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91.
To examine hemodynamic, plasma Catecholamines, and cyclic AMP changes during tilt in patients with neurocardiogenic (vasodepressor) syncope, six patients underwent 80± head-up tilt test for 10 minutes with isoproterenol infusion (1–3 μg/min). Venous blood was sampled in the supine position, at 3 minutes of tilt, and at the onset of vasodepressor reaction during tilt. AH patients had previous tilt studies in which vasodepressor syncope had been induced reproducibly (mean 3.3 episodes in each patient). Syncope was induced at 6.1 ± 0.4 minutes of tilt with an infusion of isoproterenol (mean 1.7 ± 0.3 fig/min). Although arterial pressure and heart rate did not change significantly between in the supine position and at 3 minutes of tilt, plasma norepinephrine increased significantly at 3 minutes of tilt (0.44 ± 0.10 ng/mL; P < 0.05) and at the onset of vasodepressor reaction (0.49 ± 0.12 ng/mL; P < 0.01) compared to the supine position with isoproterenol (0.34 ±0.10 ng/mL). Also, cyclic AMP (cAMP) increased significantly at 3 minutes of tilt (25.3 ± 2.0 pmol/mL; P < 0.005) and at the onset of vasodepressor reaction (29.6 ±1.7 pmol/mL; P < 0.005) compared to the supine position with isoproterenol (20.4 ±1.9 pmol/mL). After administration of selective beta1-blocker, metoprolol (40 mg/day), plasma norepinephrine, and cAMP during tilt did not change significantly compared to baseline tilt. However, metoprolol prevented the syncope in 3 of 6 patients. After administration of beta1-, beta2- blocker, propranolol (30 mg/day), cAMP at 3 minutes of tilt decreased significantly compared to the baseline tilt (16.9 ±1.4 pmol/mL vs 25.3 ± 2.0 pmol/mL; P < 0.05) and propranolol prevented the syncope in all six patients. We concluded that the increase of cAMP may play an important role for the induction of vasodepressor reaction in patients with neurocardiogenic (vasodepressor) syncope. The concentration ofcAMP showed more sensitive response to vasodepressor reaction than that of norepinephrine.  相似文献   
92.
High-performance liquid chromatographic (HPLC) analysis of human serum albumin (HSA) on Asahipak GS-520 showed at least two peaks, the principal component corresponding to human mercaptalbumin (HMA) and the secondary one to nonmercaptalbumin (HNA). HPLC analysis of HSA on Asahipak ES-520 N showed three peaks, the principal component corresponding to HMA, the secondary one to HNA having mixed disulfide with cysteine or glutathione and the tertiary one to HNA oxidized higher than mixed disulfide. Two kinds of rapid HPLC for the resolution of HSA into HMA and HNA were developed by the present authors. Using these HPLC, the present authors found a significant decrease in the fraction of HMA in the elderly.  相似文献   
93.
研究了促癌剂12—0—十四酰佛波—13—乙酸酯(TPA)对脂质过氧化的影响。经TPA处理的结肠癌细胞共脂质过氧化明显降低;经TPA处理的小鼠皮肤其脂质过氧初期升高,其后降低。γ—亚麻酸抵消TPA对小鼠皮肤脂质过氧化的影响。实验结果支持吞噬细胞,如中性粒细胞和巨噬细胞,对佛波酯的反应方式是产生超氧化物阴离子和氧自由基,但不表明氧自由基在促癌作用中起重要作用。推测促癌剂TPA引起脂质过氧化减弱的促癌过程。  相似文献   
94.
Discussions have just started in Japan as to the indication, technique and complication of endoscopic papillectomy for tumors of the papilla of Vater. We indicate endoscopic papillectomy for tumors satisfying the following:
  • 1 exposed tumor‐type adenoma, or carcinoma in adenoma;
  • 2 without invasion of duodenal muscularis; and
  • 3 no infiltration into the pancreas or the bile duct.
Endoscopic papillectomy was performed on 12 patients with tumors of the papilla of Vater that satisfied the above criteria. En bloc snare excision was achieved in 11 out of 12 cases without endoscopic sphincterotomy (EST) or epinephrine injection. Pancreatic stenting was done in 8 cases for prevention of pancreatitis, and bile duct stenting in nine cases for prevention of cholangitis. Postoperative early complications were observed in 5 cases; pancreatitis in 2; pancreatitis and bleeding in 1; bleeding in 1; and bleeding and perforation in 1. Neither recurrence nor metastasis of tumor has been detected during the average postoperative period of 620 days. The treatment can be acknowledged as less invasive therapy. However, management of complications is important, for which further study needs to be accumulated.  相似文献   
95.
We describe a patient in whom a suppressor/cytotoxic T cell lymphoma was suspected on the basis of histology and immunohistochemistry. DNA analysis of specimens from three different lesions, using restriction enzymes Eco RI and Bam HI, showed the same rearrangement of the T cell receptor beta-chain genes. We consider this technique to be of value in the early diagnosis of malignant lymphoma when differential diagnosis from other lymphoproliferative disorders is difficult with conventional methods.  相似文献   
96.
Chemosensitivity Test for Human Small Cell Lung Cancer Cell Lines In Vitro   总被引:1,自引:0,他引:1  
The in vitro response to seven chemotherapeutic drugs of threeestablished human small cell lung cancer (SCLC) cell lines (NCIH69, H 128, N231) was tested by a double soft agar clonogenicassay. Colony formation by the three cell lines was universallyreduced more than 50% by continuous exposure to peak plasmaconcentrations of all the drugs. However by exposure to one-tenthof the peak plasma concentrations, the colony growth of H69was reduced to 25.6% and 37.7% by etoposide and teniposide,respectively, and that of N231 was reduced to 46.7%, 39.0%,27.5% by carboplatin, etoposide and tenipo side, respectively.On the other hand colony formation by the three cell lines wasnot suppressed more than 50% by one-hour exposure to any ofthe drugs tested at one-tenth of the peak plasma concentrations.By one-hour exposure to drugs at the peak plasma concentrations,colony formation by H69, H128 and N23 I was reduced more than50% by cisplatin, etoposide, teniposide and nimustin, by adriamycin,tenoposide and ACNU, and by adriamycin, etoposide, teniposideand nimustin, respectively. It was concluded that these threecell lines have similar sensitivity to seven drugs commonlyused against small cell lung cancer.  相似文献   
97.
An asymptomatic patient with pre-operatively diagnosed solitary angiomyolipoma is reported. The tumour was a well defined, fat density mass on computerized tomography (CT) and magnetic resonance imaging (MRI), and a hyperechoic nodule with a sharp margin on ultrasonography (US). The lesion was hypervascular on arteriography and CT during hepatic angiography. Chemical shift MRI confirmed the fat component within the lesion. Although a review of the literature shows this tumour to be rare and difficult to differentiate from a malignant lesion pre-operatively, the pre-operative diagnosis of angiomyolipoma is considered feasible when the characteristic findings as described here are present.  相似文献   
98.
Ultrastructural, immunohistochemical and gene analytical studies were carried out on a 39-year-old patient with lymphomatoid papulosis. Two different cell groups were demonstrated in the papulonodular eruptions: large atypical cells with multiple nuclei that were well stained with anti-Tac, but not with Leu 3a, and other cells that possessed prominent hyperchromatic nuclei and which stained well with Leu I and Leu 3a but not with anti-Tac. Gene analytical studies using EcoRI, BamHI and HindIII revealed no rearrangement, indicating a non-clonal T-cell proliferation unlike malignant T-cell lymphoma. These results suggest that the present case was benign.  相似文献   
99.
Thirty-two consecutive patients with paroxysmal supraventricular tachycardias, with previously defined mechanisms of the tachycardias, were interviewed by noninvestigators about whether they experienced symptoms of diuresis during or at the termination of the tachycardias, to test the hypothesis that patients with AV nodal reentrant tachycardia would have a feeling of diuresis, polyuria, or both during or at the termination of the tachycardia. Twelve of the 13 patients with AV nodal reentrant tachycardia (92%), two of the 15 patients with AV reentrant tachycardia (13%), and one of the 4 patients with atrial flutter associated with 2:1 AV conduction (25%) felt diuresis during or at the termination of the tachycardias (AV nodal reentrant tachycardia vs other forms of tachycardia; P < 0.001). In 14 of the 32 patients, the right atrial pressure and plasma atrial natriuretic peptide (ANP) concentration were measured during both the tachycardias and sinus rhythm. The mean right atrial pressure during AV nodal reentrant tachycardia was significantly elevated compared to that during other forms of tachycardia (P < 0.01). The plasma ANP concentration during AV nodal reentrant tachycardia was also elevated significantly compared to that during other forms of tachycardias (P < O.OO1). There were no significant differences in the cycle lengths of the tachycardias, age, left atrial dimensions, or the left ventricular ejection fraction between the AV nodal reentrant tachycardia and the other forms of tachycardia. We concluded that the feeling of diuresis during or at the termination of tachycardia was a more common symptom in patients with AV nodal reentrant tachycardia. The higher secretion of plasma ANP from the right atrium might be involved in the mechanism of this symptom.  相似文献   
100.
To examine the expression of p53 protein and gene alterations in oral epithelial lesions including epithelial dysplasias and primary squamous cell carcinomas, immunohistochemical and temperature gradient gel electrophoresis (TGGE) methods were applied to formalin-fixed and paraffin-embedded tissues. Morphologically normal mucosal epithelium stained negatively for p53 protein. Three out of 11 (27·3 per cent) epithelial dysplasias and 19 out of 57 (33·3 per cent) primary squamous cell carcinomas stained positively for p53 protein. Although more than half of the cases were positive for p53 protein in stage I, the positive cancer cases were found at other stages with variable frequency. Immunoreactive products were localized in the nucleus, especially in the basal and suprabasal layers. The analysis by TGGE revealed gene alterations in exons 5–8 in 3 out of 3 epithelial dysplasias and 17 out of 19 (89·5 per cent) primary squamous cell carcinomas which were immunohistochemically positive for p53 protein. These results suggest that p53 gene mutation may be involved in carcinogenesis in the oral squamous epithelium even in the early stage of the dysplasia–carcinoma sequence.  相似文献   
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