. In the tissues close to the corpus cavernosum excised for denervation, ganglia containing abundant nerve cells and fibers stained by nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase method were histochemically detected. One week after the denervation, there were no NADPH diaphorase-positive nerve fibers in the trabecula of corpus cavernosum. It is concluded that neurogenic relaxations of canine corpus cavernosum are mediated by NO synthesized from l-arginine in nerve terminals, and this nerve is originated from ganglia located close to the corpus cavernosum but not directly from the pelvic nerve plexus.  相似文献   
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Sj?gren's syndrome is a complex autoimmune disorder, that occurs almost exclusively in females, induces extensive lymphocyte accumulation in lacrimal and salivary glands, and represents one of the leading causes of dry eye and mouth in the world. The purpose of this study was to determine whether the profound, gender-related differences observed in the magnitude of exocrine gland inflammation in Sj?gren's syndrome may also be found in tissues of mouse models of this disorder. Lacrimal and submandibular glands were obtained from adult MRL/lpr, MRL+/+ (MRL+), NZB/NZW F1 (F1), C3H/lpr, C3H/gld (gld), C57BL/6-lpr/lpr [B6/lpr; with (bcl-2(+)/lpr) or without (bcl-2(-)/lpr) bcl-2 transgene insertion] and nonobese diabetic (NOD) mice after the onset of autoimmune disease, and processed for microscopy and image analysis. Our results showed that: (1) the extent of inflammation was significantly greater in lacrimal glands of female MRL/lpr, MRL+, F1, C3H/lpr and gld mice, and salivary glands of female MRL+, F1 and gld mice, relative to those of males; (2) the severity of inflammation in NOD mice showed a tissue-specific pattern: inflammation was far worse in lacrimal glands of males, whereas immune pathology was far greater in salivary tissues in females; and (3) no gender-related variations were present in the degree of inflammation in lacrimal glands of bcl-2(+)/lpr and bcl-2(-)/lpr mice or in submandibular tissues of MRL/lpr, C3H/lpr, bcl-2(+)/lpr and bcl-2(-)/lpr mice. Our findings demonstrate that gender-, strain- and tissue-related differences exist in the extent of inflammation in several mouse models of Sj?gren's syndrome.  相似文献   
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During a sparrow-pecking and twisting-needle manipulation to the acupoints BL 23, 24 and 25 for an induction of "Qi", it was found that some transparent materials were binding to the needles after removed from the volunteer's skin. Electron-microscopical analysis of the transparent materials revealed that they corresponded to the injured fascia made up of collagen fibers, elastic fibers, fibroblasts, adipocytes and mast cells. Rarely were nerve fiber-like structures observed in the materials. Immunohistochemically, calcitonin gene-related peptide-positive nerve fibers could be demonstrated in the acupoint BL 24 associated fascia. A possible functional relationship between the needle manipulation and the induction of Qi-sensation is discussed along with the acupoint tissue constitution.  相似文献   
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