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91.
Undifferentiated mouse embryonic stem cells (ESCs) possess low numbers of mitochondrial DNA (mtDNA), which encodes key subunits associated with the generation of ATP through oxidative phosphorylation (OXPHOS). As ESCs differentiate, mtDNA copy number is regulated by the nuclear-encoded mtDNA replication factors, which initiate a major replication event on Day 6 of differentiation. Here, we examined mtDNA replication events in somatic cells reprogrammed to pluripotency, namely somatic cell-ES (SC-ES), somatic cell nuclear transfer ES (NT-ES) and induced pluripotent stem (iPS) cells, all at low-passage. MtDNA copy number in undifferentiated iPS cells was similar to ESCs whilst SC-ES and NT-ES cells had significantly increased levels, which correlated positively and negatively with Nanog and Sox2 expression, respectively. During pluripotency and differentiation, the expression of the mtDNA-specific replication factors, PolgA and Peo1, were differentially expressed in iPS and SC-ES cells when compared to ESCs. Throughout differentiation, reprogrammed somatic cells were unable to accumulate mtDNA copy number, characteristic of ESCs, especially on Day 6. In addition, iPS and SC-ES cells were also unable to regulate ATP content in a manner similar to differentiating ESCs prior to Day 14. The treatment of reprogrammed somatic cells with an inhibitor of de novo DNA methylation, 5-Azacytidine, prior to differentiation enabled iPS cells, but not SC-ES and NT-ES cells, to accumulate mtDNA copies per cell in a manner similar to ESCs. These data demonstrate that the reprogramming process disrupts the regulation of mtDNA replication during pluripotency but this can be re-established through the use of epigenetic modifiers.  相似文献   
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Background: It is suggested that there may be expanded use of surfactant replacement for the neonatal diseases such as meconium aspiration syndrome (MAS), pneumonia and possibly bronchopulmonary dysplasia (BPD).

Objective: To evaluate the characteristics and short-term outcome of the neonates given exogenous surfactant because of the diseases other than respiratory disease syndrome (RDS).

Methods: This retrospective study included 35 neonates admitted to the neonatal intensive care unit from January 2012 to December 2012 for an expanded use of surfactant. Data related to gestational age, birth weight, gender and perinatal risk factors were obtained from the patients’ records. The short-term prognosis was also noted.

Results: The diagnosis was sepsis in 16 patients, eight MAS, seven transient tachypnea of the newborns (TTN) and four BPD. Mean gestational age was 35.6?±?4.5 weeks and mean birth weight was 2661?±?981?g. Of overall cases, 65% were boys and 35% girls. The mortality rate was 17%. Of six fatal cases, three was with BPD, two with sepsis and one with MAS.

Conclusion: We think that surfactant replacement may be life saver in the neonatal diseases other than RDS such as BPD, MAS and sepsis by rapidly improving oxygenation. Further investigation is necessary to validate the significance of expanded use of surfactant.  相似文献   
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Purpose

Percutaneous nephrostomy (PCN) in a nondilated pelvicaliceal system is technically challenging. We describe an effective method to achieve transient dilatation of the pelvicaliceal system via induction of diuresis using infusion of a diuretic agent in normal saline, therefore allowing easier access to the pelvicaliceal system.

Methods

Under real-time ultrasound guidance, the technique had been tested in 22 nephrostomies with nondilated system (a total of 20 patients with 2 patients having bilateral nephrostomies) during a 5-year period. Patients were given 40 mg of furosemide in 250 ml of normal saline solution intravenously by rapid infusion. As soon as maximum calyceal dilatation of more than 5 mm was observed, which is usually 15 min later after the end of rapid infusion, patients were positioned obliquely, and PCN procedure under ultrasound guidance was performed.

Results

The procedure was successful in 19 of the nephrostomies in 17 patients with a success rate of 86.36 % per procedure and 85 % per patient in nondilated pelvicaliceal systems. No major nephrostomy-, drug-, or technique-related complications were encountered. The technique failed to work in three patients due to the presence of double J catheters and preexisting calyceal perforation which avoided transient dilation of the pelvicaliceal system with diuresis.

Conclusions

Diuretic infusion in saline is a feasible and effective method for PCN in nondilated pelvicaliceal systems.  相似文献   
96.
Crisponi syndrome is a recently described rare autosomal recessive disorder. The main clinical features of the syndrome are neonatal onset of episodic contractions of the facial muscles with trismus and abundant salivation resembling a tetanic spasm. Herein, we report a case of 3-day-old male neonate presenting with trismus, abundant salivation, feeding difficulties, camptodactyly, and hyperthermia, which are consistent with the diagnostic criteria of Crisponi syndrome. The parents of the patient were consanguineous, supporting autosomal recessive inheritance. Molecular analysis revealed a homozygous mutation in cytokine receptor-like factor-1 gene in the patient.  相似文献   
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Background  

Neurological patients have lower mortality and better outcomes when cared for in specialized neurointensive care units than in general ICUs. However, little is known about how the process of care differs between these types of units.  相似文献   
99.
The purpose of this study is to report the outcomes of patients with locally advanced (T3-T4) oral cancers undergoing surgical resection and free tissue reconstruction without the lower lip-split procedure. In this retrospective chart review, we analyzed 86 consecutive patients presenting between July 2000 and December 2009 at our university-based, tertiary care medical center. The oral site distribution was: 73 (86%) oral cavity, 10 (12%) oropharynx, and 3 (2%) combined. The average specimen volume was 240.3 cm(3) (range 17.5-3718 cm(3)). Sixty-seven patients (78%) had widely clear histopathologic margins. Performing mandibulectomy had no advantage over maintaining mandible continuity to achieve clear margins (P = 0.97). Nineteen patients (22%) had focally involved microscopic margins; 10 (53%) soft tissue, seven (37%) bone, and two (10%) both. Thirty patients (35%) had postoperative complications, and 16 patients (19%) had a salivary fistula. The flaps used were: 39 fibula (45%), 25 radial forearm (29%), eight anterolateral thigh (9%), eight rectus abdominus (9%), three scapula (4%), and three iliac crest (4%). The average length of bone used was 9 cm (range 5-16 cm). The average soft tissue area was 99.7 cm(2) (range 24-300 cm(2)). Nine patients (10%) had either partial or total flap loss. The lower lip-split procedure for surgical exposure is unnecessary for both oncologic resection and reconstruction for locally advanced oral cancers. Clear margins, relatively facile flap inset with high success rates, and acceptable complication rates can be safely achieved in this patient population.  相似文献   
100.
Tuberculosis (TB) is no longer a disease limited to developing nations and is still a major cause of significant morbidity and mortality worldwide. The indolent clinical presentation, emergence of multidrug-resistant mycobacteria, and association with human immunodeficiency virus infection poses obstacles for early diagnosis and management. Compared with the other forms of TB, musculoskeletal involvement is relatively rare. Tuberculous spondylitis is the most common form of musculoskeletal TB and accounts for ~50% of cases. Extraspinal musculoskeletal TB shows a predilection for large weightbearing joints, long bones, and the skull. This article reviews the radiologic features of diverse forms of osseous TB and the diagnostic value of the different imaging techniques. It also reviews the imaging differential diagnoses, including other infections and malignancies/metastases. Conventional radiography is of key value in the diagnosis of musculoskeletal TB. Computed tomography, magnetic resonance imaging, and bone scintigraphy also play key roles in the early detection of disease and in demonstrating the extent of disease process and soft tissue involvement. Because delay in treatment significantly reduces the cure rate and increases the rate of complications and morbidity, early radiological diagnosis of TB is of paramount importance for appropriate management.  相似文献   
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