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51.
Matsumoto A Tanaka E Morita S Yoshizawa K Umemura T Joshita S 《Journal of gastroenterology》2012,47(9):1006-1013
Background
Despite its status as a potential biomarker of hepatitis B virus (HBV) response to interferon treatment, the changes in hepatitis B surface antigen (HBsAg) levels over the natural course of HBV carriers have not been analyzed sufficiently.Methods
A total of 101 HBV carriers were followed prospectively from 1999 to 2009. HBsAg level was measured yearly during the followed period.Results
HBsAg levels at baseline ranged from ?1.4 to 5.32 log IU/ml, with a median value of 3.2 log IU/ml. Lower HBsAg levels were significantly associated with higher age and lower HBV replication status. The rate of change of HBsAg levels showed two peaks, with a cut-off value of ?0.4 log IU/year. Based on this, patients were tentatively classified into rapid decrease (rate of change 0.4 log IU/year) and non-rapid decrease groups. All baseline levels of HBsAg, HB core-related Ag, and HBV DNA were lower in the rapid decrease group than in the non-rapid decrease group. Patients with persistently positive HBeAg were all classified into the non-rapid decrease group. In patients with persistently negative HBeAg, HBV DNA levels were significantly (P?=?0.028) lower in the rapid decrease group than in the non-rapid decrease group.Conclusions
Lower baseline HBsAg levels were significantly associated with older age and lower viral activity. Both a loss of HBeAg detection as well as inactive replication of HBV are suggested to be fundamental factors contributing to a rapid decrease in HBsAg over the natural course of HBV infection. 相似文献52.
Yoshikawa T Hara T Araki H Tsurumi H Oyama M Moriwaki H 《International journal of hematology》2012,95(6):689-691
Deferasirox is a new oral iron chelator used to treat transfusional iron overload. We describe a case of a 79-year-old man with myelodysplastic syndrome (MDS) who developed esophagitis induced by deferasirox. He repeatedly received multiple red blood cell transfusions after a diagnosis of MDS. Two years after starting red blood cell transfusions, he was diagnosed with iron overload, and was then started on deferasirox at 1 g/day with about 400 ml of water. He was admitted to our institution because he was unable to swallow his own saliva 1 month after starting deferasirox. Esophagogastroendoscopy revealed white-coated mucosa covering the entire esophagus. A component analysis of biopsy specimens using high-performance liquid chromatography identified deferasirox. Symptoms resolved within about 2 weeks after discontinuing deferasirox, and repeated endoscopy showed marked improvement of esophagitis after 1 month. Re-administration of deferasirox was not attempted. Unfortunately, the patient died due to pneumonia 6 months after administration of deferasirox was started. This is the first report of drug-induced esophagitis associated with deferasirox. 相似文献
53.
Senji Kasahara Hisashi Tsurumi Yuhei Shibata Takuro Matsumoto Nobuhiko Nakamura Hiroshi Nakamura Nobuhiro Kanemura Naoe Goto Takeshi Hara Hisataka Moriwaki 《International journal of hematology》2012,96(5):674-678
We describe two patients with T cell prolymphocytic leukemia (T-PLL) who exhibited the same complex karyotype, including an additional segment at 1p36.1. One presented with secondary progression following an initial stable clinical course, and the other with typically progressive disease. Features of the cerebriform variant were identified in the peripheral blood of both patients. Aggressive symptoms, such as lymphocytosis, lymphadenopathy, pleural effusion, cutaneous involvement and hepatosplenomegaly, developed during the progressive phases. Levels of serum soluble interleukin 2 receptor increased when symptoms worsened. These patients did not have the karyotypic 14q11 abnormality and trisomy 8q that are features of non-Japanese patients. The prognoses of these patients were poor; one survived for 2 months and the other survived for 10 months after progression. A chromosomal abnormality may occur in other types of aggressive T-PLL, particularly when extramedullary infiltration is a feature. 相似文献
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57.
Taro Ohba Gouji Toyokawa Takuro Kometani Kaname Nosaki Fumihiko Hirai Masafumi Yamaguchi Motoharu Hamatake Takashi Seto Yukito Ichinose Kenji Sugio 《Surgery today》2014,44(3):478-486
Purpose
This study retrospectively assessed the mutations of the epidermal growth factor receptor (EGFR) and K-ras genes and their clinical significance in patients with resected stage I adenocarcinomas.Methods
A total of 354 patients with resected lung adenocarcinomas were included, and 256 patients with stage I disease were analyzed for the prognostic and predictive value of these mutations.Results
Mutations of EGFR and K-ras genes were detected in 149 (41.1 %) and 23 (6.4 %) of all tumors, and in 122 (47.6 %) and 14 (5.5 %) of stage I tumors, respectively. There were no significant differences in the disease-free survival (DFS) and overall survival (OS) between the EGFR-mutant and wild-type groups. However, the DFS and OS were significantly shorter in patients with K-ras mutations than in those without (5-year DFS: 50.8 vs. 76.9 %, 5-year OS: 70.0 vs. 86.6 %, p < 0.01). A multivariate analysis showed that K-ras mutations were an independent poor prognostic factor. Twenty-four of the 41 patients with recurrent disease after surgery were treated with an EGFR–TKI. Fifteen EGFR-mutant patients treated with an EGFR–TKI had a better prognosis than did the nine EGFR-wild-type patients.Conclusion
The presence of an EGFR gene mutation was a predictive factor for the response to EGFR–TKI treatment in patients with resected stage I adenocarcinoma, but was not a prognostic factor. The presence of a K-ras gene mutation was a poor prognostic factor. 相似文献58.
Toshihiro Sawai Masaomi Nangaku Akira Ashida Rika Fujimaru Hiroshi Hataya Yoshihiko Hidaka Shinya Kaname Hirokazu Okada Waichi Sato Takashi Yasuda Yoko Yoshida Yoshihiro Fujimura Motoshi Hattori Shoji Kagami 《Clinical and experimental nephrology》2014,18(1):4-9
Atypical hemolytic uremic syndrome (aHUS) is rare and comprises the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury. Recently, abnormalities in the mechanisms underlying complement regulation have been focused upon as causes of aHUS. The prognosis for patients who present with aHUS is very poor, with the first aHUS attack being associated with a mortality rate of ~25 %, and with ~50 % of cases resulting in end-stage renal disease requiring dialysis. If treatment is delayed, there is a high risk of this syndrome progressing to renal failure. Therefore, we have developed diagnostic criteria for aHUS to enable its early diagnosis and to facilitate the timely initiation of appropriate treatment. We hope these diagnostic criteria will be disseminated to as many clinicians as possible and that they will be used widely. 相似文献
59.
Kaname Okura Kazunari Miyazaki Hiroki Muroyama Toshiaki Matsui Koichi Eguchi 《RSC advances》2018,8(56):32102
Ammonia decomposition has attracted increasing attention as a promising process for the on-site generation of hydrogen. In this study, Ni catalysts supported on perovskite-type oxides (ABO3) were prepared and the activity for ammonia decomposition was examined. The Ni/ANbO3 (A = Na and K) and Ni/AEMnO3 (AE = Ca, Sr, and Ba) catalysts were less effective for this reaction. Meanwhile, the Ni/REAlO3 (RE = La, Sm, and Gd) catalysts exhibited relatively high activity. For Ni/AETiO3 and Ni/AEZrO3, the performance strongly depended on the A-site element of the perovskite-type oxides, and the Sr and Ba elements were more effective than the Ca one in the respective series. The catalytic activity for Ni/AEZrO3 was higher than Ni/AETiO3 in the case of the same alkaline earth element, and Ni/BaZrO3 was the most active among the samples investigated in this work. For these series, the order in the performance corresponded well with that in the basic property. The nitrogen desorption profiles revealed that the evolution of nitrogen atoms, which is one of the kinetically slow steps, effectively proceeded for Ni/SrZrO3 and Ni/BaZrO3 compared with the conventional Ni catalysts. This promotion effect would be ascribed to the strong basic properties of the SrZrO3 and BaZrO3 supports, resulting in the high activity of Ni/SrZrO3 and Ni/BaZrO3 for ammonia decomposition.Ni/SrZrO3 and Ni/BaZrO3 catalysts showed high activity for ammonia decomposition since these supports promoted the nitrogen desorption step. 相似文献
60.
K Hasegawa K Moriwaki T Igarashi T Sugase F Kawakami Y Itoh M Nishikawa 《Nippon Naibunpi Gakkai zasshi》1975,51(9):749-759
Six cases of Cushing's syndrome with adrenocortical tumors which showed a variety of responsiveness to ACTH were investigated in relation to their clinical pictures and laboratory findings. Abnormal responses to ACTH in tumors was analyzed by in vitro experiments with surgically obtained tumor tissues, and the ACTH responsive mechanism of the tumors was discussed. An 8 hour intravenous ACTH infusion test showed that three of these patients were ACTH responsive, and the other three unresponsive. Histological observation of the tumors revealed that ACTH responsive tumors were adenomas and that ACTH unresponsive tumors were "black adenomas" in two and a carcinoma in one. To investigate possible factors which might account for these differences in ACTH responsiveness, tumor specimens of each one of the responsive and unresponsive adenomas, and a carcinoma were subjected to in vitro studies. When incubated with ACTH or cyclic AMP, tissue sections of a responsive adenoma enhanced cortisol secretion, while that of a black adenoma failed to show any change. Steroidogenesis by carcinoma sections were significantly suppressed in the presence of ACTH or cyclic AMP. Cycloheximide abolished a stimulatory effect of ACTH and cyclic AMP on steroidogenesis in a responsive adenoma without affecting its basal secretion of cortisol. Steroidogenesis by unresponsive tumors (an adenoma and a carcinoma) were decreased by cycloheximide. Since the conversion of cholesterol to pregnenolone, the rate limiting step in steroidogenesis, takes place in adrenal mitochondria, the effect of cyclic AMP on pregnenolone formation from 14C-cholesterol by mitochondrial fractions of these tumors was examined. Cyclic AMP stimulated pregnenolone formation by mitochondrial fraction of an ACTH responsive adenoma, while with that of an unresponsive adenoma pregnenolone formation was not affected. Pregnenolone formation by cancer mitochondria was significantly suppressed by cyclic AMP. These results suggest that the unresponsiveness to ACTH of these tumors might be explained by the ineffectiveness of cyclic AMP to stimulate pregnenolone formation by tumor mitochondria, and that the steroidogenic pathway in unresponsive tumors are in an enhanced state even without cyclic AMP. It should be mentioned that all unresponsive adenomas gave a characteristic appearance of a "black adenoma". Histologically, tumors were composed of compact cells with abundant lipofuscin granules. The possible relationship between the ACTH responsiveness of adrenocortical tumors and some clinical pictures caused by them was also noticed. ACTH unresponsive adenomas resulted in shorter duration, severer conditions of the disease and higher 17-ketosteroid excretion than responsive adenomas. The growth of unresponsive tumors seemed faster than that of responsive ones. 相似文献