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101.
PURPOSE: Strontium-89 chloride (89Sr) is a new radiopharmaceutical that provides effective pain relief for metastatic bone lesions, and is expected to be available soon in the palliative management for metastatic bone pain in Japan. Because of relatively long physical half life (50.5 days), 89Sr may affect to the radioactive draining-water system by exceeding the limits of activity concentration for radioactive drain. In this article, the influence of 89Sr use on the radioactive drainage system was simulated. METHODS: The standard tank capacity of drainage and draining frequency was determined from the results of questionnaire carried out for the nationwide medical and research institutes where radioisotope treatment are performed. On the assumption that 89Sr of 148 MBq for one therapy was used twice a week and several common radionuclides were used as the same activity as used at Chiba Cancer Center, the influence of 89Sr was estimated. The calculation was performed using the activity contamination ration into the draining-water system of each radionuclide of 0.01, which was legally determined. RESULTS: The simulation revealed that the sum of the contamination ratios of individual radionuclides exceeded a legal value of 1.0 in standard drainage with the capacity of 5 m3 and 10 m3 and draining frequency of 7 times per year. The actual contamination ratios of common radiopharmaceuticals measured at Chiba Cancer Center ranged from 1/100 to 1/1000 of the legal values. CONCLUSION: It is necessary that the legal value of activity contamination ratios into the draining-water system should be reassessed before starting 89Sr therapy.  相似文献   
102.
Encapsulated hepatocyte transplantation is a promising approach to cell transplantation without immunosuppression as an alternative to whole organ liver transplantation. However, the shortage of donor cells for hepatocyte transplantation has not been resolved, and at this critical point, it seems necessary to establish a method of hepatocyte cryopreservation to allow clinical application of hepatocyte transplantation and the development of a bioartificial liver system in the near future. In this study we demonstrated that cryopreserved microencapsulated rat and human hepatocytes can retain their hepatic function and that cryopreserved microencapsulated human hepatocytes transplanted into rat spleen remain viable without immunosuppression. Rat and human hepatocytes were isolated by a collagenase digestion method, and they were microencapsulated with poly-L-lysine. The microencapsulated rat hepatocytes were transferred to culture medium (DMEM containing 10% FBS and 10% DMSO) and immediately frozen in liquid nitrogen. A warm water bath (37 degrees C) was used to thaw the microencapsulated hepatocytes. Hepatic function, drug metabolism, and cell morphology were assessed after 90 days of cryopreservation. After 1 week of cryopreservation, microencapsulated hepatocytes were cultured for up to 2 weeks to assess their hepatic function and morphology. The morphology of human hepatocytes was assessed after 30 days of cryopreservation. Cryopreserved human hepatocytes were transplanted into rat spleen to assess their morphology. Cryopreserved microencapsulated hepatocytes retained their viability and were strongly positive for expression of albumin, OAT2, CYP3A2, and CYP3A9. Two weeks after cultivation, the cryopreserved microencapsulated rat hepatocytes had retained their hepatic function (urea synthesis). Cryopreserved microencapsulated human hepatocytes also mainly survived and retained their hepatic function for at least 30 days after cryopreservation. Moreover, entrapped cryopreserved human hepatocytes also survived and expressed albumin in rat spleen after transplantation. We demonstrated a novel method of long-term cryopreservation of rat and human hepatocytes by using an encapsulation technique, with retention of biological activity and excellent survival of the cryopreserved microencapsulated human hepatocytes transplanted into rat spleen. We believe that this novel approach to hepatocytes cryopreservation provides a new direction in encapsulated cell therapy with the goal of clinical application in the near future.  相似文献   
103.
BACKGROUND: Major pulmonary resection with systematic node dissection (SND) for early lung cancer by video-assisted thoracic surgery (VATS) is performed in many institutes, but the feasibility of SND for early lung cancer by VATS remains controversial. The aim of this study was to elucidate the feasibility and safety of SND by VATS. METHODS: Three hundred fifty patients with clinical stage I lung cancer who underwent pulmonary major resection with SND between 1998 and 2003 were enrolled in this study. Of these patients, 191 (VATS group) underwent pulmonary resection with SND by VATS; 159 patients (open thoracotomy [OT] group) did so through anterolateral thoracotomy. The clinical and pathologic data, including the number of dissected nodes in each nodal station, of the 2 groups were compared to evaluate the feasibility of SND by VATS. RESULTS: Pathologic data showed that, in the VATS group, more patients had adenocarcinoma (P = .0078) and fewer patients had advanced factors than the OT group. The greatest tumor diameter was 24.5 mm and 29.6 mm in the VATS group and OT group, respectively (P < .0001). The total number of mediastinal nodes dissected in right upper lobectomy plus right middle lobectomy (RUL+RML), right lower lobectomy (RLL), left upper lobectomy (LUL), and lower left lobectomy (LLL) also did not differ between the 2 groups. The total number of mediastinal nodes dissected in RUL+RML, RLL, LUL, and LLL was 19.7 in the VATS group versus 22.0 in the OT group (P = .122), 23.4 versus 21.0 (P = .241), 14.8 versus 17.5 (P = .123), and 18.8 versus 15.8 (P = .202), respectively. The number of dissected nodes in each nodal station in RUL+RML, RLL, LUL, and LLL was similar between the 2 groups. Operative mortality, morbidity, or recurrence did not differ between the 2 groups. CONCLUSIONS: With regard to the number of dissected nodes, SND by VATS was not inferior to that of OT. SND by VATS is technically feasible and safe, and seems acceptable for clinical stage I lung cancer.  相似文献   
104.

Objectives

To evaluate the use of diffusion-weighted imaging (DWI) for estimating infarcted splenic volume during partial splenic embolisation (PSE) using n-butyl cyanoacrylate (NBCA).

Methods

Twenty consecutive patients (57.2?±?11.7 years) with hypersplenism underwent PSE. Intrasplenic branches were embolised using NBCA via a 2.1-French microcatheter aiming at infarction of 50 to 80 % of total splenic volume. Immediately after PSE, signal intensities (SI) of embolised and non-embolised splenic parenchyma were measured on DWI. Semi-automated volumetry (SAV) on DWI was compared with conventional manual volumetry (MV) on contrast-enhanced CT 1 week after PSE. Platelet counts were recorded before and after PSE.

Results

The SI on DWI in the embolised parenchyma decreased significantly (P?<?0.01) to 24.7?±?8.1 % as compared to non-embolised parenchyma. SAV and MV showed a strong correlation (r?=?0.913 before PSE, r?=?0.935 after PSE, P?<?0.01) and significant (P?<?0.01) reduction of normal splenic volume was demonstrated on both SAV (71.9?±?12.4 %) and MV (73.6?±?9.3 %) after PSE. Based on the initial SAV, three patients (15 %) underwent additional branch embolisation to reach sufficient infarction volume. Platelet counts elevated significantly (522.8?±?209.1 %, P?<?0.01) by 2 weeks after PSE. No serious complication was observed.

Conclusion

Immediate SI changes on DWI after PSE allowed semi-automated splenic volumetry on site.

Key Points

? Partial splenic embolisation (PSE) is an important interventional technique for hypersplenism ? Diffusion-weighted MR reveals an immediate decrease in signal in the embolised parenchyma ? Such signal reduction permits semi-automated splenic volumetry on site. ? This allows precise quantification of the amount of parenchyma infarcted, avoiding additional PSE.  相似文献   
105.

Objectives

Structural and functional changes in pulmonary vessels are prevalent at the initial stages of chronic obstructive pulmonary disease (COPD). These vascular alterations can be assessed using cross-sectional area (CSA) of small pulmonary vessels. However, neither in non-COPD smokers nor in COPD patients it has been defined whether the structural changes of pulmonary vessels detected by paired inspiratory and expiratory CT scans are associated with emphysematous changes. We quantified the CSA and low attenuation area (LAA) and evaluated the changes in these parameters in the inspiratory and expiratory phases.

Materials and methods

Fifty consecutive non-COPD smokers and COPD patients were subjected to multi detector-row CT and the percentage of vessels with a CSA less than 5 mm2 as well as the percentage LAA for total lung area (%CSA < 5, %LAA, respectively) were calculated.

Results

The %CSA < 5 correlated negatively with %LAA. The %CSA < 5 was lower in COPD patients with emphysema as compared with non-COPD smokers and COPD patients with or without mild emphysema. In addition, the %CSA < 5 was lower in the no/mild emphysema subgroup as compared with non-COPD smokers. The respiratory phase change of %CSA < 5 in COPD patients was greater than that in non-COPD smokers.

Conclusion

The percentage of small pulmonary vessels decreased as emphysematous changes increase, and this decrease was observed even in patients with no/mild emphysema. Furthermore, respiratory phase changes in CSA were higher in COPD patients than in non-COPD smokers.  相似文献   
106.
PURPOSE: The aim of this study was to evaluate the usefulness of computer-aided detection (CAD) in diagnosing early colorectal cancer using computed tomography colonography (CTC). MATERIALS AND METHODS: A total of 30 CTC data sets for 30 early colorectal cancers in 30 patients were retrospectively reviewed by three radiologists. After primary evaluation, a second reading was performed using CAD findings. The readers evaluated each colorectal segment for the presence or absence of colorectal cancer using five confidence rating levels. To compare the assessment results, the sensitivity and specificity with and without CAD were calculated on the basis of the confidence rating, and differences in these variables were analyzed by receiver operating characteristic (ROC) analysis. RESULTS: The average sensitivities for the detection without and with CAD for the three readers were 81.6% and 75.6%, respectively. Among the three readers, only one reader improved sensitivity with CAD compared to that without. CAD decreased specificity in all three readers. CAD detected 100% of protruding lesions but only 69.2% of flat lesions. On ROC analysis, the diagnostic performance of all three readers was decreased by use of CAD. CONCLUSION: Currently available CAD with CTC does not improve diagnostic performance for detecting early colorectal cancer. An improved CAD algorithm is required for detecting flat lesions and reducing the false-positive rate.  相似文献   
107.
PURPOSE: Primary symptoms were reviewed retrospectively in patients with prostate cancer diagnosed in our hospital with the aim of promoting early detection. MATERIALS AND METHODS: The subjects included 301 cases with prostate cancer diagnosed histologically in Nagoya Urology Hospital from August, 1988 to December, 2001. The mean age was 72.7 years, and the median PSA was 20.0 ng/ml. Primary symptoms were classified according to the General Rule for Clinical and Pathological Studies on Prostate Cancer (The 3rd Edition). RESULTS: Out of 301 cases, 274 (91%) visited our hospital with clinical symptoms. Of them, 272 had primary urological symptoms. In these 272 cases, 250 (92%) and 19 (7%) had lower urinary tract symptoms (LUTS) and macroscopic or microscopic hematuria, respectively. The majority of patients (82%) referred from other urologists had already undergone PSA measurement, compared to 50% in those referred from physicians other than urologists (p < 0.0005). CONCLUSION: The present data revealed that LUTS were important primary symptoms for the detection of prostate cancer, particularly in an area like Nagoya where the mass screening for prostate cancer is still unavailable. In terms of the early detection of prostate cancer, PSA has to be measured in patients with LUTS even when they visit physicians who are not urologists.  相似文献   
108.
BACKGROUND: Target controlled infusion (TCI) for propofol allows anesthesiologists to target constant blood concentrations of propofol. However, the pharmacokinetic parameters in TCI system do not take account of the patient's age, make up and gender. We evaluated the relationship between body fat percentage and the estimated effect site propofol concentrations at awakening. METHODS: Anesthesia was induced in 37 patients with fentanyl and propofol by TCI. Patients's percentage of fat was evaluated by measuring the thickness of the three parts of the skin fat with Skyndex (Caldwell Justiss, USA). After surgery and discontinuation of anesthesia, the estimated effect site propofol concentrations (EPEC) were determined when the patient could respond to verbal command. RESULTS: The EPECs at awakening were 1.5 +/- 0.2 micrograms.ml-1 in male and 1.5 +/- 0.3 micrograms.ml-1 in female. In male, the percentage of fat and body mass index (BMI) correlated significantly with EPEC (r = 0.79 and 0.49 respectively). In female, the percentage of fat and BMI did not correlate with EPEC. The estimated fentanyl effect site concentrations at awakening did not correlate with the EPEC. CONCLUSIONS: Male patients who have high percentage of fat have a tendency to delayed of awakening from propofol anesthesia. In female, however, no correlation was seen between percentage of fat and awakening time from propofol anesthesia. Measuring the percentage of fat might bring a new insight into pharmacokinetics of propofol.  相似文献   
109.
背景 舟状骨骨折是竞技体育中常发生的致残性外伤.本研究评估使用捷迈公司生产的Herbert螺钉治疗年轻运动员舟状骨骨折的效果.方法 30例舟状骨骨折的运动员接受治疗.根据Herbert分类标准,其中10例为急性骨折(Ⅰ组),另外包括6例纤维连接(Ⅱ组)和14例为假关节(Ⅲ组);20例患者由于漏诊或内固定失败形成骨不连.结果 Ⅰ、Ⅱ、Ⅲ组术后形成明显骨连接的平均时间分别为9.2、8.0、11.9周,恢复运动能力的时间分别为10.7、14.0、22.9周.使用Mayo腕关节评分评价临床效果,Ⅰ、Ⅱ组表现优秀(分别为97.5和93.3分),Ⅲ组表现良好(85.4分).结论 及早确诊和治疗可使年轻运动员早期恢复运动能力.捷迈公司生产的Herbert螺钉技术治疗舟状骨骨折的临床效果出色.  相似文献   
110.
Intravesical Bacillus Calmette-Guerin (BCG) therapy is commonly used against superficial urothelial carcinoma, especially carcinoma in situ (CIS). We report a case of tuberculous epididymitis that occurred during a course of intravesical BCG therapy. A 76-year-old man had received intravesical BCG therapy for multiple superficial bladder cancer and CIS in prostatic urethra after transurethral resection of bladder tumor (TUR-Bt). He recognized hard nodules in the left scrotum after 4 times intravesical BCG therapy. Skin fistula in scrotum occurred 5 months later. We performed left orchiectomy with scrotum skin resection. Histological diagnosis was tuberculous epididymitis. Postoperatively, he was administered chemotherapy consisting of isoniazid, refampin and ethambutol.  相似文献   
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