全文获取类型
收费全文 | 11897篇 |
免费 | 626篇 |
国内免费 | 47篇 |
专业分类
耳鼻咽喉 | 127篇 |
儿科学 | 356篇 |
妇产科学 | 115篇 |
基础医学 | 1540篇 |
口腔科学 | 400篇 |
临床医学 | 706篇 |
内科学 | 3106篇 |
皮肤病学 | 257篇 |
神经病学 | 936篇 |
特种医学 | 422篇 |
外科学 | 1859篇 |
综合类 | 62篇 |
一般理论 | 3篇 |
预防医学 | 435篇 |
眼科学 | 354篇 |
药学 | 771篇 |
中国医学 | 25篇 |
肿瘤学 | 1096篇 |
出版年
2023年 | 55篇 |
2022年 | 48篇 |
2021年 | 224篇 |
2020年 | 124篇 |
2019年 | 166篇 |
2018年 | 195篇 |
2017年 | 187篇 |
2016年 | 214篇 |
2015年 | 225篇 |
2014年 | 277篇 |
2013年 | 390篇 |
2012年 | 533篇 |
2011年 | 635篇 |
2010年 | 339篇 |
2009年 | 298篇 |
2008年 | 550篇 |
2007年 | 607篇 |
2006年 | 601篇 |
2005年 | 545篇 |
2004年 | 570篇 |
2003年 | 558篇 |
2002年 | 538篇 |
2001年 | 403篇 |
2000年 | 377篇 |
1999年 | 397篇 |
1998年 | 156篇 |
1997年 | 98篇 |
1996年 | 98篇 |
1995年 | 88篇 |
1994年 | 73篇 |
1993年 | 77篇 |
1992年 | 282篇 |
1991年 | 243篇 |
1990年 | 243篇 |
1989年 | 275篇 |
1988年 | 206篇 |
1987年 | 201篇 |
1986年 | 195篇 |
1985年 | 176篇 |
1984年 | 133篇 |
1983年 | 106篇 |
1982年 | 72篇 |
1981年 | 53篇 |
1979年 | 77篇 |
1978年 | 50篇 |
1977年 | 53篇 |
1975年 | 52篇 |
1973年 | 48篇 |
1971年 | 47篇 |
1969年 | 47篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
T Chishiro I Hara K Nakamura 《Rinsho byori. The Japanese journal of clinical pathology》1992,40(6):568-576
Using 655 peripheral blood samples from normal individuals and patients, we evaluated the relationship between the measurements of red blood cell (RBC) and white blood cell (WBC) through the Hematrak 590 (Hematrak) and the generated flag systems in the Technicon H-2 (H-2). 1) Among the 12 VAR (Variation) flag positive samples in H-2, 10 samples were obtained from the patients receiving blood transfusions. The samples with high values of HDW (Hemoglobin distribution width) in H-2 seemed to have hypochromatic and polychromatic changes in RBC. 2) Hematrak is likely to be more sensitive than H-2 in discovering atypical lymphocytes (AL). When AL counts in Hematrak were over 5 or 6% of WBC, these results were coincident with ATYP flag positive in H-2. 3) In our examinations, when %Blast in H-2 was over 4%, BLASTS flag always generated positively. We think that H-2 is a tool with high reproducibility for the detection of the blast-like abnormal cells. 4) We evaluated the results of WBC differential count by the three methods of H-2, Hematrak and manual procedures in the peripheral blood samples from normal individuals. We recognized close correlations in neutrophils, lymphocytes and eosinophils (coefficients of correlation = 0.826-0.911), and relatively close ones in monocytes (r = 0.280-0.562), but no correlations in basophils (r = 0.106-0.281). To comprehend the pathophysiological states of the various diseases hematologically, it is necessary to understand the characteristics of the different measurement principles between the two instruments (H-2 and Hematrak). 相似文献
53.
Kohji Nagata Michiko Horinouchi Miyuki Saitou Michiyo Higashi Mitsuharu Nomoto Masamichi Goto Suguru Yonezawa 《Journal of hepato-biliary-pancreatic sciences》2007,14(3):243-254
In this review article, we demonstrate the mucin expression profile in normal tissue, invasive ductal carcinoma (IDC), two subtypes of intraductal papillary–mucinous neoplasm (IPMN dark cell type and IPMN clear cell type), pancreatic intraepithelial neoplasia (PanIN), and mucinous cystic neoplasm (MCN) of the pancreas. In MUC1, there are various glycoforms, such as poorly glycosylated MUC1, sialylated MUC1, and fully glycosylated MUC1. IDCs showed high expression of all the glycoforms of MUC1. IPMNs dark cell type showed no expression or low expression of all the glycoforms of MUC1. IPMNs clear cell type showed low expression of poorly glycosylated MUC1, but expression of sialylated MUC1 and fully glycosylated MUC1. Expression of MUC2 was negative in IDCs, high in IPMNs dark cell type and low in IPMNs clear cell type. MUC5AC was highly expressed in IDCs, IPMNs dark cell type, and IPMNs clear cell type. MUC6 expression was higher in IPMNs clear cell type than in IDCs and IPMNs dark cell type. Our recent study demonstrated that high expression of MUC4 in IDCs is correlated with a poor outcome for patients. In PanINs, expression of both MUC5AC and MUC6 are an early event, whereas up-regulation of MUC1 is a late event. MCNs do not look as if they will show a specific mucin expression profile according to the literature review. 相似文献
54.
Yusuke Koizumi Hirozumi Obata Akinori Hara Takashi Nishimura Kenichiro Sakamoto Yoshihide Fujiyama 《World journal of gastroenterology : WJG》2007,13(3)
A 34-year-old female complaining of abdominal fullness was diagnosed as scirrhous gastric cancer (type 4')with peritonitis carcinomatosa in July 2002. A combined chemotherapy regimen was selected to control massive ascites; TS-1(R) 80 mg/m2 was given orally on d 1-14,22-35, and paclitaxel 50 mg/m2 was administered intravenously on d 1, 8, 22 and 29. After 2 courses of this regimen, the primary tumor was markedly reduced,and ascites completely vanished. Alopecia (grade 1,since d 30), leukocytopenia (grade 2, on d 34) and anemia (grade 2, on d 34) were the only adverse events throughout the following courses. The chemotherapy was effective for 28 mo, and then it was discontinued upon the patient's own request, and she survived for 36mo after diagnosis. 相似文献
55.
Takeshiro Fujii Yoshinori Watanabe Noritsugu Shiono Muneyasu Kawasaki Hiroki Yokomuro Tsukasa Ozawa Satoshi Hamada Hiroshi Masuhara Tetsuo Teramoto Masanori Hara Tomonori Katayanagi Yuki Sasaki Nobuya Koyama 《Annals of thoracic and cardiovascular surgery》2006,12(5):324-332
OBJECTIVE: To clarify the position of on-pump beating coronary artery bypass (CAB) and to define preoperative indicators of intentional conversion to the procedure in the era of advancement of off-pump CAB (OPCAB), we assessed on-pump beating CAB performed after the introduction of OPCAB. SUBJECTS AND METHODS: We assessed 130 patients who underwent single CAB [117 (90%) with OPCAB and 13 (10%) with on-pump beating CAB] between August 1999 (when OPCAB was selected as the first-line surgical procedure) and December 2004. RESULTS: No significant differences were seen between the groups in the number of coronary lesions or the prevalence of left main trunk (LMT) lesion. Reduced left cardiac function, cardiac dilatation, and mitral regurgitation (MR) were more remarkable in the on-pump beating CAB group. Preoperative ischemic condition was generally unstable in the both groups. A conversion to on-pump beating CAB occurred at anastomosis for the left anterior descending (LAD) branch in 61% and for the left circumflex (LCX) branch in 15%. LAD patients had more severe left cardiac dysfunction and cardiac dilatation than LCX patients. CONCLUSION: To perform safe and reliable CAB surgery, cardiovascular surgeons should define preoperative indicators of difficult OPCAB and convert OPCAB to on-pump beating CAB intentionally without hesitation when unstable hemodynamics is detected. 相似文献
56.
The response of periodontal nerves to experimentally induced occlusal trauma in rat molars was assessed by immunohistochemistry for protein gene product 9.5 (PGP 9.5) at light and electron microscopic levels, and by computerized image analysis. The occlusal surface on the left upper first molar of 8-wk-old male Wistar rats was raised approximately 1 min under ether anaesthesia. The rats were perfusion-fixed on d 1, 2, 3, 4, and 7 after bite-raising and then decalcified for 2–3 wk. Frozen sagittal cryostat sections were stained by the avidin-biotin complex method. By the second day after bite-raising many Ruffini endings were swollen and their outline unclear at the light microscopic level. Transmission electron microscopy disclosed PGP 9.5 reaction products within Ruffini endings that had unusually long cytoplasmic projections extending through enlarged slits of the Schwann sheaths and also diffuse extracellular PGP 9.5-immunoreactivity near the Ruffini endings. From d 2 to 4, thin nerve fibres on the pressure side of the periodontal ligament were orientated irregularly and had a prominent beaded appearance. An increase in beaded nerve terminals occurred at d 2–4 post elevation, and decreased later. These results suggest that occlusal trauma induces specific changes in the distribution and shape of nerve terminals in the periodontal ligament. 相似文献
57.
Immunoreactive opsin and glial fibrillary acidic protein in persistent hyperplastic primary vitreous
An 8-month-old boy had an anterior type of persistent hyperplastic primary vitreous in the right eye. Results of needle biopsy, performed because of elevated intraocular pressure, disclosed clusters of blastic cells. The eye was enucleated on the suspicion of retinoblastoma. Histological examination showed retrolental fibrovascular tissue and retinal dysplasia. Immunoreactive opsin was detected in the innermost structures and in photoreceptor-like cells of rosettes. We conclude that photoreceptor cells differentiated to express opsin, even when neighbouring cells were abnormally arranged. An immunocytochemical study of glial fibrillary acidic protein demonstrated glial proliferation in the inner layer of the retina but not in the preretinal space. 相似文献
58.
Masami Yoshida Hideyasu Yokoo Kimihiro Nakahara Masaru Tomita Naoyuki Hamada Michiko Ishikawa Jyunko Hatakeyama Masatoshi Tanaka Ikuko Nagatsu 《Brain research》1997,767(2):87
Infusion of muscimol (5×10−5 M, 60 min) into the nucleus accumbens (NAC) through a dialysis membrane caused a significant increase in extracellular dopamine (DA) and its metabolite, 3,4-dihydroxyphenylacetic acid (DOPAC). Fos-like immunoreactivity induced by intra-NAC infusion of muscimol was seen ipsilaterally in many accumbofugal target areas, but no Fos-positive neurons were seen in the vicinity of the dialysis membrane in the NAC. Sequential staining of Fos and tyrosine hydroxylase (TH) immunoreactivities revealed that a portion of A10 dopaminergic neurons were double-labelled. These results suggest that muscimol in the NAC disinhibits mesolimbic DA neuronal activity possibly through activity of the accumbofugal GABA neuron system. 相似文献
59.
S Kubo A Yasuoka T Rikitake T Shimoda K Fujita M Nakatomi K Hara 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(9):1161-1167
The authors examined pulmonary hemodynamics with respect to underlying diseases, severity and type of chronic respiratory failure, and the incidence and effect of home oxygen therapy (HOT) in 155 patients with chronic lung diseases (old pulmonary tuberculosis (OTB) 45, chronic pulmonary emphysema (CPE) 54, chronic bronchitis (CBR) 42 and fibrosing lung disease (FLD) 14). They underwent right heart catheterization during a stable period, while breathing room air. The arterial PO2 ranged from 64.3 +/- 9.7 Torr (CBR) to 69.9 +/- 10.0 Torr (CPE), and the mean pulmonary arterial pressure ranged from 17.3 +/- 4.6 mmHg (CPE) to 20.6 +/- 5.4 mmHg (OTB). The incidence of pulmonary hypertension (PH, PA mean greater than or equal to 20 mmHg) was 53.3% in OTB, 40% in CBR, 35.7% in FLD, 23.8% in CPE, 69% in respiratory failure, 40% in quasi-respiratory failure, and 2.1% in non-respiratory failure. The percentage of patients who received HOT was 84.5% in respiratory failure and 54.1% in quasi-respiratory failure. Comparing Type I with Type II chronic respiratory failure, the incidence of PH was lower in the former than the latter (38.3% vs 80.6%), whereas HOT was applied to an equal percentage of patients (67.4%) in both groups. The effect of HOT was evaluated in 11 patients with chronic respiratory failure. The mean pulmonary arterial pressure was 22.7 +/- 4.7 mmHg before HOT, and decreased to 20.7 +/- 5.6 mmHg after 24.5 +/- 10.1 months of HOT. Although this difference was not significant statistically, this result suggests the desirable effect of HOT on pulmonary hemodynamics. 相似文献
60.
Michiko Kawaguchi Masaaki Techigawara Takako Ishihata Tsukasa Asakura Fujiko Saito Kazuhira Maehara Yukio Maruyama 《Heart and vessels》1997,12(6):267-274
Summary The pathogenesis of diabetic cardiomyopathy is unknown. The synergistic, or enhanced, effect of hypertension on pathological
changes in the heart of diabetic patients has been highly suspected. The purpose of this study was to evaluate the myocardial
changes related to diabetes mellitus with and without hypertension, using biopsy specimens. We examined the ultrastructural
changes in biopsy specimens of the endomyocardium obtained from 25 patients. They were divided into four groups: controls
without hypertension or diabetes mellitus (n=6), and patient with hypertension (n=3), diabetes mellitus (n=8), and diabetes with hypertension (n=8). The diabetic patients showed nearly normal or mildly depressed systolic left ventricular function. Ultrastructural pictures
were analyzed for thickening of the capillary basement membrane, presence of toluidine blue-positive materials (i.e., materials
showing metachromasia) in the myocytes, size of myocytes, and interstitial fibrosis. The thickening of the capillary basement
membrane, the accumulation of toluidine blue-positive materials, and interstitial fibrosis were all significantly greater
in the patients with diabetes mellitus compared to the control subjects. The myocytes tended to be small (cell atrophy) in
the diabetes group. Although these pathological changes in the heart were characteristic of diabetic patients, irrespective
of the presence or absence of hypertension, the presence of hypertension increased the pathological changes of myocardial
cells as well as abnormality in the capillary vessels in patients with diabetes mellitus. Alterations in the myocardial cells
and capillaries, caused by diabetes mellitus, may lead to myocardial cell injury and interstitial fibrosis and, ultimately,
to ventricular systolic and diastolic dysfunction, especially when the diabetes is accompanied by hypertension. 相似文献