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81.
82.
83.
Cholecystokinin-decreased food intake in rhesus monkeys 总被引:1,自引:0,他引:1
84.
Fugger EF; Black SH; Keyvanfar K; Schulman JD 《Human reproduction (Oxford, England)》1998,13(9):2367-2370
The world's first deliveries of normal babies after use of flow cytometric
separated human sperm cells (MicroSort) for preconception gender selection
are reported. Offspring were of the desired female gender in 92.9% of the
pregnancies. Most of these pregnancies and births were achieved after
simple intrauterine insemination.
相似文献
85.
Horne G; Jamaludin A; Critchlow JD; Falconer DA; Newman MC; Oghoetuoma J; Pease EH; Lieberman BA 《Human reproduction (Oxford, England)》1998,13(11):3045-3048
Insemination with donor spermatozoa is an integral part of infertility
treatment. For the last 3 years in our unit, intrauterine insemination with
donor spermatozoa (IUID) has been used in preference to vaginal
insemination. In this retrospective study, patients were offered an initial
course of five single intrauterine inseminations with cryopreserved donor
spermatozoa and treatment was then reviewed. A total of 389 patients
received 1465 inseminations. In all, 1119 cycles were monitored using
luteinizing hormone serum analyses and 346 cycles using the urine home test
kits. The clinical pregnancy rate per insemination for the cycles monitored
by the serum assay was 18.0% (202/1119) compared with the urine cycles
(13.7%, 46/346) (P <05). The pregnancy loss rate was not significantly
different (14.4%, 29/202 and 21.7%, 10/46) (serum and urine cycles
respectively). The viable clinical pregnancy rate was significantly higher
(P <03) for the serum cycles than for the cycles using the urinary
monitoring (15.5%, 173/1119 and 10.4%, 36/346 respectively). The cycles
monitored by serum assay had a significantly higher cumulative viable
clinical pregnancy rate (P <0001) of 70.2% after nine inseminations
compared with the urine monitored cycles of 54.8%. The majority of patients
opted for the serum cycles, with a minority self-selecting the urine cycles
mainly for travelling convenience. The explanation for the significant
differences between the viable clinical pregnancy rates per insemination
and the cumulative viable clinical pregnancy rates may be due to the
sensitivity of the urine home test kit or the patients' interpretation of
the result.
相似文献
86.
Recessively inherited L-DOPA-responsive parkinsonism in infancy caused by a point mutation (L205P) in the tyrosine hydroxylase gene 总被引:4,自引:0,他引:4
87.
Patrick Gonzalez De La Fuente Jean -Pierre Savineau Roger Marthan 《Pflügers Archiv : European journal of physiology》1995,429(5):617-624
The effect of thapsigargin (TG) and cyclopiazonic acid (CPA) on the mechanical activity of the rat pulmonary artery were investigated. In chemically (-escin)-skinned arterial strips, application of TG (0.1–1 M) or CPA (0.5–10 M) prior and throughout the loading procedure of the internal Ca2+ stores (0.3 M free Ca2+ ions for 8–10 min) concentration dependently inhibited the subsequent contractile response induced by noradrenaline (NA, 10 M) or caffeine (25 mM). In intact strips repeatedly incubated in a Ca2+-containing solution (2.5 mM for 10 min), followed by incubation in a Ca2+-free solution 12 min before NA-stimulation, TG and CPA not only inhibited the NA-induced contraction but also increased the tension which appeared during the exposure time to Ca2+. The two phenomena developed with similar time courses. The increase in tension during the readmission of Ca2+ ions was not antagonized by verapamil (10 M) or nifedipine (1 M) but was blocked by La3+ (50 M) and Co2+ (1 mM) ions. The amplitude of the verapamil-insensitive TG (or CPA)-induced contraction was dependent on the external [Ca2+] [0.1–10 mM, concentration for half maximal effect (EC50) =0.85 mM], not modified by the reduction of the external [Na+] (from 130 to 10 mM) and decreased by depolarization of the strip using K+-rich (30–120 mM) solutions. Under the latter condition, 38±9 and 83±4% reduction (n=5) was observed in the presence of 60 and 120 mM K+ respectively. This contraction was also concentration dependently inhibited by the tyrosine kinase inhibitors genistein (0.5–50 M) and tyrphostin (2–50 M). Sr2+ ions, which contracted both depolarized intact and skinned strips, failed to replace Ca2+ ions in the verapamil-insensitive contraction induced by TG or CPA (n=4). Finally, TG (1 M) and CPA (10 M) did not modify the pCa tension relationship in skinned strips (n=5). These results show that the main action of TG and CPA in rat pulmonary artery is to prevent the refilling of the internal Ca2+ store. TG and CPA also seem to facilitate a Ca2+ influx through a specific verapamil-insensitive pathway. The biophysical and molecular characteristics of this pathway remain to be elucitated, although it appears to involve a tyrosine kinase activity. 相似文献
88.
Claudio Gustavo Stefanoff Rocío Hassan Ana Carolina Gonzalez Luiz Ant?nio B Andrade Daniel G Tabak Sérgio Romano Ilana R Zalcberg 《Diagnostic molecular pathology》2003,12(2):79-87
We herein present a technical strategy to optimize DNA isolation from paraffin-embedded tissue (PET). This includes the choice of adequate buffers for proteinase K digestion and multiplex PCR amplifications for assessing the appropriateness of DNA extracts for subsequent PCR assays for detecting clonality. We found that the association of proteinase K digestion in nonionic buffer and subsequent extract dilutions accounted for 79% of successful amplifications. A final efficiency of 88% was achieved by additional organic extractions and/or re-extractions. Comparisons were carried out with control DNA extracts from fresh samples to assess the efficiency of each clonality assay. Immunoglobulin CDRIII rearranged region amplification was more efficient for pregerminal center B-cell lymphomas in contrast to CDRII rearrangement detection, which was more effective for germinal and postgerminal lymphomas. T-cell clonality detection by TCRgamma PCR was less efficient in PET samples than in fresh tissues showing that DNA integrity is more critical for TCR than for IGH amplification. Two inconclusive cases without phenotypic markers and two other atypical lymphoproliferations masked by reactive T cells were diagnosed as plasmablastic lymphomas and as monoclonal B-proliferations, respectively, due to IGH rearrangements. 相似文献
89.
M Salomonsson E Gonzalez P Westerlund A E Persson 《Acta physiologica Scandinavica》1991,142(2):283-290
The juxtaglomerular apparatus fulfils several important regulatory functions in the kidney, such as tubuloglomerular feedback (TGF) control and control of renin release. The macula densa (MD) cells sense the fluid load by perceiving the distal NaCl concentration via a Na-K-2Cl cotransport system in the luminal cell membrane. It has been proposed that macula densa cell activation may involve changes in intracellular cytosolic free calcium concentration ([Ca2+]i), as one link in the chain of events activating TGF or releasing renin. We therefore investigated the changes in the intracellular calcium concentrations with fura-2, using a video system, in macula densa cells, and compared them with the changes in the corresponding concentrations in the ascending limb of the loop of Henle (c-TAL). The results show that our technique for analysing intracellular cytosolic free calcium in isolated perfused tubules is valid for this purpose, and the Kd value obtained was similar to that found by Grynkiewicz et al. (1985). The intracellular cytosolic free calcium concentration was about 90 nM both in the macula densa and c-TAL cells, and the macula densa cell intracellular cytosolic free calcium concentration increased by about 20 nM when the tubular lumen was perfused with Na and Cl at low concentrations. No significant changes were noted when furosemide was added to the perfusion solutions. We consider it hardly likely that this small change in intracellular cytosolic free calcium concentration can be entirely responsible for full activation of renin release or full inactivation of the TGF control mechanism. It would seem that the signal transmission from the macula densa cells could occur by other routes than through activation of intracellular cytosolic free calcium concentration. 相似文献
90.
Terry?O?Herndon Salvador?Gonzalez TR?Gowrishankar R?Rox?Anderson James?C?WeaverEmail author 《BMC medicine》2004,2(1):12