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61.

Purpose

The purpose of this study is to clarify morphological changes of acetabular subchondral bone cyst after total hip arthroplasty for osteoarthritis secondary to developmental dysplasia of the hip.

Methods

Two hundred and sixty-one primary cementless total hip arthroplasties of 208 patients, 18 males, 190 females, were retrospectively reviewed. Morphological changes of subchondral bone cyst were evaluated by computed tomography (CT). The mean cross-sectional area of the cyst from CT scans at 3 months postoperatively and after 7–10 years (average 8.4 years) were compared.

Results

Acetabular subchondral bone cysts were found in 49.0% of all cases in preoperative CT scans. There was no cyst which was newly recognized in CT scan performed after postoperative 7–10 years. All the cross-sectional areas of the cysts evaluated in this study were reduced postoperatively.

Conclusions

This study revealed that acetabular subchondral bone cysts do not increase or expand after total hip arthroplasty and indicated that the longitudinal morphological change of acetabular bone cysts in patients of developmental dysplasia of the hip do not influence long-term implant fixation in total hip arthroplasty.
  相似文献   
62.

Background

Triple Negative Breast Cancer (TNBC) is defined by a lack of estrogen and progesterone receptor gene expression and by the absence of overexpression on HER2. It is associated to a poor prognosis. We propose to analyze the clinicopathologic and prognostic characteristics of this breast cancer subtype in a Mediterranean population originated or resident in the North of Morocco.

Methods

We conducted a retrospective study of 279 patients diagnosed with breast cancer between January 2010 and January 2015. Clinicopathologic and prognostic features have been analyzed. Disease-Free Survival (DFS) and Overall Survival (OS) have been estimated.

Results

Of all cases, forty-nine (17.6 %) were identified as having triple negative breast cancer with a median age of 46 years. The average tumor size was 3.6 cm. The majority of patients have had invasive ductal carcinoma (91.8 %) and 40.4 % of them were grade III SBR. Nodal metastasis was detected in 38.9 % of the patients and vascular invasion was found in 36.6 % of them. About half of the patients had an early disease (53.1 %) and 46.9 % were diagnosed at an advanced stage. Patients with operable tumors (61.2 %) underwent primary surgery and adjuvant chemotherapy. Patients with no operable tumors (26.5 %) received neoadjuvant chemotherapy followed by surgery, and patients with metastatic disease (12.2 %) were treated by palliative chemotherapy. DFS and OS at 5 years were respectively 83.7 and 71.4 %. Among 49, twelve had recurrences, found either when diagnosing them or after a follow-up. Local relapse was 6.1 %. Lung and liver metastases accounted consecutively for 8.2 and 10.2 %. Bone metastases were found in 4.1 % and brain metastases in 2.1 % of the cases.

Conclusion

Our results are in accordance with literature data, particularly what concerning young age and poor prognosis among TNBC phenotype. Therefore, the identification of BRCA mutations in our population seems to be essential in order to better adapt management options for this aggressive form of breast cancer.
  相似文献   
63.
General-purpose radiation transport Monte Carlo codes have been used for estimation of the absorbed dose distribution in external photon and electron beam radiotherapy patients since several decades. Results obtained with these codes are usually more accurate than those provided by treatment planning systems based on non-stochastic methods. Traditionally, absorbed dose computations based on general-purpose Monte Carlo codes have been used only for research, owing to the difficulties associated with setting up a simulation and the long computation time required. To take advantage of radiation transport Monte Carlo codes applied to routine clinical practice, researchers and private companies have developed treatment planning and dose verification systems that are partly or fully based on fast Monte Carlo algorithms. This review presents a comprehensive list of the currently existing Monte Carlo systems that can be used to calculate or verify an external photon and electron beam radiotherapy treatment plan. Particular attention is given to those systems that are distributed, either freely or commercially, and that do not require programming tasks from the end user. These systems are compared in terms of features and the simulation time required to compute a set of benchmark calculations.  相似文献   
64.
Adult T-cell leukemia (ATL) is a malignancy of mature lymphocytes caused by the retrovirus human T-cell lymphotrophic virus-I (HTLV-I). It is an aggressive leukemia with an overall mortality rate of 50% within 5 months; no conventional chemotherapy regimen appears successful in inducing long-term disease-free survival in ATL patients. However, ATL cells constitutively express high-affinity interleukin-2 receptors (IL-2Rs) identified by the anti-Tac monoclonal antibody, whereas normal resting cells do not. To exploit this difference in receptor expression, we administered anti-Tac intravenously (IV) to 19 patients with ATL. In general the patients did not suffer untoward reactions, and in 18 of 19 cases did not have a reduction in normal formed elements of the blood. Seven patients developed remissions that were mixed (1 patient), partial (4 patients), or complete (2 patients), with partial and complete remissions lasting from 9 weeks to more than 3 years as assessed by routine hematologic tests, immunofluorescence analysis, and molecular genetic analysis of T-cell receptor gene rearrangements and of HTLV-I proviral integration. Furthermore, remission was associated with a return to normal serum calcium levels and an improvement of liver function tests. Remission was also associated in some cases with an amelioration of the profound immunodeficiency state that characterizes ATL. Thus the use of a monoclonal antibody that blocks the interaction of IL-2 with its receptor expressed on ATL cells provides a rational approach for treatment of this aggressive malignancy.  相似文献   
65.
Nerve sheath tumors and meningiomas account for most intradural extramedullary (IDEM) tumors. These tumors are benign and amenable to complete surgical resection. In recent years, these surgeries are performed with intraoperative neurophysiologic monitoring (IONM) in order to minimize neurological injury, but the evidence for the statistical efficacy of this utility is lacking. This paper evaluates IONM benefits in IDEM tumor resection. Data of patients treated surgically for spinal intradural tumors from 1998 to 2003 was previously collected and analyzed. We retrospectively evaluated patients’ charts operated in the years 2011 to 2013. Patients’ medical files were reviewed including radiological examinations and electrophysiological reports. The data was collected and evaluated. Forty-one cases of meningioma or nerve sheath tumor resection surgery were performed in the study period. The surgical results were compared to 70 cases of historical controls. Demographic data was similar in these two groups. Sensitivity, specificity, and positive and negative predicted values of IONM were 75, 100, 100, and 97%, respectively. New neurological deficit rate was evident in 10 and 14% for the study and control groups, respectively (not significant). While IONM predicts neurological deficits with high accuracy level, this study does not suggest that there is a significant global benefit of IONM in these cases. As reported by others, in this series, the rate of new neurological deficits in non-monitored cases is similar to the monitored cases series; hence, IONM role in preventing new neurological deficits has yet to be proven.  相似文献   
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67.
Apoptosis and its augmentation by androgen withdrawal is an important event in the testis. In other tissues apoptosis is regulated by genes belonging to the bcl-2 family. However, little is known about these pathways in the human testes. Human testes were obtained from patients with prostate cancer, undergoing orchidectomy for permanent androgen ablative treatment. The patients were either untreated or had previously received short- or long-term anti-androgen therapy by cyproterone acetate or GnRH agonist (goserelin). In comparison with untreated patients, testicular testosterone concentrations were reduced by 83% in patients treated with cyproterone acetate and by 99% in patients treated with goserelin. Apoptotic cells were identified in tissue sections by in-situ end labelling of fragmented DNA. The expression of Bcl-2, Bcl-xl, Bax, p53 and poly(ADP) ribose polymerase (PARP) was demonstrated in tissue extracts by Western blotting. Apoptotic germ cells were present in the spermatogenic epithelium of untreated patients and patients who received short-term anti-androgen treatment. There were few or no apoptotic cells in the seminiferous tubules following long-term anti-androgen treatment. Following short- term treatment, the concentrations of the apoptosis-related proteins examined did not change. However, in the long-term treated testes, Bcl- xl and PARP expression declined, Bax and p53 protein concentrations were unchanged, and Bcl-2 was up-regulated. In conclusion, apoptosis occurs in spermatogenic cells of the human testis and may contribute to the regulation of germ cell populations. The apoptosis-related gene products which have been described in other tissues are present in the human testis and are modulated by androgenic stimuli.   相似文献   
68.
Laparoscopic surgery has many advantages but it is not withoutcomplications. The complexity of the surgery, significantlyinfluences the complication rate. Laparoscopic surgeons oughtto be aware of the possible complications and how they couldbe prevented, recognized without delay, and managed safely andefficiently. Important complications include injuries to thevessels, bowel and urinary tract. Incisional hernia ought tobe reduced by careful closure of the facia whenever a trocar=" BORDER="0">10 mm is used at the extraumbilical site. Gasembolism is a rare but potentially life threatening complication.Shoulder pain is a minor complication but is exceedingly common;it is less likely to occur if as much gas as possible is removedat the endo of the operation while the patient is still in headdown Trendelenburg position. Rare complications include pneumothorax,subcutaneous and pre-peritoneal emphysema, cardiac arrhythmia,nerve injury and venous thrombosis. Laparoscopic surgeons shouldalso understand the principles of electrosurgery and how toavoid complications arising from the use of electrical energyincluding capacitative coupling, direct coupling and insulationfailure.  相似文献   
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