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61.
The purpose of this study was to analyze the expression of B cell growth factor (BCGF) receptors and to elucidate the biologic effects of biochemically purified natural BCGF at the B cell precursor stage of human B lineage lymphoid differentiation. The specific binding of radioiodinated high-mol-wt BCGF (125I-HMW-BCGF) and low-molecular-wt BCGF (125I-LMW-BCGF) to fresh marrow blasts from B cell precursor acute lymphoblastic leukemia (ALL) patients was initially investigated. The estimated number of radioiodinated BCGF molecules bound per blast ranged from undetectable to 24.3 X 10(3) for HMW-BCGF, and from 11.5 X 10(3) to 457.8 X 10(3) for LMW-BCGF. In 3H-TdR incorporation assays, 75% of cases showed a significant response to LMW-BCGF with a median stimulation index of 9.3. By comparison, only 33% of cases showed a significant response to HMW-BCGF with a median stimulation index of 2.4. Subsequently, B cell precursor colony assays were performed to assess and compare the biologic effects of BCGF on leukemic B lineage lymphoid progenitor cells. Among 28 cases studied, 57% responded to both HMW-BCGF and LMW-BCGF, 21% responded only to LMW-BCGF, and the remaining cases showed no proliferative response to either growth factor. The response patterns of virtually pure populations of FACS- sorted leukemic B cell precursors were essentially identical to the proliferative responses of unsorted leukemic B-cell precursors. Synergistic effects between HMW-BCGF and LMW-BCGF were observed in 80% of the cases that responded to both. The numbers of cell-bound radioiodinated BCGF molecules, the stimulation indices, as well as the number of B cell precursor colonies in BCGF-stimulated cultures showed a marked interpatient variation. Patients with structural chromosomal abnormalities (SCAs) involving 12p11-13 or patients with a Philadelphia chromosome showed a greater HMW-BCGF response at the level of leukemic progenitor cells than did other patients (P = .02). The LMW-BCGF response was significantly greater for patients with SCA than for patients without SCA (P = .04). The response of leukemic progenitor cells to HMW-BCGF or LMW-BCGF did not correlate with sex, age, disease status, FAB morphology, WBC at diagnosis, or immunophenotype. To our knowledge, this study represents the first detailed analyses of BCGF receptor expression and BCGF effects in B cell precursor ALL. The data presented provide direct evidence for the expression of functional receptors for both HMW-BCGF and LMW-BCGF in B cell precursor ALL.  相似文献   
62.
AIM: To assess role of combined modality of mechanical fragmentation and intralesional thrombolysis in patients with massive pulmonary embolism presenting subacutely. METHODS: Eight of 70 patients presenting in tertiary care centre of North India with massive pulmonary embolism within 4 years had subacute presentation (symptom onset more than 2 wk). These patients were subjected to pulmonary angiography with intention to treat basis via mechanical breakdown and intra lesional thrombolysis. Mechanical breakdown of embolus was accomplished with 5-F multipurpose catheter to reestablish flow, followed by intralesional infusion of urokinase (4400 IU/kg over 10 min followed by 4400 IU/kg per hour over 24 h). RESULTS: Eight patients, mean age 47.77±12.20 years presented with subacute pulmonary embolism (mean duration of symptoms 2.4 wk). At presentation, mean heart rate, shock index, miller score and mean pulmonary pressures were 101.5±15.2/min, 0.995±0.156, 23.87±3.76 and 37.62±6.67 mmHg which reduced to 91.5±12.2/min (P=0.0325), 0.789±0.139 (P=0.0019), 5.87±1.73 (P=0.0000004) and 27.75±8.66 mmHg (P=0.0003) post procedurally. Mean BP improved from 80.00±3.09 mmHg to 90.58±9.13 mmHg (P=0.0100) post procedurally. Minor complications in the form of local hematoma-minor hematoma in 1 (12.5%), and pseudoaneurysm (due to femoral artery puncture) in 1 (12.5 %) patient were seen. At 30 d and 6 mo follow up survival rate was 100% and all the patients were asymptomatic and in New York Heart Association class 1. CONCLUSION: Combined modality of mechanical fragmentation and intralesional thrombolysis appears to be a promising alternative to high risk surgical procedures in patients with subacute massive pulmonary embolism.  相似文献   
63.
Post-catheterization PSA is one of the most commonly encountered vascular complications of cardiac and peripheral angiographic procedures. We report the case of patient who developed deep-seated profunda femoris artery pseudoaneurysm (PSA) following cardiac catheterization. Despite, repeated ultrasound guided compressions the PSA failed to close and instead produced local site pressure ulcers. The secondary infection followed which precluded use of percutaneous thrombin injection. The PSA was finally closed via a total endovascular technique combining intravascular thrombin injection and coil embolization, thus obviating the need for expensive measures like cover stents or invasive surgical repairs.  相似文献   
64.
Subramaniam P  Behari S  Singh S  Jain VK  Chhabra DK 《Surgical neurology》2002,58(5):338-43; discussion 343
BACKGROUND: Intradural subpial lipomas not associated with spinal dysraphism, account for less than 1% of spinal cord tumors. The simultaneous existence of multiple intradural subpial lipomas with dumb-bell extradural extension through the intervertebral foramen in the same patient without any evidence of spinal dysraphism has not been previously reported. CASE DESCRIPTION: A 38-year-old man presented with progressive spastic paraparesis, and weakness of right elbow extension and opposition of the medial three fingers. He also had ascending paraesthesia from the C6 dermatome to the saddle region and loss of joint and position sense of both lower limbs with hesitancy and precipitancy of micturition. There was no spinal tenderness, deformity, neurocutaneous markers, or spinal dysraphism. The total duration of illness was 11 years.The oblique views of the plain radiographs of the cervical spine revealed an enlarged right C7-D1 intervertebral foramen. The T1- and T2-weighted magnetic resonance (MR) images showed two intradural, hyperintense lesions (with extensive loss of signal on fat suppression sequences), one extending from C5 to D2 and the other opposite the C3-4 disc space. The parasagittal and axial images showed the extradural component of the lesion emerging from the right C7-D1 intervertebral foramen.At surgery, a C2 to D2 laminectomy was performed. The lipoma, enclosed in a fine pial membrane, was situated on the right posterolateral aspect of the cord. The right-sided nerve roots from the C6 to D1 levels were completely enmeshed by the lipoma. There was a separate superficial subpial lipoma adherent to the posterior aspect of the cord at the C3-4 level. A distinct area of normal cord was present between the two lesions. A subtotal decompression of the lesions including the component emerging through the right C7-D1 intervertebral foramen and a duraplasty were performed.At follow-up after 18 months, the posterior column impairment, lower limb hypoaesthesia, and right upper limb paraesthesia had improved. However, residual elbow extension and lower limb weakness, mild lower limb spasticity and sphincteric dysfunction persisted. CONCLUSIONS: The multiplicity of intradural subpial lipomas without spinal dysraphism points to a dysembryogenetic basis similar to that seen in patients with spinal dysraphism that results in lipomas, but in which the defect is not severe enough to give rise to coexisting vertebral and soft tissue anomalies. The dumb-bell extradural extension through the intervertebral foramen is extremely rare. The magnetic resonance imaging and surgical principles are discussed.  相似文献   
65.
We report a rare case of high cervical intramedullary ependymal cyst in a young boy. This was associated with atlantoaxial dislocation. After partial removal and marsupialization, the cyst recurred and needed radical total resection.  相似文献   
66.
Although renal abnormalities have been described in children with Alagille's syndrome, cystic kidney disease has not often been documented, and then usually only at necropsy. Three children with Alagille's syndrome are described, in two of whom a unilateral multicystic dysplastic kidney was detected by prenatal ultrasound; in the other, a solitary cortical cyst was found later in childhood. All have normal renal function, growth, and liver synthetic function but continue to have clinical and biochemical signs of cholestasis. These cases show that unilateral cystic kidney disease with or without renal dysplasia may be associated with Alagille's syndrome, that the clinical course is not necessarily unfavourable, and that Alagille's syndrome should be included in the differential diagnosis of cystic kidney disorders associated with cholestatic liver disease. Patients with Alagille's syndrome should be evaluated by renal ultrasound.  相似文献   
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