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51.
BACKGROUND/AIMS: Hepatocellular carcinoma with portal venous invasion has a very poor prognosis. The aim of this study is to clarify the factors contributing to the survival of hepatocellular carcinoma patients with portal venous invasion. METHODOLOGY: Out of 952 patients with hepatocellular carcinoma admitted to Tokyo University hospital and its affiliated hospitals from 1987 to 1999, 53 patients developed portal venous invasion until December 2000. The main portal vein was invaded in 33 patients, and the first branch was invaded in the 20 patients. The factors contributing to the prognosis of hepatocellular carcinoma patients with portal venous invasion were determined by univariate and multivariate analyses using 19 clinicopathological parameters. RESULTS: Overall survival rates of the 53 patients at 6 months, and 1 and 2 years were 40%, 18%, and 12%, respectively. Univariate analysis indicated that the serum albumin level, Child classification, number of tumor foci, portal venous invasion-targeted irradiation, and percutaneous tumor ablation of the parenchymal main tumor were significant. Multivariate analysis showed that percutaneous tumor ablation (P = 0.033; risk ratio = 0.28) was the most important factor contributing to a favorable prognosis followed by number of tumor foci (P = 0.048; risk ratio = 0.41). CONCLUSIONS: This study showed the significance of treatment for the parenchymal main tumor in addition to portal venous invasion in patients with hepatocellular carcinoma involving portal venous invasion. Therefore, the efficacy of combined therapy using portal venous invasion-targeted irradiation and percutaneous tumor ablation for the parenchymal main tumor on survival of hepatocellular carcinoma patients with portal venous invasion is suggested.  相似文献   
52.

Background

The incidence of asymptomatic pulmonary Mycobacterium avium complex (MAC) disease appears to be increasing. This study aimed to determine the clinical characteristics and examine early outcomes of patients newly diagnosed with MAC disease.

Methods

We retrospectively reviewed the medical records of all 184 patients newly diagnosed with MAC disease between April 2013 and March 2015 at our hospital. Culture conversion, defined as at least two consecutive negative cultures, was used as the early outcome measure.

Results

Of 184 patients, 45 were male and 139 were female, with a mean age of 70 years. Abnormal chest shadow found during an annual health check-up (58 patients) or incidentally during visits for other diseases (72 patients), was the major reason for referral to hospital, typically with no symptoms. Anti-MAC IgA antibody was positive in 64.5% of patients, and the positive rate was associated with the extent of lesions. Clarithromycin-based multi-drug chemotherapy was initiated in 111 patients. Culture conversion was achieved in 61 of 82 (74.4%) patients who were able to continue multi-drug chemotherapy. Patients who achieved culture conversion were more likely to be younger, female, and have a lower smear grade and nodular-bronchiectatic type. Multivariate logistic regression analysis identified patient age and smear grade as predictive variables.

Conclusions

Abnormal chest shadow found during health check-up was the major reason for hospital visits, and most were asymptomatic. Culture conversion was achieved in three-fourths of patients treated, and was associated with age and smear grade, supporting early intervention at a younger age.  相似文献   
53.
Acute angle-closure glaucoma (AACG) is a rare complication of general anesthesia. The coexistence of individual risk factors for postoperative AACG and factors associated with intraocular hypertension are considered to be required for postoperative AACG to develop. We present a case of AACG after general anesthesia for oral bone grafting in a patient with no preoperative eye symptoms. In this case, several factors such as postoperative care in a darkened room, psychological stress, and postoperative hypertension may have precipitated the event in this patient, who may have had preexisting undiagnosed elevated intraocular pressure. The interval between the earliest appearance of symptoms at 9 hours and the ultimate diagnosis was 36 hours. In the postoperative period following general anesthesia, any patient is at risk for AACG. It is important that a postoperative diagnosis of AACG should be considered and a timely consultation with an ophthalmologist be considered if a postoperative patient complains of red eyes, visual disorder, eye pain, headache, and nausea.Key Words: Acute angle-closure glaucoma, General anesthesia, Postoperative ophthalmological emergencyAcute angle-closure glaucoma (AACG) is a rare complication of general anesthesia that can have a grave prognosis. Predicting AACG after general anesthesia is difficult. In addition, preventive measures against AACG after general anesthesia have not been established. To prevent poor outcomes, early diagnosis and appropriate treatment are important. We encountered a case of AACG after general anesthesia for oral bone grafting.  相似文献   
54.
ObjectivesSialolipoma has been classified as a benign soft tissue lesion in the 2017 World Health Organization classification of head and neck tumors. To our knowledge, only one case of laryngeal sialolipoma has been reported in the English literature. We conducted a retrospective study to identify clinical characteristics of supraglottic sialolipoma-like lesion and differentiate it from other supraglottic subepithelial masses.MethodsMedical records of 16 patients with supraglottic subepithelial benign mass lesions who underwent histological evaluation between 2003 and 2019 were retrospectively analyzed. Sialolipoma-like lesion was defined as a local finding of a well-circumscribed gross mass with pathological presence of salivary gland-like parenchymal lobules with evenly interspersed adipose tissue.ResultsEight patients showed histological positivity for sialolipoma-like lesion, 3 for amyloidosis, 2 for hemangioma, and 1 each for cyst, lymphoid hyperplasia, and chondrometaplasia. Sialolipoma-like lesion tended to be predominant among men; those affected had a mean age of 52.8 (range, 39–74) years. By contrast, among patients with amyloidosis, the ratio of men to women was 1:2 (100% vs. 33%; p = 0.055). Fiberscopic examination of all patients with sialolipoma-like lesions identified well-circumscribed, yellowish masses, closely resembling local amyloidosis findings. Sialolipoma-like lesion was associated with a significantly higher body-mass index (BMI; 27.4 ± 2.8 kg/m2) than amyloidosis (21.6 ± 1.4 kg/m2; p = 0.014). The transoral approach was used for lesion resection in all patients with sialolipoma-like lesion. No patient experienced postoperative recurrence.ConclusionLaryngeal sialolipoma-like lesion might be more prevalent than was previously reported, and histological examination is important to differentiate it from amyloidosis. Supraglottic sialolipoma-like lesion must be differentially diagnosed in patients with high BMI presenting with well-circumscribed, yellowish supraglottic masses.  相似文献   
55.
Heart transplantation started in Japan in 1999. Since then, 50 transplants have been performed at our center. We performed histopathological analyses of the 50 explanted hearts and the post‐transplant biopsy specimens. The median age of recipients was 39 years. The primary diseases before transplant were idiopathic dilated cardiomyopathy in 33 patients (66%), hypertrophic cardiomyopathy in seven (14%), restrictive cardiomyopathy in one, arrhythmogenic right ventricular cardiomyopathy in one, and secondary cardiomyopathy in eight (16%). Before transplantation, 47 patients (94%) had left ventricular assist devices. No severe cardiovascular failure due to allograft rejection occurred. The post‐transplant survival rate was 97.6% at 1 year and 93.1% at 10 years. One recipient was lost to sepsis from myelodysplastic syndrome in the fourth year, one died of multiple organ failure and peritonitis 8 months after transplant. Another patient died of recurrent post‐transplant lymphoproliferative disorders (PTLD). Mild cardiac dysfunction occurred in seven recipients in the early postoperative period. Moderate acute cellular rejection occurred in six patients (12%), and antibody‐mediated rejection occurred in three (6%). The number of heart transplants performed in Japan is very small. However, the outstanding 10‐year survival rate is due to donor evaluation and post‐transplant care resulting in low grade rejection. Pathological evaluation has also greatly contributed to the results.  相似文献   
56.
Ventricular assist devices (VADs) have long been used as bridge to transplant therapy (BTT). Nipro-Toyobo paracorporeal pulsatile-flow VAD (nt-VAD) was the only device available until April 2011, when implantable continuous-flow VADs (cf-VADs) became available. Although cf-VADs are central to BTT, nt-VAD remains a necessary option. We aimed to clarify the role of nt-VAD in an era of increasing cf-VAD use. We retrospectively reviewed patients who underwent VAD implantation at the National Cerebral and Cardiovascular Center from May 2011 to March 2013. Characteristics were compared between the nt-VAD and cf-VAD groups. Twenty-nine patients (mean age 37.7 ± 11.1 years, 23 males) underwent VAD implantation. Fifteen patients initially received nt-VADs, although 4 were converted to cf-VADs. Of these 15 patients, 3 were too small for cf-VADs and 2 needed bilateral ventricular support. The remaining 10 patients received nt-VADs (7 patients at INTERMACS level 1 and 3 at level 2). The nt-VAD group patients had significantly more preoperative mechanical circulatory support and were in a more critical condition before VAD implantation than the cf-VAD group. The 2-year survival rate was not significantly different. Despite the critical conditions of nt-VAD patients, their overall survival is not statistically inferior to that of cf-VAD patients. nt-VAD is a good option as a BTC for the patient with urgent and critical condition.  相似文献   
57.
Despite continual improvements in ventricular assist device (VAD) therapy, various clinical issues are emerging. Importantly, various types of thromboembolic complications have been reported to date. Recently, we encountered a rare continuous-flow VAD-related thromboembolic event that resulted in acute myocardial infarction. A 26-year-old female who just underwent HeartMate II® VAD implantation suddenly developed widespread anterolateral myocardial infarction on postoperative day 16. Echocardiography and aortography revealed a large thrombus on the left coronary cusp of the aortic valve that almost completely occluded the left coronary ostium. After VAD implantation, her aortic valve did not open, even at relatively low pump speeds; this was thought to be one of the causes for thrombus formation. Continuous suction of blood from the left ventricle and non-pulsatile flow into the ascending aorta resulted in a continuously closed aortic valve and stagnation of blood in the coronary cusp. Furthermore, both small body size (body surface area <1.3 m2) and postoperative right ventricular failure may have exacerbated blood stagnation and thrombus formation in this patient. We should have adjusted the anticoagulation and antiplatelet therapy protocols based on the patient’s condition. She underwent off-pump coronary artery bypass surgery and remained in clinically stable condition afterwards.  相似文献   
58.
The algorithm for the physiological control provided by left ventricular assist devices (LVADs) has been controversial. In particular, little is known about the physiological control algorithm (such as for achieving physiological circadian rhythms) in continuous-flow LVADs. To investigate the existence of circadian variation, we retrospectively evaluated the LVAD flow-correlated motor current of patients supported by continuous-flow LVADs. The motor current and the pump speed were collected from the external controller every 10 min after device implantation, and the data were divided for every 30-day period, which began on midnight on the first post-operative day. The subjects were 18 patients (mean age 37.7, mean body surface area 1.71 m2 at the time of operation) with dilated cardiomyopathy or dilated phase of hypertrophic cardiomyopathy. As of August 1, 2013, the patients’ median support duration was 889 days. The mean calculated dominant period of motor current variation was 24.0 h and the mean amplitude was 11.7 mA for the entire duration. The amplitude of the motor current circadian variation tended to be increased until around the fifth month. The motor current had a tendency to be relatively low during the night time and high during the day time. A significant difference was found between the night-time and day-time mean motor current for the entire duration (p < 0.05). In conclusion, the circadian variation of the motor current could be observed over long term in patients with fixed rotation speed continuous-flow LVAD support.  相似文献   
59.

Purpose

In the recent years in Japan, an increasing number of patients with neuroblastoma (NB) are being treated by the “delayed local treatment (DL)” policy, undergoing surgery after the completion of high-dose chemotherapy with hematopoietic stem cell rescue (HDC). We reviewed the histopathological findings of second-look operations, including those of patients treated with DL.

Patients

From 1998 to 2013, 26 patients with high-risk NB underwent radical operation following chemotherapy. Surgery was performed after induction chemotherapy in 17 cases (standard; STD), whereas 9 cases completed induction chemotherapy and HDC before undergoing tumor resection (DL). The amount of necrosis and the degree of differentiation within the post-treatment tumor were assessed.

Results

Eighty-eight percent of the tumors showed necrosis in more than 1/3 of the specimen. Two DL cases showed complete disappearance of viable tumor cells. Amount of necrosis did not affect the prognosis of the patient. Tumors with immature, poorly differentiated phenotypes showed an extremely aggressive thereafter. Though not statistically proven, 123I-MIBG (metaiodobenzylguanidine) uptake may be correlated with the amount of viable cells remaining within the tumor, but not with the degree of differentiation.

Conclusions

Our results support the previous reports advocating that tumors that sustain unfavorable histology after chemotherapy behave aggressively thereafter.  相似文献   
60.
Nanofiber vascular grafts have been shown to create neovessels made of autologous tissue, by in vivo scaffold biodegradation over time. However, many studies on graft materials and biodegradation have been conducted in vitro or in small animal models, instead of large animal models, which demonstrate different degradation profiles. In this study, we compared the degradation profiles of nanofiber vascular grafts in a rat model and a sheep model, while controlling for the type of graft material, the duration of implantation, fabrication method, type of circulation (arterial/venous), and type of surgery (interposition graft). We found that there was significantly less remaining scaffold (i.e., faster degradation) in nanofiber vascular grafts implanted in the sheep model compared with the rat model, in both the arterial and the venous circulations, at 6 months postimplantation. In addition, there was more extracellular matrix deposition, more elastin formation, more mature collagen, and no calcification in the sheep model compared with the rat model. In conclusion, studies comparing degradation of vascular grafts in large and small animal models remain limited. For clinical translation of nanofiber vascular grafts, it is important to understand these differences.  相似文献   
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