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91.
X-linked syndrome of platelet dysfunction, thrombocytopenia, and imbalanced globin chain synthesis with hemolysis 总被引:6,自引:5,他引:1
An unusual family is described with a congenital bleeding disorder present in four males belonging to three generations. Of the three surviving affected males, all had splenomegaly and petechiae. The three had moderate thrombocytopenia (55-90 X 10(9)/liter) and markedly prolonged Ivy-template bleeding times (greater than 30 min). They were also noted to have reticulocytosis and, upon further investigation, imbalanced globin chain synthesis resembling that of beta-thalassemia minor. Studies on nine additional family members in four generations were normal except for slight elevations of reticulocyte counts in female members, one of whom had the abnormal globin chain synthesis ratio. In male members, the bleeding tendency and clinical signs always occurred in the presence of the globin chain synthesis defect and reticulocytosis. This previously undescribed condition was apparently transmitted as an X-linked disorder. 相似文献
92.
93.
Cuello C; Palladinetti P; Tedla N; Di Girolamo N; Lloyd AR; McCluskey PJ; Wakefield D 《Rheumatology (Oxford, England)》1998,37(7):779-783
OBJECTIVE: To investigate the expression and source of chemokines in minor
salivary gland biopsies (MSGs) in patients with Sjogren's syndrome (SS).
METHODS: Immunohistochemical analysis was used to determine the pattern of
chemokine expression in MSGs from patients with (n=6) and without (n=5) SS,
as well as to examine the phenotype of both resident and infiltrating cells
expressing chemokines. RESULTS: Significant differences in the number of
infiltrating mononuclear (MN) cells in patients with and without SS were
noted. Ductal epithelial cells of SS biopsies expressed significantly
increased levels of macrophage inflammatory protein (MIP)-1alpha,
MIP-1beta, interleukin-8 (IL-8) and RANTES (Regulated upon Activation,
Normal T cell Expressed and Secreted). Biopsies from patients with SS
showed that MIP-1beta was expressed by 51% of infiltrating cells, while 41%
expressed MIP-1alpha, whereas 22 and 7% expressed RANTES and IL-8,
respectively. CONCLUSION: Chemokines expressed by ductal epithelial cells
may attract circulating leucocytes, in particular CD4+ T cells, towards the
site of inflammation, thereby orchestrating the influx of MN cells
characteristically seen in MSGs in SS. Chemokines may be induced directly
by a putative triggering agent for SS, or secondary to the release of
pro-inflammatory cytokines produced by epithelial cells. These findings
further implicate epithelial cells as playing a major role in the
pathogenesis of SS and implicate chemokines in the leucocyte recruitment in
this setting.
相似文献
94.
95.
Spinning top urethra (STU) is a term used to describe a widened posterior urethra seen mainly in girls. It is commonly regarded as a normal variant. The authors studied 30 girls with STU using videourodynamics. Twenty-eight showed bladder instability; 21, a congenital wide bladder neck anomaly; and 20, both instability and a wide bladder neck. One patient had a sensitive bladder. All patients had a urodynamic abnormality. The authors believe that the STU is nearly always an indication of bladder instability or wide bladder neck anomaly. The most common mechanism for the dilatation of the posterior urethra is that unstable contractions are resisted by a voluntary increase in distal sphincter tension so as to prevent leakage of urine. The resulting pressure rise produces distention of the posterior urethra, which will be maximal in subjects with a weak bladder neck mechanism as in the congenital wide bladder neck anomaly. The authors believe that STU is seldom if ever a normal variant. 相似文献
96.
The platelet release reaction was studied by a new quenched-flow approach. Platelets labeled with 14C-serotonin were reacted for short times (up to 5 sec) with thrombin and then quenched with glutaraldehyde or paraformaldehyde. Serotonin secretion began within 1 sec and was nearly complete by 4 sec. Aggregation recorded by a resistive-particle counter was similarly fast. Therefore, the quenched-flow system reveals that serotonin secretion can occur more rapidly than estimated in earlier studies. 相似文献
97.
Fatih Alper Atila Turkyilmaz Serpil Kurtcan Yener Aydin Omer Onbas Hamit Acemoglu Atilla Eroglu 《European journal of radiology》2011,80(3):625-628
Purpose
We have investigated the utility of the STIR TSE sequence in the differentiation of benign from malignant mediastinal lymph nodes in patients with esophageal cancer.Patients and methods
This study included 35 consecutive patients who were diagnosed as esophageal cancer and were undergone surgery. STIR TSE sequences were obtained as the ECG trigger. The signal intensity of the benign and malign lymph nodes, normal esophagus, and pathologic esophagus can be calculated on STIR sequence.Results
Pathologically, the number of total lymph nodes in 35 operated cases was 482. Approximately 152 lymph nodes were detected with MR imaging. Of these, 28 were thought to be malignant, and 124 were thought to be benign, although 32 were malignant and 120 were benign according pathological results. The ratio of benign lymph node intensity value to normal esophagus intensity value was 0.73 ± 0.3. The ratio of malignant lymph node intensity value to normal esophagus intensity value ratio was 2.03 ± 0.4. According to these results, the sensitivity of MR was 81.3%, the specificity was 98.3%.Conclusion
We think that if motionless images can be obtained with MRI, we may be able to differentiate benign lymph nodes from malignant ones. 相似文献98.
Andi Utama Sigit Purwantomo Marlinang Diarta Siburian Rama Dhenni Rino Alvani Gani Irsan Hasan Andri Sanityoso Upik Anderiani Miskad Fardah Akil Irawan Yusuf Wenny Astuti Achwan Soewignjo Soemohardjo Syafruddin AR Lelosutan Ruswhandi Martamala Benyamin Lukito Unggul Budihusodo Laurentius Adrianus Lesmana Ali Sulaiman Susan Tai 《World journal of gastroenterology : WJG》2009,15(32):4028-4036
AIM: To identify the distribution of hepatitis B virus (HBV) subgenotype and basal core promoter (BCP) mutations among patients with HBV-associated liver disease in Indonesia.
METHODS: Patients with chronic hepatitis (CH, n =61), liver cirrhosis (LC, n = 62), and hepatocellular carcinoma (HCC, n = 48) were included in this study. HBV subgenotype was identified based on S or preS gene sequence, and mutations in the HBx gene including the overlapping BCP region were examined by direct sequencing.
RESULTS: HBV genotype B (subgenotypes B2, B3, B4, 85 and B7) the major genotype in the samples, accounted for 75.4%, 71.0% and 75.0% of CH, LC and HCC patients, respectively, while the genotype C (subgenotypes C1, C2 and C3) was detected in 24.6%, 29.0%, and 25.0% of CH, LC, and HCC patients, respectively. Subgenotypes B3 (84.9%) and C1 (82.2%) were the main subgenotype in HBV genotype B and C, respectively. Serotype adw2 (84.9%) and adrq+ (89.4%) were the most prevalent in HBV genotype B and C, respectively. Double mutation (A1762T/G1764A) in the BCP was significantly higher in LC (59.7%) and HCC (54.2%) than in CH (19.7%), suggesting that this mutation was associated with severity of liver disease. The T1753V was also higher in LC (46.8%), but lower in HCC (22.9%) and CH (18.0%), suggesting that this mutation may be an indicator of cirrhosis.
CONCLUSION: HBV genotype B/B3 and C/C1 are the major genotypes in Indonesia. Mutations in BCP, such as A1762T/G1764A and T1753V, might have an association with manifestations of liver disease. 相似文献
METHODS: Patients with chronic hepatitis (CH, n =61), liver cirrhosis (LC, n = 62), and hepatocellular carcinoma (HCC, n = 48) were included in this study. HBV subgenotype was identified based on S or preS gene sequence, and mutations in the HBx gene including the overlapping BCP region were examined by direct sequencing.
RESULTS: HBV genotype B (subgenotypes B2, B3, B4, 85 and B7) the major genotype in the samples, accounted for 75.4%, 71.0% and 75.0% of CH, LC and HCC patients, respectively, while the genotype C (subgenotypes C1, C2 and C3) was detected in 24.6%, 29.0%, and 25.0% of CH, LC, and HCC patients, respectively. Subgenotypes B3 (84.9%) and C1 (82.2%) were the main subgenotype in HBV genotype B and C, respectively. Serotype adw2 (84.9%) and adrq+ (89.4%) were the most prevalent in HBV genotype B and C, respectively. Double mutation (A1762T/G1764A) in the BCP was significantly higher in LC (59.7%) and HCC (54.2%) than in CH (19.7%), suggesting that this mutation was associated with severity of liver disease. The T1753V was also higher in LC (46.8%), but lower in HCC (22.9%) and CH (18.0%), suggesting that this mutation may be an indicator of cirrhosis.
CONCLUSION: HBV genotype B/B3 and C/C1 are the major genotypes in Indonesia. Mutations in BCP, such as A1762T/G1764A and T1753V, might have an association with manifestations of liver disease. 相似文献
99.
G Zifarelli A Liantonio A Gradogna A Picollo G Gramegna M De Bellis AR Murgia E Babini D Conte Camerino M Pusch 《British journal of pharmacology》2010,160(7):1652-1661
Background and purpose:
ClC-K kidney Cl− channels are important for renal and inner ear transepithelial Cl− transport, and are potentially interesting pharmacological targets. They are modulated by niflumic acid (NFA), a non-steroidal anti-inflammatory drug, in a biphasic way: NFA activates ClC-Ka at low concentrations, but blocks the channel above ∼1 mM. We attempted to identify the amino acids involved in the activation of ClC-Ka by NFA.Experimental approach:
We used site-directed mutagenesis and two-electrode voltage clamp analysis of wild-type and mutant channels expressed in Xenopus oocytes. Guided by the crystal structure of a bacterial CLC homolog, we screened 97 ClC-Ka mutations for alterations of NFA effects.Key results:
Mutations of five residues significantly reduced the potentiating effect of NFA. Two of these (G167A and F213A) drastically altered general gating properties and are unlikely to be involved in NFA binding. The three remaining mutants (L155A, G345S and A349E) severely impaired or abolished NFA potentiation.Conclusions and implications:
The three key residues identified (L155, G345, A349) are localized in two different protein regions that, based on the crystal structure of bacterial CLC homologs, are expected to be exposed to the extracellular side of the channel, relatively close to each other, and are thus good candidates for being part of the potentiating NFA binding site. Alternatively, the protein region identified mediates conformational changes following NFA binding. Our results are an important step towards the development of ClC-Ka activators for treating Bartter syndrome types III and IV with residual channel activity. 相似文献100.
summary The aim of this study was to determine the bone density in the designated implant sites using computerized tomography (CT), the fastening torque values of dental implants, and the implant stability values using resonance frequency analysis. Further aim was to evaluate a possible correlation between bone density, fastening torque and implant stability. Eighty‐five patients were treated with 158 Brånemark System implants. CT machine was used for preoperative evaluation of the jawbone for each patient, and bone densities were recorded in Hounsfield units (HU). The fastening torque values of all implants were recorded with the OsseoCare equipment. Implant stability measurements were performed with the Osstell machine. The average bone density and fastening torque values were 751·4 ± 256 HU and 39·7 ± 7 Ncm for 158 implants. The average primary implant stability was 73·2 ± 6 ISQ for seventy implants. Strong correlations were observed between the bone density, fastening torque and implant stability values of Brånemark System TiUnite MKIII implants at implant placement (P < 0·001). These results strengthen the hypothesis that it may be possible to predict and quantify initial implant stability and bone quality from pre‐surgical CT diagnosis. 相似文献