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81.
Objectives:   To evaluate discrepancies in the detection of Bacille Calmette-Guerin (BCG)-resistant bladder cancer by cystoscopy, bladder biopsy and urinary cytology.
Methods:   Between January 1992 and August 2006, 127 bladder cancer patients underwent a cycle of eight weekly BCG instillations. Four weeks after the last BCG instillation, urinary cytological analysis and cystoscopy with targeted biopsy in addition to eight–nine selected-site biopsies were performed.
Results:   Biopsy-proven cancer was found in 11/27 (40.7%), 5/42 (11.9%), and 11/58 (19.0%) of positive, suspicious, and negative cytology cases, respectively. Abnormal and normal cystoscopic findings correlated with a biopsy-proven cancer in 13/53 (24.5%) and 14/74 (18.9%) cases, respectively. The combination of a macroscopic cystoscopic suspicion and a positive cytology missed malignant cases in 15.9% of the cases. In 100 cases without biopsy-proven cancer, the rates of denuded urothelium at biopsy in the cases with positive and non-positive cytology were 7/16 (43.8%) and 16/84 (19.0%), respectively
Conclusions:   According to our study, routine biopsy is recommended in the evaluation of BCG treatment, even if the timing, limitations and disadvantages of the procedure should be taken into account.  相似文献   
82.
Many studies have shown that esterified phosphorus (P) in diets has a favorable effect on mineral absorption in humans and animals. Phosphorylated oligosaccharides derived from potato starch increase calcium (Ca) absorption from the rat intestine both in situ and in vitro. We hypothesized that the feeding of potato starch has a potential to increase Ca or magnesium (Mg) absorption. Male Sprague-Dawley rats at 7 weeks were fed 4 types of diet containing either 60% sucrose, cornstarch, or 1 of 2 types of potato starch with different P contents for 1, 3, or 5 weeks. A balance test for Ca, Mg, and P was undertaken, and these mineral contents in the femur were determined for the 4 diet groups at each feeding period in vivo. Ingestion of potato starch increased Ca, Mg, and P excretion into feces and decreased the absorption rate of Ca and Mg. Femoral Ca contents were also decreased in the rats fed the potato starch diets compared with those in rats fed the sucrose or cornstarch diet. In vitro experiment in Ca absorption was undertaken using everted jejunal and ileal sacs of the small intestine in male Sprague-Dawley rats (7 weeks old). The potato starch application did not induce significant increase in Ca absorption compared with nonstarch (control) or cornstarch application. In conclusion, the ingestion of potato starch does not increase Ca and Mg absorption and rather accelerates their excretion, inducing the decrease in mineral absorption and retention in growing rats.  相似文献   
83.
BACKGROUND: Recent studies have shown that nitric oxide interacts with superoxide to form peroxynitrite, a potent oxidant that modifies cellular proteins producing 3-L-nitrotyrosine (N-Tyr). This study was designed to evaluate N-Tyr quantitatively with high-performance liquid chromatography (HPLC) during cardiac allograft rejection. METHODS: Rat transplanted hearts (allogeneic or syngeneic grafts) were examined with HPLC analysis, immunohistochemistry for N-Tyr, and histological studies on 0, 1, 3, and 7 days after transplantation. RESULTS: No histological rejection was found in syngeneic grafts, or day 0 or 1 allografts. HPLC demonstrated that N-Tyr in allografts increased on day 1 and continued to increase through day 7, while N-Tyr was not detected in any syngeneic grafts. Immunostaining of the allografts did not show N-Tyr on day 1. CONCLUSION: These results demonstrate that N-Tyr shows a time-dependent accumulation in cardiac allografts during acute rejection. N-Tyr detection using HPLC may be an useful maker for early diagnosis of acute rejection before pathological rejection occurs.  相似文献   
84.
A three-year-old boy with Ebstein's anomaly, who had received Starnes operation in the neonate state, successfully underwent staged total cavopulmonary connection. Despite of hypoplasticity of the pulmonary artery, the postoperative cardiac catheterization showed no elevation of pulmonary artery pressure and good cardiac performance. Although he suffered from supraventricular tachycardia in the early postoperative period, subsequent course was uneventful.  相似文献   
85.
Serous, mucinous, endometrioid, and clear cell adenocarcinomas arise from reproductive organs of mullerian origin. Although the mutation of PTEN, a tumor suppressor, is known to be involved in tumorigenesis of endometrioid adenocarcinomas of the endometrium and ovary, the role of PTEN alteration in endometrioid adenocarcinoma of the cervix remains to be investigated. To elucidate the molecular pathogenesis of cervical adenocarcinoma and adenosquamous carcinoma, and in particular to examine the potential role of PTEN mutation in endometrioid-type cancer of the cervix, we analyzed 32 cervical adeno- or adenosquamous carcinomas (8 endometrioid adenocarcinomas, 14 mucinous adenocarcinomas and 10 adenosquamous carcinomas) for PTEN mutations and HPV infections. PTEN mutation was detected in 2 of 8 (25.0%) endometrioid cases, 2 of 14 (14.3%) mucinous cases, and none of 10 (0%) adenosquamous cases. HPV DNA was detected in 11 out of 18 (61.1%) PTEN wild-type adenocarcinomas and 8 out of 10 (80.0%) adenosquamous carcinomas. Among 11 HPV-negative adenocarcinomas, 40.0% (2/5) endometrioid cases and 33.3% (2/6) mucinous cases were shown to be PTEN mutated, while no cases (0/21) were PTEN-mutant in the remainder (i.e. adenosquamous carcinomas and HPV-positive adenocarcinomas). The current observations suggest that PTEN mutation is frequently detected in HPV-negative adenocarcinomas of the cervix and the most prevalent occurrence of PTEN mutation in endometrioid subtype is keeping with endometrial and ovarian carcinomas.  相似文献   
86.
PURPOSE: To investigate the nature of capsular opacification after cataract-intraocular lens (IOL) surgery in rabbit eyes, we immunohistochemically located extracellular matrix components in lens capsules after the surgery using light microscopy. The study was conducted also to compare the extracellular matrix components in rabbit capsules with those previously reported in the human eye. METHODS: Twenty-seven eyes of 17 Japanese albino rabbits were lensectomized by phacoemulsification, and IOLs were implanted. Using immunohistochemical methods, the lens capsules were examined immediately after surgery, and 1, 2, 4, and 8 weeks after surgery. RESULTS: In all cases at each time point, the edge of the anterior capsulotomy had contracted and was found to adhere to the inner surface of the posterior capsule, with both IOL haptics remaining in the capsular bag. Collagen types I and III were detected around the adhesion between the anterior capsulotomy edge and posterior capsule during all stages of healing and also observed on the central posterior capsules 1 or more weeks after surgery. Immunoreactivity for cellular fibronectin was seen around the adhesion between the anterior capsulotomy edge and posterior capsule during all stages of healing. It was also detected on the posterior capsules 2 and 4 weeks after surgery, but disappeared 8 weeks after surgery. CONCLUSION: Extracellular matrix components such as collagen types I and III and cellular fibronectin were expressed inside the residual lens capsular bag. Cellular fibronectin may play a role in the early wound healing process in the postoperative posterior capsule because the immunoreactivity in the central posterior capsule disappears in the later phase of healing.  相似文献   
87.
BACKGROUND: Pulmonary venous obstruction (PVO) induces pulmonary arterial hypertension, as well as pulmonary venous hypertension, and jeopardizes the repair of cardiac lesions. METHODS: Four cases of congenital mitral stenosis and 4 cases of cor triatriatum (Lucas type A), ages ranging from 2 months to 16 years, were histologically examined on pulmonary vasculature. Histometrical analysis was performed on medial thickness and intimal changes of both pulmonary arteries and veins. For comparison, the examination of pulmonary vasculature in ventricular septal defect (VSD) cases was also performed. RESULTS: Medial thickening and intimal fibrosis, in both pulmonary arteries and veins with widespread lymphangiectasia, were characteristic vascular changes of PVO cases. Medial thickness of pulmonary arteries was correlated with preoperative pulmonary arterial pressure (PAP) (r = 0.77, p = 0.03 for systolic PAP), and greater than that of VSD cases. Medial thickness of pulmonary veins was also greater in PVO cases. Intimal fibrosis of pulmonary arteries and veins was seen extensively at the advanced ages, whereas no plexiform lesions or more advanced stages of pulmonary vascular disease were present. CONCLUSIONS: Congenital PVO induced progressive medial thickening and intimal fibrosis in pulmonary arteries and veins accompanied by lymphangiectasia. However, no plexiform lesions or more advanced stages of pulmonary vascular disease were present, which may explain the reversibility of pulmonary hypertension due to congenital PVO.  相似文献   
88.
Polymerization of 1-oxa-3-thiacyclopentane with catalytic amounts of triethyloxonium tetrafluoroborate was studied. The initiation reaction was a fast and quantitative formation of ethylsulfonium salt of monomer. The propagation reaction was a slow and quite complex reaction with sulfonium transfer reactions. The reaction mechanism is discussed.  相似文献   
89.
SM-15178, a new hydroxyacetophenone derivative, was evaluated to determine its antiinflammatory activity and antagonistic activity against leukotriene B4 (LTB4). SM-15178 inhibited [3H]LTB4 binding to its receptors on human neutrophils (IC50=0.30M). It inhibited LTB4-induced chemotaxis of human neutrophils (IC50 =0.72M) with little inhibitory effect against C5a or FMLP-induced chemotaxis at concentrations up to 30M. The compound alone did not cause human neutrophil chemotaxis at concentrations up to 10M. LTB4-induced chemotaxis of mouse and rat neutrophils and guinea pig eosinophils was also inhibited by the compound, with IC50 values of 0.55, 0.52, and 0.58 M, respectively. In an in vivo study, SM-15178, given orally, significantly prevented LTB4-induced transient leukopenia. It also suppressed LTB4-induced bronchoconstriction in the guinea pig almost completely when given orally at a dose of 40 mg/kg. Furthermore, orally given SM-15178 suppressed arachidonic acid-induced neutrophil infiltration in mouse ears and Arthus reaction-induced paw edema in the mouse in a dose-dependent manner. These results suggest that SM-15178 is a selective and orally active LTB4 antagonist and that it might be effective for the treatment of some types of inflammatory diseases.  相似文献   
90.
Deletion mapping of 18q in conventional renal cell carcinoma   总被引:2,自引:0,他引:2  
Loss of heterozygosity (LOH) is frequently associated with the inactivation of tumor suppressor genes. 18q LOH has been frequently reported in colorectal cancer and lung cancer; however, allelic loss on 18q has not been investigated in renal cell carcinoma (RCC). We evaluated LOH on 18q using nine microsatellite markers in 126 with conventional RCC (cRCC). LOH was observed in more than one 18q microsatellite locus in 24 cRCC (19%). We found the highest frequency of LOH (13.5%) at 18q21.3, where the DCC gene is located. We also assessed the relationship between LOH frequency and patient clinical parameters. Patients with a family history of cancer had a significantly higher frequency of 18q LOH than those without such a history (P=0.0017). No associations were found with other parameters, including gender, tumor grade, tumor stage, smoking status, and body mass index. The results suggest that inactivation of tumor suppressor genes at 18q21.3, including DCC and SMAD4 as candidates, may be involved in the tumorigenesis of some conventional RCCs.  相似文献   
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