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Pancreatoblastoma or infantile pancreatic carcinoma is a rare pancreatic tumor with distinct acinar and squamoid cell differentiation that generally affects infants and young children. Ultrasound and CT scan may be useful but preoperative diagnosis is often quite difficult. The outcome is generally favourable. A such case of 10 years old boy with an abdominal mass is being presented.  相似文献   
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Cantú syndrome (CS), characterized by hypertrichosis, distinctive facial features, and complex cardiovascular abnormalities, is caused by pathogenic variants in ABCC9 and KCNJ8 genes. These genes encode gain‐of‐function mutations in the regulatory (SUR2) and pore‐forming (Kir6.1) subunits of KATP channels, respectively, suggesting that channel‐blocking sulfonylureas could be a viable therapy. Here we report a neonate with CS, carrying a heterozygous ABCC9 variant (c.3347G>A, p.Arg1116His), born prematurely at 32 weeks gestation. Initial echocardiogram revealed a large patent ductus arteriosus (PDA), and high pulmonary pressures with enlarged right ventricle. He initially received surfactant and continuous positive airway pressure ventilation and was invasively ventilated for 4 weeks, until PDA ligation. After surgery, he still had ongoing bilevel positive airway pressure (BiPAP) requirement, but was subsequently weaned to nocturnal BiPAP. He was treated for pulmonary hypertension with Sildenafil, but failed to make further clinical improvement. A therapeutic glibenclamide trial was commenced in week 11 (initial dose of 0.05 mg–1 kg–1 day–1 in two divided doses). After 1 week of treatment, he began to tolerate time off BiPAP when awake, and edema improved. Glibenclamide was well tolerated, and the dose was slowly increased to 0.15 mg?1 kg?1day?1 over the next 12 weeks. Mild transient hypoglycemia was observed, but there was no cardiovascular dysfunction. Confirmation of therapeutic benefit will require studies of more CS patients but, based on this limited experience, consideration should be given to glibenclamide as CS therapy, although problems associated with prematurity, and complications of hypoglycemia, might limit outcome in critically ill neonates with CS.  相似文献   
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Here, we study immune responses in four DNA/MVA-vaccinated macaques following an SHIV-89.6P challenge and a subsequent CD8 cell depletion. Both post-challenge and post-depletion peaks of viremia contracted with the expansion, or re-emergence, of CD8 T cells. Post-depletion, CD8 cells expanded in the presence of higher levels of neutralizing Ab and CD4 help than post-challenge and had superior maturational characteristics as measured by expression of the anti-apoptotic protein Bcl-2, the IL-7 receptor CD127 and co-production of IFN-gamma and IL-2. Pre-challenge and pre-depletion titers of neutralizing Ab correlated inversely with peaks of viremia and directly with peaks for anti-viral CD4 cells. Thus, our results reveal CD8 cells playing a central role, and neutralizing Ab, a supporting role in SHIV-89.6P control. They also suggest a dynamic relationship between neutralizing Ab, antigen load and anti-viral CD4 cells in the maturation of high-quality anti-viral CD8 T cells.  相似文献   
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Primary malignant lymphomas of the breast (PBL) are uncommon constituting only 0.04 to 0.53% of malignant breast neoplasms. We wish to report the clinical, cytological and histologic findings of PBL diagnosed in a 52 years old female.  相似文献   
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Alveolar overdistension during mechanical ventilation causes leukocyte sequestration, leading to lung injury. However, underlying endothelial cell (EC) mechanisms are undefined. In a new approach, we exposed isolated blood-perfused rat lungs to high tidal volume ventilation (HV) for 2 h, then obtained fresh lung endothelial cells (FLEC) by immunosorting at 4 degrees C. Immunoblotting experiments indicated that as compared with FLEC derived from lungs ventilated at low volume (LV), HV markedly enhanced tyrosine phosphorylation (TyrP). The tyrosine kinase blocker, genistein, inhibited this response. HV also induced focal adhesion (FA) formation in FLEC, as detected by immunofluorescent aggregates of the alpha(v)beta(3) integrin that co-localized with aggregations of focal adhesion kinase (FAK). Immunoprecipitation and blotting experiments revealed that HV increased TyrP of the FA protein, paxillin. In addition, HV induced a paxillin-associated P-selectin expression on FLEC that was also inhibited by genistein. However, HV did not increase lung water. These results indicate that in HV, EC signaling in situ causes FA formation and induces TyrP-dependent P-selectin expression. These signaling mechanisms may promote leukocyte-mediated responses in HV.  相似文献   
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Extraskeletal chondroma is a rare entity. A fairly benign condition, it is usually seen in adults. It presents as an enlarging mass, most commonly in the hand. Local excision is the treatment of choice. We present a case of extraskeletal chondroma of hand in a 12 year male child. Its variable histological appearance not infrequently leads to a mistaken diagnosis of chondrosarcoma.  相似文献   
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The study of natural interfaces may provide information necessary to engineer functionally graded biomaterials for bioengineering applications. In this study, the mechanical, structural, and chemical composition variations associated with a region between cementum and dentin were studied with the use of nanoindentation, microindentation, optical microscopy, and Raman microspectroscopy techniques. Three-millimeter-thick transverse sections (N = 5) were obtained from the apical one-third of the roots of sterilized human molars. The samples were ultrasectioned at room temperature with the use of a diamond knife and an ultramicrotome. Longitudinal ground sections of 100 microm thickness were prepared and stained with von Kossa stain to determine the mineralized regions within the molar roots. Raman microspectroscopy was used to determine the relative inorganic content, mainly apatite (PO4(3-)nu1 mode at 960 cm(-1)) and organic content, mainly collagen (C--H stretch at 2940 cm(-1)) between cementum and dentin bulk tissues. The microindentation and nanoindentation results indicated a gradual transition in hardness from cementum to dentin over a width ranging from 100 to 200 microm. However, the variation in hardness data for cementum and dentin by nanoindentation was larger (0.62 +/- 0.21, 0.77 +/- 0.14 GPa) than from microindentation (0.49 +/- 0.03, 0.69 +/- 0.07 GPa). Within the 100 to 200 microm region there was a 10 to 50 microm fibrillar hydrophilic cementum-dentin junction (CDJ) with mechanical properties significantly lower than either the cementum or the dentin side of CDJ. Light microscopy revealed a 100 to 200 microm translucent region between cementum and dentin. Raman microspectroscopy results showed a variation in organic and inorganic composition 80 to 140 microm wide. It was concluded that a morphologically and biomechanically different CDJ lies within a wider cementum-dentin interphase. Hence, cementum, dentin, and the interphase can be classified as a functionally graded dental tissue within the root of a tooth.  相似文献   
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