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91.
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Squamous cell carcinoma (SCC) is the second most common type of skin cancer with potential risks for metastasis and recurrence if left untreated or incompletely excised. This case series study was designed to determine the frequency of incompletely excised SCCs and the related risk factors. A total of 273 SCCs (253 patients) excised in Razi dermatology hospital of Tehran from 2006-2008, were evaluated and were analyzed by Chi-square or t-test. The incidence of incomplete excision was 17.58 % and deep margin involvement was observed in 73% of lesions. Risk factors associated with incomplete excision of SCCs were being female, location of the tumors (in particular the lesions on lateral canthus, upper lip, foot, forehead, cheek, neck, nose and ear), large lesions and grafting method of repair. There was no statistically significant difference for the age, degree of histological differentiation, childhood history of radiotherapy for tinea capitis and the type of anesthesia. More care should be taken for high risk SCCs as complete excision avoids potential risk of recurrence and metastasis.  相似文献   
93.
Benign smooth muscle tumors rarely occur in the head and neck and, to the best of our knowledge, have not been reported in the pterygopalatine fossa. In this report, we describe a 15-year-old adolescent who presented with facial pain and was found to have a large skull base tumor centered in the pterygopalatine fossa. The patient underwent an expanded endonasal endoscopic approach for complete resection of this lesion with resolution of his symptoms. Pathology revealed a well-differentiated smooth muscle neoplasm consistent with a leiomyoma. This case adds to the growing body of literature supporting a role for endoscopic procedures in the treatment of skull base pathologies in pediatric patients.  相似文献   
94.
People with attention-deficit/hyperactivity disorder (ADHD) often experience sleep problems, and these are frequently exacerbated by the methylphenidate they take to manage their ADHD symptoms. Many of the changes to sleep are consistent with a change in the underlying circadian clock. The present study was designed to determine if methylphenidate alone could alter properties of the circadian clock. Young male mice were examined in light-dark cycles and in constant darkness and recordings were performed on behavioral activity, sleep, and electrical activity in the suprachiasmatic nucleus (SCN) of freely moving mice. Methylphenidate in the drinking water (0.08%) significantly increased activity in the mid-to-late night, and led to a delay in the onset of activity and sleep relative to the light-dark cycle. While locomotor levels returned to baseline after treatment ended, the phase angle of entrainment required at least a week to return to baseline levels. In constant darkness, the free-running period of both wheel-running and general locomotor rhythms was lengthened by methylphenidate. When the treatment ended, the free-running period either remained stable or only partially reverted to baseline levels. Methylphenidate also altered the electrical firing rate rhythms in the SCN. It induced a delay in the trough of the rhythm, an increment in rhythm amplitude, and a reduction in rhythm variability. These observations suggest that methylphenidate alters the underlying circadian clock. The observed changes are consistent with clock alterations that would promote sleep-onset insomnia.  相似文献   
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Importance

The middle temporal artery flap is a vascularized periosteal flap that is highly useful for otologic reconstruction including the middle cranial fossa, mastoidectomy defect, and external auditory canal. The course of the artery is close to the external auditory canal and is easily injured during preliminary exposure and elevation of flaps.

Objectives

To describe the course of the middle temporal artery in relation to the external auditory canal and the superficial temporal artery in order to enhance preservation and use in otologic reconstruction.

Design

Dissection of preserved, injected cadaveric temporal bones.

Setting

Anatomical laboratory.

Participants

Seven cadaveric temporal bones.

Intervention

Temporal bones were dissected in a planar manner to identify the middle temporal artery along the squamous temporal bone to its origin. The superior border of the external auditory canal was divided, horizontally, into thirds to create three measurement points. Distances between the middle temporal artery and the bony portion of the external auditory canal were then determined.

Main outcomes and measures

Horizontal diameter of the external auditory canal, distance from the superior-most border of the external auditory canal to the middle temporal artery, various patterns of the middle temporal artery.

Results

The middle temporal artery branched from the superficial temporal artery in all specimens. Mean horizontal diameter of the external auditory canal was 9.97 mm. Mean distances between the bony portion of the external auditory canal and middle temporal artery for the first, second, and third points along the horizontal diameter of the external auditory canal were 1.57, 2.96, and 4.02 mm, respectively. In at least one specimen, the artery dipped into the external auditory canal.

Conclusions and relevance

The middle temporal artery runs closest to the external auditory canal at the anterosuperior border. To preserve the middle temporal artery for use in reconstruction after otologic surgery, the surgeon should avoid dissection superior to the external auditory canal until the artery is positively identified.  相似文献   
98.
Alveolar soft part sarcoma (ASPS) is a rare neoplasm that most commonly presents in the lower extremities. Although ASPS has distinctive histologic features, it may cause diagnostic problems when it arises in unusual locations. To our knowledge, only 1 case of ASPS arising within the breast has previously been reported. Here, we report a second case of primary mammary ASPS. The patient was a 44-year-old woman who presented with a breast mass. Needle biopsy was performed, yielding a polygonal cell lesion with abundant, predominantly xanthomatous cytoplasm. The cells labeled strongly for the histiocytic marker CD68, suggesting a benign macrophage-rich lesion. However, the unusual nature of the lesion as well as the prominence of nucleoli prompted suggestion for an excision. The excision more clearly revealed the lesion's alveolar architecture and demonstrated cells with more eosinophilic cytoplasm, along with the xanthomatous cells. The diagnosis of ASPS was confirmed by electron microscopy, which revealed characteristic membrane-bound rhomboidal crystals, as well as by nuclear labeling for TFE3 protein by immunohistochemistry. With this report, we confirm the utility of a novel immunohistochmical technique for the identification of an ASPS presenting in an unusual locale.  相似文献   
99.
Recent advances in pediatric renal neoplasia   总被引:2,自引:0,他引:2  
  相似文献   
100.
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