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1.
ObjectiveTo compare image quality of free-breathing T2-weighted MultiVane-XD (MVXD) sequence (non-Cartesian k-space filling using radial rectangular blades) with conventional MR sequences (short tau inversion recovery [STIR],balanced true field echo [BTFE], T1 in phase fast field echo [T1 FFE], and T1-fat saturated postgadolinium [T1PG]) in MR imaging of chest.Materials and MethodsTwenty-one patients (10 men and 11 women) underwent chest MRI including T2W MVXD, STIR, BTFE (18/21), T1 FFE, T1PG (10/21) sequences at 1.5 T. Two reviewers (A.S.B and M.J. with 20 and 10 years of experience in pulmonary imaging, respectively) evaluated each sequence with respect to overall image quality, image sharpness, definition of mediastinal vessels including the aorta, pulmonary arteries, superior vena cava, intrapulmonary vessels; trachea, main bronchi, intrapulmonary airways; lung-mediastinal interface, pulmonary lesion detection, and artefacts in the upper, middle, and lower third of chest using 5-point scales. No sedation was given. Pairwise comparisons between T2W MVXD and the 4 conventional sequences were made using unpaired student's t test.ResultsMean age of patients was 30.67 years (range: 6-60 years). T2 MVXD showed significantly better overall image quality and sharpness than STIR, T1 FFE, and T1PG (P < 0.01) while it was comparable to BTFE. Mediastinal vessels were significantly better visualized on T2 MVXD as compared to STIR and T1 (P < 0.003). However, BTFE and T1PG were superior to T2 MVXD for visualization of great vessels, SVC, and intrapulmonary vessels (P < 0.01). Visualization of trachea, major bronchi, intrapulmonary airways as well as intrapulmonary lesion detection was significantly better on T2 MVXD images in comparison to any of the other 4 sequences (P < 0.03). Intrapulmonary artifacts were significantly lesser in BTFE images as compared to T2 MVXD (P < 0.01). No significant difference was found between the severity of intrapulmonary artifacts in other MR sequences as compared to T2 MVXD.ConclusionsBy virtue of its better overall image quality, sharpness, superior visualization of mediastinal airways, and lesion detection, T2 MultiVane-XD promises to be a robust addition in the armamentarium of thoracic radiologists.  相似文献   
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The neural crest serves as a powerful and tractable model paradigm for understanding collective cell migration. The neural crest cell populations are well-known for their long-distance collective migration and contribution to diverse cell lineages during vertebrate development. If neural crest cells fail to reach a target or populate an incorrect location, then improper cell differentiation or uncontrolled cell proliferation can result. A wide range of interdisciplinary studies has been carried out to understand the response of neural crest cells to different stimuli and their ability to migrate to distant targets. In this critical commentary, we illustrate how an interdisciplinary collaboration involving experimental and mathematical modeling has led to a deeper understanding of cranial neural crest cell migration. We identify open questions and propose possible ways to start answering some of the challenges arising.  相似文献   
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PURPOSE: The purpose of this study was to evaluate the efficacy of modified medial canthal tendon plication technique for correcting laxity of the medial end of the lower eyelid. MATERIAL AND METHODS: Eleven patients (9 males and 2 females, 21 eyes), with an age range of 31-80 years, having laxity of the medial end of the lower lid of varying degrees were enrolled in this study. These patients presented with complaints of watering, recurrent redness, photophobia and foreign body sensation. After grading the amount of lower lid laxity, plication was performed. In patients in whom laxity was associated with ectropion, the severity of lower lid ectropion was also graded. In patients with ectropion of Grade II or more, additional procedures for its correction were performed before undertaking plication. The patients were followed up 6 months post-operatively and re-assessed for laxity, recurrence of symptoms and complications of plication. RESULTS: All the lids were evaluated for the amount and extent of laxity of lower lid. Twelve (57%) eyes had Grade I, 9 (43%) had Grade II (and none Grade III) laxity of the lower lid. Twelve eyes had laxity restricted to the medial end and 9 eyes had laxity of the entire length of the lower lid. Some eyes also had an associated ectropion. Among the 21 eyes, 4 eyes (22%) had Grade 1, 11 (61%) had Grade 2, 6 (17%) Grade 3 and none Grade 4 ectropion. In the lids with associated ectropion, additional procedures had been performed. In 1 eye, the medial canthus was anchored to the tendon and this patient had poor apposition of the lower lid to the globe. Hence, in the remaining 20 eyes, the medial canthus was anchored to the orbital periosteum. The mean change in eyelid length was 2.6 mm (measured from medial to lateral canthus) from pre-operative status (33+/-3.4 mm) to the post-operative status (30+/-2.9 mm) this being statistically significant. An overriding of the lower lid was seen in 2 eyes (10%), and a residual gap between the lower lid and globe was noticed in 15 (71%) eyes. Some eyes had uncorrected symptoms including epiphora (3 eyes; 14%), redness (2 eyes; 10%), and photophobia (1 eye; 5%). All were those in which the lateral end was lax. None had a recurrence of foreign body sensation. CONCLUSION: Plication is easy, effective and quick for correcting laxity of the lower lid when restricted predominantly to the medial end. Correct identification of anatomical landmarks and appropriate tension of sutures is vital to achieve proper apposition of the lower lid to the globe.  相似文献   
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PURPOSE: To report a patient with transient recurrence of lacrimal pressure regurgitation following a successful conventional external dacryocystorhinostomy. MATERIAL AND METHODS: A 22-year-old female, who had undergone conventional external dacryocystorhinostomy, presented 3 days later with a recurrence of pressure regurgitation. The patient's symptoms disappeared spontaneously 7 days later. Serial naso-endoscopic examination was used to find the cause. RESULTS: Endoscopic examination showed an oedematous posterior nasal mucosal remnant obstructing the lacrimal drainage pathway. On account of its peculiar location, shape and movements, and the surgically induced tissue oedema, this mucosal remnant misdirected the fluid coming through the canalicular system away from the nasal cavity into the lacrimal pocket. Ten days later, due to healing fibrosis, this flap adhered permanently to the lateral nasal wall and the patient's symptoms disappeared spontaneously. CONCLUSION: Nasal endoscopy is a simple, quick and convenient technique for diagnosing the cause of obstruction in the lacrimal drainage system. The surgeon should aim for large anterior lacrimal and anterior nasal mucosal flaps, and every remnant of posterior flaps should be excised during dacryocystorhinostomy.  相似文献   
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Background:

The most common definitions of large volume liposuction refer to total 5 l volume aspiration during a single procedure (fat plus wetting solution). Profound haemodynamic and metabolic alterations can accompany large volume liposuction. Due to paucity of literature on the effect of different tumescent solutions on the electrolyte balance and haematological changes during large volume liposuction, we carried out this study using two different wetting solutions to study the same.

Materials and Methods:

Total 30 patients presenting with varying degrees of localized lipodystrophy in different body regions were enrolled for the study. Prospective randomized controlled trial was conducted by Department of Plastic and Cosmetic Surgery, Sir Ganga Ram Hospital, New Delhi from January 2011 to June 2012. Patients were randomized into two groups of 15 patients each by using computer generated random numbers. Tumescent formula used for Group A (normal saline [NS]) was our modification of Klein''s Formula and Tumescent formula used for Group B (ringer lactate [RL]) was our modification of Hunstadt''s formula. Serum electrolytes and hematocrit levels were done at preinduction, immediate postoperative period and postoperative day 1.

Result:

Statistical analysis was performed using SPSS software version 15.0. Which showed statistically significant electrolytes and hematocrit changes occur during large volume liposuction.

Conclusion:

Statistically significant electrolytes and hematocrit changes occur during large volume liposuction and patients should be kept under observation of anaesthesist for at least 24 h. Patients require strict monitoring of vital parameters and usually Intensive Care Unit is not required. There was no statistical difference in the electrolyte changes using NS or RL as tumescent solution and both solutions were found safe for large volume liposuction.KEY WORDS: Electrolyte changes during liposuction, haemogram changes during liposuction, large volume liposuction  相似文献   
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Background

Acetabulum has a complex anatomy due to which anatomical acetabular plates are still under developmental phase. Although intra-operative contouring of reconstruction plate is done as a standard practice, it is associated with increased operative time and morbidity of patient. We have designed an acetabular plate for posterior fixation from experience of previous studies performed in our institute on acetabular fracture fixation which should be appropriate for most of the patient of Indian origin. Apart from avoiding intra-operative contouring of acetabular plates it also helps in preventing intra articular screw penetration.

Methods

We selected five consecutive patients with acetabular fracture needed to be operated from posterior approach and designed patient specific plate template from virtual surgical planning and 3D printing. These plate templates were then matched with our acetabular plate design and were used intra-operatively. Many parameters were assessed to evaluate accuracy of our plate design in those five patients.

Result

All the plate templates appear to match our designed plate and no intra-operative contouring was required with our plate design.

Conclusion

This was a pilot study and we need a large sample size to study accuracy of our acetabular plate design which might avoid intra-operative contouring, decreasing morbidity of patient and prevent wastage of resources in pre-operative planning and computer designing.  相似文献   
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Subacute posttraumatic ascending myelopathy is a rare disorder, unrelated to syrinx formation or mechanical instability, which may gradually emerge within the first 1-2 weeks after a spinal cord injury and may lead to diagnostic and prognostic dilemmas. We present a case of 24-year-old female with unstable wedge compression fracture of L1 vertebrae with signal changes in the upper lumbar cord causing complete paraplegia below D9 with bladder and bowel involvement. In the subsequent week, she developed a delayed progressively increasing neurological deficit with cord signal abnormality on MRI extending cephalad from the injury site to the upper dorsal cord. The patient had no initial clinical improvement initially but showed a delayed recovery over months.  相似文献   
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