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91.
92.
Introduction
Breast cancer incidence increases from the age of 30 years. As this age range coincides with that in which women usually pursue pregnancy, undergoing medical examinations for conditions such as breast cancer is a concern, especially when pregnancy is uncertain during the first eight weeks. Moreover, in this age range, breast often exhibits a high density, thus compromising diagnosis. For such density, digital breast tomosynthesis (DBT) provides a more accurate diagnosis than 2D mammography given its higher sensitivity and specificity. However, radiation exposure increases during DBT, and it should be determined.Methods
We determined the entrance surface dose, scattered radiation dose, and average glandular dose (AGD), which can be mutually compared following an international protocol. Using our proposed method, the distribution of scattered radiation can be easily and quickly obtained with a minor load to the equipment. Then, we can determine the indoor scattered radiation and surface dose on patients during DBT.Results
We obtained a maximum AGD of 2.32 mGy. The scattered radiation was distributed over both sides with maximum of approximately 40 μGy, whereas the maximum dose around the eye was approximately 10 μGy.Conclusion
By measuring doses using the proposed method, a correct dose information can be provided for patients to mitigate their concerns about radiation exposure. Although the obtained doses were low, their proper management is still required. Overall, the results from this study can help to enhance dose management for patients and safety management regarding indoor radiation. 相似文献93.
Shiro Takei Yu Tokuhira Atsuyoshi Shimada Masanori Hosokawa Shin-Ichi Fukuoka 《Anatomical science international / Japanese Association of Anatomists》2010,85(4):245-250
We developed a novel method for enhancing light-microscopic visualization of pancreatic zymogen granules in a selective manner
on hematoxylin and eosin-stained sections. By using an absorption filter that transmits light with wavelength from 510 to
550 nm, corresponding to the narrow absorption spectrum of eosin, only eosinophilic tissue and cellular components were remarkably
highlighted as distinct shadows against lighter background consisting of basophilic components. Using a pair of mirror sections
of the pancreas, immunocytochemistry with anti-amylase antibody confirmed that the shadows observed through the filter represented
zymogen granules. Immersion in formalin for 36 h at room temperature was the optimal fixation condition. Here we designate
the procedure as the “eosin-shadow method” and propose that this technique is convenient and useful to help investigators
identify zymogen granules more easily in routine pathological examination and histological studies. 相似文献
94.
95.
Oide H Itatsu T Hirose M Wang XE Nishiyama D Takei Y Sato N 《Alcoholism, clinical and experimental research》2000,24(3):357-360
BACKGROUND: Hepatic stellate cells have been reported to play important roles in the regulation of hepatic microcirculation via cell contraction. Increase in intracellular calcium concentration is required to induce cell contraction. We have already reported the existence of L-type voltage-operated Ca2+ channels (VOCC), such as smooth muscle cells. On the other hand, alcohol has been known to disturb hepatic microcirculation. In this study, we evaluated the effect of acute and chronic treatment of alcohol on VOCC in rat hepatic stellate cells. METHODS: Stellate cells isolated from rats were cultured with or without 100 mM ethanol for up to 14 days. VOCC were detected by the patch clamp technique. Cells cultured for 14 days without ethanol were exposed to ethanol to investigate calcium current during membrane depolarization. alpha-Smooth muscle actin (alpha-SMA) was stained by indirect immunofluorescence. RESULTS: In the control model, VOCC were recognized in cells cultured for more than 7 days. Detection of VOCC increased from 9% on day 7 to 55% on day 14. On the other hand, VOCC in cells treated chronically with 100 mM ethanol appeared earlier than in the control and the incidences were significantly higher than those of the control accompanied with an early activation of cells. In contrast, simultaneous exposure to ethanol during the membrane depolarization inhibited Ca2+ current. CONCLUSIONS: The expression of Ca2+ channels in stellate cells were up-regulated by the chronic treatment of alcohol accompanied with the transformation to myofibroblast-like phenotype. However, alcohol itself inhibited Ca2+ current. 相似文献
96.
Current trends of sentinel lymph node biopsy for breast cancer--a surgeon's perspective. 总被引:1,自引:0,他引:1
Hiroyuki Takei Masafumi Kurosumi Takashi Yoshida Jun Ninomiya Yasutaka Hagiwara Mari Kamimura Yuji Hayashi Katsunori Tozuka Kimito Suemasu Kenichi Inoue Toshio Tabei 《Breast cancer (Tokyo, Japan)》2007,14(4):362-370
Sentinel lymph node biopsy (SLNB) is standard care for patients with early-stage breast cancer, and axillary lymph node dissection (ALND) is considered unnecessary when sentinel lymph nodes (SLNs) are tumor-free. Additional non-SLN metastasis in patients with positive SLNs can be estimated using several risk factors such as primary tumor size, metastatic tumor size in SLNs, lymphatic vessel invasion, and so on. All patients with positive SLNs may be treated with further ALND based on their own risk for non-SLN metastasis. Recent randomized clinical trials have already proved less surgical morbidity and better QOL for SLNB alone compared with ALND. However, trials concerning the efficacy of ALND in positive SLNB patients in preventing local regional recurrence and improving overall survival compared with no ALND, and also, concerning the effectiveness of ALND compared with axillary radiation therapy (RT), have not yielded clear results. The prognostic significance of micrometastasis in SLNs or bone marrow also remains to be determined. So far SLNB is not acceptable for patients with positive nodes in the axilla at initial diagnosis even if their axillary metastases are down-staged to negative by neoadjuvant chemotherapy. Although basically SLNB does not need to be performed for patients with pure ductal carcinoma in situ (DCIS), it is recommended for patients with an initial diagnosis of DCIS which is large, palpable, high grade, or found in younger patients. Because these types of DCIS have higher incidences of accompanying invasive lesions. In addition if patients will undergo mastectomy, SLNB is recommended because of the inability to perform SLNB after mastectomy. SLNB may be acceptable for patients with T3 or T4b tumors, even though SLN identification is lower yet SLN involvement is higher compared with T1 or T2 tumors, and systemic adjuvant therapy is more important for patients with T3 or T4b tumors. SLNB is a bridge to further axillary treatment such as ALND or axillary RT, and which strategy, including no further treatment, is best considered individually based on recurrence risk, treatment responsiveness and use or non-use of systemic therapy. 相似文献
97.
S Sato H Kitamura M Chino Y Takei M Hiruma M Nomura 《Food and chemical toxicology》2007,45(8):1537-1544
Gardenia yellow powders A, B and C, containing geniposide at 0.284%, 0.938% and 2.783%, respectively, were administered orally to male and female SD rats as 3% feed admixtures for 13-weeks to evaluate any potential toxicity. Mean geniposide intake values were 5.72, 18.9 and 56.3mg/kg/day in groups receiving these feed admixtures, respectively. All animals survived the duration of the study. The following findings were evident in the gardenia yellow C group: chromatouria, slightly increased plasma total bilirubin, blackish brown discoloration of the kidneys and liver, brown pigments in the proximal tubular epithelium of the kidneys. Slightly increased plasma total bilirubin was considered to be due to interference of metabolite of geniposide with the system of measurement and not to be a toxic effect since there were no related changes in histopathology of the liver or in any blood chemistry parameters. Other findings were limited to pigmentations or discolorations attributable to metabolites of geniposide. No treatment-related effects were evident on body weight, food consumption, ophthalmology, hematology or organ weights in any group. Therefore, it was concluded that 3-month ingestion of the gardenia yellow powder containing geniposide at 2.783% (approximately 60 mg/kg/day as geniposide intake) does not cause any severe toxic effects. 相似文献
98.
The in vitro activity of gatifloxacin was determined for 873 isolates from various infections during 1997-1998 in Japan. Gatifloxacin was active against streptococci, Escherichia coli, Klebsiella pneumoniae, Moraxella catarrhalis, Haemophilus influenzae and Neisseria gonorrhoeae, with MIC(90)s of =0.39 mg/L. The activity was two- to 32-fold greater than that of ciprofloxacin and levofloxacin against Gram-positive bacteria, and comparable to that against Gram-negative bacteria. Gatifloxacin was more active than the other quinolones against quinolone-resistant staphylococci, Enterococcus faecalis, E. coli and Enterobacter cloacae. It also had good activity against penicillin- or macrolide-resistant Streptococcus pneumoniae and ampicillin-resistant H. influenzae. 相似文献
99.
Yoshinami M Hamanaka T Kawano H Takahashi T Takei A Fukuchi I 《Japanese journal of ophthalmology》2000,44(5):576-577
Purpose: The methods of diagnosing neovascular glaucoma were evaluated in a case with carotid artery occlusive disease. A trabeculectomy specimen taken from this patient was examined histologically to find the characteristic picture of this slowly progressive neovascular glaucoma.Materials and Methods: The left eye of a 48-year old man with neovascular glaucoma due to carotid artery occlusive disease had been previously diagnosed as uveitis with ocular hypertension. His left eye was examined by fluorescein fundus and gonioangiography. Trabeculectomy was performed because of uncontrolled intraocular pressure and the trabeculectomy specimen was examined histologically including immunohistochemistry with antibodies against von Willebrand factor antigen.Results: The characteristic picture of fluorescein fundus angiography was filling delay in the choroid and stained walls of the retinal arteries and veins. Fluorescein gonioangiography using a fundus camera clearly demonstrated new vessels in the pupil and angle with intense fluorescein leak in spite of faint neovascularization in those areas when observed by slit lamp with gonioscopy. Histological examination of the trabeculectomy specimen revealed proliferation of new vessels in the spaces of the trabecular meshwork and focal occlusion of Schlemm's canal.Conclusion: Fluorescein fundus angiography and gonioangiography by fundus camera is very useful for diagnosis of neovascular glaucoma due to carotid artery occlusive disease. Neovascular proliferation in the trabecular meshwork with slight of peripheral anterior synechia and focal occlusion of Schlemm's canal may be peculiar to such slowly progressive neovascular glaucoma. 相似文献
100.