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31.
Beh?et's disease (BD) is a systemic inflammatory disorder of unknown etiology, and rarely complicated with myelodysplastic syndrome (MDS). In the present study, we investigated the morphological myelodysplasia and apoptotic rate of bone marrow cells in 15 patients with BD in comparison with MDS patients. Morphological myelodysplasia of bone marrow cells was detected in 53.3% of BD, but none showed chromosomal abnormalities. The apoptotic rate in BD patients (26.1 +/- 8.4%) was significantly higher in normal controls (11.3 +/- 2.4%; p < 0.005) and significantly lower in patients with MDS (50.8 +/- 14.0%; p < 0.0001). These findings suggest that myelodysplasia in patients with BD is more frequent than expected, and possibly due to excess induction of apoptosis of bone marrow cells in BD. However, the rate of apoptotic bone marrow cells is lower than MDS, which may explain the slight peripheral cytopenia in BD, distinct from that in MDS.  相似文献   
32.
Cardiac troponin T(cTnT) is one of the most myocardial-specific markers for the diagnosis of acute myocardial infarction(AMI). Recently, the rapid bedside cTnT assay(Trop T rapid assay sensitive version), which can provide qualitative determinations within 15 min, has been developed for the emergency clinical setting. To evaluate the usefulness of rapid bedside cTnT assay, we performed the Trop T test and measured serum levels of myoglobin(Mb), creatine kinase MB isoenzyme(CK-MB) and cTnT in 256 consecutive emergency patients with suspected AMI(65 found to have AMI and 191 without AMI). The diagnostic sensitivities for AMI of Trop T, Mb and CK-MB measurements were 66%, 92% and 52%, respectively, whereas the specificities were 80%, 18% and 74%, respectively. The diagnostic accuracy for AMI of Trop T(77%) was significantly higher than that of Mb(37%, p < 0.001) and CK-MB(69%, p < 0.05). The sensitivity for AMI of Mb(86%) was significantly(p < 0.001) higher than that of Trop T (31%) and CK-MB(31%) in patients admitted < or = 3 hr after the onset of AMI. In contrast, the sensitivities of Trop T(80% and 100%) in patients admitted at 3-6 hr and > 6 hr showed no significant differences from those of Mb(100% and 96%). Furthermore, Trop T in patients admitted > 6 hr had significantly(p < 0.01) higher sensitivity compared with CK-MB(69%). The mortality rate in the non-AMI group during hospitalization in patients with positive Trop T test(39%) was significantly(p < 0.001) higher than that in patients with negative test(9%). When the positive Trop T test was regarded as > or = 0.10 ng/ml of serum cTnT, Trop T test had the best concordance of 92% with a quantitative of cTnT assay.  相似文献   
33.
Ws/Ws rats have a small deletion at the tyrosine kinase domain of the c- kit gene and are deficient in both mucosal mast cells (MMC) and connective tissue-type mast cells (CTMC). The role of the c-kit receptor in the development of MMC and CTMC was investigated by infecting Ws/Ws and control +/+ rats with Nippostrongylus brasiliensis (NB), which induces T-cell-dependent mast cell proliferation. Although mast cells did not develop in the skin of Ws/Ws rats, a significant number of mast cells developed in the jejunum after NB infection. These mast cells had the MMC protease phenotype (rat mast cell protease [RMCP] I-/II+) and lacked heparin because they were not stained with berberine sulfate. Globule leukocytes were also detected in the mucosal epithelium of these rats. However, the number of MMC and the serum concentration of RMCP II in NB-infected Ws/Ws rats were only 13% and 7% of those of NB-infected +/+ rats, respectively. A small number of mast cells also developed in the lung, liver, and mesenteric lymph nodes of Ws/Ws rats after NB infection. Although mast cells in these tissues had the MMC phenotype throughout the observation period, the increased mast cells in the lung and liver of +/+ rats acquired a CTMC-like phenotype and were RMCP I+/II+, berberine sulfate+, and formalin resistant. These results indicate that the need for the stimulus through the c-kit receptor appears to be greater in the development of CTMC in the skin as well as for CTMC-like mast cells in the lung and liver than for the development of MMC.  相似文献   
34.
The W locus of mice encodes the c-kit receptor tyrosine kinase. Heterozygous WJic/+ and Wn/+ mice and homozygous Wf/Wf mice were similar in appearance; all of them have large depigmented areas lacking any well-defined pattern. The WJic, Wn, and Wf mutant alleles were characterized and their molecular nature was correlated with the mast cell differentiation in the skin and the biologic features of cultured mast cell (CMC). All WJic, Wn, and Wf were point mutations at the tyrosine kinase domain, and c-kit mRNA was normally transcribed from all of them. The mature 145-Kd form of the c-kit protein was produced from the WJic and Wf alleles, but not from the Wn allele. c-kit proteins produced by the WJic or Wf allele were expressed on the surface of CMCs, but those of the Wn allele were not. When double heterozygous mice were produced between W and WJic and between W and Wn, both W/WJic and W/Wn mice lacked skin mast cells. W/WJic CMCs and W/Wn CMCs did not survive in the coculture with fibroblasts. W/WJic CMCs normally attached to fibroblasts, but W/Wn CMCs did not. The defect of W/Wn CMCs in the attachment was attributed to the deficient extracellular expression of the c-kit protein. The number of skin mast cells was compared among WJic/+, Wn/+, Wf/+, and Wf/Wf mice. Mast cells decreased in WJic/+ and Wf/Wf mice, but not in Wn/+ and Wf/+ mice. Although the Wn was a point mutation at the kinase domain, the biologic effect of the Wn was comparable with that of the W mutant allele, which produces truncated c-kit protein without the transmembrane domain. The weak phenotype of Wn/+ mice may be explained by the deficient extracellular expression of c-kit proteins produced by the Wn allele. When WJic/WJic, Wn/Wn, and Wf/Wf CMCs were stimulated by the recombinant c-kit ligand, autophosphorylation activity was observed only in Wf/Wf CMCs. This result was consistent with the weak biologic effect of the Wf mutant allele.  相似文献   
35.
Turpentine is a renewable resource, has good combustion performance, and is considered to be a fuel or promising additive to diesel fuel. This is very important for the investigation of thermal stability and energy oxidation characteristics, because evaluation of energy or fuel quality assurance and use safety are necessary. The main components of turpentine are α-pinene and β-pinene, which have unsaturated double bonds and high chemical activity. By investigating their thermal stability and oxidation reaction characteristics, we know the chemical thermal properties and thermal explosion hazard of turpentine. In this present study, the thermal stability and oxidation characteristics of α-pinene, β-pinene and α-pinene/β-pinene mixture were investigated using a high sensitivity accelerating rate calorimeter (ARC) and C80 calorimeter. The important parameters of oxidation reaction and thermal stability were obtained from the temperature, pressure and exothermic behavior in chemical reaction. The results show that α-pinene and β-pinene are thermally stable without chemical reaction under a nitrogen atmosphere even when the temperature reaches 473 K. The initial exothermic temperature of the two pinenes and their mixture is 333–338 K, and the heat release (−ΔH) of their oxidation is 2745–2973 J g−1. The oxidation activation energy (Ea) of α-pinene, β-pinene and α-pinene/β-pinene mixture is 116.25 kJ mol−1, 121.85 kJ mol−1, and 115.95 kJ mol−1, respectively. There are three steps in the oxidation of pinenes: the first is the induction period of the oxidation reaction; the second is the main oxidation stage, and the pressure is reduced; the third is thermal decomposition to produce gas.

Turpentine is a renewable resource, has good combustion performance, and is considered to be a fuel or promising additive to diesel fuel.  相似文献   
36.
With the use of two-dimensional echocardiography (2DE), we analyzed apical and subcostal four-chamber views for evaluation of right ventricular (RV) function in 30 individuals as compared to RV ejection fraction (RVEF) obtained by radionuclide angiography. In addition to previously reported parameters of changes in areas and chords, a new simple measurement of tricuspid annular excursion was correlated with RVEF. A close correlation was noted between tricuspid annular plane systolic excursion (TAPSE) and RVEF (r = 0.92). The RV end-diastolic area (RVEDA) and percentage of systolic change in area in the apical four-chamber view also showed close correlation with RVEF (r = -0.76 and 0.81); however, the entire RV endocardium could only be traced in about half of our patients. The end-diastolic transverse chord length and the percentage of systolic change in chord length in the apical view showed a poor correlation with RVEF. The correlation between RVEF and both areas and chords measured in the subcostal view was poor. It is concluded that the measurement of TAPSE offers a simple echocardiographic parameter which reflects RVEF. This measurement is not dependent on either geometric assumptions or traceable endocardial edges. When the endocardial outlines could be traced, the apical four-chamber view was superior to the subcostal view in assessment of RV function.  相似文献   
37.
Microcomputers have been used in our hospital for the past five years to summarize data from patients and to remind us to carry out routine tests. Recently, we have shown computer data on the screen to patients; this helps us to explain and discuss the monitoring of their condition with them. Unlike some other systems, general data as well as data on self-monitored blood glucose levels are recorded in our computer system. The data consist of five categories: personal profile, treatment, etiological research, indices of control and data for checking complications. The analysis and evaluation of our system are done by the modes of display, statistical calculations, early detection of complications and graphics. The system is compatible with input from a keyboard, optical character readers and interface to a glucose meter with a memory.  相似文献   
38.
目的:已有报道认为,经腹会阴直肠切除术比保留括约肌的经腹直肠切除术术后局部复发率和死亡率高的多。该旨在比较经腹会阴直肠切除术和保留括约肌的经腹直肠切除术患的肿瘤学结果。方法:回顾性分析了1989年4月至2002年4月期间,新加坡中央医院结肠直肠外科进行根治性直肠切除术的直肠癌患病历。共791例患纳入该研究。手术操作方式分为经腹会阴直肠切除术、经腹直肠切除直接吻合术和经腹直肠切除肛管吻合术。对直肠下半段和下1/3肿瘤进行常规全直肠系膜切除。前瞻性追踪不良事件,包括局部和全身复发或患病率和死亡率。结果:93例进行经腹会阴直肠切除术(12.1%),547例进行经腹直肠切除直接吻合术(71%),130例进行经腹直肠切除肛管吻合术(16.9%)。术后死亡率为2.6%,患病率为13.6%。所有患术后吻合口漏的发生率为2.5%。累计5年的局部复发率分别为:经腹会阴直肠切除术5.4%、经腹直肠切除直接吻合术3.6%、经腹直肠切除肛管吻合术3.8%(P=0.73,对数秩检验)。不同术式局部复发的均因为有肛门鳞状异常增生被随访。活检证实为异常增生,且通常为多病灶发病。异常增生的分级各不相同,但其中28例患至少有1处病灶为重度异常增生。  相似文献   
39.
40.
AIM: To investigate the efficacy of tissue adhesives for closing the orifice of the inguinal hernia sac (IHS) as an alternative method for treating inguinal hernia. METHODS: Five-week-old male Lewis rats (n=4) were used, because Lewis rats have a large patent IHS. The rats were divided into 9 groups (n=6 in each) according to the type of tissue adhesive used: G1, fibrin glue (Beriplast); G1b, Beriplast plus blood; G2, microfibrillar collagen hemostat (Avitene); G2b, Avitene plus blood; G3, fibrinogen-based sealant (TachoComb); G3b, TachoComb plus blood; G4, synthetic absorbable sealant (Advaseal); G5, bilateral single port laparoscopic injection of octylcyanoacrylate (Dermabond); and G6, sham operation (control group). In G1-G4, surgery was performed through a midline lower abdominal incision. In G5, a 5-mm laparoscope was inserted in the epigastrium, a fine catheter was passed through the side port of the laparoscope into the right HIS, and 0.2 mL Dermabond was injected. The left IHS was treated in the same way. All rats were sacrificed 3 months after treatment, and IHS patency was examined macroscopically. All rats in G5 and G6 were mated 50 days after treatment to check fertility. RESULTS: All rats survived until sacrifice. At sacrifice, all IHS were patent in G6. All IHS were also patent in G1-G4, but all IHS were closed at the internal ring in G5. In G5 there were no adhesions between the orifice of the closed sac and the small bowel in 5/6, and only minor adhesions in 1/6. G5 fertility (5/6: 83%) was the same as for the control group (G6). CONCLUSION: Our results suggest that laparoscopic injection of Db into the IHS is simple, safe, reliable, virtually scarless, and may be a reasonable alternative to standard open surgical inguinal hernia repair.  相似文献   
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