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1.
Gonadal steroid levels were determined in the ovary ofSalamandra salamandra infraimmaculataduring the reproductive cycle in populations from a xeric region in northern Israel. Varying proportions of previtellogenic and vitellogenic oocytes were present throughout the year, and mature oocytes were present in winter and spring. The numbers of mature oocytes were greater between December and April, after parturition. The levels of 17β-estradiol and testosterone rose during oocyte vitellogenesis and maturation. Levels of progesterone and 17α-hydroxy progesterone appeared to be related to the level of vitellogenesis. Gravid females contained greater quantities of all four steroids than did nongravid females.  相似文献   
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We previously have shown that adenovirus type 5 E4orf4 protein associates with protein phosphatase 2A (PP2A) and induces apoptosis in transformed cells in a p53-independent manner. Here we show that the interaction between E4orf4 and PP2A is required for induction of apoptosis by the viral protein. This conclusion is supported by a mutation analysis of E4orf4 protein, showing a correlation between the ability to bind PP2A and to induce apoptosis, and by the observation that transfection of an antisense construct of the PP2A-B55 subunit reduces expression of the PP2A-B55 subunit and inhibits induction of apoptosis by E4orf4, but not by p53. The mutant analysis also indicates that even a low level of interaction with PP2A is sufficient to initiate the E4orf4 apoptotic pathway. In addition, E4orf4 inhibits cellular transformation by various oncogenes, and this function is coupled to its ability to induce apoptosis. Furthermore, expression of oncogenes in primary cell cultures sensitizes these cells to induction of apoptosis by E4orf4. Our results suggest that E4orf4 is a potentially useful tool for cancer gene therapy.  相似文献   
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Myocardial injury, developed after a period of ischemia/reperfusion (I/R) results in the destruction of functional heart tissue, this being replaced by scar tissue. Intracellular signaling pathways mediating cardiomyocyte death are partially understood and involve the activation of Ras. p38-MAPK, JNK and Mst-1 are downstream effectors of Ras protein. We hypothesized that S-farnesylthiosalicylic acid (FTS), a synthetic small molecule that detaches Ras from the inner cell membrane, consequently inhibiting Ras activity, reduces I/R myocardial injury in vitro and in vivo.Wistar rat hearts were isolated, mounted on the Langendorff apparatus and subjected to ischemia (30 min, 37 °C) and reperfusion. During the reperfusion period, the hearts were perfused with FTS (1 μM) solution or control buffer. Left anterior descending (LAD) ligation and subsequent reperfusion was performed in two groups of Wistar rats. Rats received 5 mg/kg FTS or PBS according to two protocols: (A) FTS or PBS were administered daily 7 days prior, immediately before and 14 days (every other day) after LAD occlusion or (B) every other day for 14 days post-I/R. Hearts from FTS-treated rats (Langendorff) and FTS-treated rats (protocol A) showed a significant improvement in myocardial performance and smaller scar tissue compared with the PBS group. Infarct size in the FTS-treated group was 12.7 ± 2% vs. 23.7 ± 4% in the PBS-treated (in vitro) group and 17.3 ± 2.5% vs. 36 ± 7% compared with control I/R rats (in vivo) p < 0.05. These effects may be associated with the down regulation of JNK as a short-term effector and with Mst-1 in the long-term remodeling process.  相似文献   
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Microorganisms must sense their environment and rapidly tune their metabolism to ambient conditions to efficiently use available resources. We have identified a gene encoding a response regulator, NblR, that complements a cyanobacterial mutant unable to degrade its light-harvesting complex (phycobilisome), in response to nutrient deprivation. Cells of the nblR mutant (i) have more phycobilisomes than wild-type cells during nutrient-replete growth, (ii) do not degrade phycobilisomes during sulfur, nitrogen, or phosphorus limitation, (iii) cannot properly modulate the phycobilisome level during exposure to high light, and (iv) die rapidly when starved for either sulfur or nitrogen, or when exposed to high light. Apart from regulation of phycobilisome degradation, NblR modulates additional functions critical for cell survival during nutrient-limited and high-light conditions. NblR does not appear to be involved in acclimation responses that occur only during a specific nutrient limitation. In contrast, it controls at least some of the general acclimation responses; those that occur during any of a number of different stress conditions. NblR plays a pivotal role in integrating different environmental signals that link the metabolism of the cell to light harvesting capabilities and the activities of the photosynthetic apparatus; this modulation is critical for cell survival.  相似文献   
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Aim.?Hysterolaparoscopy is the gold-standard procedure for mechanical evaluation of the female pelvic organs. However, it is invasive and potentially life-threatening. The purpose of the present study was to assess the value of an alternative, minimally invasive technique.

Method.?All consenting women who reached the stage of mechanical evaluation in their infertility work-up were invited to participate in the study. All underwent diagnostic hysteroscopy followed by hysterosalpingo contrast sonography (HyCoSy) performed in a single session on an outpatient basis. Patient clinical data were collected prospectively.

Results.?Twenty women participated in the study, 6 with primary infertility and 14 with secondary infertility. All procedures yielded satisfactory evaluation of the uterine cavity and uterine and ovarian structures, fallopian tube patency, and relationship between the fallopian tube fimbrial edges and the ovaries. All patients were discharged within 2 h; there were no complications during or after the procedure.

Conclusion.?The combination of hysteroscopy and hysterosalpingo contrast sonography (HyCoSy) can provide a comprehensive, functional and relatively non-invasive evaluation of the female pelvic organs.  相似文献   
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This article is devoted to the development and evaluation of the immunoblotting test system for serological diagnosis of African swine fever (ASF), based on the highly purified recombinant p30 of ASF virus (ASFV) strain Stavropol 01/08 (Stavropol 2008), representative of the ASFV currently circulating in the Russian Federation. The main project stages are as follows: (i) cloning of the central hydrophilic region of the ASFV gene CP204L (p30) into a prokaryotic vector; (ii) expression and chromatographic purification of the recombinant product p30 with thioredoxin and poly‐histidine site (p30e1_TrxA_6xHis); (iii) development of the immunoblotting test system (Rec p30‐IB) using the highly purified recombinant p30; and (iv) evaluation of Rec p30‐IB using sera and organ samples from domestic pigs and wild boars experimentally or naturally infected by ASFV. Testing of the Rec p30‐IB showed the diagnostic specificity and sensitivity of the assay to be 98.75% and 100.00%, respectively. High sensitivity of the Rec p30‐IB allowed the detection of ASFV‐specific antibodies in samples of organs of the immune system and blood sera, collected from domestic pigs and wild boars, starting from 6 to 8 days post‐infection, regardless of virus virulence, seroimmunotype and geographic origin of the samples (East Europe, South Europe, West Europe, Central and south‐east Africa).  相似文献   
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Objective. The primary objective of this study was to characterize the delivery outcome of parturients with congenital heart defects (CHD), from maternal and from neonatal perspectives.

Study design. A retrospective population-based study was conducted, covering a 13-year period (1989–2002) with an aggregate of 151 487 deliveries of all women with and without CHD. Maternal demographics, obstetrical and medical history, delivery outcome, and neonatal outcome were drawn from a computerized perinatal database.

Results. Sixty-seven women with CHD had 156 deliveries. The severity of CHD, based on the New York Heart Association (NYHA) classification, was I or II in 99.1% of the deliveries. CHD patients had significantly higher rates of labor induction and neonatal malformations. Maternal CHD was discovered as an independent risk factor associated with neonatal malformations (OR 2.10, 95% CI 1.18–3.72). No significant differences were noted between women with CHD and the controls regarding maternal morbidities and Apgar scores.

Conclusions. The labor outcome of CHD patients with NYHA classification I and II resembles that of non-CHD women in a tertiary center setting. Neonates of CHD mothers have higher rates of congenital malformations even among asymptomatic or mildly symptomatic mothers. A careful sonographic follow-up is warranted among all pregnancies of CHD patients.  相似文献   
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