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41.
In the medical field, Korotkoff sounds have been explained as sounds generated by the disturbed blood flow in the artery. However, in the biomechanics field, Korotkoff sounds are considered to be produced and/or modified by the self-excited oscillation of a collapsed artery. The self-excited oscillation is an oscillation of the arterial wall. In addition, it is influenced by the nonlinear pressure–flow relationships in the artery and the arterial compliance. In this paper, we proposed an arterial-compliance-measuring method, using Korotkoff sounds. We constructed a circulatory simulator with a brachial model that mimics the physiological circulation, because in vivo resolution of nonlinear pressure–flow relationships is very difficult. The simulator was utilized to generate artificial Korotkoff sounds similar to those in auscultation in the brachial model. Additionally, we prepared latex tubes as artificial brachial arteries. In the experiment, we investigated the relationship between the self-excited oscillation and Korotkoff sounds by the distinguishing its frequency characteristics. The frequency of the sounds was changed by the variation of the tube compliance. As a result, we have found that the changes of the sounds largely depended on the difference of the tube compliance in this simulator. In conclusion, Korotkoff sounds contain useful information for predicting brachial arterial compliance. These experiments indicate the effectiveness of noninvasive measurement for brachial arterial compliance using Korotkoff sounds. 相似文献
42.
Toshifumi Gabata Osamu Matsui Masumi Kadoya Jun Yoshikawa Kazuhiko Ueda Yasuhiro Kawamori Tsutomu Takashima 《Journal of magnetic resonance imaging : JMRI》1997,7(5):855-857
The purpose of this study was to determine the relationship between segmental hyperintensity of the liver on T1-weighted images and segmental cholestasis in patients with obstructive jaundice. T1-weighted and T2-weighted MR images were obtained of 73 patients with obstructive jaundice caused by various diseases. Fat-suppressed T1-weighted images were also obtained of 10 patients. Eleven patients with segmental intra-hepatic bile duct dilatation (cholestasis) showed segmental hyperintensity on T1-weighted images and/or fat-suppressed T1-weighted images and no signal intensity difference on T2-weighted images. Sixty-two patients with widespread intrahepatic bile duct dilatation showed no intensity difference on T1-weighted and T2-weighted images (P < .01). Segmental hyperintensity on T1-weighted images was correlated with intrahepatic cholestasis. 相似文献
43.
Atsuhiro Yoshida Asami Takeda Katsushi Koyama Yasuhiro Ohtsuka Kunio Morozumi Tadashi Oikawa 《Clinical and experimental nephrology》1997,1(4):292-296
Kimura's disease is a rare disorder that involves regional lymph nodes and the major salivary glands, which become infiltrated
by eosinophils and lymphocytes. Renal lesions associated with Kimura's disease are rare. We describe the case of a 60-year-old
Japanese woman who first noted a nodular mass in a salivary gland. As the nodule grew, nephrotic syndrome and heart failure
developed. A biopsy of the nodule revealed Kimura's disease, and surgical excision was performed. After the operation, the
heart failure and nephrotic syndrome, which were diagnosed as minimal change disease on renal biopsy, improved rapidly without
steroid therapy. Four months later, the nephrotic syndrome recurred without recurrence of Kimura's disease. The patient showed
marked improvement during prednisolone therapy (40 mg/d) and was in complete remission 4 weeks after the initiation of steroid
therapy. This case shows that surgical excision and prednisolone therapy are useful for nephrotic syndrome associated with
Kimura's disease. 相似文献
44.
Yoichi Sato Hitoshi Yokoyama Masaaki Watanabe Osami Hamada 《Annals of thoracic and cardiovascular surgery》2003,9(6):401-405
A 74-year-old man with combined valvular disease with a recent cerebral infarction was admitted. While undergoing thorough examination for valvular disease, absent right superior vena cava (RSVC) and persistent left superior vena cava (PLSVC) were recognized. Chest X-ray film suggested a right arch protrusion, and CT and venogram confirmed the diagnosis. During surgery, replacement of the mitral and aortic valves and annuloplasty of the tricuspid valve were performed. A blood draining cannula was inserted in retrograde fashion from the coronary sinus into the PLSVC, without any difficulties in the tricuspid valve repair. Due to bradycardic atrial fibrillation, we believed that it would be difficult to insert an endocardial electrode postoperatively, hence myocardial electrode was placed in the right ventricular wall. Absent RSVC combined with PLSVC is very rare, and a patient who underwent combined valve surgery with this rare anatomical abnormality is herein presented. 相似文献
45.
Makoto Ishitobi Yasuo Miyoshi Akiko Ando Seiichi Hasegawa Chiyomi Egawa Yasuhiro Tamaki Morito Monden Shinzaburo Noguchi 《Clinical cancer research》2003,9(4):1376-1380
PURPOSE: The association of BRCA2 polymorphisms at codon 372 [Asn (N)/His (H)]and codon 784 [Met (M)/Val (V)] with breast cancer risk was evaluated in Japanese women. In addition, the prognostic significance of these polymorphisms was studied in breast cancer patients. EXPERIMENTAL DESIGN: A case-control study was conducted to examine the association of the BRCA2 N/H372 polymorphism and M/V 784 polymorphism with breast cancer risk (cases = 149, controls = 154). The prognostic significance of these polymorphisms was evaluated in 139 patients with primary breast cancer. RESULTS: No significant association was observed between the N/H372 polymorphism and breast cancer risk. In contrast, a significant increase in breast cancer risk (odds ratio, 2.03; 95% confidence interval, 1.07-3.87) was observed in carriers of the variant allele (V784) of the M/V784 polymorphism as compared with noncarriers after adjustment for the classical risk factors, age, family history, parity, body mass index, and so forth. Among breast cancer patients, various clinicopathological parameters including menopausal status, tumor size, lymph node status, histological grade, and estrogen-receptor status were not significantly different between the carriers and noncarriers of the variant allele with regard to both N/H372 and M/V784 polymorphisms. The N/H 372 polymorphism was not significantly associated with patient prognosis. On the other hand, breast cancer patients carrying the variant allele of M/V784 polymorphism showed a significantly (P = 0.014) lower 3-year disease-free survival rate (63%) than noncarriers (92%). Multivariate analysis has revealed that the M/V784 polymorphism is a significant prognostic factor, being independent of the other conventional prognostic factors such as lymph node status and estrogen receptor status. CONCLUSION: These results suggest that the M/V784 polymorphism, but not the N/H372 polymorphism, would be useful in the selection of women at high risk for developing breast cancer and would also serve as a clinically useful prognostic factor in breast cancer patients. 相似文献
46.
Binding characteristics of 3H-CGP12177 to beta-adrenoceptors in rat myocardial membranes 总被引:2,自引:0,他引:2
The present study was designed to examine the selectivity of 3H-CGP-12177 (4-(3-t-butylamino-2-hydroxypropoxy)-[5,7-3H]benzimidazole-2-one hydrochloride) for beta 1- and beta 2-adrenergic receptors by the Scatchard and the displacement analysis. The plots of specific binding obtained from the Scatchard analysis using 3H-CGP12177 for the rat myocardium membrane were uniphasic when the non-specific binding was determined by the use of 10 microM I-propranolol, and the Kd and Bmax values were 408.53 +/- 67.20 pM and 12.27 +/- 0.83 fmoles/mg protein, respectively. On the other hand, two binding sites were observed in the displacement curve when I-metoprolol was used as a competitor. The existence of these two binding sites implied the selectivity of 3H-CGP12177 to beta-adrenoceptors because 3H-CGP12177 was 1.8-fold more selective towards beta 1-adrenoceptors than beta 2-adrenoceptors. In addition, these two binding sites could be regarded as beta 1- and beta 2-adrenergic receptors from the evaluation of the binding characteristics beta-adrenoceptors by the displacement analysis using beta-selective antagonists. Thus, 3H-CGP12177, a hydrophilic radioligand, was useful for the binding assay of beta-adrenoceptors in rat myocardial membranes. 相似文献
47.
H Ohta F I Shane K Endo K Torizuka K Horiuchi A Yokoyama M Ishii 《Clinical nuclear medicine》1986,11(12):842-844
The effectiveness of Tc-99m bleomycin (BLM) and Tc(V)-99m DMSA are compared with that of Ga-67 citrate, which is currently the most widely used agent. In four patients with lipomatous tumors, the clinical significance of tumor imaging with each of these three agents is discussed and compared. Results indicate that both Tc-99m BLM and Tc(V)-99m DMSA are superior in detecting the extension or localization of liposarcomas. 相似文献
48.
49.
50.
Yoshio Takesue Takashi Yokoyama Takashi Kodama Yoshiaki Murakami Yuji Imamura Yuichiro Matsuura 《Surgery today》1997,27(5):392-397
This study was designed to determine the influence of ileal pouch capacity and anal sphincteric function on the clinical outcome
after ileal pouch-anal anastomosis. A total of 24 patients who had undergone ileal pouch-anal anastomosis (J pouch) for ulcerative
colitis were studied. The 24-hour stool frequency was found to be inversely correlated with the sensitivity threshold volume
(STV), maximal tolerance volume (MTV), and distensibility, but was independent of the maximal resting pressure and maximal
squeeze pressure. Patients experiencing nocturnal fecal incontinence had maximal resting pressures that were significantly
lower than those of nocturnally continent patients. Among the patients with fecal incontinence, those with frequent soiling
had lower resting pressures, STV, and distensibility than the patients with intermittent spotting. In addition, the STV in
patients needing nocturnal evacuation were lower than those of patients who did not evacuate after falling asleep. The conclusions
are as follows. Both stool frequency and the need for nocturnal pouch evacuation correlated directly with pouch volume. Anal
incontinence was more common in patients with low internal sphincteric function. In addition, frequent and gross nocturnal
incontinent patients demonstrate a worse function in both the anal sphincter and reservoir than those with intermittent spotting. 相似文献