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1.
A 29-year-old man who had been treated for acute anterior uveitis in a local medical office and observed for 1 month presented complaining of distorted vision in his left eye for 1 week. On ophthalmic examination, the anterior segment was relatively quiet with few cells. A posterior segment examination revealed cystoid macular edema and multiple splinter retinal hemorrhages. Results of all laboratory and imaging studies were negative, except for a positive HLA-B27 haplotype. Fluorescein angiography revealed massive leakage in the mid and late phase, consistent with chorioretinitis. Periocular corticosteroid injections and oral prednisolone were administered. The patient responded to the treatment well with subsequent resolution of chorioretinitis 2 months later. Although rare, chorioretinitis can occur in the setting of uveitis associated with HLA-B27 and seems to respond well to corticosteroid treatment.  相似文献   
2.
Purpose: Using different micropipettes for zona drilling and blastomere aspiration for embryo biopsy is prevalent at centers of preimplantation genetic diagnosis. The purpose of our study was to simplify the technique by using only one micropipette. Methods: In this animal model, ICR mouse embryos at the four-cell stage (n=446) were randomly allocated into two groups: a biopsied group (n=224) for blastomere aspiration and a control group (n=222) without micromanipulation. We used a drilling/biopsy micropipette to drill a hole in the zona by expulsion of acidified Tyrode’s solution and to aspirate the blastomere by gentle suction with the same micropipette and pull it out of the zona. One blastomere was biopsied from each embryo. Results: In all, 222 (99.1%) intact blastomeres were successfully biopsied from 224 embryos. Only two blastomeres were damaged during aspiration. The capacity for blastocyst development (92.4 vs 93.7%) was not different between the two groups, but the percentages of embryos hatching (51.8 vs 18.0%) and hatched (29.9 vs 8.1%) were significantly higher in the biopsied group than in the control group. Conclusions: This simplified technique of embryo biopsy is safe and highly efficient for obtaining blastomeres for preimplantation genetic diagnosis and may also facilitate hatching of the blastocysts.  相似文献   
3.
The methane-rich, hydrothermally heated sediments of the Guaymas Basin are inhabited by thermophilic microorganisms, including anaerobic methane-oxidizing archaea (mainly ANME-1) and sulfate-reducing bacteria (e.g., HotSeep-1 cluster). We studied the microbial carbon flow in ANME-1/ HotSeep-1 enrichments in stable-isotope–probing experiments with and without methane. The relative incorporation of 13C from either dissolved inorganic carbon or methane into lipids revealed that methane-oxidizing archaea assimilated primarily inorganic carbon. This assimilation is strongly accelerated in the presence of methane. Experiments with simultaneous amendments of both 13C-labeled dissolved inorganic carbon and deuterated water provided further insights into production rates of individual lipids derived from members of the methane-oxidizing community as well as their carbon sources used for lipid biosynthesis. In the presence of methane, all prominent lipids carried a dual isotopic signal indicative of their origin from primarily autotrophic microbes. In the absence of methane, archaeal lipid production ceased and bacterial lipid production dropped by 90%; the lipids produced by the residual fraction of the metabolically active bacterial community predominantly carried a heterotrophic signal. Collectively our results strongly suggest that the studied ANME-1 archaea oxidize methane but assimilate inorganic carbon and should thus be classified as methane-oxidizing chemoorganoautotrophs.  相似文献   
4.
5.
The acinus-mimicking microfluidic chip, which simulates the in vivo condition of the liver, was developed and reported in this paper. The gradient microenvironment of the liver acinus is replicated within this proposed microfluidic chip. The advantage of this acinus-mimicking chip is capable of adjusting the concentration gradient in a relatively short period of time at around 10 s. At the same instance the non-linear concentration gradient can be presented in the various zones within this microfluidic chip. The other advantage of this proposed design is in the convenience of allowing the direct injection of the cells into the chip. The environment within the chip is multi-welled and gel-free with high cell density. The multi-row pillar microstructure located at the entrance of the top and bottom flow channels is designed to be able to balance the pressure of the perfusion medium. Through this mechanism the shear stress experienced by the cultured cells can be minimized to reduce the potential damage flow from the perfusion process. (3)The fluorescence staining and the observations of the cell morphology verify the life and death of the cells. The shear stress experienced by the cells in the various zones within the chip can be effectively mapped. The serum glutamic oxaloacetic transaminase (SGOT) collected from the supernatants was used to determine the effects of the degassing process and the shear stress of the medium flow on the cultured cells.  相似文献   
6.
BACKGROUND AND PURPOSE: This study compared the neonatal outcome between infants born after in vitro fertilization (IVF) and after natural conception at National Taiwan University Hospital. METHODS: All medical records of women who underwent IVF and gave birth at our hospital from January 1995 to December 1996 were reviewed. The charts of their offspring were also reviewed. We compared the neonatal outcome of infants born after IVF with that of infants born after natural conception. Neonatal outcome was evaluated based on preterm birth, very low birth weight (VLBW), perinatal morbidity, and neonatal mortality. RESULTS: A total of 75 women underwent IVF and gave birth to a total of 100 live newborns and two fetuses with intrauterine death during the 2-year study period. Among these newborns, the prevalence of preterm birth was 28%, of perinatal morbidity was 17%, and of neonatal mortality was 3%, which were significantly higher than those among the 7,736 neonates born after natural conception. However, the rate of VLBW was similar between the two groups. The rate of preterm birth for twin pregnancies were higher than that for singleton pregnancies in both groups. CONCLUSION: This study showed that infants born after IVF had a higher risk of preterm birth and higher perinatal morbidity and neonatal mortality.  相似文献   
7.
Recently, several investigators have emphasized that damagingthe membrane of spermatozoa by compressing the mid-piece orcutting the mid-portion of the tail prior to injection yieldsbetter results than using motile spermatozoa in intracytoplasmicsperm injection (ICSI). Here we report our experience usinga modified immobilization technique of dissecting the tail ofthe spermatozoon at the tip in 78 cycles on 60 patients. In55 treatment cycles purely using this modified technique, 468mature oocytes were injected. A total of 35 oocytes (7.5%) wereinjured. Of the intact oocytes, 282 (65.1%) were normally fertilizedand 266 (94.3%) subsequently cleaved. A single pronucleus wasobserved in 16 (3.7%) oocytes, and three pronuclei were notedin 11 (2.5%) oocytes. Embryo transfers were performed in 54cycles, and 18 women (32.7%) achieved clinical pregnancies.In 23 cycles, we compared the effects of these three immobilizationtechniques on the sibling oocytes obtained from the same patientregarding normal fertilization, abnormal fertilization, andembryo cleavage and quality. The results were comparable amongthem. Seven pregnancies (30.4%) were achieved in this series.Dissecting a sperm tail at the tip is easily and quickly performedand achieves permanent immobilization. Compression of the mid-pieceis also easy, but usually takes several actions to achieve immobilization.Cutting the tail at the mid-portion requires more skill. Therefore,dissecting the tail of the spermatozoon at the tip may providean alternative method to immobilize the spermatozoon permanentlyprior to ICSI.  相似文献   
8.
Women who had stage III-IV endometriosis and who were nulliparous or who had delivered no more than two children were much more likely to develop tubo-ovarian abscesses than those without endometriosis.  相似文献   
9.
BACKGROUND: The aim of this study was to investigate haploidization of somatic cell nuclei in non-enucleated mature oocytes regarding spindle formation, chromosomes and developmental potential. METHODS: Mouse cumulus cells were injected into metaphase II oocytes. Some injected oocytes were examined for morphological changes of chromosomes and the spindle immediately, and at 30 min, 1 h or 2 h after the injections. The remaining oocytes were activated by Sr(2+) after various incubation periods and observed for formation of a second polar body and pseudo-polar body. Cytogenetic analysis was performed for some of the resulting zygotes. The progress to blastocysts in vitro and the possibility of conception in vivo were assessed. RESULTS: Immediately after injection, the cumulus cell nucleus was still in interphase without spindle formation. The occurrence of premature chromosome condensation (PCC) and spindle formation increased as the incubation time increased. The percentages of activated oocytes increased with the incubation time after nuclear transfer, but the difference was not significant between 1 (58%) and 2 h (62%). The incidence of chromosomal aberrations was high for the derived embryos. Development in vitro was poor, and no procreation of pups occurred after transfer of the 324 embryos. CONCLUSIONS: The PCC and spindle formation induced by cumulus cell nuclei in mature oocytes was time dependent, as was the chance for successful activation. The chromosomal abnormalities from segregation errors presented one obvious cause, apart from the potential epigenetic defects, of developmental failure of the semi-cloned embryos.  相似文献   
10.
BACKGROUND AND PURPOSE: Human papillomavirus (HPV) infection is associated with increased incidence and severity of HPV-related cervical dysplasia and cervical cancer in women with human immunodeficiency virus (HIV) infection. This study examined the incidence of genital HPV infection in HIV-infected Taiwanese women and its relationship with cervical neoplasia. METHODS: This hospital-based, case-control study enrolled 31 consecutive HIV-seropositive women and 124 age-matched women who were free from HIV infection. Polymerase chain reaction (PCR) was used to distinguish high-risk (types 16, 18, 31, 33, 52 and 58) and low-risk HPV (types 6 and 11). The occurrence of genital HPV infection was compared between women with and without HIV infection. In addition, CD4 lymphocyte counts were determined by flow cytometry and Papanicolaou test was done in women with HIV infection. RESULTS: HPV and Papanicolaou test were done soon after the diagnosis of HIV infection. HIV seropositive women had a significantly greater high-risk HPV infection rate (48.4%; 15/31) than women without HIV infection (20.2%; 25/124; odds ratio, 3.71; p = 0.001). However, the prevalence of cervical intraepithelial neoplasia was similar between women with and without HIV infection. The CD4 lymphocyte counts in HIV-seropositive women were similar between those with and without genital HPV infection. CONCLUSIONS: The risk of genital HPV infection was significantly increased in HIV-infected women. Due to the association between high-risk HPV infection and the development of cervical dysplasia and cervical cancer, regular follow-up of Papanicolaou test is necessary in these women.  相似文献   
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