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41.
In order to know the prevalence and risk factors for coinfections by human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) among injecting drug users (IDUs), a cross-sectional study was carried out in two prisons of the province of Cantabria, northern Spain. Three hundred and sixty-two IDU inmates were recruited. All inmates were interviewed and their blood tested for HIV, HBV and HCV. Crude and multiple risk factor adjusted for (by polychotomous logistic regression) odds ratios were calculated. Prevalence of HBV-HCV coinfection (42.5%) was higher than HIV-HBV-HCV coinfection (37.3%), whereas monoinfections were very uncommon (overall: 13%). Long-term injectors and reincarceration were the foremost risk factors for both coinfections, showing a trend between the degree of association and the number of viruses infecting a patient. No significant relationship between coinfection status and sexual practices was observed. The results related to coinfections are consistent with previous studies of prevalence and risk factors for HIV, HBV and HCV, in indicating that the high rates of coinfections among IDU inmates emphasise the need to harm-reduction policy across prisons in Spain.  相似文献   
42.
Until recently the only way to rescue masked epitopes in routinely processed surgical pathological material was enzymatic digestion. The use of heat for antigen retrieval, first by microwave irradiation, represents an important breakthrough in immunohistochemistry. With the acceptance of microwave oven pretreatment, various modified techniques and alternative heating methods have also been proposed. Wet autoclave pretreatment for tissue proteolysis is a highly reliable alternative to the microwave antigen retrieval technique. It provides uniform heating of the slides, hence an even enhancement of staining intensity in a variety of formalin-sensitive antigens, and it also offers consistent interlaboratory results. The method has been introduced in routine diagnostic immunohistochemistry for the detection of estrogen-and progesterone receptors, L26-, Ki-67- and bcl-2 antigens and variable types of cytokeratins (1/5/10/11, 8, 13, 19). Experimentally, wet autoclaving can be used very successfully for the immunophenotyping of p53 and mdm2 expression, for the detection of adhesion molecules (CD44, integrins) and some anti-inflammatory molecules (annexins), among others. It has produced a substantial improvement in the visualisation of silver-stained nucleolar organizer regionsassociated proteins (AgNORs) in routine paraffin sections and along with modified silver staining and standardized AgNOR parameters assessed by image analysis. Wet autoclaving-based AgNOR staining has been proposed by a European multicentric study group as the standardized method for AgNOR analysis in archival material.  相似文献   
43.
Lipoma of the uterus is a rare condition usually developing in postmenopausal women. Clinical symptoms and physical signs are similar to those found in leiomyomas. The histiogenesis of these lesions is still unclear. We report a case of a pure intramural lipoma of the uterus illustrating characteristic morphological and histological findings. Additional immunohistochemical studies underline the lipomatous but not leiomyomatous nature of the tumor.  相似文献   
44.
Summary We report 137 recurrent supratentorial astrocytomas. The primary tumours diagnosed on the basis of a grading system with three stages were 72 astrocytomas I and 65 astrocytomas II. In the first group 14% of the recurrences were not changed, 55.5% became astrocytomas II, and 30.5% became glioblastomas. In the second group 55.4% were unchanged, and 44.6% became glioblastomas. The postoperative intervals until reintervention or death were statistically examined. It seems that the recurrence time chiefly depends on the nature of the primary tumour. The transformation of an astrocytoma I to a glioblastoma takes longer than the transformation of an astrocytoma II into a glioblastoma. In about two thirds of all astrocytomas an increase of malignancy is to be expected. From the histological picture it is not possible in an individual case to predict the likelihood or speed of malignant change. With regard to the effect of irradiation the authors conclude that radiotherapy most probably does not produce malignancy.The authors wish to express their gratitude to the founder and organizer of the Institute of Neurosurgery in Budapest, Prof. Dr. L. Zoltán (), for his promotion of these investigations.  相似文献   
45.
Background. To know the temporary tendency in the mortality due to breast cancer in Castilla-La Mancha (CLM, Spain) between 1975 and 1998. Patients and methods. The mortality data are from the Registry of Mortality of CLM. Crude and standardized mortality rates are calculated. In order to evaluate the tendency, we use the Poisson’s log- linear model. We have calculated the accumulated rate to die and the accumulated risks to die and to become ill. Results. Between 1975 and 1998, 2.44% of all deaths in CLM women were consequence of a breast cancer. The crude rate increased from the 14.55 by 100,000 in 1975 to 25.23 by 100,000 in 1998, with an annual average increase of 1.49%. The average age of death increased until the 67 years old in 1998 as opposed to the 59 years old of 1975. The risk of dying of a breast cancer increased in the period from 1.4% in 1975 to 2.34% in 1998. Conclusion. Mortality by breast cancer has raised until 1993, when it begun to decrease. In general, women with breast cancer die elderly, and young women have increased risk to fall ill.  相似文献   
46.
Twelve laryngeal squamous cell carcinoma cases (7 laryngeal and 5 hypopharyngeal cancer; 15 samples) were analysed by immunohistochemistry for the expression of invasion markers CD44v6/v3, NM23 and matrix metalloproteinase, MMP2. The laryngeal epithelium showed CD44v6+v3+NM23- /MMP2- phenotype. When tumors were grouped into TNM categories the phenotype of the T2 and T3 tumors was similar, characterised by decreased CD44v3+ and lack of MMP2 expressions. Meanwhile the NM23 expression was more frequent in T3 tumors. In T4 stage the frequency of NM23 and MMP2 positive cases increased (5/6 and 4/6, respectively) but there was no correlation with the appearence of lymph node metastasis. Comparison of the phenotype of laryngeal and hypopharyngeal tumors, irrespective of the TNM stages, revealed characteristic differences: T2 stage laryngeal tumors showed decreased CD44v3 and occasional NM23 and MMP2 positivity, while in T3 stage these tumors were characterised by increased frequency of NM23 positivity. The phenotype of the hypopharyngeal tumors was significantly different with a high frequency of MMP2 positive cases (5/6) and NM23+1ow CD44v3+ phenotype. The sharp differences in the phenotypes of laryngeal and hypopharyngeal carcinomas were connected to the differences in their invasive capacity unlike to the size of the tumors, since the T4 stage hypopharyngeal tumors had a significantly smaller size than laryngeal ones, even at lower stages. This work was supported by the Hungarian Ministry of Welfare: ETT No: T-11-100/93  相似文献   
47.
Both marijuana and retroviruses impair natural killer (NK) cell functions, but no data on their simulataneous effects are available. Similarities to human AIDS induced by Friend leukemia complex (FLO and its helper Rowson-Parr virus (RPV) provides a mouse model to study drug-virus action. Leukemia susceptible BALB/c and resistant C57BL/6 mice were infected, then at time intervals their nylon wool-separated splenocytes were exposed to tetrahydrocannabinol (THC) for 3h. Natural killer cell activity against Yac-1 cells was assayed by 51Cr-release for 4 and 18h. Recovery of splenocytes was found to be suppressed by FLC, but in BALB/c only by RPV. After a transient enhancement in C57BL/6 by FLC, NK cell activity of both mice became suppressed early (2 to 4 days), normalized subsequently and enhanced late (11 to 14 days) postinfection. A moderate increase in BALB/c, no change in C57BL/6 were induced by low (1-2.5 g/ml) THC doses. NK cell activity of BALB/c became suppressed exponentially by higher (5-10 g/ ml) THC doses in 18h as compared to 4h assays, while its proportional and moderate impairment was seen in C57BL/6. The magnitude of NK cell activity of infected mice was determined by THC: enhancement or impairment followed those of untreated, infected counterparts on the level of THC-treated cells. Low doses hardly, high doses additively influenced NK cells of infected BALB/c. THC slightly affected very early and late enhancement in NK cell activity of FLC infected C57BL/6, but augmented RPV induced suppression late in 18h assays. Genetic factors similar to endotoxin resistance, altered cytokine profile might determine these effects. Similar phenomena in humans might result in earlier manifestation of AIDS.  相似文献   
48.
Introduction This phase II study investigated the anti-tumour activity and toxicity of CPT-11 (250 mg/m2 i.v. infusion over 60 minutes) administered every 2 weeks as second-line chemotherapy in patients with advanced colorectal cancer (CRC). Material and methods Patients (n=63) with histology diagnosis of advanced CRC and proven resistance to previous fluoropyrimidine therapy were enrolled. Results A total of 510 CPT-11 cycles were administered, with a mean of 8 cycles per patient (range: 1–32). The median relative dose intensity was 93%. Partial response (PR) was obtained in 11 patients (17.5%; 95%CI: 8.1%–26.7%) and 29 patients (46.0%) showed stable disease (clinical benefit of 63.5%). The median duration of response was 6.8 months (95%CI: 6.1–7.5 months), median survival was 8.8 months (95%CI: 6.3–11.5 months) and median time to disease progression was 4.5 months (95%CI: 3.9–5.0 months). Overall, this schedule of CPT-11 chemotherapy was well tolerated by the patient. Neutropenia was the most frequent grade 3/4 haematological toxicity (20.6% of patients and 4.1% of cycles). Neutropenia with concurrent fever or infection occurred in 7 patients (11.1%). Late onset diarrhoea was the most frequent grade 3/4 non-haematological toxicity (19.0% of patients and 2.3% of cycles). Other, lower-incidence, toxicities were anaemia, fever, infection, mucositis, nausea and vomiting. There were no toxic deaths. Conclusions We found that CPT-11, administered as 250 mg/m2 i.v. infusion over 60 minutes every 2 weeks, was active and well tolerated schedule in the second-line chemotherapy of advanced CRC patients. This bi-weekly scheme could be used as an alternative to the weekly or the every-three-week schedule as well as in combined therapies with other chemotherapeutic agents for the treatment of advanced, metastatic, CRC.  相似文献   
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