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61.
62.
AimsThe purpose of this study was to investigate the repair processes of experimental intra-alveolar root fractures of immature rat molars with histopathological techniques and 3-dimensional micro-computed X-ray tomography (3D micro-CT) imaging.MethodsTwelve left upper first molars of 4-week-old rats were dislocated toward the palate with modified Hoe's pliers at a load of 900 g for 20 s, and repositioned. After 1 or 2 weeks, the maxillae were dissected and scanned with micro CT for 3D micro-CT imaging. After standard histological preparation, buccolingual serial sections of the maxillae were stained with hematoxylin and eosin or Masson–Goldner stain and observed by light microscopy. Subsequently, we examined the identified root fracture lesions by 3D micro-CT imaging and histopathological sections.ResultsWe identified 6 intra-alveolar vertical incomplete fracture lines in the mesial roots. Histopathological findings showed that newly differentiated odontoblast-like cells had formed immature reparative dentin on the pulpal side of the fracture line at 1 postoperative week, and deposited reparative dentin with a tubular structure at 2 weeks. While surface resorption and granulation-tissue formation occurred on the periodontal side of the fracture line, the narrow fracture line remained unchanged, and the surface resorption lacunae were partly covered with cementum at postoperative 2 weeks.ConclusionsRoot-fracture investigation requires a combination of histopathological observation and 3D-CT imaging. Intra-alveolar fractured root repair accompanied by tubular reparative dentin formation at the pulpal side, and the deposition of cementum at the periodontal side, may occur when the fracture line is too narrow for the formation of granulation tissue.  相似文献   
63.
The MERA monopivot centrifugal pump has been developed for use in open‐heart surgery, circulatory support, and bridge‐to‐decision for up to 4 weeks. The pump has a closed‐type, 50‐mm diameter impeller with four straight paths. The impeller is supported by a monopivot bearing and is driven by a radial‐flux magnet‐coupling motor. Because flow visualization experiments have clarified sufficient pivot wash and stagnation at the sharp corner of the pivot support was suggested, sharp corners were removed in the design stage. The index of hemolysis of the pump operating at more than 200 mm Hg was found to be lower than that of a commercial pump. Four‐week animal tests were then conducted two times; improvement of thrombus formation was seen in the female pivot through modification of female pivot geometry. Overall antithrombogenicity was also recorded. Finally, to assure mid‐term use, an additional 4‐week durability test revealed that the rate of the axial pivot wear was as small as 1.1 µm/day. The present in vitro and in vivo studies revealed that the MERA monopivot centrifugal pump has sufficient hemocompatibility and durability for up to 4 weeks.  相似文献   
64.
65.

Purpose

We describe a new rat model of biliary atresia, induced by biliary ablation with pure ethanol.

Methods

A catheter was inserted and fixed in the common bile duct of male rats. Saline or pure ethanol was injected through the catheter and the animals were monitored for 8 weeks thereafter. We measured total bilirubin (T-Bil), aspartate aminotransferase (AST), alanine transaminase (ALT), and hyaluronic acid (HA) and examined liver biopsy specimens immunohistochemically for α-smooth muscle actin staining (α-SMA) and transforming growth factor-β1 (TGF-β1).

Results

The ethanol injection group animals were further divided into a temporary and a persistent liver dysfunction group. In the persistent group, T-Bil, AST, ALT and HA levels were significantly higher after 8 weeks in the persistent group than in the control group and the temporary group. In the ethanol injection group, α-SMA expression was prominent in the surrounding proliferative bile ducts and portal areas. The distribution of TGF-β1 was found prominently in hepatocytes in the center of nodules and in ductular epithelial cells.

Conclusions

This study characterizes the effects of ethanol-induced bile duct injury in rats, resulting in sclerosing cholangitis and its secondary effects. We believe that this experimental model will prove useful in the study of biliary atresia.  相似文献   
66.
ABSTRACT

Purpose/Aim: Although several prognostic factors for extrahepatic cholangiocarcinoma (EHC) have been reported, preoperative prognostic factors have yet to be established. We investigated the serum concentration of angiogenic, inflammatory, and nutritional parameters. Materials and Methods: Twenty-five patients with EHC were enrolled before starting treatment. Preoperative prognostic factors were identified using multivariate analyses. Results: The serum soluble intercellular adhesion molecule-1 (sICAM-1) levels were significantly higher in the patients with EHC (436.0 ± 43.2 ng/ml) than in the healthy volunteers (228.6 ± 22.0 ng/ml) (p <.001). In addition, the serum IL-6 levels were significantly higher in the patients (18.0 ± 5.6 pg/ml) than in the healthy volunteers (5.7 ± 0.8 pg/ml) (p <.05). The serum IL-6 and sICAM-1 showed a strong correlation (r = 0.559) in the patients with EHC (p <.01). The serum IL-6 (area under the curve = 0.764, p =.030, cut-off level = 11.6) and sICAM-1 (area under the curve = 0.818, p =.007, cutoff level = 322.6) were revealed to be useful as prognostic factors by the receiver operating characteristic curves. The high IL-6 group and the high sICAM-1 group showed poorer DSS than those of the respective low groups. In the multivariate analysis, IL-6 (hazard ratio: 1.050, 95% confidence interval: 1.002–1.100, p =.043) and sICAM-1 (hazard ratio: 1.009, 95% confidence interval: 1.002–1.015, p =.009) were independent prognostic factors for DSS. Conclusions: IL-6 and sICAM-1 were independent preoperative prognostic factors in EHC patients, causing continuous inflammation and malnutrition in collaboration with other pro-angiogenic factors.  相似文献   
67.

Background

The purposes of this study were to clarify the risk factors for supraclavicular lymph node (SCLN) metastasis and the survival benefit from cervical lymph node (LN) dissections in patients with clinically submucosal (cT1b) carcinoma of the thoracic esophagus.

Methods

A total of 86 patients with this disease who underwent esophagectomy with 3-field lymph node dissection were retrospectively reviewed. Multivariate logistic regression and Cox proportional hazard model were used to identify the independent risk factors for SCLN metastasis and prognostic factors, respectively. An index calculated by multiplying the frequency of metastasis at nodal basin and the 5-year overall survival rate of patients with metastasis at that basin were used to assess the therapeutic outcomes.

Results

A total of 40 patients (47 %) were found to have pathological LN metastasis. Also, 13 patients (15 %) had cervical LN metastasis: 6 and 7 with carcinoma of the upper and mid-thoracic esophagus, respectively. SCLN metastasis was found in 6 patients (7 %); however, there was no independent risk factor for SCLN metastasis. The 5-year overall survival rate was 72.5 %. Cervical LN metastasis was an independent prognostic factor (p = .04; odds ratio 2.55; 95 % confidence interval 1.03–6.31); however, there was no significant difference in survival between patients with SCLN metastasis and those without (p = .06). The calculated index of estimated benefit from cervical LN dissections was 6.9, following upper mediastinal LN of 15.6 and perigastric LN of 8.3.

Conclusions

We could not identify risk factors to predict SCLN metastasis. Cervical LN dissection should not be omitted in patients with cT1b carcinoma, especially of the upper and mid-thoracic esophagus.  相似文献   
68.
We describe a new technique for the treatment of cryptotia by which stitches for bolster fixation are inserted parallel to the auriculartemporal sulcus and temporarily left untied. After the bolster has been inserted into the temporal sulcus, the corresponding ends of the threads are tied to each other. Our technique is easy to use and secures a firm bolster fixation, and we recommend it for the treatment of cryptotia.  相似文献   
69.
INTRODUCTIONWe present a rare case of mesenteric lymphangioma in a middle-aged female.PRESENTATION OF CASEA 56-year-old female was admitted to the hospital with upper abdominal pain. Abdominal computed tomography revealed a multicystic mass surrounding the mesentery. We made the decision to resect the mass, suspecting that was a mesenteric lymphangioma based on additional imaging studies. The tumor adhered strongly to parts of the duodenum and the upper jejunum. In order to preserve the jejunum, we dissected its serosa away from the tumor. Approximately 1 week after surgery the patient experienced a constriction of the third portion of the duodenum. Her symptoms were improved with conservative therapy, and she was discharged from the hospital 62 days after surgery.DISCUSSIONLymphangioma originating from the mesentery may have cause adhesions due to exfoliated tumor cells; it is necessary to be concerned about postoperative obstruction.CONCLUSIONThe preoperative diagnosis of lymphangioma is based on various imaging modalities.  相似文献   
70.
Abstract

A 56-year-old female with an initial symptom of unilateral progressive visual disturbance presented with a clinoidal meningioma arising from a falciforme process of the optic canal. Magnetic resonance images with gadolinium-diethylenetriaminepenta-acetic acid demonstrated marked enhancement of a small mass, approximately 1 cm in diameter, roofing the right optic nerve at the intracranial opening of the optic canal. The clinoidal meningioma is rarely reported and the precise originating location of the neoplasm has not been clarified. This is the first case of clinoidal meningioma, which is confirmed by the operative observation as the origin of the neoplasm is a falciforme process of the optic canal. Magnetic resonance images with enhancement are useful for the diagnosis of such a small neoplastic lesion adjacent to bone structure and total removal without a deterioration of visual function is achieved by careful microsurgical procedure. [Neurol Res 1996; 18: 237–240]  相似文献   
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