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981.

Background

Literature on the spectrum of opportunistic disease in human immunodeficiency virus (HIV)-infected patients from developing countries is sparse. The objective of this study was to document the spectrum and determine the frequency of various opportunistic infections (OIs) and non-infectious opportunistic diseases, in hospitalised HIV-infected patients from north India.

Methods

One hundred and thirty five consecutive, HIV-infected patients (age 34 ± 10 years, females 17%) admitted to a tertiary care hospital in north India, for the evaluation and management of an OI or HIV-related disorder between January 2000 and July 2003, were studied.

Results

Fever (71%) and weight loss (65%) were the commonest presenting symptoms. Heterosexual transmission was the commonest mode of HIV-acquisition. Tuberculosis (TB) was the commonest OI (71%) followed by candidiasis (39.3%), Pneumocystis jiroveci pneumonia (PCP) (7.4%), cryptococcal meningitis and cerebral toxoplasmosis (3.7% each). Most of the cases of TB were disseminated (64%). Apart from other well-recognised OIs, two patients had visceral leishmaniasis. Two cases of HIV-associated lymphoma were encountered. CD4+ cell counts were done in 109 patients. Majority of the patients (82.6%) had CD4+ counts <200 cells/μL. Fifty patients (46%) had CD4+ counts <50 cells/μL. Only 50 patients (37%) received antiretroviral therapy. Twenty one patients (16%) died during hospital stay. All but one deaths were due to TB (16 patients; 76%) and PCP (4 patients; 19%).

Conclusions

A wide spectrum of disease, including both OIs and non-infectious opportunistic diseases, is seen in hospitalised HIV-infected patients from north India. Tuberculosis remains the most common OI and is the commonest cause of death in these patients.
  相似文献   
982.
Effects of temperature on granulocyte preservation   总被引:1,自引:0,他引:1  
McCullough  J; Wieblen  BJ; Peterson  PK; Quie  PG 《Blood》1978,52(2):301-310
With the increasing use of granulocyte transfusion it is becoming important to determine if granulocytes can be preserved for a few days. If so, the optimum storage conditions must be identified. We studied the function in vitro of granulocytes collected as they would be for transfusion by continuous-flow centrifuge leukapheresis (CFCL) and filtration leukapheresis (FL). Granulocytes collected by CFCL maintained normal ability to phagocytose and kill bacteria after 48 hr and normal chemotaxis after 24 hr of storage at 20 degrees--24 degrees C. Neither 1 degrees--6 degrees C nor 37 degrees C were as effective in preserving chemotactic response. Agitation of the granulocyte suspension during storage caused reduced bacterial killing and chemotaxis. Granulocytes collected by FL functioned very poorly after 24 hr storage at all temperatures studied. These studies suggest that it may be possible to store CFCL granulocytes at 20 degrees--24 degrees C for 24 hr. FL granulocytes should not be stored at all.  相似文献   
983.
Huh  MM; Schick  BP; Schick  PK; Colman  RW 《Blood》1988,71(6):1693-1702
Coagulation factor V (FV) has been shown to be synthesized in both the liver and megakaryocytes. We now present evidence that FV can be covalently crosslinked by an enzyme originating from megakaryocytes to form polymeric multimers of factor V. The guinea pig megakaryocyte enzyme appears to be factor XIIIa since the FV-crosslinking activity (1) had an absolute requirement for Ca++, (2) was completely inhibited by iodoacetamide, 5,5'-dithiobis- (2-nitrobenzoic acid), p- chloromercuribenzene sulfonic acid, and N-ethylmaleimide, all known alkylators of the thiol group at the active site of the factor XIIIa, (3) was blocked by known pseudoamine donor substrates of factor XIIIa including dansylcadaverine and putrescine, and (4) could be directly demonstrated in the guinea pig megakaryocyte lysate by a specific activity staining procedure. No tranglutaminase was detected in guinea pig megakaryocytes in contrast to red cells and liver. A similar pattern of covalent crosslinking of human FV by purified activated human plasma factor XIII was also demonstrated. Analysis of the crosslinked products of FV formed by the guinea pig enzyme by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) indicates the formation of intermediate as well as higher molecular weight polymers, suggesting that the crosslinking is a stepwise polymerization process.  相似文献   
984.
Cytogenetics of childhood T-cell leukemia   总被引:6,自引:0,他引:6  
The karyotypes of 57 cases of childhood T-cell acute lymphoblastic leukemia (ALL) were analyzed to establish the cytogenetic profile in this disease. Three questions were of particular interest. Do the chromosomal changes in T-cell ALL preferentially affect bands where genes encoding the T-cell receptor for antigen (TCR) have been mapped? Do alterations involving the TCR gene regions appear with any notable frequency in B-progenitor ALL? Do chromosomal abnormalities in this disease relate to stage of T-cell ontogeny? A relatively high proportion of cases (65%) had a pseudodiploid karyotype at presentation, the majority (58%) characterized by a translocation. The overall frequency of translocations was 44%, comparable to that among all banded cases of ALL seen in our laboratory. Hypodiploidy and hyperdiploidy were exceedingly rare (only four of 57 cases); 16 cases (28%) had apparently normal karyotypes. In half the cases with a translocation (14 of 24), the breakpoints were in regions to which the alpha and beta chain TCR genes have been mapped. Chromosomal breakpoints that were consistently observed in the vicinity of TCR gene loci were 7q32-q36 (TCR beta chain; n = 8), 14q11-q13 (TCR alpha chain; n = 6); other frequent breakpoints were 9p13-pter (n = 8) and 6q15-qter (n = 9). Chromosomal alterations occurred near TCR gene loci significantly more often in T-cell cases than in a comparison group of 335 patients with B-cell precursor ALL (26% v 1.5%, P = .0001). Stage I thymocyte development (CD7+, CD2+, CD5+, CD1-, CD3-, CD4-, CD8-) was noted in 23 cases, stage II (CD7+, CD2+, CD5+, CD1+, CD3-, CD4 +/-, CD8 +/-) in 25 cases, and stage III (CD9+, CD2+, CD1-, CD5+, CD3+, and either CD4+ or CD8+) in nine cases. The only statistically significant associations between cytogenetic findings and T-cell ontogeny were a higher frequency of normal karyotypes in cases with stage I thymocytes, and of pseudodiploidy in stage II cases. There was no apparent relationship between particular translocations and level of thymocyte maturation. Our findings indicate that most children with T-cell ALL have pseudodiploid karyotypes, although a surprisingly high percentage lack demonstrable abnormal clones. Specific chromosomal changes do not appear to be related to discrete stages of T-cell ontogeny as defined in this study, but they occur preferentially in bands containing TCR genes.  相似文献   
985.
The replication terminator protein (RTP) of Bacillus subtilis is a dimer with a monomeric molecular mass of 14.5 kDa. The protein terminates DNA replication at a specific binding site. Although the protein has been crystallized and its crystal structure has been solved, the lack of an in vitro replication system in B. subtilis has been a serious impediment to the analysis of the mechanism of action of this protein. We have discovered that the protein is functional in the Gram-negative bacterium Escherichia coli in vivo and in vitro. RTP blocked replication forks initiated from a ColE1 replication origin at the cognate DNA-binding site (BS3) in a polar mode. The protein did not block rolling circle replication initiated from the pT181 origin in cell extracts of Staphylococcus aureus. RTP antagonized the helicase activity of DnaB but not that of helicase II of E. coli. Thus, RTP functioned as a polar contrahelicase blocking a helicase that participates in symmetric DNA replication but it did not impede rolling circle replication nor the action of a helicase involved in DNA repair.  相似文献   
986.
细胞间黏附分子与胃癌侵袭、转移关系的研究进展   总被引:1,自引:0,他引:1  
细胞间黏附分子-1(intercellularadhesionmolecule-1,ICAM-1)是体内重要的细胞活性分子,不仅参与了机体免疫过程及炎症反应,而且还通过与其相应配体的结合,介导癌细胞与不同细胞、基质的黏附,最终使癌细胞逃避免疫监视,利于侵袭转移.近年来,对ICAM-1与恶性肿瘤侵袭转移关系的研究已成为研究热点,其在肿瘤侵袭转移中的作用日益受到众多学者的重视.现就其近年的文献从ICAM-1的结构、生物学特征、在胃癌组织中的表达及作用机制等几个方面作一综述.  相似文献   
987.
A case of epithelial tissue tumour on the body of an adult grey mullet Mugil cephalus L. is reported. The gross morphology revealed reddish white polyp-like tumorous growth on right side attached to the muscles of the caudal peduncle region. Histologically, the tumourous growth was characterised by highly anaplastic epitheloid cells intermingled with fibroblasts, blood vessels and few necrotic cells, probably originating from skin tissue. There was no internal metastasis as observed from histology of other tissues. The tumour was diagnosed as squamous cell carcinoma with unknown etiology.  相似文献   
988.
Due to over increasing demand, huge collection and habitat destruction wild gingers having future medicinal potential are on way to extinction. Conservation of germplasm in clonal repositories by conventional methods is very difficult due to greater susceptibility to rhizome-rot disease. In vitro conservation strategy has so far been made for a few species. Thus the present study aiming at in vitro conservation of nine species and subsequent stability assessment of plantlets using efficient molecular markers assumes significance. Murashige and Skoog media with different growth regulators were standardized for conservation. Conservation period without sub culturing for all species was in a range of 8–12 months. Survival was more than 80 % up to three years. On the basis of 25 random amplified polymorphic DNA and ten Inter simple sequence repeat primers no significant variation was observed among the in vitro conserved and control plants. The micropropagated plants are morphologically and genetically uniform when compared to their field grown mother plants. Thus, the report has immense potential towards the conservation of genetic resources for future breeding and improvement programme by continuous supply of genetically uniform plantlets.  相似文献   
989.
990.
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