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11.
The effects of the local blood circulation and absolute torque on muscle endurance at different knee-joint angles were determined. The rate of muscle deoxygenation (using near-infrared spectroscopy), and the rate of muscle fatigue (using the slope of integrated electromyography, iEMG) were evaluated concurrently. Nine healthy subjects performed submaximal (50% maximal voluntary contraction, MVC) static knee extension at 50° (extended position, EXT) and 90° (flexed position, FLEX) joint angles until the target torque could no longer be maintained: that time was measured as the endurance time. They exercised with the circulation occluded (OCCL), and without (FREE) to study the possible effects of the local circulation. Although MVC torque was independent of joint angle [mean (SD) FLEX 250.6 (51.7) N·m and EXT 246.5 (46.6) N·m], significantly shorter (P<0.01) endurance time in FLEX [FREE 71.1 (10) s and OCCL 63.1 (8.8) s] than at EXT [FREE 115.3 (30) s and OCCL 106.7 (29.1) s] were obtained in both circulatory conditions. The iEMG-time slope was significantly greater in FLEX at the proximal and distal portion (P<0.05) in both circulatory conditions. Muscle deoxygenation rate in OCCL was significantly greater (P<0.05) at FLEX [20.8 (8.0)%] than EXT [10.9 (4.0)%]. The results would suggest that different knee-joint angle affects muscle endurance even if the local circulation is controlled. Circulatory disturbance would further reduce muscle endurance in EXT, but not in FLEX. Because of the greater muscle internal force in FLEX, local blood flow might be already limited even with a free circulation. The greater muscle deoxygenation and muscle fatigability would be related to the shorter muscle endurance in FLEX. Electronic Publication  相似文献   
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The hydrochlorides of p-nitrophenyl 6-aminocaproate ( 4a ), p-nitrophenyl 12-aminododecanoate ( 4b ), and p-nitrophenyl 12-(6-aminocaproylamino)dodecanoate ( 6 ) were prepared and polycondensed in 1,2,4-trichlorobenzene in the presence of tributylamine under different conditions. The polycondensation of 6 at 128°C gave the alternating copolyamide (PA 6, 12). The polymers were identified by DTA and by 13C NMR.  相似文献   
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In general, steroid is mainly used as anti-inflammatory action in case of allergic diseases. As one of the side effects of inhalation steroid, a report is given below regarding buccal capsule/esophageal candidiasis. The patient came to the hospital with the chief complaint regarding passage dysphagia in the time of deglutition; pharyngitis and esophageal candidiasis were found by endoscopy of upper gastrointestinal tract.The interview after the endoscopy revealed that the patient, a 69-year-old female was diagnosed as chronic perennial allergic rhinitis a few years ago, and had been inhaling rhinenchysis Beclometasone dipropionate (BDP) before sleep every day for the past two years because using this collunarium seemed to mitigate the nasal obstruction and mucus during sleep. The patient did not report this fact before the endocsopy because she did not associate it with her subjective symptom. In this case, it was assumed that nebulized rhinenchysis BDP was accidentally swallowed to the pharynx and esophagus during sleep. As a treatment, rhinenchysis BDP was canceled and instead Azunol mouth washing (gargling/nasal douche) was used. No antifungal agent was used. In two weeks, the patient reported some improvement, and this was confirmed by reexamination of the upper gastrointestinal tract using endoscope in one month and a half. Pharyngitis was improved, and in the digital endoscopic assessment of esophageal candidiasis complicating inhaled steroid therapy the esophageal candidiasis became Grade I (mild grade). As for the later progress, the patient did not report any subjective symptoms such as nasal obstruction and dysphagia. In addition, the inflammation caused by candidiasis and found in the early examination was improved. The patient in this case was under treatment for thrombosis in the vein of lower extremity, but no complications such as diabetes mellitus or immune deficiency syndrome were observed. DISCUSSION: Esophageal candidiasis by chronic administration of inhalation of steroid before sleep for asthmatic patients has been reported. However, there has not been a report of esophageal candidiasis by chronic administration of rhinenchysis steroid before sleep for patients with allergic rhinitis. Similarly, in the case of the use of steroid in the form of collunarium before sleep, steroid stayed in the esophagus via the transendothelial nasal cavity, and that seemed to cause, in the long run, to develop esophageal candidiasis. CONCLUSIONS: One of the implications of the above case is that collunarium can go down, even when it is nebulized in the nasal cavity, to the esophagus via the nasal cavity to buccal capsule. This suggests the necessity for preventative measures in the case of chronic administration of steroid as follows. A. Blowing of the nose just after the use of collunarium B. Daily rinsing (gargling and nasal douche).  相似文献   
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In isolated buccal segment of the rabbit facial vein, electrical responses produced by perivascular nerve stimulation and exogenously applied noradrenaline (NA) were recorded from the smooth muscle cells using microelectrode. Perivascular nerve stimulation hyperpolarized the smooth muscle cell membrane. The hyperpolarization was converted to depolarization after application of the -adrenoceptor antagonist, propranolol, and the depolarization was blocked by 2 antagonists, yohimbine. These responses elicited by nerve stimulation were blocked by tetrodotoxin or guanethidine, but not by atropine. Exogenously applied NA mimicked the responses elicited by nerve stimulation. The amplitude of the -adrenoceptor-mediated hyperpolarization was increased in low potassium solution, decreased in high potassium solution, but unaltered by low sodium or low chloride solution, i.e., the hyperpolarization may be generated by an increase in potassium conductance of the membrane. An involvement of the apamin-sensitive (Ca-dependent) potassium channel or sodium-potassium ATPase in the hyperpolarization was ruled out.  相似文献   
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The basis of rhythmic activity observed at the dorsal column nuclei (DCN) is still open to debate. This study has investigated the electrophysiological properties of isolated DCN neurones deprived of any synaptic influence, using the perforated-patch technique. About half of the DCN neurones (64/130) were spontaneously active. More than half of the spontaneous neurones (36/64) showed a low threshold membrane oscillation (LTO) with a mean frequency of 11.4 Hz (range: 4.3–22.1 Hz, n = 20; I = 0). Cells showing LTOs also invariably showed a rhythmic 1.2 Hz clustering activity (groups of 2–5 action potentials separated by silent LTO periods). Also, more than one-third of the silent neurones presented clustering activity, always accompanied by LTOs, when slightly depolarised. The frequency of LTOs was voltage dependent and could be abolished by TTX (0.5 μM) and riluzole (30 μM), suggesting the participation of a sodium current. LTOs were also abolished by TEA (15 mM), which transformed clustering into tonic activity. In voltage clamp, most DCN neurones (85 %) showed a TTX-/riluzole-sensitive persistent sodium current ( I Na,p), which activated at about -60 mV and had a half-maximum activation at −49.8 mV. An M-like, non-inactivating outward current was present in 95 % of DCN neurones, and TEA (15 mM) inhibited this current by 73.7 %. The non-inactivating outward current was also inhibited by barium (1 mM) and linopirdine (10 μM), which suggests its M-like nature; both drugs failed to block the LTOs, but induced a reduction in their frequency by 56 and 20 %, respectively. These results demonstrate for the first time that DCN neurones have a complex and intrinsically driven clustering discharge pattern, accompanied by subthreshold membrane oscillations. Subthreshold oscillations rely on the interplay of a persistent sodium current and a non-inactivating TEA-sensitive outward current.  相似文献   
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A 51-year-old Japanese man who underwent a standard distal gastrectomy for cancer of the stomach developed abdominal pain when oral intake was commenced on the 6th postoperative day after an uneventful postoperative course. Complete obstruction of the jejunum led to a sudden deterioration in his general condition and a laparotomy was performed, revealing counterclockwise rotation of the mesenterium. The necrotic portion of the small intestine was removed, while 10 cm of the upper jejunum and 100 cm of the terminal ileum were preserved. His second postoperative course was uneventful apart from the development of intestinal hurry, which is now under medical control 9 months after his second laparotomy.  相似文献   
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Bropirimine [2-amino-5-bromo-6-phenyl-4-(3H)-pyrimidinone] is a low-molecular-weight compound that acts as an inducer of interferon in several animal species. Experiments were designed to explore the possibility of using this drug for the treatment of renal-cell carcinoma (RCC). Euthymic BALB/c mice were inoculated with murine RCC (Renca) cells and given graded doses of Bropirimine p.o. for 5 consecutive days beginning on day 1 following tumor inoculation. These mice were killed and tumors were excised on day 21. Bropirimine significantly (P<0.01) inhibited the tumor growth at a daily dose of 1,000 or 2,000 mg/kg. No adverse effect or toxicity was noted at 1,000 mg/kg, and at 2,000 mg/kg there was only a marginal body-weight reduction without any other appreciable side effect. In addition to the inhibition of tumor growth, there was a small yet significant (P<0.05) increase in the duration of survival (in days) in the Bropirimine-treated animals. When the treatment was delayed to begin on day 6 following tumor inoculation, Bropirimine did not suppress tumor growth in euthymic mice, pointing to the importance of the timing of the treatment. In athymic nude BALB/c mice lacking T-cells or T-cell function, Bropirimine also inhibited tumor growth (P<0.01). The antitumor effect of this drug was abolished by pretreatment with anti-asialo GM1 serum, which eliminated natural killer (NK) activity in euthymic mice. In vivo treatment with Bropirimine augmented the cytotoxicity of lymphocytes isolated from the spleens or lungs of the tumor-bearing mice, which were active against Renca and YAC-1 cells in vitro. This activity was NK-cell-dependent as judged on the basis of the results of the in vitro complement-dependent cytotoxicity assay. Since Bropirimine induced interferon (IFN)-/ production, significantly (P<0.05) elevating its serum concentration, and since this drug mimics the effects of IFN-/, it seemed likely that the Bropirimine-induced NK cell augmentation we found was mediated by IFN-/. These results suggest that Bropirimine, a booster of NK activity, may have potential as an adjunct to other therapeutic modalities in the treatment of human RCC.  相似文献   
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