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121.

Background

Rituximab, an anti-CD20 antibody that targets B cells, is a promising agent against steroid-dependent and steroid-resistant nephrotic syndrome in children.

Case-Diagnosis/Treatment

We report a 3-year-old boy who presented with atypical Pneumocystis jiroveci pneumonia (PCP) following administration of rituximab for refractory nephrotic syndrome. He had received cyclosporine and daily prednisolone for over 1?year. Following rituximab therapy, a hazy shadow was observed on his chest X-ray. Chest-computed tomography revealed multiple nodular lesions in bilateral lungs, although his clinical symptoms were subtle. PCR analysis demonstrated the presence of Pneumocystis DNA in his bronchoalveolar lavage. Lung wedge resection of the nodular lesion exhibited granulomas containing a few cysts of P. jiroveci that primarily consisted of T cells and histiocytes and lacked B cells. A deficiency of B cells following rituximab treatment suggests a dramatic effect on the immune response and, therefore, could result in granulomatous PCP. Nodular granulomatous lesions of PCP comprise an emerging concept previously reported in adults with hematological disease, bone marrow transplant, or treatment with rituximab. We report the first pediatric case of nodular PCP. Granulomatous PCP can be life-threatening. Moreover, bronchoalveolar lavage often fails to demonstrate the presence of P. jiroveci DNA. Wedge biopsy is warranted for definitive diagnosis. Our patient fully recovered with sulfamethoxazole/trimethoprim treatment because of early detection.

Conclusions

The indication of rituximab for refractory nephrotic syndrome has increased recently. Therefore, recognition of the risk of atypical PCP is important. Our findings suggest that PCP prophylaxis should be considered following rituximab therapy.  相似文献   
122.
For the past three decades, surgery of glomus jugulare tumors (GJTs) has been characterized by extensive combined head and neck, neuro-otologic, and neurosurgical approaches. In recent years, the authors have modified the operative technique to a less invasive approach for preservation of cranial nerves while achieving satisfactory tumor resection. We evaluated and compared the clinical outcomes of our current less invasive approach with our previous more extensive procedures. The clinical records of 39 cases of GJT surgically treated between 1992 and 2011 were retrospectively reviewed. The less invasive transjugular approach with Fallopian bridge technique (LI-TJ) was used for the most recent five cases. The combined transmastoid–transjugular and high cervical (TM-HC) approach was performed in 30 cases, while four cases were treated with a transmastoid–transsigmoid approach with facial nerve translocation. Operative technique, extent of tumor resection, operating time, hospital stay, and morbidity were examined through the operative records, and a comparison was made between the LI-TJ cases and the more invasive cases. No facial nerve palsy was seen in the LI-TJ group while the TM-HC group demonstrated six cases (17.6 %) of facial palsy (House–Brackmann facial nerve function grading scale grade II and III). The complication rate was 0 % in the LI-TJ group and 16.7 % in the more invasive group. The mean operative time and hospital stay were shorter in the LI-TJ group (6.4 h and 4.3 days, respectively) compared with the more invasive group (10.7 h and 8.0 days, respectively). The LI-TJ approach with Fallopian bridge technique provided adequate tumor resection with cranial preservation and definitive advantage over the more extensive approach.  相似文献   
123.
124.
Aortic arch thrombosis (AAT) of the neonate is rare but life-threatening by fatal compromise associated with thrombotic obstruction of the ascending aorta. We report a neonate with AAT who demonstrated a severe coarctation of the aorta and cerebral hypo-perfusion immediately after birth. Echocardiography confirmed the diagnosis of AAT on the findings of a large thrombus located on the transverse arch and blocking the cervical arterial branches. Low-molecular-weight heparin reduced the size of the thrombus and improved the hemodynamics of coarctation and cerebral perfusion. Echocardiography is a powerful tool to make a diagnosis and to monitor the size and regression of AAT.  相似文献   
125.
Epstein–Barr virus (EBV) is known to be associated with the development of lymphomas in immunocompromised patients. Recently, age-related immune impairment has been recognized as a predisposing factor in the development of EBV-driven lymphoproliferative disorders (LPDs) in elderly patients without any known immunodeficiency or prior lymphoma. In approximately 70 % of reported cases, the affected sites have been extranodal, such as the skin, lung, tonsil and stomach. However, age-related EBV-associated B cell (EBV + B cell) LPD is extremely rare in the oral cavity. Here we report a 71-year-old Japanese man who developed an EBV + B cell LPD resembling classical Hodgkin lymphoma (CHL)—so-called polymorphous subtype—of the mandible. Histopathologically, infiltration of large atypical lymphoid cells including Hodgkin or Reed-Sternberg-like cells into granulation tissue with marked necrosis was found in the mandibular bone. Immunohistochemical analysis revealed that the large atypical Hodgkin or Reed-Sternberg-like cells were CD3–, CD15–, CD20+, CD30+ and Epstein–Barr virus (EBV)-latent infection membrane protein-1 (LMP-1)+. In situ hybridization (ISH) demonstrated EBV-encoded small RNA (EBER) + in numerous Hodgkin or Reed-Sternberg-like cells. EBNA-2 was detected by polymerase chain reaction (PCR) using an extract from the formalin-fixed, paraffin-embedded specimen. To our knowledge, this is the first reported case of the polymorphous subtype of age-related EBV + B cell LPD affecting the mandible.  相似文献   
126.
127.

Introduction

Juvenile xanthogranuloma (JXG) preferentially occurs in childhood, and its characteristics have been thought to be benign and with slow growth. JXG is classified as an inflammatory disease, which forms multiple lesions in the patients’ head, neck, and other organs and typically skin. JXG is rare, and few case reports have been published in the past, particularly with multiple intracranial lesions, which as in our case, is an extremely rare finding.

Case

Patient is a 4-year-old boy who presented with polydypsia and polyuria for 1 year. He had been followed up only under l-deamino-8-d-arginine vasopressin until he started vomiting and his level of consciousness deteriorated. Then, magnetic resonance imaging (MRI) revealed multiple intracranial lesions. He underwent biopsy via small craniotomy, and pathology was confirmed as juvenile xanthogranuloma. The patient received chemotherapy, in complete compliance with JLSG-02 protocol.

Findings

JXG is characteristic with homogenous enhancement with contrast matter and, most importantly, high intensity on diffusion-weighted image (DWI). The DWI was high when the degree of diffusion of water is restricted, as seen in inflammation and, additionally, the change of intensity after administration of steroid would reflect its anti-inflammatory nature. However, though the steroid therapy made high-intensity lesions decrease signal intensity, the size and the number of lesions did not change at all. As we expected, after we stopped steroid administration to the patient, his consciousness deteriorated and we found again the very-high-intensity lesions. We consider the intensity on DWI to reflect progression of the lesions.  相似文献   
128.
129.
Numerous studies have reported that perceptual grouping affects the pre‐attentive processing of sound omission in a sequence of tones. However, it remains unclear whether or not the perceptual grouping and musical experience affect the attentive processing of sound omission. To this end, we created a sequence of loud (L) and soft (S) tones grouped as ‘LLSLLS…’ and a random sequence of the L and S tones. The omission of the L tones was inserted pseudo‐randomly in the random sequence, and there were two positions at which it was inserted. For within‐group omission, the omission was after the first L tone within the ‘LLS’ pattern. For between‐group omission, the omission was inserted between the patterns. The brain response to the omission in musicians and non‐musicians was measured using magnetoencephalography. During the magnetoencephalography measurement, the subjects' performance in a task to detect the omission was faster in the random sequence than in the group sequence. Source analysis showed that the omission in the random sequence caused greater activity than that in the group sequence. The increase was found in the right inferior parietal lobe in musicians, whereas it was found in the left superior temporal gyrus in non‐musicians. These results suggest that the attentive processing of perceptual grouping might implicate the left superior temporal gyrus or right inferior parietal lobe, depending on musical experience.  相似文献   
130.
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