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81.
Although posterior urethral valves are predominant as a cause of obstructive uropathy in children, anterior urethral valves may also appear as the underlying etiologic factor in end-stage renal disease that results from obstruction. Two cases are presented of anterior urethral valve patients that were admitted with end-stage renal disease. The first case was successfully treated with diverticulectomy and urethral reconstruction in preparation for renal transplantation. The second case, however, had been on cystostomy drainage for 6 years and also had a contracted bladder. A more extensive lower urinary tract reconstruction was delayed. Children with poor stream and recurrent infections should be evaluated carefully and anterior urethral valve or diverticula should be considered in differential diagnosis of obstructive lesions.  相似文献   
82.

Background:

Oxidative stress is a mediator of secondary injury to the spinal cord following trauma.

Objective:

To investigate the putative neuroprotective effect of α-lipoic acid (LA), a powerful antioxidant, in a rat model of spinal cord injury (SCI).

Methods:

Wistar albino rats were divided as control, vehicle-treated SCI, and LA-treated SCI groups. To induce SCI, a standard weight-drop method that induced a moderately severe injury (100 g/cm force) at T10 was used. Injured animals were given either 50 mg/kg LA or saline at 30 minutes postinjury by intraperitoneal injection. At 7 days postinjury, neurologic examination was performed, and rats were decapitated. Spinal cord samples were taken for histologic examination or determination of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity, and DNA fragmentation. Formation of reactive oxygen species in spinal cord tissue samples was monitored by using a chemiluminescence (CL) technique.

Results:

SCI caused a significant decrease in spinal cord GSH content, which was accompanied with significant increases in luminol CL and MDA levels, MPO activity, and DNA damage. Furthermore, LA treatment reversed all these biochemical parameters as well as SCI-induced histopathologic alterations. Conversely, impairment of the neurologic function caused by SCI remained unchanged.

Conclusion:

The present study suggests that LA reduces SCI-induced oxidative stress and exerts neuroprotection by inhibiting lipid peroxidation, glutathione depletion, and DNA fragmentation.  相似文献   
83.
OBJECTIVE: The aim of this study is to investigate dose-dependent effect of the topical application of methotrexate (MTX) in rats on the normal nasal mucosa, liver tissue, liver enzymes, and hemoglobin levels. STUDY DESIGN: Preclinical animal study. SETTING: Twenty male adult wistar albino rats were randomly divided into 4 groups (n=5). A single puff of MTX (2.5 microg) was applied to both nasal cavities 2 times a day. The animals were given MTX 1 day a week in group 1, 3 days a week in group 2, and 5 days a week in group 3. Control group animals were given 1 puff of physiologic saline to both nasal cavities 5 days a week and 2 times a day. After 28 days, liver biopsies, blood samples, and 5 nasal mucosal biopsies were taken. Histological examination was made with respect to certain parameters semiquantitatively (grade 0-3). The aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and hemoglobin counts were studied from blood samples. RESULTS: There are no statistically significant differences with respect to histopathological parameters between the control group and the groups 1-3 (P>0.05). Histopathological examination of liver tissue did not reveal any evident difference between the control and study groups. Mean AST and ALT as liver function tests and hemoglobin counts were within normal limits. Topical application of MTX at these doses has no toxic effect on the nasal mucosa, the liver tissue, AST and ALT levels, and hemoglobin level. CONCLUSIONS: These results have been encouraging to investigate use of the topical application of MTX in nasal manifestation of autoimmune disease or addition of the topical application of MTX to the steroid treatment in cases with massive nasal polyposis resistant to steroids and prone to recurrence.  相似文献   
84.
A severe form of Volkmann contracture is associated with loss of flexor and extensor compartment muscles. An 11-year-old boy with Volkmann contracture was admitted to our clinics with flexion contracture of the wrist joint and total loss of flexor and extensor muscle functions. Split latissimus dorsi free flap was used for reconstruction. The muscle was split based on the branching of thoracodorsal nerve and artery within the muscle so that each part of the muscle is nourished and innervated by a branch of thoracodorsal nerve and artery. No complication has occurred, and the patient can now grasp objects, although he cannot achieve full range of motion of the fingers. We performed a single muscle transfer for reconstruction of both the extensor and flexor compartments in severe form of Volkmann contracture and omitted the use of a second muscle transfer, thus greatly decreasing the operative time, cost, and morbidity.  相似文献   
85.
Torticollis is either congenital or acquired in childhood. Acquired torticollis is not a diagnosis but rather a sign of an underlying disorder. The causes of acquired torticollis include ligamentous, muscular, osseous, ocular, psychiatric, and neurologic disorders and may be a symptom of significant abnormalities of the spinal cord and brain, such as spinal syrinx or central nervous system neoplasia. Torticollis is rarely considered to be an initial clinical presentation of posterior fossa and cervical spinal cord tumors. We report five cases of pediatric tumors with torticollis at the onset: an astrocytoma originating from the medulla oblongata, another presumptive astrocytoma of the spinal cord located between C1 and C6 cervical vertebrae (not operated), an ependymoma located throughout the whole cervical spinal cord extending into the bulbomedullary junction, an astrocytoma originating from the bulbus and extending into the posterior fossa, and another case of a eosinophilic granuloma located extradurally through the anterior and posterior portions of the vertebral bodies from C3 to C7 producing the collapse of the sixth cervical vertebra. All five cases were seen in children, aged between 3 and 12 years. All these cases reflect the misinterpretation of this neurological sign and the lack of association with the possibility of spinal or posterior fossa tumor. This delay in the diagnosis of these diseases led to progressive neurological deterioration and to the increase in the tumor size, which made surgical intervention difficult and the prognosis unfavorable. Although torticollis secondary to tumors is rarely seen, it is necessary to be kept in mind in the differential diagnosis.  相似文献   
86.
It is controversial to perform bone surgery at the time of open reduction in developmental dislocation of the hip in children 12-18 months old. The purpose of this study is to investigate whether concomitant bone surgery is necessary in patients treated with medial open reduction in this age range. Patients that were under 12 months of age at the time of open reduction were compared with patients that were 12-18 months old. Forty-four hips of 30 patients treated with open reduction through Ferguson's medial approach have been included in the study. Mean follow-up was 19.6 years (13-27.5). Age at the time of open reduction was less than 12 months in 21 hips (group A) and 12 months or more in 23 hips (group B). There was no significant difference between two groups concerning avascular necrosis or unsatisfactory radiological outcome (Severin's groups III and IV). A higher rate of secondary bone surgery was necessary in group B than in group A. Although secondary bone surgery is needed at a higher frequency in children 12-18 months old, the radiological outcome is not significantly different for patients younger than 12 months. Therefore, the recommendation of concomitant bone surgery on a routine basis during open reduction in developmental dislocation of the hip in children 12-18 months old is debatable.  相似文献   
87.
88.
89.
Thrombotic microangiopathies (TMAs) are rare, but life-threatening disorders characterized by microangiopathic hemolytic anemia and thrombocytopenia (MAHAT) associated with multiorgan dysfunction as a result of microvascular thrombosis and tissue ischemia. The differentiation of the etiology is of utmost importance as the pathophysiological basis will dictate the choice of appropriate treatment.We retrospectively evaluated 154 (99 females and 55 males) patients who received therapeutic plasma exchange (TPE) due to a presumptive diagnosis of TMA, who had serum ADAMTS13 activity/anti-ADAMTS13 antibody analysis at the time of hospital admission. The median age of the study cohort was 36 (14-84). 67 (43.5%), 32 (20.8%), 27 (17.5%) and 28 (18.2%) patients were diagnosed as thrombotic thrombocytopenic purpura (TTP), infection/complement-associated hemolytic uremic syndrome (IA/CA-HUS), secondary TMA and TMA-not otherwise specified (TMA-NOS), respectively. Patients received a median of 18 (1­75) plasma volume exchanges for 14 (153) days. 81 (52.6%) patients received concomitant steroid therapy with TPE. Treatment responses could be evaluated in 137 patients. 90 patients (65.7%) achieved clinical remission following TPE, while 47 (34.3%) patients had non-responsive disease. 25 (18.2%) non-responsive patients died during follow-up. Our study present real-life data on the distribution and follow-up of patients with TMAs who were referred to therapeutic apheresis centers for the application of TPE.  相似文献   
90.
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