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1.
Anthocyanins, which are responsible for a variety of bright colors (including red, blue, and purple) in fruits, vegetables, and flowers, are consumed as dietary polyphenols. Anthocyanin-containing fruits are thought to decrease coronary heart disease and are used in anti-diabetic preparations. Diabetes is associated with a variety of cardiovascular complications that may be mediated by endothelial dysfunction, and so this study was designed mainly to characterize the influence of a synthesized anthocyanidin derivative (HK-008) over acetylcholine (ACh)-induced relaxation in mesenteric arterial beds isolated from rats. In a glucose-tolerance test in intact rats, HK-008 (30 mg/kg) reduced the glucose level as effectively as the same dose of glibenclamide. The aortic relaxation induced by pinacidil (an ATP-sensitive potassium channel opener) was greatly inhibited by glibenclamide (10 microM), and also significantly inhibited by HK-008 (10 microM). Interestingly, the ACh-induced relaxation in the perfused, preconstricted mesenteric arterial bed was significantly enhanced by HK-008 (10 microM), and this enhancement was significantly attenuated by indomethacin (10 microM). The ACh-induced mesenteric relaxation was impaired by an increase in oxidative stress, viz. superoxide-generating treatment [xanthine oxidase (XO; 0.1 U/ml) plus hypoxanthine (HX; 10 microM)]. However, this impairment was strongly suppressed by HK-008 (10 microM). These results suggest that HK-008 increases endothelium-induced relaxation by suppressing oxidative stress or modulating prostanoids signaling. This compound may therefore be useful against certain cardiovascular disorders.  相似文献   
2.
Methyl-3,3,3-trifluoropropylsiloxane (F)-dimethylsiloxane (D) random and block copolymers were prepared. The random copolymers were prepared by equilibrium copolymerization starting from a mixture of cyclic F and D siloxanes with potassium silanolate as the catalyst. The F-D block copolymer was prepared by sequential anionic living polymerization of strained cyclic trisiloxanes using butyllithium as initiator, first polymerizing D3 then adding F3 after consumption of D3. The copolymer microstructure was established by means of 29Si NMR, differential scanning calorimetry (DSC), and gel-permeation chromatography (GPC). Characteristic glass transition temperature (Tg) shifts were observed depending on the F:D ratio of the random copolymers. It was demonstrated that the tensile strength of the poly(methyl-3,3,3-trifluoropropylsiloxane)-poly(dimethylsiloxane) (PTFPMS-PDMS) blend system was improved when either of the copolymers was added.  相似文献   
3.

Purpose

We investigated the changes in sexuality and quality of life that evolve after lower urinary tract reconstruction in neurologically impaired women previously treated with an indwelling urethral catheter.

Materials and Methods

A total of 18 neurologically impaired women treated with an indwelling urethral catheter underwent bladder reconstruction. Pubovaginal sling urethral compression was required to restore perineal dryness in 13 patients and was the only operation required in conjunction with intermittent catheterization in 3. Eight patients underwent ileocystostomy, that is creation of a "bladder chimney," and 4 underwent augmentation cystoplasty with creation of a continent catheterizable stoma. In 3 patients ileocystoplasty alone with intermittent urethral catheterization was performed. All patients were followed 6 to 40 months (mean 18) after reconstructive surgery using a 9-part questionnaire to score numerically the effect of surgical reconstruction on sexuality and quality of life issues.

Results

On a scale of 0 (worst) to 5 (best) mean scores for self-esteem improved from 1 preoperatively to 4 postoperatively, self-image from 1 to 4, sexual desire from 2 to 4 and ability to cope with disability from 1 to 4, respectively. In 4 of the 15 women who were sexually active preoperatively the frequency of sexual intercourse doubled from a mean of 3 to 6 times per month, respectively, and all 4 women reported improved sexual satisfaction. All 13 patients with pelvic pain and 5 with symptoms of autonomic dysreflexia noticed significant improvement if not complete resolution of the symptoms.

Conclusions

Neurogenic lower urinary tract dysfunction treated with an indwelling urethral catheter is detrimental to sexuality and quality of life in neurologically impaired women. Urinary tract reconstruction restores not only quality of life but also sexuality by improving self-image, self-esteem and the ability to cope. Indwelling catheterization as a method of long-term urinary treatment should be avoided in women.  相似文献   
4.
Sarcoidosis is a multi‐systemic disease of unknown etiology that results in the development of non‐caseating epithelioid granulomas. The liver is the third most frequently involved organ after the lymph nodes and the lungs. Most cases of liver sarcoidosis do not present with symptoms and involve minimal liver dysfunction, but some cases display progression to portal hypertension and liver cirrhosis, and finally to liver failure. The mechanism and the risk of progression in liver sarcoidosis are still unknown because of the diagnostic difficulty associated with this condition, and because follow‐up examinations can only be done in an invasive manner. Here, we present an informative case of liver sarcoidosis with rapid progression of esophagogastric varices. Four months prior to the definitive diagnosis, no signs of varices were observed on endoscopy, and developmentof esophagogastric varices, rapid progression, and eventual rupture occurred in a short period of time. A liver biopsy, carried out after endoscopic sclerotherapy, revealed that granulomas primarily affected the portal area without fibrotic and cirrhotic changes, which is considered a primary cause of portal hypertension and esophagogastric varices. Following the liver biopsy, the patient was given systemic steroids and is currently receiving outpatient care. Thus, we should consider the possibility that liver sarcoidosis, even in the absence of cirrhotic changes, can cause serious events such as esophagogastric variceal rupture following rapid progression as a result of portal hypertension.  相似文献   
5.
An 80-year-old woman was admitted with cardiogenic shock; she arrived in a deep coma with systolic blood pressure of 44 mmHg. An electrocardiogram showed ST elevation in I, aVL, V5 and V6, suggesting myocardial infarction in the lateral area of the left ventricle. A chest roentgenogram showed right pulmonary edema without cardiomegaly. Transthoracic and transesophageal echocardiograms revealed severe mitral regurgitation and a flailing anterior mitral valve leaflet, suggesting a ruptured papillary muscle. The patient was initially treated with high-dose dopamine, dobutamine and norepinephrine. Intraaortic balloon pumping was initiated after the patient's condition stabilized. She underwent emergency mitral valve replacement with a prosthetic valve. Complete rupture of the anterior papillary muscle was confirmed. Histological examination revealed necrosis of the anterior papillary muscle with inflammatory changes. She recovered uneventfully. Postoperative coronary angiography demonstrated subtotal occlusion of the first diagonal branch, and left ventriculography demonstrated akinesis of the lateral segment. This was a rare case in which subtotal occlusion of the first diagonal branch caused rupture of an anterior papillary muscle leading to severe mitral regurgitation.  相似文献   
6.
Although appendiceal anatomical anomalies are very rare, understanding of the anatomical details of these anomalies is important for surgery. In this case report, we present images from multi-detector row computed tomography (MDCT) and histological findings of a rare anatomical appendiceal anomaly originating from the cecum and opening into the terminal ileum like a bridge. These anatomical details were clearly depicted on MDCT with multi-planar reconstruction. MDCT demonstrated a communication between the appendix and terminal ileum. Histological analysis revealed that a normal mucosal layer was maintained from the appendix to the connected ileum, without any evidence of inflammatory or neoplastic changes, and only thickening of the muscular layer of the appendix was identified. Based on these histological findings, the appendix was considered to represent an anatomical anomaly rather than secondary fistula caused by inflammation or neoplasm, which has not yet been reported.  相似文献   
7.
8.
Effects of dual-action genistein derivatives on relaxation in rat aorta.   总被引:1,自引:0,他引:1  
Protein tyrosine kinases and nitric oxide (NO) play important roles in several cardiovascular diseases. In this study, we examined the actions of two compounds, each has structure of genistein (a tyrosine kinase inhibitor) and an NO donor, on endothelium-independent relaxation responses in the isolated rat aorta. By rational drug design, genistein was modified to acquire an NO donor, and we synthesized two such compounds (G-II, G-VI). These compounds and genistein induced dose-dependent relaxation responses in endothelium-denuded aortic strips, the rank order of potencies being G-VI > G-II > genistein. Incubation of endothelium-denuded strips with 1H-[1,2,4] oxadiazolo[4,3-a]-quinoxalin-1-one (ODQ, 10 microM), a guanylyl cyclase inhibitor, inhibited both the G-II- and G-VI-induced relaxations, but not the genistein-induced relaxation. The residual relaxations induced by these two compounds were similar to the genistein-induced relaxation. Incubation of endothelium-denuded strips with lysophosphatidylcholine (LPC, 20 microM)-which is a major atherogenic lysophospholipid component of oxidized low-density lipoprotein and is known to activate tyrosine kinase-caused a significant rightward shift in the dose-response curve for genistein. LPC also shifted the G-II- and G-VI-induced relaxation curves to the right; however, these relaxations in the presence of LPC were greater than that induced by genistein. The sodium nitroprusside-induced relaxation in endothelium-denuded strips was similar between in the absence and presence of LPC. These results suggest that each of our newly developed G-II and G-VI compounds has a dual action, as an NO donor and a tyrosine kinase inhibitor. These compounds may be useful against certain cardiovascular diseases.  相似文献   
9.
The purpose of this study was to examine whether the NHE with an increased lower leg slope angle would enhance hamstring EMG activity in the final phase of the descend. The hamstring EMG activity was measured, the biceps femoris long head (BFlh) and the semitendinosus (ST). Fifteen male volunteers participated in this study. Subjects performed a prone leg curl with maximal voluntary isometric contraction to normalize the hamstring EMG activity. Subsequently, subjects performed the NHE, with the help of a certified strength and conditioning specialist, while the lower leg slope angle were randomly set at 0° (NH), 20° (N20), and 40° (N40). To compare hamstring EMG activity during the NHE variations, the knee flexion angle was set in the range from 0° to 50°, divided into five phases (0–10°, 10–20°, 20–30°, 30–40° and 40–50°), where 0° indicated that the knee was fully extended. To calculate the knee extension angular velocity, the knee flexion angle divided by time, and break point angle (BPA) was the angle at which 10°/s was exceeded. In the statistical analysis, a two-way repeated measures ANOVA was used for the hamstring EMG activity and a one-way repeated measures ANOVA was used for the BPA. The EMG activity of the BFlh and the ST in N20 and N40 was significantly higher than in NH at knee flexion angle of 0–20° (p < 0.05). For the BPA, NH (57.75° ± 13.28°), N20 (36.27° ± 9.89°) and N40 (16.26° ± 9.58°) were significantly higher in that order (p < 0.05). The results of this study revealed that the NHE with an increased lower leg slope angle shifted the BPA to the lower knee flexion angle and enhanced the hamstring EMG activity in the final phase of the descent.Key points
  • The NHE with an increased lower leg slope angle enhances the hamstring EMG activity in the final phase of the descent.
  • The NHE with an increased lower leg slope angle shifts the BPA to the lower knee flexion angle.
  • The NHE with an increased lower leg slope angle may be an important rehabilitation exercise to prevent recurrence of HSIs.
Key words: Sports injuries, injury recurrence, hamstring muscles, electromyography, rehabilitation exercise, resistance training  相似文献   
10.
Skin cancer incidence rates are continuing to rise; however, if detected at an early stage, they can be cured with minimally invasive treatment. Therefore, the identification of novel and robust biomarkers for the early detection of skin cancer is required to improve the quality of life of the patient after treatment. In the present study, we aimed to identify novel biomarkers of skin cancers. We carried out serum metabolomics using gas chromatography/triple quadrupole mass spectrometry for two types of skin cancer: squamous cell carcinoma and melanoma. The changes in the expression of metabolites compared with healthy volunteers were analyzed by principal component analysis. Among all 118 metabolites, 27 in patients with squamous cell carcinoma and 33 in patients with melanoma showed significant changes in comparison with healthy volunteers. Principal component analysis showed that both skin cancer groups could be distinguished from the healthy volunteers group. We further investigated the specific metabolites most useful for these distinctions. In the squamous cell carcinoma group, these metabolites were glycerol, 4‐hydroxybenzoic acid, sebacic acid, fucose and suberic acid. In the melanoma group, these metabolites were glutamic acid, sebacic acid, suberic acid, 4‐hydroxybenzoic acid and phenylalanine. The present study identified several metabolites that were distinct for certain skin cancer types, which could potentially be used as diagnostic biomarkers leading to novel clinical management strategies.  相似文献   
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