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91.
OBJECTIVES: To review pathologic diagnoses of multiple enhancing lesions in a unilateral breast detected on dynamic helical computed tomography (CT)-mammography and to correlate imaging findings with pathologic results. METHODS: From May 1998 to July 2001, preoperative contrast-enhanced helical CT scanning of the breast was performed in 200 female patients clinically diagnosed with breast cancer. The patients were scanned in the prone position in a specially designed CT-compatible device, with rapid intravenous bolus injection of 100 mL contrast material. Three-dimensional maximum intensity projection images were reconstructed. The cases with multiple enhancing lesions in a unilateral breast were retrospectively reviewed. The maximum diameter of the largest stain in each breast was measured, the patterns of multiple enhancing lesions were classified, and imaging findings were correlated with surgical and pathologic outcomes. RESULTS: Twenty-five of 200 (12.5%) patients (age range: 39-86 years, mean age: 56 years) showed multiple stains on CT-mammography. Two patients showed multiple stains in bilateral breasts. The maximum diameter of the largest stain in each breast ranged from 5 to 55 mm (average: 22 mm). Among cases with multiple stains, 21 (78%) were shown to be invasive ductal carcinoma with multiple satellite cancer nodules. Four cases were ductal carcinoma in situ with multiple satellite nodules. One case revealed multiple fibroadenomas, and another showed intraductal papilloma. CONCLUSIONS: Multiple enhancing lesions on CT-mammography in patients with breast cancer were relatively common, and most of them represented multiple cancer lesions. Dynamic CT-mammography is potentially useful in evaluating the spread of breast cancer.  相似文献   
92.
A Roux-en-Y choledochojejunostomy (CDJ) has been the sole method of choice for the reconstruction of the bile duct in living-donor liver transplantation (LDLT) using left-lobe grafts. In this study, we evaluated the feasibility of duct-to-duct (DD) biliary reconstruction in adult-to-adult LDLT using left-lobe grafts. Between October 1996 and October 2001, 46 adult-to-adult LDLTs using the left lobe were performed at our institution. The DD biliary reconstruction (hepaticocholedochostomy) over a T-tube was performed for seven of the last nine recipients (DD group, n=7), whereas the conventional Roux-en-Y CDJ was used for the remaining cases (CDJ group, n=39). The technical problems and the incidence of biliary complications were compared between the groups. Bile leakage developed in only 1 of 7 (14%) in the DD group (leakage from a T-tube exit site), whereas it occurred in 8 of 39 (20%) in the CDJ group. Up to now, no patients from the DD group developed anastomotic stricture, whereas twelve (30.7%) patients from the CDJ group did. Other complications included bleeding from the Roux-en-Y jejunojejunostomy (n=1) and anastomotic occlusion caused by an internal stent (n=1), and both complications were associated with CDJ. In conclusion, DD anastomosis is a simple and viable option for biliary reconstruction in left-lobe LDLTs. A long-term follow-up, especially regarding the incidence of biliary stricture, is thus warranted in such patients.  相似文献   
93.
BACKGROUND: Combination chemotherapy of methotrexate, actinomycin D and cisplatin (MAP) is reported to be effective against gestational choriocarcinoma. METHODS: Eight patients with metastatic testicular cancer who had elevated beta-hCG were treated with MAP. They included three refractory cases and two relapsed cases. An additional three patients received MAP as part of the induction therapy. The MAP therapy consisted of methotrexate (10 mg/m2) on days 1-5, actinomycin D (0.01 mg/kg) on days 1-5 and cisplatin (70 mg/m2) on day 1. RESULTS: In all three refractory patients, MAP failed to achieve tumor marker normalization. However, the elevated tumor markers normalized after MAP in the two cases of relapse. Of these two, one patient relapsed again 7 months after MAP and was subsequently salvaged with high-dose chemotherapy. The other patient relapsed and died of the disease 30 months after receiving MAP. Of the three patients who received MAP as part of the induction chemotherapy, one with pure choriocarcinoma achieved tumor marker normalization after MAP and is still alive without disease progression. In the other two patients, MAP failed to achieve marker normalization and the patients received high-dose chemotherapy. The toxicities were mainly bone marrow suppression and mucositis, which were almost acceptable. CONCLUSIONS: The results demonstrated the limited efficacy of MAP as salvage therapy. In addition, the efficacy of MAP as part of induction chemotherapy was negligible. However, there might be some role for MAP as a salvage therapy for patients with pure choriocarcinoma.  相似文献   
94.
In this study, we present a magnetic resonance imaging (MRI) method for quantifying cerebral deoxyhemoglobin content that is based on a measurement of the reversible contribution (R'2) of the transverse relaxation rate under the assumption of a quantitative relationship between R'2 and deoxyhemoglobin content. A numerical simulation was performed assuming a specific pulse sequence conventionally employed for R'2 measurement. The results showed a near linear relationship between R'2 and deoxyhemoglobin content in the physiological range of oxygen extraction for almost all sized vessels, although a large diffusion effect for capillary sized vessels compromised the relationship. Concerning the methodology for R'2 measurement, a theoretical analysis showed that multiexponential transverse signal decay of brain parenchyma may result in a considerable underestimation or overestimation of R'2, if a conventional method is employed for R'2 quantification. A modified method for correcting the effect of multiexponential signal decay was employed for R'2 measurement of the brain in normal volunteers. The results showed a high level of agreement between the R'2 values measured in our study and those estimated from physiological parameters obtained using other modalities such as PET. In the context of BOLD contrast-based functional MRI, the method proposed provides a quantitative mapping of baseline cerebral deoxyhemoglobin content, which is the essential physiological parameter for calibrating the stimulation-induced BOLD signal change and mapping neuronal activity in a quantitative manner by functional MRI.  相似文献   
95.
Two cases of histopathologically advanced (stage IV) early gastric cancers   总被引:3,自引:0,他引:3  
We report two cases of early gastric cancer with distant metastases (stage IV). At our institute 1428 cases of primary gastric cancer were resected between 1980 and 1997; 536 were diagnosed as early gastric cancer based on the resected specimens (304 cases of mucosal cancer, Tis--TNM classification--and 232 of submucosal cancer, T1). 528 of these 536 cases were classified as histological stage I, six as stage II, none as stage III and two as stage IV. The incidence of stage IV early gastric cancer was 0.14% of all gastric cancers and 0.37% of the early gastric cancers. The two patients with stage IV early gastric cancer were women. Both tumors were defined as early cancer because they were confined to the submucosa. One was a type 0 IIc + III early cancer, histologically classifiable as a small, moderately differentiated adenocarcinoma (tub2 according to the Japanese Classification of Gastric Carcinoma, G2; TNM classification: ICD-O C16), size 10 x 8 mm; the other was a surface spreading type 0 IIc, classifiable as a signet-ring cell carcinoma (sig, G3), size 50 x 35 mm. Stage IV factors were N3 in the first and ovarian metastasis (Krukenberg tumor) in the second case.  相似文献   
96.
To clarify the pathophysiological mechanism of postural orthostatic tachycardia syndrome (POTS). the responses of heart rate and the plasma cyclic AMP (cAMP) level to isoproterenol infusion in the supine position were evaluated in 10 POTS patients and 10 age-matched controls. Also, the effect of beta-adrenergic blockade on POTS was assessed using the headup tilt test. The POTS patients consisted of two men and eight women, with a mean age of 19.7 years (range. 15-28 years). An exaggerated increase of both heart rate and the plasma cAMP concentration after isoproterenol infusion at a low dose (1 microg/min) was observed in the POTS patients, but not in control subjects. Seven POTS patients received oral beta-blocker therapy. In five of these, symptoms were abolished and there was a smaller heart rate increase during the head-up tilt test. These data suggest that POTS may be more prevalent in young women and that beta-adrenergic hypersensitivity may play a role in the mechanisms of this syndrome. However, a larger series of patients need to be studied in the future.  相似文献   
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99.
Objective:   The purpose of this study was to investigate the effects of eviprostat, a phytotherapeutic drug, on bladder overactivity and inflammation in a cyclophosphamide (CYP)-induced cystitis rat model.
Methods:   Female Sprague-Dawley rats received a single intraperitoneal injection of CYP (200 mg/kg) or saline. After the CYP injection, eviprostat (9, 18 or 54 mg/kg per day) or a vehicle was orally given twice each day. Four days after the CYP injection, bladder function was evaluated by cystometrograms under urethane anesthesia. In a separate group, bladder inflammation was compared between the eviprostat- or vehicle-treated animals. Furthermore, the effects of eviprostat on carbachol-induced muscle contraction were evaluated by an in vitro experiment.
Results:   The intercontraction interval (ICI) significantly decreased in the CYP-injected rats in comparison to the saline-injected rats. In the CYP-injected group, 18 and 54 mg/kg per day of eviprostat treatment significantly increased the ICI, but did not change the maximum voiding pressure in comparison to the vehicle treatment. In the saline-injected group, no significant changes of any parameters in the cystometrograms were observed between the eviprostat- and vehicle-treated groups. CYP-induced bladder inflammation tended to be lower in the eviprostat-treated group in comparison to the vehicle-treated group. An in vitro experiment revealed that eviprostat failed to inhibit carbachol-induced muscle contraction.
Conclusion:   The oral administration of eviprostat suppressed CYP-induced bladder overactivity. The effects of eviprostat on the micturition reflex may be irrespective of antimuscarinic action. The present findings raise the possibility that eviprostat could be an effective treatment for bladder overactivity associated with inflammation.  相似文献   
100.
The case of a 53-year-old female with interstitial pneumonitis is described with special regard to biochemical characterization of pulmonary corpora amylacea which were found in the lung specimen obtained by bronchial biopsy from the patient. The main protein component in bronchoalveolar lavage (BAL) fluid of the patient was albumin, but proteins in the precipitate fraction of BAL fluid, where the corpora amylacea were recovered, predominantly consisted of 36 kD protein which was stained with the monoclonal antibody PE 10 to human pulmonary surfactant apoprotein by immunoblot. Histologically the pulmonary corpora amylacea were stained with eosin and PAS. The particles were stained immunohistochemically by immunoperoxidase reaction using PE 10, but not by antibodies to human albumin. The pulmonary surfactant apoprotein seems, therefore, to be not simply adsorbed in the particles, but to be contained in them. Thus, the surfactant apoprotein may, at least in this case, be involved in the formation of pulmonary corpora amylacea.  相似文献   
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