全文获取类型
收费全文 | 9273篇 |
免费 | 436篇 |
国内免费 | 50篇 |
专业分类
耳鼻咽喉 | 133篇 |
儿科学 | 159篇 |
妇产科学 | 181篇 |
基础医学 | 1112篇 |
口腔科学 | 304篇 |
临床医学 | 536篇 |
内科学 | 2393篇 |
皮肤病学 | 135篇 |
神经病学 | 704篇 |
特种医学 | 395篇 |
外科学 | 1375篇 |
综合类 | 49篇 |
预防医学 | 252篇 |
眼科学 | 138篇 |
药学 | 644篇 |
中国医学 | 26篇 |
肿瘤学 | 1223篇 |
出版年
2023年 | 56篇 |
2022年 | 122篇 |
2021年 | 163篇 |
2020年 | 107篇 |
2019年 | 124篇 |
2018年 | 168篇 |
2017年 | 129篇 |
2016年 | 167篇 |
2015年 | 180篇 |
2014年 | 252篇 |
2013年 | 293篇 |
2012年 | 506篇 |
2011年 | 533篇 |
2010年 | 318篇 |
2009年 | 293篇 |
2008年 | 499篇 |
2007年 | 499篇 |
2006年 | 495篇 |
2005年 | 526篇 |
2004年 | 497篇 |
2003年 | 452篇 |
2002年 | 489篇 |
2001年 | 250篇 |
2000年 | 245篇 |
1999年 | 229篇 |
1998年 | 139篇 |
1997年 | 123篇 |
1996年 | 119篇 |
1995年 | 80篇 |
1994年 | 88篇 |
1993年 | 77篇 |
1992年 | 171篇 |
1991年 | 155篇 |
1990年 | 131篇 |
1989年 | 134篇 |
1988年 | 100篇 |
1987年 | 84篇 |
1986年 | 87篇 |
1985年 | 82篇 |
1984年 | 71篇 |
1983年 | 59篇 |
1982年 | 29篇 |
1980年 | 30篇 |
1979年 | 52篇 |
1978年 | 30篇 |
1977年 | 38篇 |
1976年 | 27篇 |
1974年 | 24篇 |
1969年 | 24篇 |
1967年 | 24篇 |
排序方式: 共有9759条查询结果,搜索用时 31 毫秒
101.
Acquired gain of an X chromosome as the sole abnormality in the blast crisis of chronic neutrophilic leukemia 总被引:2,自引:0,他引:2
Chronic neutrophilic leukemia (CNL) is a rare myeloproliferative disorder characterized by sustained neutrophilic leukocytosis and absence of the Philadelphia chromosome. Most patients with CNL have normal karyotypes, and no specific cytogenetic abnormality has been identified. We report here a patient with CNL that evolved to myeloid blast crisis. A 73-year-old man was admitted to the hospital because of marked leukocytosis (leukocyte count 112.5 x 10(9)/L with 91% segmented neutrophils) and massive hepatosplenomegaly that was diagnosed as CNL with a normal karyotype. After treatment with hydroxyurea for 7 months, the disease progressed to a blast crisis. Bone marrow showed myeloid hyperplasia with 21% myeloblasts, 15% promyelocytes, and marked dysplastic changes of neutrophils. Blastic cells were positive for CD10, CD13, CD14, CD33, CD34, and HLA-DR. Chromosome analysis of the bone marrow cells showed 46,XY,+X in all 20 metaphase spreads. We reviewed 15 cases of CNL terminating in the blast crisis and confirmed that all cases transformed into myeloid crises and had poor prognoses. Furthermore, to our knowledge, this is the first case showing the acquired gain of an extra X chromosome as a sole abnormality in CNL. The gain of an extra X chromosome may play an important role in the progression from chronic phase to the blast crisis of CNL. 相似文献
102.
Cisplatin-induced long-term dynorphin A-immunoreactivity in cell somata of rat area postrema neurons
Goichi Tsukamoto Hiroyuki Ichikawa Motoi Kobashi Yosuke Yamada Takeshi Kikuchi Hiroshi Mese Akira Sasaki 《Neuroscience letters》2007
We evaluated long-term dynorphin A-immunoreactivity in the rat area postrema (AP) after the administration of cisplatin. First, rats were given 1, 5 and 10 mg/kg body weight cisplatin (i.p.) and their behavior was monitored for 72 h. We observed a delayed increase in pica 24-72 h after injection, compared to the 24 h before injection. We attributed this to the cisplatin injection. Pica was defined as an increase in the intake of non-nutritional matter such as kaolin. Administration of 1, 5 and 10 mg/kg cisplatin led to an increase in kaolin intake on day 1. Administration of 5 and 10 mg/kg of cisplatin led to decreased intake of laboratory chow (MF) on days 1–3, but 10 mg/kg cisplatin causes an excessive aggravation of their condition. Following this behavioral experiment, we immunohistochemically examined the induction of dynorphin A in the AP at 24, 48 and 72 h post-administration of 1 and 5 mg/kg cisplatin. Administration of 5 mg/kg cisplatin caused dynorphin A to accumulate gradually in the neurosoma of the AP neurons, and the numbers of positive AP neurosomata at 48 and 72 h post-administration were higher than following an equal dosage of 0.9% NaCl. These findings suggest that dynorphin A increases in the central nervous system for a long time following administration, and causes certain behavioral and clinical changes, including those related to appetite and nausea. 相似文献
103.
Gastrointestinal graft-versus-host disease in recipients of autologous hematopoietic stem cells: incidence, risk factors, and outcome. 总被引:2,自引:0,他引:2
Leona Holmberg Kaoru Kikuchi Ted A Gooley Kristina M Adams David M Hockenbery Mary E D Flowers H Gary Schoch William Bensinger George B McDonald 《Biology of blood and marrow transplantation》2006,12(2):226-234
Graft-versus-host disease (GVHD) is seen in skin, intestinal mucosa, and liver after autologous stem cell transplantation. We reviewed 681 consecutive patients to estimate the probability of gastrointestinal (GI) GVHD, response to treatment, risk factors for development, and effect on survival. GI GVHD was defined by persistent symptoms, mucosal abnormalities at endoscopy, and histology showing apoptotic crypt cells with or without lymphoid infiltrates. The proportion of patients with GI GVHD was 90/681 (13%). Nausea and vomiting occurred in 90% and diarrhea in 40%. The mean time to developing symptoms was day +15, that to histologically proven diagnosis was day +42, and that to starting prednisone treatment was day +45 after stem cell infusion. Treatment with a short course of prednisone effected durable responses in 79% of patients, and an additional 18% responded to a second course of prednisone. A multivariable logistic regression model demonstrated that the combined factor of a diagnosis of breast cancer or hematologic malignancy and female sex was statistically significantly associated with the probability of GI GVHD (P = .003). Survival in patients with GI GVHD was not statistically different than that in those without GVHD. We conclude that women with breast cancer or hematologic malignancy are more likely to develop GI GVHD after autologous transplantation, and that treatment with prednisone was effective. 相似文献
104.
HLA class II haplotypes associated with pulmonary interstitial lesions of polymyositis/dermatomyositis in Japanese patients 总被引:2,自引:0,他引:2
Horiki T Ichikawa Y Moriuchi J Hoshina Y Yamada C Wakabayashi T Jackson K Inoko H 《Tissue antigens》2002,59(1):25-30
To elucidate the immunogenetic background of idiopathic inflammatory myopathies (IIM) such as polymyositis (PM), dermatomyositis (DM) and any overlapping subsets, with other collagen vascular diseases, HLA class I antigens and class II alleles were determined and compared from individuals with various clinical and serological features of IIM, including pulmonary interstitial lesions (PI). Seventy-three Japanese patients with myositis (32 PM, 18 DM, 23 overlapped subsets) and 62 healthy unrelated controls were enrolled onto the study. Statistical differences between groups were determined by the Fisher's exact probability test. Serum fluorescent antinuclear antibody, rheumatoid factor (RF), anti-SS-A/Ro antibody, anti-Jo1 antibody and anti-U1 RNP antibody were examined using routine methods. PI was detected by chest X-ray and/or computed tomography. In patients with DM, the frequency of the HLA-DRB1*1302-DQA1*0102-DQB1*0604 haplotype was significantly higher than in the healthy controls (42.1% vs 17.7%), and in the patients with PM (42.1% vs 9.4%). Furthermore, the frequency of the HLA-DRB1*0405-DQA1*03-DQB1*0401 haplotype was higher in the PM patients with PI than in the controls (50.0% vs 17.7%), and PM without PI (50.0% vs 5.5%). These results suggest that in terms of HLA class II association, Japanese DM and PM, and PM with and without PI, belong to different clinical groups. 相似文献
105.
J chain-positive cells in bursectomized chicks 总被引:1,自引:0,他引:1
Using embryonic chickens treated with testosterone propionate, the effects of congenital absence of the bursa of Fabricius determined by the frequency of J chain-positive cells was examined in the spleen, thymus and bone marrow at the embryonic and newly hatched stages. J chain-positive cells in the chicks without bursa were reduced in the spleen. No differences in the numbers of the cells were detected in the thymus and bone marrow. These results imply that removal of the bursa of Fabricius cannot entirely prevent the generation of J chain-positive B cells. Furthermore, these results partly suggest the important role of the bone marrow in the proliferation of some J chain-positive cells in chicks without bursa. 相似文献
106.
Toshihiko Sato Kaoru Abe Akira Kurose Noriyuku Uesugi Takeshi Todorokl and Kohsuke Sasakl 《Pathology international》1997,47(2-3):179-182
The amplification and overexpression of the c- erbB -2 gene are considered to be Implicated In the process of carcincogenesis of a variety of human tumors. The amplification and overexpression of c- erbB -2 were investigated in 48 surgically resected human gastric cancers by means of fluorescence In situ hybridization and immunohistochemistry. DNA ploidy was determined by flow cytometry. The c- erbB -2 amplification was demonstrated as a cluster of signals, suggesting homogeneously staining region (HSR), in three tumors (6.3%) accompanied by the overexpression of its protein. Such overexpression was detected In another tumor without amplification of the c- erbB -2 gene. All tumors with amplification and overexpression of c- erbB -2 were differentiated adenocarcinoma histologically, but only 10.3 and 13.8% of differentiated carcinomas showed amplification and over-expression of the c- erbB -2 gene, respectively. There was no relationship between the amplification and overexpression of c- erbB -2 and the depth of tumor invaslon and lymph node Involvement. Three of four cases with overexpression of c- erbB -2 were classified Into DNA aneupldd tumor. 相似文献
107.
108.
Immunohistochemical,ultrastructural and biochemical studies of an amylase-producing breast carcinoma
Hideo Inaji Hiroki Koyama Masahiko Higashiyama Shinzaburo Noguchi Hitoshi Yamamoto Osamu Ishikawa Kaoru Omichi Takeshi Iwanaga Akira Wada 《Virchows Archiv : an international journal of pathology》1991,419(1):29-33
Summary We describe a breast cancer with ectopic production of amylase, found in the patient's serum, urine and in the tumour. Clinically, serum amylase levels reflected both the progression of the disease and regression induced by various therapies. Using agarose gel electrophoresis and a wheat protein inhibitor assay, the predominant serum amylase appeared to be identical to pancreatic-type isoenzyme. However, the action mode analysis using a new fluorogenic substrate revealed that the serum contained non-salivary, non-pancreatic amylase. The tumour had microscopic features of invasive ductal carcinoma with some argyrophilic differentiation. The component cells stained positively for amylase, and ultrastructurally numerous secretory granules were seen. 相似文献
109.
Akishi Ooi Toru Kameya Masaru Tsumuraya Ken Yamaguchi Kaoru Abe Yukio Shimosato Noboru Yanaihara 《Virchows Archiv : an international journal of pathology》1985,405(3):311-323
Summary Nine pancreatic endocrine tumours of patients with watery diarrhoea hypokalaemia achlorhydria (WDHA) syndrome were examined by immunohistochemistry and electron microscopy. All cases revealed neoplastic proliferation of VIP (vasoactive intestinal peptide)-immunoreactive (IR) cells. Immunoreactivity to a novel peptide hormone PHM-27, which is processed from a common big precursor peptide of VIP (prepro VIP/PHM-27), was identified in VIP-IR cells of 8 tumours. VIP-PHM-IR cells had secretory granules measuring about 130 to 220 nm in diameter. Radioimmunoassay of tumour tissue extracts showed high VIP and PHM contents in proportional amounts in most cases. According to the results of immunostaining, the 8 tumours fell into two large groups; 5 with PP (pancreatic polypeptide)-IR cells and 3 with CT (calcitonin)-IR cells. The former group demonstrated VIP cells and PP cells intermingled in various proportions, including one tumour in which coexistence of PP-IR and VIP-IR in the same cells was demonstrated. Cell heterogeneity of the tumours and possible relationships of VIP, PP and CT cells were discussed.This work was supported in part by Grants-in-Aid for Cancer Research from the Ministry of Health and Welfare and from the Ministry of Education, Science and Culture, Japan 相似文献
110.
Continuous estimation of systolic blood pressure using the pulse arrival time and intermittent calibration 总被引:8,自引:0,他引:8
Chen W Kobayashi T Ichikawa S Takeuchi Y Togawa T 《Medical & biological engineering & computing》2000,38(5):569-574
A continuous noninvasive method of systolic blood pressure estimation is described. Systolic blood pressure is estimated by
combining two separately obtained components: a higher frequency component obtained by extracting a specific frequency band
of pulse arrival time and a lower frequency component obtained from the intermittently acquired systolic blood pressure measurements
with an auscultatory or oscillometric system. The pulse arrival time was determined by the time interval from QRS apex in
electrocardiogram to the onset of photoplethysmogram in a fingertip beat-by-beat via an oximetric sensor. The method was examined
in 20 patients during cardiovascular surgery. The estimated values of systolic blood pressure were compared with those measured
invasively using a radial arterial catheter. The results showed that the correlation coefficients between estimated values
and invasively obtained systolic blood pressure reached 0.97±0.02 (mean±SD), and the error remained within ±10% in 97.8% of
the monitoring period. By using a system with automatic cuff inflation and deflation to acquire intermittent systolic blood
pressure values, this method can be applicable for the continuous noninvasive monitoring of systolic blood pressure. 相似文献