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11.

Background  

Low cardiac output (LCO) after corrective surgery remains a serious complication in pediatric congenital heart diseases (CHD). In the case of refractory LCO, extra corporeal life support (ECLS) extra corporeal membrane oxygenation (ECMO) or ventricle assist devices (VAD) is the final therapeutic option. In the present study we have reviewed the outcomes of pediatric patients after corrective surgery necessitating ECLS and compared outcomes with pediatric patients necessitating ECLS because of dilatated cardiomyopathy (DCM).  相似文献   
12.
McGuire KJ  Chacko AT  Bernstein J 《Orthopedics》2011,34(10):e598-e601
Hospitals with lower costs are not necessarily superior to those that are more expensive, because the more costly institutions might offer better outcomes. The purpose of this study was to consider prices and outcomes in an integrated model and thereby determine if teaching hospitals are cost-effective for the care of hip fractures. We analyzed the claims data of a sample of 18,908 Medicare patients who were admitted to one of 190 acute care hospitals for surgical treatment of a hip fracture. For each hospital, we assessed the relationship between the total per capita Medicare payments over a 6-month period following admission and the 30-day and 6-month mortality. The data were analyzed as a function of hospital type: teaching vs nonteaching. The mean adjusted costs were $5910 per patient higher at teaching hospitals compared to nonteaching hospitals (approximately $24,000 vs $18,000) However, the adjusted 6-month mortality was 1.4% lower at major teaching hospitals. The adjusted incremental cost-effectiveness for teaching hospitals was $422,143 per life saved. By that measure, each life saved would have to yield nearly 8.5 additional quality-adjusted life years (QALY) to attain the $50,000/QALY standard thought to represent cost-effective spending, an unlikely target given the age of the typical hip fracture patient. Nonetheless, because teaching hospitals are more expensive than non-teaching hospitals, a relatively small cut in the overall cost of care at teaching hospitals could dramatically decrease the marginal cost of each life saved. The elements of teaching hospital care that improve survival might be identified in further studies and instituted, perhaps, at non-teaching hospitals without greatly increasing their cost structure.  相似文献   
13.
This article presents improvement on a physical cardiovascular simulator (PCS) system. Intraventricular pressure versus intraventricular volume (PxV) loop was obtained to evaluate performance of a pulsatile chamber mimicking the human left ventricle. PxV loop shows heart contractility and is normally used to evaluate heart performance. In many heart diseases, the stroke volume decreases because of low heart contractility. This pathological situation must be simulated by the PCS in order to evaluate the assistance provided by a ventricular assist device (VAD). The PCS system is automatically controlled by a computer and is an auxiliary tool for VAD control strategies development. This PCS system is according to a Windkessel model where lumped parameters are used for cardiovascular system analysis. Peripheral resistance, arteries compliance, and fluid inertance are simulated. The simulator has an actuator with a roller screw and brushless direct current motor, and the stroke volume is regulated by the actuator displacement. Internal pressure and volume measurements are monitored to obtain the PxV loop. Left chamber internal pressure is directly obtained by pressure transducer; however, internal volume has been obtained indirectly by using a linear variable differential transformer, which senses the diaphragm displacement. Correlations between the internal volume and diaphragm position are made. LabVIEW integrates these signals and shows the pressure versus internal volume loop. The results that have been obtained from the PCS system show PxV loops at different ventricle elastances, making possible the simulation of pathological situations. A preliminary test with a pulsatile VAD attached to PCS system was made.  相似文献   
14.
Abstract:  This work presents results of preliminary studies concerning application of magnetic bearing in a ventricular assist device (VAD) being developed by Dante Pazzanese Institute of Cardiology—IDPC (São Paulo, Brazil). The VAD-IDPC has a novel architecture that distinguishes from other known VADs. In this, the rotor has a conical geometry with spiral impellers, showing characteristics that are intermediate between a centrifugal VAD and an axial VAD. The effectiveness of this new type of blood pumping principle was showed by tests and by using it in heart surgery for external blood circulation. However, the developed VAD uses a combination of ball bearings and mechanical seals, limiting the life for some 10 h, making impossible its long-term use or its use as an implantable VAD. As a part of development of an implantable VAD, this work aims at the replacement of ball bearings by a magnetic bearing. The most important magnetic bearing principles are studied and the magnetic bearing developed by Escola Politécnica of São Paulo University (EPUSP-MB) is elected because of its very simple architecture. Besides presenting the principle of the EPUSP-MB, this work presents one possible alternative for applying the EPUSP-MB in the IDPC-VAD.  相似文献   
15.
16.
Literature shows that HER2/neu positive breast cancer cells are more sensitive to radiation-induced apoptosis by targeting the epidermal growth factor receptor family tyrosine kinase. We selected 466 patients with pT1-2 HER2/neu positive tumors who received adjuvant trastuzumab for primary invasive breast cancer. Patients were divided into three groups [Quadrantectomy followed by conventional radiotherapy vs Quadrantectomy followed by Intra-operative radiotherapy with electrons vs Mastectomy without radiotherapy]. After a median follow-up of 52 months, the 5-year cumulative incidence of locoregional recurrence (LRR) was 1.9%, 11.5% and 5.0% respectively (p < 0.01). At the multivariate analysis, extensive perivascular invasion, Luminal B HER2/Progesterone Receptor (PgR) negative status and Quadrantectomy followed by Intra-operative radiotherapy with electrons have significantly increased the risk of LRR. Our results suggest that HER2/neu positive breast cancer might have better outcomes when treated simultaneously with external radiotherapy and trastuzumab. Moreover, we underline the importance of PgR and further new stratification of risk among luminal subtypes.  相似文献   
17.
Introduction: Clinical results of radical cystectomy performed on elderly bladder cancer patients over 70 years old were assessed to determine whether age is one of the critical points for the application of this type of surgery. Materials: From January 1992 to December 2002, 41 radical cystectomy performed in septuagenarian population were compared with 197 performed in patients less than 70 years of age. Results: The early and late complication rate for septuagenarians was 29.7% and 12%, compared with 26.9% and 9.6% for patients younger than 70 years respectively. The overall mortality rate for septuagenarians was 4.9%, compared with 8.6% for patients younger than 70 years. There was no significant difference between the two groups with regard to pathologic stage or length of hospital stay. The 5-year overall survival rate for septuagenarians was 53% compared with 59% for patients younger than 70 years. Conclusions: When indicated after adequate preoperative assessment and optimization of the patient, radical cystectomy is a safe procedure in the septuagenarians and patient should not be denied surgery dependent on chronologic age.  相似文献   
18.

Background

Robot-assisted and laparoscopic partial nephrectomies (PNs) for medial tumors are technically challenging even with the hilum clamped and, until now, were impossible to perform with the hilum unclamped.

Objective

Evaluate whether targeted vascular microdissection (VMD) of renal artery branches allows zero-ischemia PN to be performed even for challenging medial tumors.

Design, setting, and participants

A prospective cohort evaluation of 44 patients with renal masses who underwent robot-assisted or laparoscopic zero-ischemia PN either with anatomic VMD (group 1; n = 22) or without anatomic VMD (group 2; n = 22) performed by a single surgeon from April 2010 to January 2011.

Intervention

Zero-ischemia PN with VMD incorporates four maneuvers: (1) preoperative computed tomographic reconstruction of renal arterial branch anatomy, (2) anatomic dissection of targeted, tumor-specific tertiary or higher-order renal arterial branches, (3) neurosurgical aneurysm microsurgical bulldog clamp(s) for superselective tumor devascularization, and (4) transient, controlled reduction of blood pressure, if necessary.

Measurements

Baseline, perioperative, and postoperative data were collected prospectively.

Results and limitations

Group 1 tumors were larger (4.3 vs 2.6 cm; p = 0.011), were more often hilar (41% vs 9%; p = 0.09), were medial (59% and 23%; p = 0.017), were closer to the hilum (1.46 vs 3.26 cm; p = 0.0002), and had a lower C index score (2.1 vs 3.9; p = 0.004) and higher RENAL nephrometry scores (7.7 vs 6.2; p = 0.013). Despite greater complexity, no group 1 tumor required hilar clamping, and perioperative outcomes were similar to those of group 2: operating room time (4.7 and 4.1 h), median blood loss (200 and 100 ml), surgical margins for cancer (all negative), major complications (0% and 9%), and minor complications (18% and 14%). The median serum creatinine level was similar 2 mo postoperatively (1.2 and 1.3 mg/dl). The study was limited by the relatively small sample size.

Conclusions

Anatomic targeted dissection and superselective control of tumor-specific renal arterial branches facilitate zero-ischemia PN. Even challenging medial and hilar tumors can be excised without hilar clamping. Global surgical renal ischemia has been eliminated for most patients undergoing PN at our institution.  相似文献   
19.
OBJECTIVE: To shed light on the discrepancy between the advanced stage at presentation and high recurrence rate of well-differentiated thyroid cancer in children and the overall good survival. DESIGN AND METHODS: The files of 75 children with well-differentiated thyroid cancer treated from 1954 to 2001 in a major tertiary-care hospital were reviewed for disease course, management, and outcome. RESULTS: Sixty patients (80%) had positive neck metastases with involvement of central compartment lymph nodes in all, lateral neck nodes in 36, and distant metastases in 4. Sixty-seven patients underwent total thyroidectomy with adjuvant radioiodine treatment and 8 underwent hemithyroidectomy; all had concomitant neck treatment. The rate of local (5%) and neck (9%) recurrence was similar to the total rate reported in adults. Total thyroidectomy led to a significantly lower recurrence rate (7.5%) than hemithyroidectomy (38%; P < 0.005). Type of neck dissection did not affect recurrence or appearance of distant metastases. All deaths (n = 2) were due to distant metastases, whereas 30% of adult deaths are due to local or neck disease. CONCLUSIONS: The treatment of choice for well-differentiated thyroid cancer in young patients is total thyroidectomy. Neither regional disease at presentation nor recurrences affect survival.  相似文献   
20.
Spinal fusion via anterior lumbar interbody fusion (ALIF) can offer symptomatic relief to patients that suffer severe low back pain, radiculopathy, and claudication. However, a detailed working knowledge of the thoracic, abdominal, and lumbar anatomy, particularly of the vasculature, is vital. We report the case of a 68‐year‐old man who presented with radiculopathy and progressively worsening low back pain despite 9 months of unsuccessful conservative therapy and pain management. Preoperative computed tomography and magnetic resonance imaging revealed a rare anatomical variation, with an anomalous left‐sided inferior vena cava and anomalous aorta. The patient was surgically treated with ALIF at L4,5 and L5S1 via an altered surgical window. Given the anomalous anatomy of the patient, instead of performing the procedure after mobilizing both of the transposed abdominal great vessels, the inferior vena cava and the abdominal aorta, the ALIF was uneventfully performed in the window between these vessels. There were no perioperative or postoperative complications. At 12‐week postoperative follow‐up, X‐ray imaging demonstrated successful implantation of ALIF cages with no recurrence of symptoms. A detailed working knowledge of anatomy is important, particularly if anatomical variations are present. This has implications for preoperative surgical planning, which is integral to the safety and the success of procedures.  相似文献   
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